Successful radiotherapy in postoperative recurrence of a primary mediastinal yolk sac tumor: A case report

A woman in her 60s was evaluated for anterior chest pain. Computed tomography (CT) revealed a 50 mm mass with irregular contrast enhancement in the anterior mediastinum. α‐fetoprotein (AFP) level was elevated to 1188 ng/mL. A germ cell tumor was diagnosed, mostly comprising of a yolk sac tumor (YST). Two courses of chemotherapy with cisplatin (CDDP) and etoposide (VP16) were administered and surgical tumor resection was then performed. The final diagnosis was YST. CDDP and VP16 were continued postoperatively; however, because the AFP level increased about six months after surgery, the chemotherapy regimen was altered to bleomycin and CPT‐11. As the AFP again increased and a CT scan revealed tumor re‐enlargement, recurrent YST was diagnosed and radiotherapy was administered. The patient received a total of 60 Gy (2 Gy per fraction). The tumor started to shrink during radiotherapy and AFP levels decreased. By one month post‐radiotherapy, AFP levels had normalized and the tumor had disappeared. As of six years after radiotherapy, the patient remains alive without recurrence. Mediastinal YSTs are rare, and treatment usually includes surgery and preoperative and postoperative chemotherapy with cisplatin‐based regimens. Successful treatment with radiotherapy has occasionally been reported. Our patient showed recurrence of a YST after surgery and chemotherapy, but achieved long‐term survival after radiotherapy. Few patients with YST have undergone radiotherapy, but this approach was successful in our patient. In cases of postoperative recurrent YST resistant to chemotherapy, radiotherapy, together with salvage surgery, may offer a valuable option.