Active surveillance—sometimes referred to as “watchful waiting”—may be acceptable treatment for low-risk prostate cancer, according to the results of a study published early online in the Journal of the National Cancer Institute.[1] 

Men with early-stage prostate cancer have the option of being treated with radiation therapy, surgery, or no therapy until symptoms appear (watchful waiting). The choice of treatment is difficult, as there is no clear proof that early treatment prolongs survival compared with treatment that is deferred until there is evidence of disease progression. In part, this is because prostate cancer often occurs in older individuals who die of other causes before they die of prostate cancer. Watchful waiting may help some men avoid unnecessary treatment and potentially long-lasting side effects.

An observational study in Sweden included 6,849 patients, age 70 or younger with localized prostate cancer; 2,686 of these patients were considered low-risk (stage T1, Gleason score 2-6 and PSA <10 ng/mL). Among this cohort, 2,021 patients received active surveillance (or watchful waiting), 3,399 underwent radical prostatectomy, and 1,429 received radiation therapy.

After a median follow-up of 8.2 years, there were 413 deaths in the surveillance group (20.4%), 286 deaths in the prostatectomy group (8.4%), and 196 deaths in the radiation group (13.7%). There was a much higher rate of death from competing causes (i.e., causes other than prostate cancer) in the surveillance group (19.2%) compared with the prostatectomy group (6.8%) and radiation group (10.9%). This suggests that perhaps patients with an already shorter life expectancy were more often treated with surveillance rather than surgery or radiation.

When analyzing the data for the entire cohort (both low and intermediate-risk), the cumulative 10-year prostate cancer-specific mortality rate was 3.6% in the surveillance group compared with 2.7% in the surgery/radiation group. Among the low-risk group, the 10-year prostate cancer-specific mortality was 2.4% in the surveillance group and 0.7% in the surgery/radiation group. Based on these data, the researchers concluded that surveillance may be a suitable treatment option for men with low-risk prostate cancer.

Reference:

[1] Stattin P, Holmberg E, Johansson JE, et al. Outcomes in localized prostate cancer: National Prostate Cancer Register of Sweden follow-up study. Journal of the National Cancer Institute [early online publication]. June 18, 2010.