Purpose: We compare clinicopathological features, and cancer recurrence and survival rates in men with stage T1c versus T2a or T2b prostate cancer.
Materials and methods: From 1988 through 1998, 1 surgeon (W. J. C.) performed radical retropubic prostatectomy in 1,620 men with a mean age plus or minus standard deviation of 62.3 +/- 7 years. Clinical stage was T1c in 39%, T2a in 22% and T2b in 39% of patients. Patients were followed with semiannual prostate specific antigen (PSA) measurement and annual digital rectal examination. Serum total PSA greater than 0.3 ng./ml., histologically confirmed local tumor recurrence or distant metastases were considered evidence of cancer recurrence. Simple univariate statistics were used to compare clinical and pathological features by clinical stage, and multivariate Cox models were used to compare 5-year recurrence-free probabilities . The 5-year all cause and disease specific survival rates were calculated using Kaplan-Meier product limit estimates.
Results: Mean patient age was younger for the clinical stage T1c group (61 years) than for the T2a (62 years) or T2b (64 years) group. Mean preoperative PSA and the percentage of patients with biopsy Gleason score 8 to 10 were more favorable for the T1c (8 ng./ml., 3%) and T2a (7, 5%) groups than for the T2b group (11, 6%). Cancerous surgical margins, seminal vesicle invasion and lymph node metastases were also less frequent in the T1c (20, 5 and 0.8%, respectively) and T2a (23, 5 and 0.3%) groups than in the T2b group (29, 11 and 1.8%). The 5-year recurrence-free survival rate was 85% for T1c, 83% for T2a and 72% for T2b cases. Multivariate analysis indicated a decreased risk of recurrence for the T1c group compared to the T2a and T2b groups. The 5-year disease specific survival rate was 100% for the T1c and T2a groups, and 97% for the T2b group.
Conclusions: Clinical and pathological features were similar for stages T1c and T2a, and different from stage T2b cancers. The 5-year recurrence-free survival was similar for T1c and T2a (log rank 0.89, p = 0.34), and higher than that for T2b (log rank 34.5, p <0.0001) cancers. However, controlling for all other prognostic factors on a Cox multivariate model, the risk of cancer recurrence was decreased for T1c compared to T2a and T2b disease. The detection of nonpalpable prostate cancer appears to be advantageous for intermediate-term cancer control.