testicular sex cord-stromal neoplasm (Monarch Disease Ontology identifier MONDO_0003125) is a benign or malignant tumor that arises from the testis. It is composed of granulosa cells, Leydig cells, Sertoli cells, and fibroblasts. Each of these cell types may constitute the only cellular component that is present in the tumor or it may be mixed with other cell types in various combinations. The prognosis can not always be predicted on histologic grounds alone. Approximately, ten percent of these tumors may metastasize. Representative examples include granulosa cell tumor, Leydig cell tumor, Sertoli cell tumor, and tumors of the thecoma-fibroma group. Also known as: sex cord-stromal tumor of testis, sex cord-stromal tumour of testis, testicular sex cord-stromal tumor, testicular sex cord-stromal tumour, testis sex cord-stromal tumor, testis sex cord-stromal tumour.