The patient was a 27-year-old male. In December 2020, he was diagnosed with a primary extragonadal germ cell tumor of the retroperitoneum with inferior vena caval (IVC) involvement. After 3 courses of bleomycin, etoposide and cisplatinum and 3 courses of paclitaxel, ifosfamide and cisplatin, the serum human chorionic gonadotropin (hCG) level remained abnormally low. He was referred to our department after follow-up for 2 months. Since the hCG level continued to decrease during follow-up, we decided to perform marker-positive surgery. He underwent retroperitoneal lymph node dissection. We also resected a part of the IVC wall and tumor in the IVC. The serum hCG level was normalized at 5 days after surgery. Pathological examination revealed only necrotic tissue. Immunohistochemistry showed hCG positive in the necrotic tissue.