Can the core length involved with prostate cancer identify clinically insignificant disease in low risk patients diagnosed on the basis of a single positive core?

Clinically insignificant prostate cancer, defined as at most microscopic foci of Gleason grade < or = 3 disease in the radical prostatectomy specimen, has been recognized in some low risk (PSA < 10, biopsy Gleason score < or = 6, clinical Tlc, 2a) patients with minimal biopsy cancer volume. The purpose of this study is to determine if the fraction of cancer in a single positive core biopsy could identify a subset of low risk prostate cancer patients with clinically insignificant disease. Of 1100 patients with Tlc,2 prostate cancer that consecutively underwent radical prostatectomy at Brigham and Women's Hospital between 1989 to 2000, 130 low risk patients whose diagnoses were made on the basis of a single positive core comprised the study cohort.

Percentage of core lengths involved with prostate cancer: does it add to the percentage of positive prostate biopsies in predicting postoperative prostate-specific antigen outcome for men with intermediate-risk prostate cancer?

Objectives: To evaluate whether the percentage of core lengths involved with prostate cancer added clinically significant information concerning the time to postoperative prostate-specific antigen (PSA) failure in the intermediate-risk patient beyond what is provided by the percentage of positive biopsies.

Methods: Cox regression multivariable analysis was performed to compare the ability of the two measurements of biopsy cancer volume to predict the time to PSA failure from a series of 184 surgically treated intermediate-risk patients. PSA outcome was estimated using the actuarial method of Kaplan and Meier, and comparisons were made using the log-rank test.