Wong Y-N et al. (2006) Survival associated with treatment vs observation of localized prostate cancer in elderly men. JAMA 296: 2683–2693

The proportion of men with a diagnosis of early-stage, low to intermediate grade, localized prostate cancer has increased as a result of PSA screening, although whether these patients should be managed with active treatment or watchful waiting is a subject of much debate. Wong et al. have conducted an observational cohort study in the US. Their results suggest that there is a significant survival advantage for patients >65 years of age who undergo active treatment over patients who undergo watchful waiting.

Data for 44,630 men (aged 65–80 years) with localized, well or moderately differentiated, stage T1–T2, Gleason score 2–7 prostate cancer and >1 year survival after diagnosis were obtained from Medicare records and the Surveillance, Epidemiology, and End Results (SEER) database. These patients were grouped according to whether they had received ('treatment group', n = 32,022) or had not received ('observation group', n = 12,608) active treatment (radical prostatectomy or radiation therapy) within 6 months of diagnosis.

Patients in the treatment group were 30% less likely to die during the 12-year follow-up period than those in the observation group. This association between active treatment and mortality was consistent after adjustment for a considerable number of confounding variables, such as comorbidity, sociodemographic background, ethnicity, age, and tumor variables.

The results of this observational study require validation by randomized, controlled trials; although selection bias might have influenced the outcome of the study, the survival advantage associated with treatment was consistent across the healthiest and sickest patients.