Two Cases of Primary Mediastinal Yolk Sac Tumor, Successfully Treated with Preoperative Chemotherapy

The first case was a 24 year-old male who complained of anterior chest pain. On admission, chest X-ray and CT scan showed a huge tumor mass in the right anterior mediastinum, and the tumor infiltrated surrounding tissues. Serum α-fetoprotein (AFP) was 6387ng/ml. Needle biopsy suggested a yolk sac tumor. Combination chemotherapy with cisplatin (CDDP), etoposide (VP-16) and bleomycin (BLM) obtained partial remission (29% reduction in the bidimensional tumor size) and serum AFP also decreased to 922ng/ml. The tumor was completely removed with en-bloc resection of the right lung and pericardium. Pathological findings of the resected tumor showed eosinophilic hyaline bodies, Schiller Duval bodies and AFP-positive tumor cells. Postoperative chemotherapy with the same regimen was administered. The patient is alive and well, 3 years after operation and serum AFP is within normal levels. The second case was a 30 year-old male who complained of pain in the left neck and anterior chest.Roentgenological examination showed a huge tumor mass in the anterior mediastinum and bilateral lung metastases. CT scan showed the tumor to be heterogeneous in density. The serum AFP level was 1406ng/ml. Needle biopsy yielded a histologic diagnosis of yolk sac tumor. After CDDP-based combination chemotherapy and radiation therapy, the tumor size reduced to some extent and the shadows suggesting lung metastases disappeared completely. On chest CT, the density of the tumor changed to a homogeneous pattern and serum AFP decreased to a normal level. The tumor was then removed completely and pathological findings of the tumor showed manifest necrosis but some viable tumor cells. Two cycles of postoperative chemotherapy with a similar regimen were administered. The patient had no relapse and is alive 7 months after the operation.Serum AFP is within the normal range.