Sertoli–Leydig cell tumour

Sertoli–Leydig cell tumour is a group of tumors composed of variable proportions of Sertoli cells, Leydig cells, and in the case of intermediate and poorly differentiated neoplasms, primitive gonadal stroma and sometimes heterologous elements. The tumor secretes testosterone. It is a member of the sex cord-stromal tumour group of ovarians and testicular tumors.

The tumour mainly occurs in early adulthood (not seen in newborn), is rare, comprising less than 1% of testicular tumours. While the tumour can occur at any age, it occurs most often in young adults.

The tumour is even rarer in the ovary, comprising less than 0.5% of ovarian tumors. It mainly occurs in early adulthood, specifically the second and third decades of life. 2011 studies have shown that many cases of Sertoli–Leydig cell tumor of the ovary are caused by germline mutations in the DICER1 gene. These hereditary cases tend to be younger, often have a multinodular thyroid goiter and there may be a personal or family history of other rare tumors such as pleuropulmonary blastoma, Wilms tumor and cervical rhabdomyosarcoma.

Closely related terms include arrhenoblastoma and androblastoma. Both terms are classified under Sertoli–Leydig cell tumour in MeSH. The word stems arrheno- and andro- both mean "male".