The concept of “Years at risk” and why its important in your decision

An important concept regarding prostate cancer is that we think of survival rates in terms of 15 years. Other cancers, such as those that involve the breast or colon, are viewed in terms of 5-year survival rates. This difference is based on prostate cancer being, as a rule, a slow-growing cancer. I said “as a rule” because not all forms of prostate cancer are slow growing, which is why the specifics of the biopsy are important. The general perception that prostate cancer is slow-growing is sometimes used as an argument by patients who do not want to pursue a biopsy in the first place. The irony of this belief is that you have to have a biopsy to make the diagnosis of prostate cancer, and you need the results of the path report to know whether you have an aggressive (i.e. high Gleason’s score) prostate cancer instead of the more common, slow-growing type.  This mistaken belief, as well as the “I have no symptoms” argument, is often responsible for the delay in the diagnosis.

The effect of the 15-year survival concept of prostate cancer on your decision depends on your age and years at risk for recurrence of the disease. Using the years at risk concept in helping you make your decision usually results in the younger patient going for a more aggressive treatment and the older patient being less aggressive. Consider two patients with favorable biopsy results, one 75 years old and in marginal health, and the other 60 years old and in excellent health. If the biopsy indicates for both an 85% survival rate after 15 years, the older patient will likely either do nothing (surveillance) or choose the least invasive, least risky treatment option. In contrast, the 60-year-old patient will most likely be alive at 75. His years at risk are greater and risk of surgical complications is lower, thus he would be inclined toward more aggressive treatments. If cancer reoccurs after radiation, it usually does so within 5-8 years. Knowing this, a 75-year-old patient, if he elects to be treated at all, would pursue radiation under the assumption that if the cancer did return, he’d be well into his eighties and at risk for many other age-related medical problems. This is why patients will often offer up the commonly referenced half-truth, “Don’t patients die with prostate cancer instead of dying of it?” In this case, the saying is correct for the 75-year-old, but it would not apply to a patient with more years at risk and/or more unfavorable parameters in his biopsy.

Physicians often evaluate the “physiologic” age rather than the chronological age of the patient. A 75-year-old man in good health, with no other medical problems and a family history of longevity, may have the physiologic age of a 65-year-old man. This age is also a factor that should be considered by the patient and doctor in making the decision.