Peripheral Precocious Puberty in a Male Caused by Leydig Cell Adenoma Harboring a Somatic Mutation of the LHR Gene: Report of a Case
Surasak Sangkhathat MD, PhD*,**, Samornmas Kanngurn MD*,***, Somchit Jaruratanasirikul MD****, Teeravut Tubtawee MD*****, Walawee Chaiyapan MS*, Sakda Patrapinyokul MD**, Piyawan Chiengkriwate MD**
Affiliation : * Tumor Biology Research Group, Faculty of Medicine, Prince of Songkla University, Hat yai, Songkhla, Thailand ** Department of Surgery, Faculty of Medicine, Prince of Songkla University, Hat yai, Songkhla, Thailand *** Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat yai, Songkhla, Thailand **** Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Hat yai, Songkhla, Thailand ***** Department of Radiology, Faculty of Medicine, Prince of Songkla University, Hat yai, Songkhla, Thailand
While a germline activating mutation of the luteinizing hormone receptor (LHR) gene is known to cause autonomous production of testosterone from testicular Leydig cells in male-limited precocious puberty, only a few studies have addressed the role of somatic LHR mutation in testicular pathology. The authors report a case of a 6-year-old boy who developed secondary sex characteristics including facial acne, enlarging genitalia, and aggressive behavior, for which serial biochemical evaluation confirmed the status of peripheral precocious puberty. Examination revealed asymmetrical testicular volume, following which a left testicular tumor was detected through ultrasonography. A left orchiectomy was performed, and histopathology revealed a well-circumscribed Leydig cell tumor. Molecular study of the exon 11 of the LHR gene revealed a missense mutation at the nucleotide position 1,732, leading to a substitution of histidine for aspartic acid at codon 578. Interestingly, the substitution was consistent with all previously reported LHR alteration in pediatric Leydig cell adenoma, but which had never before been reported in male-limited precocious puberty, suggesting that the mutation is a molecular signature of the adenoma.
Keywords : Pediatric Leydig cell tumor, Luteinizing hormone receptor, LHR
