Superiority of surgery is seen at 10 years.
Prostatectomy offers the best chance of long-term prostate cancer-specific survival for men with localized prostate cancer, according to researchers.
In an observational study, Christine Bouchardy, MD, MPH, of Geneva University in Switzerland, and her colleagues compared the effects of prostatectomy, radiation therapy, watchful waiting, and hormone therapy on short- and long-term mortality. The patients had a mean age of 71 years (range, 44-97 years) and a mean follow-up of 6.7 years.
Ten-year prostate cancer-specific survival was 83%, 75%, and 72% for men treated with surgery, radiotherapy, and watchful waiting, respectively, the researchers reported in Archives of Internal Medicine (2007;167:1944-1950). At 10 years, patients treated with radiation or watchful waiting had a significant twofold higher risk of death from prostate cancer compared with men who underwent surgery.
The increased mortality associated with radiotherapy and watchful waiting was observed mainly in men younger than 70 years and in patients with poorly differentiated tumors, the authors noted.
At five years, the risk of prostate cancer-related death among patients treated with radiotherapy or watchful waiting was not different from that of patients treated with prostatectomy. The risk was a significant 3.5 times higher, however, among men treated with hormone therapy.
The prostatectomy, radiotherapy, and watchful waiting groups had 158, 205, and 378 patients, respectively. Another 72 patients received hormone therapy.
Compared with surgery patients, those treated with radiotherapy and watchful waiting were older and had slightly higher PSA values at diagnosis.
With respect to study limitations, the investigators noted that, as with observational studies in general, treatments were not randomly allocated. In addition, the researchers lacked information on comorbidities.
“Until clinical trials provide conclusive evidence, physicians and patients should be informed of these results and their limitations,” the authors concluded.
To their knowledge, their study is the first to compare the effect of all treatment methods for prostate cancer on prostate cancer-specific mortality after adjusting for potential confounders, they noted.