Bilateral corpus cavernosum thrombosis revealing penile synovial sarcoma.

Corpus cavernosum thrombosis is rare, and its association with penile malignancy is exceptionally uncommon. Although most penile cancers are squamous cell carcinomas, primary synovial sarcoma is exceedingly rare. We report a 36-year-old man with bilateral corpus cavernosum thrombosis and persistent perineal pain, managed conservatively for two years, during which imaging failed to identify a neoplasm. He later developed a rapidly enlarging penile mass with nodal involvement; total penectomy with lymphadenectomy confirmed synovial sarcoma. Early recurrence with metastatic progression required palliative therapy, and he died eight months postoperatively. Persistent or unexplained corpus cavernosum thrombosis should prompt consideration of malignancy.