title: Metachronous development of malignant Leydig cell tumor.
abstract: Leydig cell tumor (LCT), a rare testicular tumor, is malignant in only about 10% of the cases. We report the case of a patient with bilateral malignant LCTs that developed metachronously. After undergoing a right inguinal orchiectomy for a malignant LCT at the age of 43 years, the patient was given cisplatin-based chemotherapy for suspected para-aortic lymph node metastasis. Eighteen months after the right orchiectomy, examination of a left testicular biopsy specimen showed a malignant LCT and a left inguinal orchiectomy was performed. Histologically, the initial malignant LCT exhibited a highly pleomorphic appearance with mitotic figures (58/10 HPF), whereas the second malignant LCT showed fewer mitoses (2/10 HPF). The proliferating cell nuclear antigen (PCNA)-labelling index in these tumors also differed (right-sided tumor, 50%; left-sided tumor, 28%). These findings suggest that the malignant LCT in the left testis developed as a second primary rather than as a metastatic tumor. There have been no known similar cases, although three cases of malignant LCT with contralateral metastasis have been reported.
authors.affiliation: Department of Pathology, Iwate Medical University School of Medicine, Morioka, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Sugimura
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: G
authors.initials: G
authors.lastname: Tamura
authors.forename: H
authors.initials: H
authors.lastname: Funaki
authors.forename: T
authors.initials: T
authors.lastname: Fujioka
authors.forename: R
authors.initials: R
authors.lastname: Satodate
mesh_terms: D000328:Adult; D006801:Humans; D007150:Immunohistochemistry; D007984:Leydig Cell Tumor / Q000737:chemistry / Q000473:pathology*; D008297:Male; D016609:Neoplasms, Second Primary / Q000737:chemistry / Q000473:pathology*; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D013736:Testicular Neoplasms / Q000737:chemistry / Q000473:pathology*
chemical_list: D018809:Proliferating Cell Nuclear Antigen