Expectant management of localized prostatic cancer. Seventy-five patients with clinical Stage B histologically proven prostatic cancer accumulated over a 40-year period and receiving no therapy for at least 1 year after histologic diagnosis were retrospectively reviewed. Twenty-nine patients had Stage B1 lesions, 37 had B2, and nine had B3 lesions; median follow-up for these patients was 124, 120, and 96 months, respectively. Five ultimately received pelvic lymph node dissection with iodine-125 implantation, 23 had transurethral resection of the prostate, and 18 had endocrine therapy. Of those tumors which progressed, 18 of 19 (95%) B1, 26 of 29 (90%) B2, and four of four (100%) B3 lesions demonstrated local progression first. Six of 29 (21%) B1, 17 of 37 (46%) B2, and two of nine (22%) B3 tumors developed recognized distant metastasis. Actuarial survival at 15 years was 67%, 39%, and 63% for patients with B1, B2, and B3 lesions, respectively. These data indicate the varied and potentially protracted course of patients with clinical Stage B prostatic cancer. 