Leydig Cell Tumor (Testicular)

A Leydig Cell Tumor (Testicular) is a rare growth that develops in the testicles, which are part of the male reproductive system. These tumors arise from the Leydig cells, which normally produce the hormone testosterone. When a tumor forms, it can cause an imbalance in hormone levels, leading to symptoms like enlarged testicle, breast enlargement, or changes in sexual development. This condition mainly affects hormone production and can sometimes cause pain or swelling in the scrotum. Although most Leydig cell tumors are benign, some can be malignant and require medical evaluation.

Leydig Cell Tumor (Testicular) is a rare sex cord-stromal tumor originating from the Leydig cells of the testicular interstitium, which are responsible for androgen production. These tumors typically present in adult males but can also occur in children, often causing precocious puberty due to excess testosterone secretion. The pathogenesis involves uncontrolled proliferation of Leydig cells, sometimes linked to activating mutations in the LH receptor or other molecular pathways. Clinically, patients may present with a painless testicular mass, hormonal symptoms such as gynecomastia or infertility, and occasionally signs of malignancy. Histologically, the tumor is characterized by large polygonal cells with eosinophilic cytoplasm and Reinke crystals. The major clinical significance lies in its potential for hormone secretion and rare malignant transformation.