Clinical and pathological staging furnishes valuable information upon which the clinician can base his treatment and compare results. Staging refinements occur as we learn more about the natural history of the disease and the efficacy of our treatment. We observed that clinical stage B patients with minimal (less than twice normal) elevation of the serum acid phosphatase have similar pathologic stage B (75%) and disease-free survival rates following total prostatectomy as stage B patients with normal acid phosphatases. Intraglandular crystalloids were found in 26% of clinical stage B patients treated by total prostatectomy, and none of this subgroup of patients has had a recurrence of disease. Pathologic staging frequently confirms the presence of a greater extent of tumor than was clinically anticipated. In general, prognosis for patients with a small tumor mass will be more favorable than that for patients with a large tumor mass. Staging permits the estimation of prognosis of groups of patients with similar tumor burdens; however, the survival of an individual within any such group is unpredictable.