It is inevitable; most men with prostate cancer, who require treatment with androgen deprivation therapy (ADT), will eventually become resistance to treatment leading to the development of metastatic disease. Men who develop metastatic castrate-resistant disease have a very poor prognosis. Historically, their overall survival is estimated only to be 24 to 36 months.

A study at the Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio tried to identify predictors of clinical disease progression in patients with prostate cancer who were receiving ADT.

They evaluated 13,740 men with biopsy-confirmed prostate cancer who were enrolled in the Cancer of the Prostate Strategic Urological Research Endeavor (CaPSURE) database from 1995 to 2007. The primary endpoint of the study was the development of bone metastasis. They compared clinical and pathologic characteristics between men who developed metastasis and those who did not using chi-square tests in a Cox proportional hazards regression model.

The mean age of the 13,740 men was 70 years, with a range of 39-94 years. One hundred ninety-one men (4.8%) progressed to metastatic disease at a median of 18 months from the initiation of ADT (range, 1-139 months). On multivariate analyses, risk category (hazards ratio