Changes in extent and zonal distribution of prostatic adenocarcinoma in patients preoperatively treated with neoadjuvant endocrine therapy: Analysis on whole-mounted prostatectomy specimens

BACKGROUND: An increasing number of pharmacologic agents that induce reversible androgen deprivation are available for neoadjuvant endocrine therapy (NET) for prostatic adenocarcinoma (PCA). If information about the regression pattern of PCA after NET is recognized, more effective decision-making for subsequent therapies such as prostatectomy and radiotherapy, will be possible. METHODS: The extent and zonal distribution of PCA with or without NET were examined in totally embedded radical prostatectomy specimens obtained from 103 patients with PCA. Seventy-nine of the 103 patients received androgen deprivation therapy (castrated). The zonal location of PCA lesions (non-transition vs transition zone), was identified in three slices from the inferior, middle and superior parts of the prostate. The area of the PCA lesions in these zones was measured. RESULTS: Prostatic adenocarcinoma was identified in 94 of 103 cases: 24 of 24 cases (100%) and 70 of 79 cases (87%) in the non-castrated and castrated groups, respectively. The NET induced a mean of 21% reduction of the prostate volume and lowered the serum PSA level by one eighth. The frequency of capsular penetration in the castrated cases (57%) was lower than in the non-castrated cases (83%) and confinement of the PCA lesion was found in 32% of the castrated and 17% of the non-castrated cases. The reduction rate of the extent of the PCA lesions in the non-transition and transition zone was 33% and 28%, respectively. The extent of the PCA lesions were smaller in the anterior parts, especially at the superior portion of the prostate. CONCLUSION: Neoadjuvant endocrine therapy induced involutional changes of the PCA evenly across both the non-transition and transition zones. The density of the PCA lesions was low in the anterior part of the prostate. This information is useful for decision-making in post-NET.