Leydig cell tumor sex cord-stromal benign neoplasm benign Leydig cell tumor Leydig cell tumor, benign A Leydig cell tumor which does not recur or metastasize. Morphologically, there is no evidence of cellular atypia, increased mitotic activity, necrosis, or vascular invasion. MONDO:0036990 benign interstitial cell tumor benign interstitial cell tumour MEDGEN:83142 NCIT:C4212 ICDO:8650/0 benign Leydig cell neoplasm adenoma, interstitial benign Leydig cell tumor benign interstitial cell neoplasm UMLS:C0334409