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Running For More…

The personal blog and website of Kristen Cincotta

Posts Tagged ‘NCI’

#NHBPM Post 3: Stomach Cancer Awareness Month!

Wednesday, November 7th, 2012

Note: This post is a part of WeGo Health‘s National Health Blog Post Month: 30 posts in 30 days challenge. The prompt for Day 3 that I’m responding to is “I don’t know about this, but I’d like to…”. To see the rest of my #NHBPM posts, please click on the image at the bottom of this post.

So, as noted in my #NHBPM header introduction, the prompt for “Day 3” was “I don’t know about this, but I’d like too… ” which seems like the perfect time to write another post in my Cancer Awareness Months series. As I’ve written before, while I choose to focus my efforts primarily on breast cancer awareness and advocacy, I feel that it is important for all cancer advocates to have some familiarity with each of the major cancer subtypes. So using the “Awareness Months” as my guide, I’ve been researching and writing brief synopses on different subtypes of cancer, which can all be found filed under the blog category “Cancer Awareness Months”. The month of November serves triple duty as Lung Cancer Awareness Month, Pancreatic Cancer Awareness Month, and Stomach Cancer Awareness Month, which is what I’m going to be writing about today.

Stomach Cancer Awareness Month was started in 2010 by the group No Stomach for Cancer. They chose November because it is “a month known for the pleasure of eating”. With so many of us thinking about our bellies this month, this is the perfect month to shine a spotlight on this widely overlooked type of cancer. In fact, while mortality has been declining over recent decades (especially here in the United States), stomach cancer is still the second leading cause of cancer death word wide.

About Stomach Cancer

Stomach cancer, which is also commonly referred to as gastric cancer, is any cancer that forms in the tissues lining the stomach. The stomach itself is actually made up of five distinct tissue layers:

  1. Inner layer/lining (or mucosa): the site of digestive enzyme production and the most common origination site for stomach cancers.
  2. Submucosa: the supportive tissue layer for the inner layer of the stomach.
  3. Muscle layer: the location of the muscles responsible for digestive contractions that keep food moving through the GI tract.
  4. Subserosa: the supportive tissue layer for the outer layer of the stomach.
  5. Outer layer (or serosa): the tissue that covers the exterior of the stomach and holds it in place within the abdomen.
Per the NCI page on stomach cancer, this type of cancer usually begins in the cells of the inner layer of the stomach and can, over time, grow and invade the deeper tissues of the stomach wall. This type of stomach cancer is called adenocarcinoma and accounts for 90-95% of all malignant stomach tumors. The other three less common types of cancer found in the stomach are:
  1. Lymphoma, which is a cancer of the immune system that is sometimes found in the wall of the stomach. Lymphomas (which I wrote about in more detail here) account for ~4% of all stomach cancers.
  2. Carcinoid tumors, which start in the hormone -making cells of the stomach. These tumors account for ~3% of all stomach cancers.
  3. GI stromal tumors (or GIST), which originate in a specific type of cell in the stomach wall known as the interstitial cells of Cajal. These types of tumors can be found anywhere along the GI tract, although they are most commonly found in the stomach. Even so, GI stromal tumors are very rare among stomach cancers.
Risk Factors for Stomach Cancer
While we don’t know the direct cause (or more likely, causes) of stomach cancer, a number of risk factors have been identified, the management of which has led to the aforementioned decline in stomach cancer mortality here in the United States. I’m going to go through a number of these risk factors in more depth, but in general, factors that contribute to gastric inflammation and poor nutrition (which itself contributes to gastric inflammation) can have a large impact on a person’s risk for developing stomach cancer. As a result, stomach cancer is much more prominent in less developed countries (and in the less well off segments of developed countries as well) where healthy food, clean water, and proper refrigeration are not widely available.
Some of the recognized risk factors for stomach cancer include:
  • Infection with Helicobacter pylori bacteria. H pylori is a very common infection of the inner lining of the stomach. It is estimated that up to two-thirds of the world’s population is harboring H pylori at any given time, the majority of whom will suffer no ill consequences of this infection. In order to survive within the acidic environment of the stomach, these bacteria actively convert nitrites/nitrates from our food into ammonia, which can irritate the stomach lining resulting in peptic ulcers, among other complications. When left untreated over the long term, this irritation to the stomach walls can leave those tissues at a greater risk for developing cancer. H pylori is spread from person to person via contaminated food and water or through mouth to mouth contact. While H pylori is still very common around the world, the increasingly widespread use of antibiotics to treat other infections in developed countries has had the incidental effect of reducing H pylori infection rates in those countries. You can read more about the connections between H pylori and cancer here.
  • Eating a poor diet consisting of high amounts of smoked/pickled/salted foods and low amounts of fresh fruit and vegetables. This type of diet is thought to increase risk for stomach cancer due to the high amounts of nitrites/nitrates in foods that have been preserved using these methods, which again can contribute to lower stomach acidity and long term inflammation of the stomach tissues. Fruits and vegetables, with their plethora of good for you vitamins and minerals are thought to counteract some of these ill effects and are generally easier on the stomach. The advent of refrigeration has led to a significant decrease in preservation via smoking/pickling/salting and, when coupled with the increased ability to keep fresh fruits and vegetables on hand year round, has led to a significant reduction in stomach cancer around the world, and especially here in the United States and in Europe.
  • Pernicious anemia. Pernicious anemia is a form of anemia that is caused by a deficiency in vitamin B12.
  • Previous stomach surgeries or illnesses. Because these operations or conditions can alter the enzymatic balance within the stomach and leave the tissues irritated, having a history of GI surgeries or distress is associated with a higher risk for developing stomach cancer. This includes having a personal history of other forms of stomach cancer, including lymphoma and GIST.
  • Smoking. Smokers have twice the risk of developing stomach cancer as non-smokers, likely to due increased irritation of the stomach tissues.
  • The usual suspects. As with most other forms of cancer, age, obesity, lack of physical activity, and a family history of stomach cancer are also considered risk factors for stomach cancer.

