A case of testicular cancer with retroperitoneal lymph node metastasis of teratoma with somatic-type malignancy 18 years after initial treatment.

Late relapse of teratoma with somatic-type malignancy was resected by laparoscopic retroperitoneal lymph node dissection. Therefore, long-term follow-up should be considered if patients with small retroperitoneal masses did not undergo retroperitoneal lymph node dissection, and early detection and surgical resection for relapse might be effective.