Abstract Purpose The pathological characteristics of stage T1c cancers in the era of widespread prostate specific antigen (PSA) testing were determined, and the ability of pretreatment parameters to predict tumor significance in men with stage T1c disease was evaluated. Materials and Methods Of 336 men with stage T1c prostate cancer seen between 1994 and 1996, 240 (71.4%) were treated with radical prostatectomy, 20 (6%) with radiation therapy and 76 (22.6%) expectantly. Recommendations for treatment were based on previously determined criteria predictive of a significant stage T1c cancer (more than 0.2 cm. 3): 1) PSA density 0.15 ng./ml./gm. or more, 2) Gleason score 7 or greater, 3) 3 or more cores involved with cancer, or 4) 50% or more involvement of any core with cancer. Pathological evaluation of prostatectomy specimens allowed classification of tumors as insignificant (confined tumor smaller than 0.2 cm. 3 with a Gleason score of less than 7), minimal (confined tumor 0.2 to less than 0.5 cm. 3 with a Gleason score of less than 7), moderate (0.5 cm. 3 or larger disease, or capsular penetration with a Gleason score of less than 7) and advanced (capsular penetration with a Gleason score of 7 or more, or positive margins, seminal vesicles or lymph nodes). Pathological characteristics of tumors in this series were compared to a previous series of 157 men with stage T1c cancers who underwent radical prostatectomy between 1988 and 1992. Results Of 240 men who underwent radical prostatectomy tumors were insignificant in 40 (17%), minimal in 29 (12%), moderate in 124 (52%) and advanced in 47 (19%). An increase in organ confined cancers (51 to 72%) and a decrease in positive margins (17 to 8%) were noted when comparing stage T1c series (1988 to 1992 versus 1994 to 1996) but the percentage of insignificant tumors remained stable (16 versus 17%) between series. Ultrasound and sextant biopsies were available for review in 72 cases (current series). If the pretreatment criteria used to recommend therapy suggested significant tumor (64 cases) then insignificant tumor was present in only 10 (16%). If pretreatment criteria suggested insignificant tumor (8 cases), insignificant or minimal tumor was present in 6 (75%) and moderate organ confined disease was present in 2 (25%). The absence of a lesion on ultrasound and measurement of total length of cancer within the biopsy specimen were not predictive of an insignificant tumor. Conclusions In a nonscreened population stage T1c cancers are being discovered earlier with widespread PSA testing. Even with the detection of earlier cancers we demonstrated that it is possible to minimize the number of patients with small tumors who will undergo radical prostatectomy using pretreatment criteria to counsel men regarding appropriate management options.