Prostate elastosis - A microscopic feature useful for the diagnosis of postatrophic hyperplasia

Background.-Elastosis of the prostate may be seen on needle biopsy and radi cal prostatectomy specimens, but its significance is unknown. Prostatic atr ophy (or postatrophic hyperplasia) is one of the most frequent mimics of pr ostatic adenocarcinoma. Objective.-To observe the frequent occurrence of elastosis of the prostate stroma in areas of postatrophic hyperplasia. Design.-A step-section method was used to cut the posterior lobe (or periph eral zone) in coronal planes at intervals of 0.3 to 0.5 cm in 100 consecuti ve autopsy specimens of men older than 40 years. Elastosis was detected bec ause of a basophilic tinge of the stroma on hematoxylin-eosin stain and con firmed using elastic fiber stains. Presence of elastosis correlated with th e following variables: age, prostatic atrophy (simple, hyperplastic, or scl erotic), local arteriosclerosis, histologic carcinoma, high-grade prostatic intraepithelial neoplasia, benign or malignant nephrosclerosis, generalize d atherosclerosis, nodular prostatic hyperplasia, and acute inflammation. F or statistics, a stepwise linear regression method adjusted for age was use d. Results and Conclusions.-Elastosis was found in 65 of the prostates examine d and was significantly more frequent with increasing age (P < .001), prost atic atrophy (P < .001), and local arteriosclerosis (P < .02). There was no significant relation to histologic carcinoma, high-grade prostatic intraep ithelial neoplasia, benign or malignant nephrosclerosis, generalized athero sclerosis, nodular prostatic hyperplasia, and acute inflammation. The corre lation with local arteriosclerosis favors a possible role of ischemia to it s etiopathogenesis. The absence of correlation to neoplastic and preneoplas tic lesions and the striking spatial relationship of elastosis to prostatic atrophy (or postatrophic hyperplasia) add a new microscopic feature for th e diagnosis of this latter lesion, helping in the differential diagnosis wi th prostate adenocarcinoma.