Leydig cell neoplasia in a patient with Reifenstein syndrome.

We present the rare coincidence of a Leydig cell tumor in both testicles of a patient with partial androgen insensitivity syndrome (PAIS). The clinical picture with perineoscrotal hypospadia, micropenis, gynecomastia and delayed puberty and the serum hormone levels with elevated concentrations of testosterone, luteinising hormone (LH) and follicle-stimulating hormone were entirely consistent with PAIS. Ultimately, the diagnosis was confirmed by determination of genital skin fibroblast androgen receptor binding capacity for 5 beta-dihydrotestosterone, which demonstrated a qualitatively abnormal androgen receptor. At 44 years of age, a nodule in the left testis led to orchidectomy. At that time, the right testis was inconspicuous sonographically. But 3 years later the right testis developed nodules and was removed. Review of testicular histology revealed the presence of Leydig cell hyperplasia (LCH), multifocal nodular hyperplasia and Leydig cell neoplasia (LCN) in both testes. Many micronodules of Leydig cells in transition from hyperplasia to neoplasia were also identified. The simultaneous development of histologically identical nodes of LCN independently from each other and a different sites of both tests indicates the presence of a tumorigenic factor acting on the Leydig cells. Furthermore, the observation of multiple foci of cells in all stages of transition from hyperplasia to neoplasia demonstrates the persistent process of transformation. We speculate, that in this patient the grossly elevated LH levels present over 30 years have enhanced, if not provoked, the formation of LCN. In addition, the defective androgen receptor might have prevented suppressive effects of androgens on the Leydig cells.