We have already pointed out by the use of multivariate analysis that local response of the prostate is one of the important prognostic factors in patients receiving endocrine therapy. Herein, we investigated how the local response to endocrine therapy affects the survival rate or the survival period. We also studied the relationship between the local response and histopathological findings. The local response of prostate was not correlated with the stage progression. Sixty-seven percent of the patents in each stage had an initially favorable local response of the prostate, in which the primary tumor became flattened or reduced by endocrine therapy. By contrast, the local response of the prostate was well correlated with the prognosis in each stage. Patients with a flattened or reduced primary lesion following endocrine therapy showed a higher survival rate or a longer survival period than those with the unchanged lesion. This result has confirmed that the local response of prostate to endocrine therapy is useful in predicting clinical courses of patients. Grade of structural atypism (SAT), one of the pathological findings, had a correlation with local response of the prostate. With an elevation of the SAT grade, the proportion of patients with unchanged primary lesion was increased.