We often focus on cancers that are lethal, and especially those that can’t be treated, and for obvious reasons. This week, the National Institutes of Health addressed a different concern- that sometimes a cancer that isn’t life threatening is best left alone. In this case, it is prostate cancer, which affects about 30 to 40 percent of men over 50. About 240,000 men are diagnosed with prostate cancer a year, and over 30,000 die of the disease – so it is far from being rare or harmless for many. However, over half of prostate cancers are localized and many will never be life-threatening. In fact, three out of four men over 80 have prostate cancer, but often have no symptoms.

In the case of these relatively benign cancers, the treatment can be worse than the disease: surgery or radiation therapy can lead to loss of urinary control or diminished sexual function. The question is what to do? The answer, it seems, is to watch and wait. Luckily, there is a way to predict the outcome of prostate cancer. By monitoring the level of prostate-specific antigen and by examining tumor cells with a microscope, low-risk cancers can be identified.
Once identified, patients with these cancers can be monitored to ensure the cancer doesn’t progress, avoiding or delaying the possible side effects of treatment. This may let up to 100,000 men a year that have treatment for prostate cancer rest more easily, by opting for surveillance rather than treatment. The details of how best to monitor the patients still need to be figured out, but many will never need treatment. In fact, these types of cancer are so unlikely to be threatening that the NIH panel suggested not calling them cancer at all, if only to avoid anxiety on the part of patients.

This isn’t the only case when relatively harmless growths found during screening are treated aggressively when it may not be necessary. It is more complicated and scientists don’t always agree, but this may also be true for some breast cancers and certain forms of thyroid cancer. So, although being diagnosed with cancer is certainly a shock, it is important to discuss the costs and benefits of different approaches with your doctor to come up with the best plan.