Transurethral resections (TUR) and totally embedded radical prostatectomies from 39 clinical Stage A2 prostate cancers were morphometrically analyzed and compared with 56 prior similarly studied clinical Stage B cancers. All the clinical A2 radical prostatectomies contained residual tumor with 26% having capsular penetration. Clinical Stage A2 tumors were much more heterogeneous than clinical Stage B tumors with respect to tumor location, grade, and amount. In particular, many clinical A2 cases were predominantly central or central and anterior in location (59%) and low-grade compared with clinical Stage B cases where most lesions were posterior, peripheral, and intermediate grade. Percent of tumor in TUR best predicted final pathologic stage versus TUR grade or volume. Despite statistically significant correlations between tumor percent and/or grade on TUR and final stage, predictability of final stage for individual patients from TUR data was poor. The complex interrelation of tumor location, grade, and amount resulted in wide and overlapping ranges for these parameters for organ-confined and nonconfined cases.