Pathological Characteristics and Prognosis of Nonpalpable and Palpable Prostate Cancers with a Hybritech Prostate Specific Antigen of 4 to 10 ng./ml

PURPOSE: We compared the surgical pathological findings and postoperative course of patients with palpable and nonpalpable prostate cancers. MATERIALS AND METHODS: All patients with untreated prostate specific antigen (PSA) 4 to 10 ng./ml. who underwent radical prostatectomy between December 1984 and December 1993 were reviewed to select 61 with clinical stage T1c (nonpalpable) with stages T2a to c (palpable) disease. RESULTS: Nonpalpable cancers were smaller (2.99 versus 4.42 cc for palpable tumors), had smaller volumes of Gleason grade 4 to 5 cancer (0.66 versus 1.32 cc, respectively) and were less likely to have positive surgical margins (13 versus 22%, respectively) or significant (1 cm. or more) capsular penetration (10 versus 26%, respectively). Nonpalpable and palpable cancers had similar rates of seminal vesicle invasion (3.3 versus 4.3%, respectively) and positive lymph nodes (1.6 versus 0%, respectively). More than 90% of patients with nonpalpable cancer were biochemically cancer-free postoperatively, and the remainder were alive with disease after a mean followup of 25.1 months, compared to 69% disease-fee, 28% alive with disease and 2.5% dead of prostate cancer after mean followup of 43.8 months among those with palpable disease. CONCLUSIONS: We conclude that nonpalpable prostate cancers are pathologically more favorable than palpable prostate cancers with PSA 4 to 10 ng./ml. Our preliminary results also indicate that nonpalpable cancers are less likely to recur postoperatively than palpable cancers with a similar PSA range.