There's still some uncertainty about the management of localized prostate cancer. Clinical studies to date have mostly dealt with short-term outcomes, but there's very little on long-term results of different forms of treatment. A new study has been reported by Swiss physicians and published in the Archives of Internal Medicine ; it goes a long way to redress the balance.

There were 844 men who had a diagnosis of localized prostate cancer in Geneva, Switzerland, between 1989 and 1998. Of these, 158 had a prostatectomy, 205 had radiotherapy, 378 underwent watchful waiting, 72 had hormone therapy, and 31 had other types of therapy. Survival curves were prepared for the different types of management.

5-year mortality was similar among the different treatment groups, but the 10-year analyses showed clear-cut changes. 10-year survival was 83% for surgery, 75% for radiation, 72% for watchful waiting. The increased mortality for radiation and watchful waiting was seen chiefly inpatients under 70 and in those with poorly-differentiated tumors on pathological exam.

This 'observational' study has limitations that are fairly obvious - lack of randomization to treatment being the main one. But prospective randomized studies are virtually impossible in cancer trials where surgery, radiation or waiting are the options. We must rely on post-hoc analyses of this nature, with the results carefully adjusted for possible biasing factors, such as age, ethnicity, degree of tumor differentiation, and so on. The role of vitamin D in prostate cancer survival is an example of a factor that should be further evaluated. Or the effect of post-surgical androgen deprivation therapy ...