To learn more about the risk factors associated with stomach cancer, I highly recommend the American Cancer Society’s webpage on the topic, here.

The Statistics

It is estimated that 21,320 people will be diagnosed with stomach cancer in 2012, with the majority of those diagnoses (13,020) occurring in men. 10,540 people will die of stomach cancer in that same time period. 26.9% of all people diagnosed with stomach cancer live at least five years following initial diagnosis. One in 116 people will be diagnosed with stomach cancer at some point in their lifetimes, with diagnoses in men being more common. Thankfully, for reasons discussed in the previous section, the incidence rate has been steadily dropping since the 1930s when stomach cancer was the leading cause of cancer death here in the United States. However, due to lack of refrigeration, unhealthy diets, and contaminated water, stomach cancer is still very common in other parts of the world where it remains the second leading cause of cancer death. It is estimated that the United States spends ~ $1.6 billion annually on treating stomach cancer.

The NCI allocated $14.5 million (or 0.29%) of their budget for stomach cancer research in 2010, the most recent year for which those statistics were available.

Recommended Resources

If you would like to learn more about stomach cancer, I highly recommend reading through the NCI’s web pages dedicated to stomach cancer, which can be found here. Their “What You Need To Know” section is particularly informative, as is the “snapshot” report on stomach cancer, especially the section discussing recent research investments and findings. I also found the American Cancer Society’s Learn About Cancer: Stomach Cancer section to be very useful. All of the statistics cited in the post were from the Surveillance Epidemiology and End Results (SEER) fact sheet on thyroid cancer, which can be found here. These webpages were my primary sources of information for this blog post.

The American Association for Cancer Research does not have any specific recommendations for organizations dedicated to stomach cancer research, stomach cancer advocacy, or patient support for those diagnosed with stomach cancer. However, the following organizations are (to the best of my knowledge) considered to be leaders in the field and may be worth consulting:

No Stomach for Cancer, the founders of Stomach Cancer Awareness Month

Can’t Stomach Cancer

The Gastric Cancer Foundation

The Life Raft Group, an organization that focuses on GI stromal tumors.

As with all of these cancer awareness posts, I hope that everyone reading this found it helpful and informative. I know I learned a lot researching it and will be a more effective cancer advocate for it!

Note: While I am a biomedical scientist, I am not considered an expert (medical or otherwise) on stomach cancer. This post, as with all of my “awareness month” posts, is not meant to be an in depth review of stomach cancer. Rather, I only wanted to provide a brief overview of stomach cancer in order to help further the larger cancer community’s awareness of this common cancer. Moreover, while I provided links to a number of stomach cancer organizations at the end of this post, I have not researched these organizations to the extent that I do for my “Spotlight On” series of posts. Until I can research them further, I am not explicitly advocating financial donations to these organizations (although I certainly won’t advise you against it either should you find them worthy!). Instead, I am recommending them here because each organization is a well respected leader in these specific areas and is considered a reputable source for further information on stomach cancer.

 

Thyroid Cancer Awareness Month!

Thursday, September 27th, 2012

September was a busy month full of cancer awareness observances and I’m not quite done yet!

As I’ve mentioned in the introductions to the other “cancer awareness month” posts that I’ve written, I believe very strongly that even though I identify myself as primarily a breast cancer advocate, it is important for me to have some level of understanding of the other major cancer types. To help broaden my knowledge, I’ve been using the various cancer awareness observances as my guide for which cancers to research and write about. And as it turns out, there are A LOT of them in September. Over the course of the last few weeks, I’ve written posts touching on Childhood Cancer Awareness Month, Blood Cancers Awareness Month, Ovarian and Gynecological Cancers Awareness Month, and Prostate Cancer Awareness Month. Today, to wrap things up, I’m going to write a little bit about thyroid cancer in honor of Thyroid Cancer Awareness Month.

Thyroid Cancer Awareness Month was first initiated by ThyCa: Thyroid Cancer Survivors Association back in 2000. When it was originally founded, it was only a week long observance that was extended for the full month of September in 2003. As ThyCa puts it on their website:

Thyroid Cancer Awareness Month promotes thyroid cancer awareness for early detection, as well as care based on expert standards and increased research to achieve cures for all thyroid cancer.

