To compare the outcomes between patients with stage T1a/b with those of patients with T1c cancer of the prostate treated with radical retropubic prostatectomy (RRP), as the appropriate management of clinical stage T1a/b prostate cancer is subject to debate; although many patients are managed expectantly, some have adverse pathological features suggesting that more active treatment might be beneficial. From 1983 to 2003, 3478 men had RRP by one surgeon. From this group, we retrospectively identified 29 men with clinical stage T1a and 83 with clinical stage T1b disease. Using statistical analysis we compared the treatment outcomes of these patients with those of 1774 men with clinical stage T1c disease. Men with T1a/b disease had a significantly lower preoperative prostate-specific antigen (PSA) level, a greater proportion with organ-confined disease, and a lower mean/median prostatectomy Gleason score than those with T1c disease. Also, men with T1a/b disease were less likely to be potent before surgery, although the frequency of recovery of potency was similar among all groups. On multivariate analysis with age, year of surgery, PSA level and Gleason score, there was no statistical difference in the rates of biochemical recurrence and the 10-year overall survival rates. However, patients with T1b disease had a significantly lower cancer-specific survival. T1a and T1b prostate cancer can be associated with aggressive pathological features and have a similar rate of progression as clinical stage T1c disease. That notwithstanding, most patients in the study were cured with RRP and had favourable long-term functional outcomes.