First, the good news: the number of cases of prostate cancer overall does not appear to be increasing. However, new research from Northwestern University indicates that new cases of metastatic prostate cancer (the type that has spread beyond the prostate) has risen 72 percent between 2004 and 2013. Men between the ages of 55 and 69 showed the largest rise, at 92 percent. This finding is especially disturbing because men in this age range are generally believed to be the ones most likely to benefit from prostate cancer screening and early treatment.
What does the metastatic prostate cancer study say?
According to the study, which appears in Prostate Cancer and Prostatic Diseases, the researchers evaluated data from 767,550 men from 1,089 facilities. They noted that beginning in 2007, the incidence of metastatic prostate cancer increased, especially in the age group mentioned. In addition, the average prostate-specific antigen (PSA) values of men diagnosed with metastatic prostate cancer in 2013 was 49, which was nearly twofold higher than the average of 25 seen in men diagnosed in 2004.
The study’s senior author, Dr. Edward Schaeffer, chair of urology at Northwestern University Feinberg School of Medicine and Northwestern Medicine, noted there could be two reasons for this dramatic rise in metastatic prostate cancer cases. “One hypothesis is the disease has become more aggressive, regardless of the change in screening.” In recent years, there has been a decline in the number of men seeking prostate cancer screening because of uncertainty about the accuracy and reliability of the PSA test as well as conflicting recommendations from the American Cancer Society and the US Preventive Services Task Force. (Note that the USPSTF guidelines are currently being updated.) Concurrently, there has been a decline in the overall number of new cases of prostate cancer reported.
Schaeffer also noted that “The other idea is since screening guidelines have become more lax, when men do get diagnosed, it’s at a more advanced stage of disease. Probably both [reasons] are true.” However, he also pointed out that the number of metastatic prostate cancer cases began rising in 2008, which was before the USPSTF loosened their screening recommendations, which suggests the investigators can’t definitively link the rise in cases to reduced screening alone.
The study’s lead author, Dr. Adam Weiner, a Feinberg urology resident, said that their findings “indicate the screening guidelines and treatment need to be refined based on individual patient risk factors and genetics.” Since prostate cancer is “100 percent treatable if detected early,” explained Dr. Jonathan W. Simons, president and CEO of the Prostate Cancer Foundation, better screening techniques could help prevent the rising occurrence of this form of prostate cancer.
What are the takeaways from this study?
- Until better tests for prostate cancer are available, men should become familiar with the risks and benefits of the current PSA testing procedures and discuss this information and their personal risk factors with a qualified healthcare professional. Just because the tests are not optimal does not mean men should completely avoid them.
- Studies have shown that participation in regular exercise is associated with a reduced risk of aggressive prostate cancer. Exercise also helps men maintain a healthy weight, which is also important since overweight and obesity are associated with an increased risk of prostate cancer.
- Men should have their vitamin D levels checked, given that low levels of this nutrients are associated with more aggressive prostate cancer. Your doctor may recommend a vitamin D supplement and/or more exposure to sunlight.
- Enjoy a totally or mostly plant-based diet. Consuming lots of meat, dairy, and other animal foods has been associated with prostate cancer.
- Get an abundance of omega-3 fatty acids, which fight inflammation and can reduce the risk of developing prostate cancer. Foods rich in omega-3 include salmon, sardines, and tuna.
- Avoid exposure to toxins as much as possible. Carcinogenic ingredients can be found in pesticides (on food and in your home and garden products), personal health products, dry cleaning, building supplies, plastics, and other common items. Read labels, ask questions, and use all-natural and/or organic products whenever possible.
- Manage stress on a daily basis. Researchers have noted that stress can trigger an immune system response that can result in uncontrollable cellular mutation, which can lead to cancer.
Hassan S et al. Behavioral stress accelerates prostate cancer development in mice. Journal of Clinical Investigation 2013 Feb; 123(2): 874-86
Weiner AB et al. Increasing incidence of metastatic prostate cancer in the United States (2004-2013). Prostate Cancer and Prostatic Disease 2016 Dec; 19(4): 395-97