In my reading, I came across some assertions that due its relatively low mortality rates, thyroid cancer was the “good” cancer to get. Well, that’s just ridiculous. All cancer sucks because all cancer can and does kill people. There is no such thing as a “good” cancer to get. And with the fastest increasing incidence rate of all cancers in both men and women, it’s time to pay more attention to thyroid cancer!

About Thyroid Cancer

Thyroid cancer, following the traditional naming conventions in oncology, is any cancer that forms in the thyroid gland. That part should be pretty straightforward by now. But what exactly is the thyroid gland? Well, the thyroid gland is a small organ at the base of the throat, just below the larynx (voice box) that makes hormones to regulate the rate of metabolism. The thyroid is shaped sort of like a butterfly, with two larger lobes connected by a small piece of tissue called the isthmus. In healthy individuals, the thyroid is a little larger than a quarter and can’t be felt manually through the skin. The thyroid is composed of two primary hormone producing cells:

  1. Follicular cells, which use iodine from the blood to make the not so creatively named thyroid hormone (TH). TH is produced in response to increasing levels of the also not so creatively named thyroid stimulating hormone (TSH), which is generated and released from the pituitary gland. Because TH is required for metabolism, improper levels of TH can have a whole host of side effects. Someone who has too much TH (called hyperthyroidism), for example, often experiences irregular heartbeat, trouble sleeping, nervousness, hunger, weight loss, and feeling to warm. Having too little TH (which is called hypothyroidism), on the other hand, can cause a person to feel slow and fatigued and to gain weight.
  2. C cells, or parafollicular cells as their also called, which are responsible for producing calcitonin, a hormone that helps regulate how the thyroid uses calcium.

Thyroid cancer can develop in either thyroid cell type, giving rise to four major subtypes of thyroid cancers: papillary carcinoma, follicular carcinoma, medullary thyroid cancer, and anaplastic thyroid cancer. Let’s go through each one, one at a time.

The most common subtype of thyroid cancer is papillary carcinoma, which develops from the follicular cells. Because these are glandular cells, this type of thyroid cancer is also sometimes referred to as papillary adenocarcinoma. Papillary carcinomas, which account for 86% of all thyroid cancers, are generally slow growing, although they are prone to spreading into the lymph nodes of the neck. These cancers are usually isolated to only one lobe of the thyroid, although not always. Papillary carcinomas can usually be treated and are rarely fatal.

The second most common subtype of thyroid cancer is follicular carcinoma, which accounts for 9% of all thyroid cancer diagnoses. Follicular thyroid cancer is very similar to papillary thyroid cancer in that both types of cancer originate in the follicular cells and are relatively slow growing. However, unlike papillary thyroid cancer, follicular thyroid cancer generally doesn’t spread to the lymph nodes. Follicular thyroid cancer is most common in countries lacking dietary iodine. The prognosis for individuals diagnosed with follicular thyroid cancer is generally good, although not quite as strong as for those with papillary carcinoma. This is at least in part due to the relatively poor prognosis for the Hürthle cell carcinoma subtype of follicular cancer. Because Hürthle cell follicular carcinomas do not readily absorb radioactive iodine, they are often diagnosed at later stages and are much more difficult treat.

The third major subtype of thyroid cancer is medullary thyroid cancer, or MTC. Unlike the previous two subtypes, MTC develops from the c-cells of the thyroid. MTC, which accounts for 2% of all thyroid cancers, often results in abnormally high levels of calcitonin. MTC is usually slow growing and is treatable if caught before the cancer spreads to other parts of the body. MTCs can be linked to inherited mutations in the RET. This form of MTC, which I’m going to talk about more later in this post, is known as familial medullary thyroid cancer and accounts for 25% of all MTCs.

The most rare form of thyroid cancer is anaplastic thyroid cancer, which accounts for approximately 1% of all thyroid cancers. Anaplastic thyroid cancer also develops in the follicular cells, and is thought to sometimes develop from an existing papillary or follicular cancer. Because anaplastic cancer cells are highly dysmorphic and do not resemble healthy thyroid cells when examined under a microscope, anaplastic thyroid cancer is sometimes described as “undifferentiated” thyroid cancer. Anaplastic thyroid cancer is the most aggressive form of thyroid cancer, rapidly invaded the neck and then spreading to other parts of the body. Because of this, anaplastic thyroid cancer is relatively hard to treat.

Finally, while it is not technically a form of thyroid cancer, I wanted to just briefly write about parathyroid cancer, which is any cancer that develops from the four tiny parathyroid glands located at the back of the thyroid. Parathyroid cancer is very rare (with less than 100 cases occurring in the US each year) and generally results in elevated levels of calcium in the blood due to calcium dysregulation. Parathyroid cancer is much more difficult to cure than thyroid cancer.

