My doctor advised active surveillance for my prostate cancer. What does this mean?

DEAR DOCTOR K:

After an abnormal PSA test and biopsy, I have been diagnosed with early-stage, non-aggressive prostate cancer. My doctor advised active surveillance. What does this mean?

DEAR READER:

Prostate cancer is the uncontrolled growth of abnormal cells in the prostate. This walnut-sized gland sits below the bladder, in front of the rectum, near the base of the penis. Prostate cancer is common, but it is not always dangerous.

People are often surprised to hear “cancer” and “not dangerous” in the same sentence. But these days, many prostate cancers are discovered through screening. Some of them will not grow, spread and become serious medical problems.

Of course, some of them are serious. When deciding on a course of treatment, your doctor must first determine whether your cancer is life-threatening.

Why not just treat any prostate cancer once it is diagnosed? Because treatment comes with its own risks, including erectile dysfunction and urinary incontinence. And neither you nor your doctor wants you to have a treatment if it is worse than the disease.

Indeed, some men need no treatment — for example, older men with other serious and life-threatening health issues, or men with slowly progressing early-stage cancer. Other men, say younger men with aggressive cancer, require treatment.

But today, a significant number of men fall into a gray area, where the decision of whether to treat isn’t clear-cut. Like you, these men have tumors that are so small and apparently slow-growing that they meet the criteria for active surveillance. This strategy used to be called “watchful waiting.” It involves monitoring the cancer closely and beginning treatment when and if it advances or becomes more aggressive.

At a minimum, close monitoring means digital rectal exams (DREs) and prostate-specific antigen (PSA) tests every four to 12 months. Biopsies should be done every one to three years.

Without regular monitoring, you run the risk that the cancer will grow and spread, making it much more difficult to treat. If PSA readings increase sharply, or if the doctor feels a new lump during a DRE, it may be time to start treatment. A change in urinary habits (needing to go urgently, or not being able to go, for example) can also signal that it’s time for active therapy.

Many of my patients have asked me the question you’ve asked. It’s hard to understand that not all cancers are bad for your health, and that some cancers are destined to never grow, spread and cause trouble. Or that the doctor cannot tell with perfect accuracy what the risk is that a cancer will be a “bad one” that will grow and spread, unless it is treated.

We just haven’t yet been clever enough to develop a perfect test for estimating that risk. But we have learned enough to know if a person is in the “gray area,” where active surveillance is the most sensible approach. If I were diagnosed with a prostate cancer that put me in that gray area, my choice would be active surveillance.