Leydig cell tumour, also Leydig cell tumor (US spelling), (testicular) interstitial cell tumour and (testicular) interstitial cell tumor (US spelling), is a member of the sex cord-stromal tumour group of ovarian and testicular cancers. It arises from Leydig cells. While the tumour can occur at any age, it occurs most often in young adults.
A Sertoli–Leydig cell tumour is a combination of a Leydig cell tumour and a Sertoli cell tumour from Sertoli cells.
The majority of Leydig cell tumors are found in males, usually at 5–10 years of age or in middle adulthood (30–60 years). Children typically present with precocious puberty.
Due to excess testosterone secreted by the tumour, one-third of female patients present with a recent history of progressive masculinization. Masculinization is preceded by anovulation, oligomenorrhea, amenorrhea and defeminization. Additional signs include acne and hirsutism, voice deepening, clitoromegaly, temporal hair recession, and an i