While the cause of every form of thyroid cancer remains unknown, there have been a handful of risk factors that have been identified. For as yet unknown reasons, thyroid cancer is three times more common in women than in men. Moreover, women tend to be diagnosed with thyroid cancer at a younger age, with the peak rate of diagnosis for women occurring in their 40s and 50s while the peak rate of diagnosis occurring in their 60s and 70s. Eating a diet that is low in iodine has also been shown to increase the risk of developing thyroid cancer, although due to dietary supplements like iodized table salt, this isn’t generally a concern here in the US. While exposure to radiation can increase your risk of developing cancer in general, radiation exposure seems to be particularly strongly linked to an increased risk for thyroid cancer. This includes both exposure to medical radiation as a child and nuclear fall out from living near atomic bomb testing sites and disasters such as the meltdown of the Chernobyl nuclear power station. Finally, there have been a number of genetic mutations linked to the various subtypes of thyroid cancer, which I’m going to talk about in the next section.

The Genetics of Thyroid Cancer

There are two primary types of genes that, when mutated, can result in cancer:

  1. Oncogenes: These are genes that promote growth and cell division. These types of genes are usually turned “off” and are only switched on under highly regulated circumstances. When an oncogene becomes mutated, it becomes permanently turned on (and in some cases turned way up!), resulting in uncontrolled cell growth and division.
  2. Tumor suppressor genes: These are genes that are normally responsible for turning off the oncogenes and stopping cell growth and division before it gets out of control. When tumor suppressor genes become mutated, the off switch essentially is broken, allowing cells to continue growing and multiplying. The rate of cell growth and division isn’t higher, it’s just that the stop light is busted. As a result, mutations in tumor suppressor genes generally result in less aggressive forms of cancer.

Different cell types in the body seem to have certain genes that are more vulnerable to cancer-causing mutations than others. These mutations can be either inherited (meaning you were born with a bum form of the gene) or acquired (meaning you picked up that damage at some point during your life). Cancer due to inherited mutations is known as familial cancer and cancer that is due to acquired mutations is known as sporadic cancer. One of the great challenges in cancer research, then, is to identify both the vulnerable genes associated with each cell type (and therefore associated with each cancer type) and to identify the source of the mutations in those genes. In the case of thyroid cancer, and especially MTC, we actually have uncovered the answers to a few of these genetic questions.

The primary gene that has been associated with thyroid cancer is the gene RET. The mutated form of RET is the oncogene PTC. Acquired mutations in RET have been found to play a role in some papillary thyroid cancers as well as in approximately 10% of sporadic MTCs. Inherited mutations in RET, though, underly almost all cases of familial MTC. Nearly everyone who inherits a mutated form of RET ultimately develops MTC. As a result, if someone has a strong family history of MTC, many doctors will recommend genetic testing and potentially prophylactic removal of the thyroid as a means of preventing thyroid cancer.

Other oncogenes that have been associated with thyroid cancers include:

  • BRAF (oncogene) – mutations in BRAF have been associated with 30-70% of papillary thyroid cancers
  • NTRK1MET (oncogenes) – less common than BRAF mutations, mutations in these two genes have also been linked to papillary thyroid cancer
  • RAS (oncogene) – mutations in RAS have been linked to follicular thyroid cancer
  • p53 (tumor suppressor gene), CTNNB1 – mutations in these two genes have been linked to anaplastic thyroid cancer.

Hands down, the most important breakthrough in cancer research has been the recognition that cancer is ultimately a disease caused by genetic mutations. While we still have a lot of questions still to answer when it comes to the genetics of cancer, seeing how far we’ve come in understanding the genetic basis of thyroid cancer gives me hope that those elusive answers for all cancers are closer to being discovered than ever before.

The Statistics

It is estimated that 56,460 people will be diagnosed with prostate cancer in 2012, with 43,210 of those diagnoses occurring in women. 1780 people will die of thyroid cancer in that same time period. 97.5% of all people diagnosed with thyroid cancer live at least five years following initial diagnosis. One in 97 people will be diagnosed with thyroid cancer at some point in their lifetimes. The NCI allocated $16.2 million (or 0.32%) of their budget for thyroid cancer research in 2011, the most recent year for which those statistics were available.

Recommended Resources

If you would like to learn more about thyroid cancer, I highly recommend reading through the NCI’s web pages dedicated to thyroid cancers, which can be found here. Their “snapshot” report on thyroid cancer is particularly informative, especially the section discussing recent research investments and findings. I also found the American Cancer Society’s Learn About Cancer: Thyroid Cancer section to be very useful. All of the statistics cited in the post were from the Surveillance Epidemiology and End Results (SEER) fact sheet on thyroid cancer, which can be found here. These webpages were my primary sources of information for this blog post.

The American Association for Cancer Research recommends ThyCa: Thyroid Cancer Survivors’ Association for additional thyroid cancer advocacy and patient support information. I also recommend the Light of Life Foundation for more information about thyroid cancer in general and to learn how you can get more involved in advocating for thyroid cancer research.

As with all of these cancer awareness posts, I hope that everyone reading this found it helpful and informative. I know I learned a lot researching it and will be a more effective cancer advocate for it!

