USE SF ENDORECTAL MR-IMAGING TO PREDICT PROSTATE CARCINOMA RECURRENCEAFTER RADICAL PROSTATECTOMY

Purpose: To determine the ability of endorectal magnetic resonance (MR ) imaging to help predict postprostatectomy disease recurrence and, th ereby, patient outcome. Materials and methods: The authors evaluated 1 16 patients for prostate MR imaging during 1991 and 1992 who subsequen tly underwent radical prostatectomy and for whom follow-up data throug h 1996 could be obtained. The MR reports, clinic charts, and pathology reports were reviewed. Disease recurrence was established by means of detectable levels or serum prostate-specific antigen (PSA) after surg ery. Results: Thirty-four patients (29%) had postoperative disease rec urrence. Patients with recurrence had higher preoperative PSA values ( P < .0001). These patients also more frequently had positive surgical margins (P = .0005), transcapsular tumor spread (P <. 001) and high gr ade (P = .0058). Of 13 patients whose MR examinations showed definite extracapsular disease, eight (65%) had disease recurrence. The recurre nce rate when MR imaging indicated limited disease (24%) was similar t o that when MR imaging showed possible microscopic extension (27%). An MR finding of definite extracapsular disease was 24% sensitive and 94 % specific for the prediction of disease recurrence. Conclusion: MR im aging findings of definite extracapsular spread of disease helped pred ict prostate tumor recurrence with high specificity, although with low sensitivity.