What Factors Lead to a Prostate Cancer Recurrence? A HealthCentral Explainer
It’s estimated that 90 percent of prostate cancer cases remain dormant and do not require clinical attention. However, when the cancer does show signs of growth, prostate cancer treatment generally is very effective. Nearly 100 percent of men survive the cancer five years after diagnosis, after 10 years the survival rate is 98 percent and after 15 years the survival rate is 91 percent.
The survival rates by stage of the cancer tells a different story. With stage I, II, III and some stage IV cancers (before the cancer has reached the lymph nodes, but has spread outside the prostate gland), the survival rate is nearly 100 percent. But stage IV cancer that has spread to the lymph nodes, bones and other organs has only a 29 percent survival rate. So early diagnosis is key to maximizing survival rate.
Despite the high survival rates after diagnosis, according to the Prostate Cancer Foundation, it is estimated that between 20 and 30 percent of men will have a relapse five years after their initial treatment. In many cases, the disease shows signs of recurrence and could be growing again. This can be tracked via PSA levels in the blood, which may lead to additional testing. After initial treatment, the PSA levels should return to normal levels, but a rise in PSA could indicate a recurrence.
What factors can lead to a recurrence of prostate cancer? How can a recurrence be prevented?
It is clear that, according to the aforementioned survival rates, early detection of the initial prostate cancer is the key to effective treatment. Similarly, catching a recurrence before it can spread to other parts of the body increases the chances of eliminating the cancer again. New testing, including urinary PSA tests, could contribute to the early detection of recurrences.
In addition to obesity increasing the risk of developing prostate cancer, excess body weight is also linked to recurrence. The results of a recent study conducted at the School of Public Health at the University of Illinois indicate that patients with the "upper quartile for BMI" were eight times more likely to have prostate cancers prone to recurrence. Those with "upper-middle" BMI had a recurrence risk of 6.5 times more likely than moderate BMI patients.
Recent research at Duke University studied 1,262 men who had undergone a radical prostatectomy for the treatment of prostate cancer. In general, the study found that diabetics were at a higher risk of recurrence. This may be tied to obesity, which can increase the possibility of recurrence.
[QUIZ: Which Foods Fight Prostate Cancer?** _]SA Level After Treatment**
According to HealthCentral's Prostate Expert Dr. Jay Motola, "rising PSA becomes the means of determining if there is any evidence of recurrence." Though there is much debate about the usefulness of routine PSA exams, rising PSA levels can indicate a recurrence of prostate cancer.
New studies performed at the Princess Margaret Hospital Cancer Program, University Health Network, indicates that low oxygen levels in a prostate cancer tumor can be used to predict whether or not a recurrence is likely. This test can be performed even before the initial treatment, as the low oxygen levels may indicate the presence of genetic factors which contribute to recurrence.
Androgen suppression is a common treatment for prostate cancer. Drugs are used to essentially "starve" the cancer of the proteins used to create testosterone, which is the fuel by which the cancer grows. This therapy, according to research published in the Journal of American Medical Society, may reduce the risk of recurrence. The study observed men who underwent radiation therapy and men who underwent radiation therapy with androgen suppression therapy. Of the 1,500 total men studied, those who took androgen suppressors were less likely to experience a recurrence.
A recent study indicates that men who have prostate cancer and smoke are more likely to have a recurrence. The study also linked smoking at the time of the cancer with aggressive prostate cancer, heart disease and overall mortality. Men who smoked had a 61 percent higher rate of recurrence than men who did not smoke.
Does prostate cancer recurrence increase mortality rates?
With low mortality rates among men who have prostate cancer, one must ask whether or not a recurrence increases the likelihood of death from prostate cancer. New studies indicate that nearly half of survivors from prostate cancer die from another condition unrelated to cancer. Patients died from many other causes, especially heart disease, at a rate similar to the population never diagnosed with cancer. Unfortunately, as stated by lead researcher Dr. Yi Ning, "After the detection of cancer, clinicians and cancer survivors pay less attention to the prevention and treatment of other disease and complications."
American Association for Cancer Research. (5 April 2012). Mortality In Nearly Half Of Cancer Survivors Due To Conditions Other Than Cancer. Medical News Today. Retrieved from http://www.medicalnewstoday.com/releases/243738.php.
American Cancer Society. (27 February 2012). Survival Rates for Prostate Cancer. Learn About Cancer. Retrieved from http://www.cancer.org/Cancer/ProstateCancer/DetailedGuide/prostate-cancer-survival-rates.
American Association for Cancer Research. (5 April 2012). Risk For Prostate Cancer Recurrence Increased By Excess Body Weight. Medical News Today. Retrieved from http://www.medicalnewstoday.com/releases/243739.php.
DeWeese, Theodore L. (18 August 2004). Radiation Therapy and Androgen Suppression as Treatment for Clinically Localized Prostate Cancer. Journal of American Medical Association, 292 (7), 864-866. doi: 10.1001/jama.292.7.864.
Dwyer, Marge. (21 June 2011). Smoking May Increase Risk of Prostate Cancer Recurrence, Death. Harvard School of Public Health. Retrieved from http://www.hsph.harvard.edu/news/press-releases/2011-releases/smoking-prostate-cancer-kenfield.html.
Prostate Cancer Introduction. (n.d.). A.D.A.M. Medical Encyclopedia. HealthCentral.com. Retrieved from http://www.healthcentral.com/prostate/prostate-cancer-introduction-000033_1-145.html.
University Health Network. (3 April 2012). Prostate Cancer Recurrence Predicted By Oxygen In Tumors. Medical News Today. Retrieved from http://www.medicalnewstoday.com/releases/243631.php.