Note: While I am a biomedical scientist, I am not considered an expert (medical or otherwise) on thyroid cancer. This post, as with all of my “awareness month” posts, is not meant to be an in depth review of thyroid cancer. Rather, I only wanted to provide a brief overview of thyroid cancer in order to help further the larger cancer community’s awareness of this common cancer. Moreover, while I provided links to a number of thyroid cancer organizations at the end of this post, I have not researched these organizations to the extent that I do for my “Spotlight On” series of posts. Until I can research them further, I am not explicitly advocating financial donations to these organizations (although I certainly won’t advise you against it either should you find them worthy!). Instead, I am recommending them here because each organization is a well respected leader in these specific areas and is considered a reputable source for further information on thyroid cancer.

Prostate Cancer Awareness Month!

Tuesday, September 25th, 2012

Pushing on with my series of cancer awareness months, today I’m going to be writing about prostate cancer in observance of Prostate Cancer Awareness Month. After writing long posts for Childhood Cancer Awareness Month, Blood Cancer Awareness Month, and Ovarian/Gynecological Cancer Awareness Month, this post is hopefully going to be a bit more concise. However, that doesn’t mean prostate cancer isn’t as important as these other cancers. In fact, prostate cancer is the most common cancer in men outside of non-melanoma skin cancer and is the second leading cause of cancer death in men. So as a cancer advocate, I think it’s important to learn a bit more about this very common form of cancer!

About Prostate Cancer

The prostate is a gland within the male reproductive system that is located in front of the rectum and just below the bladder, where it surrounds the urethra. The prostate is responsible for producing the liquid component of the seminal fluid that helps to carry the sperm out of the body as part of the semen. The prostate grows rapidly during puberty in response to a testosterone derivative called dihydrotestosterone (or DHT). The healthy adult prostate is generally the size of a walnut and does not continue to grow larger with age, although a variety of conditions can result in an enlarged prostate. The most common of these conditions is called benign prostatic hyperplasia (or BHP), which generally only results in serious medical complications when the enlarged prostate begins to squeeze and constrict the urethra.

Prostate cancer, then, is any cancer that develops in the tissues of the prostate. Almost all prostate cancers are adenocarcinomas; that is, cancers that develop from the glandular cells of the prostate. Other (very rare) subtypes of prostate cancer include sarcomas (soft tissue cancers), small cell carcinomas, and transitional cell carcinomas. It is important to note that BHP is NOT a form of prostate cancer. While some prostate cancers can grow and spread very rapidly, the majority of prostate cancer grow incredibly slowly. These slow progressing cancers are often present within the prostate for years to decades before they begin to have any kind of symptomatic effects on the individual harboring the cancer.

While prostate cancer is not known to be caused by HPV infection, the slow growth of prostate tumors results in a long precancerous stage that is similar to that seen in cervical, vaginal, and vulvar cancers. These precancerous changes are known as prostatic intraepithelial neoplasia (or PIN) and can be classified as either high- or low-grade PIN. It is estimated that nearly half of all men will develop some degree of PIN by age 50. Men with high-grade PIN have a 20-30% chance of harboring prostate cancer at another site within the gland. The relationship between low-grade PIN is much less clear and may not be related to prostate cancer at all.

The primary risk factor for prostate cancer is age, with two-thirds of all prostate cancers being diagnosed in men over the age of 65. Prostate cancer is very rare in men under the age of 40. Certain races also appear to have a higher risk of prostate cancer. For example, prostate cancer is more common in African American men, who are also twice as likely to die from the disease. The reason for this increased risk is unknown at this time. A family history of prostate cancer is also linked to a higher risk of developing prostate cancer, with 5-10% of prostate cancers having a known genetic basis. Interestingly, while mutations in the BRCA1 and BRCA2 genes are most commonly associated with an increased risk of developing breast and ovarian cancer in women, mutations in these same genes also appear to be associated with an increased risk of prostate cancer. Finally, it appears that a diet high in red meat and dairy and low in fruits and vegetables may lead to an increased risk of prostate cancer, although the specific components of that diet that underly this increased risk are unknown.

Prostate Cancer Screening

Because there has been a lot of confusion surrounding prostate cancer screening tests, I felt like a section dedicated to the topic was warranted. There are currently two methods for screening for prostate cancer that are generally used in tandem:

  1. The prostate specific antigen (PSA) blood test, which detects elevated levels of the prostate-produced substance PSA in the bloodstream. A healthy prostate will generally (but not always) produce PSA levels between 4ng/ml of blood and 10ng/ml of blood. Men with PSA levels in this range have a 1-in-4 chance of harboring prostate cancer, while men with PSA levels above 10ng/ml have a greater than 1-in-2 chance of harboring prostate cancer. It is important to note that low PSA levels do not mean that a man is cancer-free; rather, approximately 15% of men with PSA levels below 4ng/ml are found to have prostate cancer on biopsy.
  2.  The digital rectal exam (DRE), which is a physical examination in which the doctor manually inserts his fingers (or digits) into the rectum to directly check the prostate for changes that may be related to cancer. DREs are generally used to confirm or dispute PSA test results.

These tests have unequivocally been shown to find more prostate cancers, especially in the early stages of the disease, than would otherwise be diagnosed without regular screening, resulting in a significant decline in the death rate from prostate cancer since their implementation. So why is regular screening for prostate cancer not recommended for every man over the age of 40? Well, it’s complicated. Let’s try to sort through it all.

