Purpose: We defined the growth rate and reviewed our experience in the surgical management of growing teratoma syndrome in patients with nonseminomatous germ cell tumors.
Materials and methods: Nine patients were clinically diagnosed with growing teratoma syndrome at our center from 1980 to 2003. The defining criteria of growing teratoma syndrome were growing metastatic mass in the retroperitoneum or other site consisting entirely of mature teratoma detected on serial abdominal/pelvic imaging during chemotherapy, and a significant decrease in or normalization of tumor markers.
Results: Precise serial abdominal/pelvic radiological measurements of the retroperitoneal masses were available for 7 of 9 patients. The median growth rate of growing teratoma syndrome measured as the increase in diameter during chemotherapy was 0.7 cm per month. The median growth rate measured as the increase in tumor volume was 12.9 cc per month. Median time from the start of chemotherapy to retroperitoneal lymph node dissection was 5.4 months (range 2.7 to 21.6). Pathological evaluation of the retroperitoneal lymph node dissection specimen revealed teratoma with no viable tumor in all 9 cases. There were 2 intraoperative complications (1 aortic and 1 ureteral injury) and 4 postoperative complications (2 ileus, 1 acute pancreatitis and 1 chylous ascites). At a median followup of 2 years 7 patients were alive without disease, 1 died of postoperative sepsis and 1 died of an unknown cause.
Conclusions: The growth rate of growing teratoma syndrome can vary significantly, which must be taken into account when evaluating cases. Retroperitoneal lymph node dissection is an effective treatment for growing teratoma syndrome, providing excellent local control and a low risk of progression.