Cytologic identification of reinke crystalloids in scrapings and imprints of fresh testicular tumors: a simple and rapid technique for intraoperative use.

Although not required for the diagnosis, crystalloids of Reinke are pathognomonic for Leydig cell tumor. However, conventional frozen section rarely reveals their presence. A method of rapid identification of crystalloids of Reinke could improve the intraoperative diagnosis. We tested the efficacy of touch imprints and scrape smears for the identification of crystalloids in 2 cases of Leydig cell tumor of the testis. Intraoperative smears of the tumors yielded abundant crystals. Scrape cytologic testing was the better method. We speculate that the process of scraping, and to a lesser extent touch imprinting, disrupts the cytoplasm of the Leydig cells and releases the crystalloids. We conclude that cytologic testing is an effective method of identifying crystalloids of Reinke in Leydig cell tumors of the testis.