First and foremost, while the PSA and DRE tests are good at detecting cancer, the range of biological variability inherent in the prostate (and the levels of PSA produced by it) means that they can also be inaccurate. Some men have very low PSA levels even in the presence of cancer, resulting in false negative tests. Otherwise healthy men may have elevated PSA levels due to a host of other, non-cancer, conditions, resulting in false positive tests. And the DRE suffers from anatomical limitations, again resulting in a number of inaccurate test results. So while these screening tests can be useful, they are by no means ideal.

Moreover, as noted above, prostate cancer grows VERY slowly. Many otherwise healthy men are walking around with undiagnosed prostate cancer that due to its slow rate of progression, will never cause them medical problems during their lifetimes. Regular screening, then, leads to what many in the medical community consider to be an overdiagnosis of prostate cancer. While many of these men would likely opt to treat an asymptomatic cancer should they become aware of it, the reality is that a large portion of those treatments are medically unnecessary. Ultimately, there is a growing belief that because the side effects of treating prostate cancer can have a significant impact on a man’s quality of life (much more so than the cancer ever would!), the benefits of identifying and treating these cancers in their earliest stages are not sufficient to warrant those risks for the majority of men.

In May of 2012, the United States Preventive Services Task Force (USPSTF) updated their recommendations for prostate cancer screening. The USPSTF currently does not recommend PSA screening for any men, stating that there is “moderate or high certainty that the service has no benefit or that the harms outweigh the benefits”. You can read their full report here.

The Prostate Cancer Foundation strongly disagreed with the USPSTF recommendations, and summarized both their response to the USPSTF and their position on prostate cancer screening here. They also noted, in this synopsis of the prostate cancer screening debate, that, “in contrast [to the USPSTF], physician-led groups, such as the American Society of Clinical Oncology and the American Urological Association, maintain that PSA screening should be considered in the context of a man’s life expectancy and other medical conditions.” They further note that “most experts agree that there is no role for PSA screening for men expected to live less than 10 years”.

The official position of the American Cancer Society on prostate cancer screening is in agreement with the physician-led groups cited by the Prostate Cancer Foundation. Specifically, they state that:

At this time, the American Cancer Society recommends that men thinking about prostate cancer screening should make informed decisions based on the available information, discussion with their doctor, and their own views on the benefits and side effects of screening and treatment.

The ACS specifically recommends that men of average risk for developing prostate cancer and who otherwise have every reasonable expectation of living for at least another decade should discuss screening with their doctors starting at age 50. Men of above average risk (i.e. African American men, men with one first degree relative with prostate cancer) should start having these discussions at age 45 and men of high risk (that is, men with multiple first degree relatives with prostate cancer) should start having these discussion at age 40. For men who choose to undergo regular screening, the ACS recommends that men with PSA levels below 2.5ng/ml have follow up tests every two years while men with PSA levels above 2.5ng/ml should have follow up tests annually. Men should make decisions about biopsies and additional treatments based on marked and persistent changes in these test results in consultation with their doctors.

The Statistics

It is estimated that 241,740 men will be diagnosed with prostate cancer in 2012 and that 28,170 men will die from the disease. 99.2% of all men diagnosed with prostate cancer live at least five years following initial diagnosis, primarily due to the slow rate of progression of these cancers. One in six men will be diagnosed with prostate cancer at some point in their lifetimes and one in 36 men will die from the disease, making prostate cancer the most common non-skin cancer in men and the second leading cause of cancer death. The US spends an estimated $9.9 billion on treating prostate cancer annually. For comparison, the NCI allocated $300.5 million (or 5.9%) of their budget to prostate cancer research in 201o, the most recent year for which those statistics were available.

Recommended Resources

If you would like to learn more about prostate cancer, I highly recommend reading through the NCI’s web pages dedicated to prostate cancers, which can be found here. Their “snapshot” report on prostate cancer is particularly informative, especially the section discussing recent research investments and findings. I also found the American Cancer Society’s Learn About Cancer: Prostate Cancer section to be very useful. The Prostate Cancer Foundation’s section on prostate screening recommendations, which can be found here, summarizes this complicated topic very well. All of the statistics cited in the post were from the Surveillance Epidemiology and End Results (SEER) fact sheet on prostate cancer, which can be found here. These webpages were my primary sources of information for this blog post.

If you would like to read more about the current prostate cancer screening recommendations of the USPSTF, you can find that information here.

The American Association for Cancer Research also recommends the following prostate cancer advocacy and patient support organizations:

Finally, while they weren’t listed on the AACR website, I also recommend the Prostate Cancer Foundation for more information about prostate cancer in general and to learn how you can get more involved in advocating for prostate cancer research.

I hope that every reading this found this informative. I know I learned a lot researching it and will be a more effective cancer advocate for it!

Note: While I am a biomedical scientist, I am not considered an expert (medical or otherwise) on prostate cancer. This post, as with all of my “awareness month” posts, is not meant to be an in depth review of prostate cancer. Rather, I only wanted to provide a brief overview of prostate cancer in order to help further the larger cancer community’s awareness of this very common cancer. Moreover, while I provided links to a number of prostate cancer organizations at the end of this post, I have not researched these organizations to the extent that I do for my “Spotlight On” series of posts. Until I can research them further, I am not explicitly advocating financial donations to these organizations (although I certainly won’t advise you against it either should you find them worthy!). Instead, I am recommending them here because each organization is a well respected leader in these specific areas and is considered a reputable source for further information on prostate cancer.

