Pulmonary metastasis from adult-type granulosa cell tumor of the testis: a rare case report and literature review

Although adult-type granulosa cell tumor of the testis is generally indolent, some cases may behave aggressively. Tumor size, vascular invasion, and proliferative index may correlate with metastatic potential. Patients who undergo complete resection of metastatic lesions tend to achieve better outcomes, whereas responses to systemic therapy are generally poor. Early identification of high-risk features and consideration of retroperitoneal lymph node dissection may improve prognosis in selected patients.