IS TUMOR VOLUME AN INDEPENDENT PREDICTOR OF PROGRESSION FOLLOWING RADICAL PROSTATECTOMY - A MULTIVARIATE-ANALYSIS OF 185 CLINICAL STAGE-B ADENOCARCINOMAS OF THE PROSTATE WITH 5 YEARS OF FOLLOW-UP

Tumor volume has been shown to be proportionate to Gleason grade, caps ular penetration, seminal vesicle invasion, lymph node metastases and capsular margins of resection. Because these variables are often inter related, it is crucial to determine which of these parameters provides independent prediction of prognosis in prostate cancer. The current s tudy analyzed 185 men who underwent radial retropubic prostatectomy fo r clinical stage B adenocarcinoma of the prostate. Patients with semin al vesicle invasion or lymph node metastases were excluded, since thes e findings are almost invariably associated with progression. All pati ents were followed for a minimum of 5 years after radical prostatectom y. Only 2 men received postoperative adjuvant therapy. At 5 years afte r radical prostatectomy 58 men (31%) experienced progression, defined by either an elevated postoperative serum prostate specific antigen le vel, local recurrence or distant metastases. Although by themselves ca psular penetration, tumor volume and per cent of the prostate involved by tumor predicted progression, in a stepwise regression analysis the y did not provide independent prognostic information. In this multivar iate analysis Gleason score was the best predictor of progression (p < 0.0001); surgical margin was the only other variable that enhanced pre diction, although it was less influential than grade (p = 0.018). This strong predictability provided by Gleason score was all the more impr essive given the relatively few patients in our study with either low or high grade tumor. Although an accurate preoperative assessment of t umor volume remains desirable for the management of patients with pros tate cancer, our study demonstrates that measurement of tumor volume i n radical prostatectomy specimens need not be performed as part of the routine pathological analysis of radical prostatectomy specimens, sin ce it does not provide additional information beyond that of Gleason s core and the status of capsular margins.