 

Blood Cancer Awareness Month!

Saturday, September 15th, 2012

As I mentioned in this post about Childhood Cancer Awareness Month and CURE Childhood Cancer, September is a busy month in terms of cancer awareness. While I consider myself primarily a breast cancer activist, I recognize that at the heart of every type of cancer is the same thing: formerly normal cells behaving badly, growing out control, and becoming malicious. To that end, I think that any type of cancer activist should take some time to familiarize themselves with the other major types of cancer that exist in the world and take innocent lives every day. Because today is officially World Lymphoma Awareness Day, and because the rest of the month of September is more broadly recognized as Blood Cancer Awareness Month, I thought today was a great day to write a little more about blood cancers.

Two Important Stats About Blood Cancers Worth Knowing

  1. Someone in the United States is diagnosed with a blood cancer every four minutes. (per the Lymphoma Research Foundation)
  2. Blood cancer is the third leading cause of cancer death in the US. (per the Leukemia and Lymphoma Society)

Did you know those stats? Until I started researching this post, I didn’t. I guess this is one cancer awareness month that I really need!

Blood cancer as a group is actually made up of three major types of cancer: leukemia, lymphoma, and myeloma. Each of these cancers begin as a different type of white blood cell that ultimately begins accumulating at an above normal rate, either due to increased cell production or decreased cell death. As a result of this rapid accumulation, those cells quickly become abnormal, resulting in different types of cancer, depending on the type of cell the cancer originated as. Because each of these types of cancer are such different diseases, I’m going to talk about each of the major types of blood cancer individually.

Leukemia

Leukemia is a type of cancer that starts in the bone marrow, the site of blood cell production in the body. There are three primary types of blood cells that the body produces: red blood cells (or “erythrocytes”, the cells that carry oxygen to the rest of the body), white blood cells (or “leukocytes”, which fight infection in the body), and platelets (which are responsible for clotting). In general, leukemia is the type of cancer that arises when the body accumulates cancerous leukocytes/white blood cells, or WBCs, as I’m going to abbreviate them here on out.

[Science reading comprehension tip: The prefix leuk- is derived from latin word for white, and in science/medical parlance, generally refers to white blood cells. Any term that ends in the suffix “-cyte”, is a specific type of cell. Therefore, a leukocyte is literally a white blood cell. The suffix -emia is used when referring to anything blood-related. So a blood cancer of white blood cells = leukemia.]

The body makes a huge number of different WBCs, each of which performs a different role within the circulating immune system. WBCs develop from one of two types of stem cells, depending on which type of WBC they are meant to become: myeloid stem cells (which are also the precursor cells to red blood cells and platelets) or lymphoid stem cells. Leukemias can develop from either of these stem cell types. Based on the type of stem cell that the cancer developed from and the rate at which the cancer progresses, the majority of leukemias can be classified as one of four types:

1. Chronic Lymphocytic Leukemia (CLL) – leukemia originating from lymphoid stem cells that progresses slowly. CLL affects primarily adults.

2. Chronic Myeloid Leukemia (CML) – leukemia originating from myeloid stem cells that progresses slowly. CML also affects primarily adults.

Chronic leukemia cells usually retain some degree of functionality as WBCs, at least at the beginning of the disease. Because of this, the decline in health of individuals with chronic leukemias is relatively slow. As a result, chronic leukemias can be more difficult to diagnose.

3. Acute Lymphocytic Leukemia (ALL) – leukemia originating from lymphoid stem cells that progresses rapidly. ALL is the most common leukemia in children, although it is also found in adults.

4. Acute Myelod Leukemia (AML) – leukemia originating from myeloid stem cells that progresses rapidly. AML affects both kids and adults.

Acute leukemia cells cannot function as normal WBCs, leading to a rapid decline in health for those with these types of cancer.

CLL is the most prevalent type of leukemia (accounting for approximately 15,000 new cases of leukemia per year). AML accounts for approximately 13,000 new cases of leukemia per year, while CML and ALL each account for about 5,000 new cases of leukemia per year. Other minor subtypes of leukemia also exist, and together they account for approximately 6000 new cases of cancer per year. Ultimately, it is predicted that 47,150 new cases of leukemia will be diagnosed in 2012 and 23,540 people will die from the disease. One in 74 people will be diagnosed with leukemia in their lifetimes. It is also worth noting that while leukemia affects 10x more adults than children, it is still the most common cancer diagnosed in children. In the US, we spend approximately $4.5 billion treating leukemia every year.

The National Cancer Institute (who was my source for all of this information) allocates approximately 4.7% of it’s annual budget (or $239.7 million) for leukemia research in 2010, the last year for which that information was available.

The information in this section was provided to the public courtesy of the NCI. You can find more information about leukemia in their “What You Need to Know About Leukemia” booklet, here and in their “Leukemia Snap Shot” report, here. All of the stats came from the Surveillance Epidemiology and End Results (or SEER) fact sheet on leukemia, here.

