We investigated how histopathological features, such as structural atypism (SAT), nuclear anaplasia (NAN) and Gleason's pattern, influence the prognosis of patients receiving endocrine therapy. Patients with SAT 3 or NAN 3 clearly had a lower survival rate and a shorter survival period than those with other grades of SAT or NAN and this tendency was more prominent in the high stage than low stage. Patients with a higher grade of SAT or NAN had a poorer prognosis as well, when only cancer-related death was considered in the calculation of survival and survival period. The results described above suggest that the grade of SAT and NAN is one of most influential factors for prognosis. In the analysis for the prognosis of patients according to grade of mean value of SAT + NAN, there were differences in prognosis among mean value of SAT + NAN 2-4, 5 and 6. This indicated that the combined grading system would provide more information to the prediction of prognosis. Patients with Gleason's primary (or secondary) pattern 1 and 2, or 3 and 4 had a better survival than those with pattern 5 in the analysis when only cancer-related death was considered. This was coincident with the result that the survival rate for each Gleason's sum 2-3, 4-5, 6, 7-8 and 9-10 was different. Consequently, Gleason's pattern influenced the rate of cancer-related deaths, and this pattern may be another important factor for predicting the prognosis.