Lymphoma

Whereas leukemias originate from stem cells located in the bone marrow, lymphomas are cancers that arise from lymphoid stem cells that are found in the lymphatic system. The lymphatic system (which is part of the body’s large immune system) includes lymphocytes (a specialized subtype of WBC), the lymph vessels (found throughout the body), the lymph fluid, and the lymph nodes, which connect the various lymph vessels and act as something of a filtration system to keep the lymph fluid clear of bacteria and other infectious agents.

There are two major types of lymphomas, and further subtypes of each of those:

1. Hodgkin’s lymphoma, which is distinguished by the presence of a specific type of cancer cells called Reed-Sternberg cells. Hodgkin’s lymphoma can be further classified as either the more common classical subtype of Hodgkin’s lymphoma or the comparatively more rare nodular lymphocyte-predominant Hodgkin’s subtype.

2. Non-Hodgkin’s lymphoma, which is defined as any lymphoma that lacks Reed-Sternberg cells. There are many subtypes of Non-Hodgkins lymphoma based on the rate of progression of the disease (generally defined as either aggressive or indolent/slow), the original lymphocyte subtype that the cancer developed from, and other cellular characteristics.

Lymphomas account for 5% of all cancers in the United States, with Non-Hodgkins lymphoma being far more prevalent than Hodgkins lymphoma. It is estimated that in 2012, 70,130 will be diagnosed with Non-Hodgkins lymphoma and 9,060 will be diagnosed with Hodgkin’s lymphoma. Further, it is estimated that 18,940 people will die from Non-Hodgkins lymphoma and 1,190 people will die from Hodgkins lymphoma this year. One out of every 47 people will be diagnosed with Non-Hodgkins lymphoma and one out of every 436 people will be diagnosed with Hodgkins lymphoma in their lifetimes. In the US, we spend approximately $10.2 billion annually treating lymphoma.

NCI allocated 2.7% of its annual budget (or $137.0 million) in 2010 for lymphoma research.

The information in this section was also provided to the public courtesy of the NCI. You can find more information about lymphoma in their “What You Need to Know About Hodgkins Lymphoma” and “What You Need to Know About Non-Hodgkins Lymphoma” booklets, here and here, respectively. Additional information can also be found in their “Lymphoma Snap Shot” report, here. All of the stats came from the SEER fact sheets on Hodgkins and Non-Hodgkins leukemia, here and here, respectively.

Myeloma

Myeloma (or plasma cell myeloma as it is also known) is a type of blood cancer that originates specifically in the plasma cells. Plasma cells are a highly specialized type of white blood cell that produces antibodies. When the disease first develops, myeloma cancer cells accumulate specifically within the bone marrow, much like with leukemia. As the disease progresses, myeloma cells accumulate in multiple bones simultaneously, at which stage the disease is described as Multiple Myeloma.

Myeloma is the second most common blood cancer and accounts for 1% of all cancers in the United States. It is estimated that 21,700 people will be diagnosed with myeloma in 2012 and that 10,710 people will die from the disease in this same time frame. One in 150 people will be diagnosed with myeloma in their lifetime. NCI did not report an estimate for aggregated annual treatment costs to the country for myeloma.

NCI allocated approximately 1% of it’s annual budget (or $48.5 million) in 2010 for myeloma research.

The information in this section was also provided to the public courtesy of the NCI. You can find more information about myeloma in their “What You Need to Know About Multiple Myeloma” booklet, here. Additional information can also be found in their “Myelnoma Snap Shot” report, here. All of the stats herein came from the SEER fact sheet on myeloma, here.

Recommend Resources

If you would like to learn more about blood cancer in general, or one of these types of cancers in particular, I highly recommend reading through the NCI’s web pages dedicated to leukemia, Non-Hodgkins lymphoma, Hodgkin’s lymphoma, and Multiple Myeloma. The “snap shot” reports linked to in each subsection are particularly informative, especially the sections discussing recent research investments and findings.

 The American Cancer Society also has the following subsections of their “Learn About Cancer” webpage dedicated to blood cancers:

 The American Association for Cancer Research also recommends the following blood cancer advocacy and patient support organizations:

Finally, to learn more about the origins of World Lymphoma Awareness Day, please visit The Lymphoma Coalition.

Image source – Thanks for letting me borrow it!

 

Note: While I am a biomedical scientist, I am not considered an expert (medical or otherwise) on any of these types of cancer. This post, as with future planned “awareness month” posts, is not meant to be an in depth review of these types of cancer. Rather, I only wanted to provide a brief overview of each type of cancer in the blood cancer family in order to help further the larger cancer community’s awareness of each of these cancers. Moreover, while I provided links to a number of blood cancer organizations at the end of this post, I have not researched these organizations to the extent that I do for my “Spotlight On” series of posts. Until I can research them further, I am not explicitly advocating financial donations to these organizations (although I certainly won’t advise you against it either should you find them worthy!). Instead, I am recommending them here because each organization is a well respected leader in these specific areas and is considered a reputable source for further information on blood cancers.