The malignant potential of teratomas in infancy and childhood: the MAKEI experiences in non-testicular teratoma and implications for a new protocol.

UNLABELLED:Since 1982, mature and immature teratomas have been recruited into the MAHO and MAKEI protocols of the German Society for Pediatric Oncology and Hematology (GPOH) for testicular and non-testicular germ cell tumors in order to study the epidemiology and clinical behaviour of teratomas. Patients were registered in the epidemiologic German Childrens Cancer Registry and the GPOH Childrens Tumor Registry for pathological review. Patients with immaturity grade 2 and 3 according to Gonzales-Crussi were eligible for adjuvant chemotherapy. The consecutive protocols MAKEI 83/86/89 have been published previously in detail (Klin Paediatr 1997; 209: 228-234, Med Pediat Oncol 1998; 31: 8-15) and will be compared to the data of MAKEI 96. For this comparison, 274 patients from MAKEI 83/86/89 and 261 patients from MAKEI 96 are evaluable. RESULTS:1) EFS after complete tumor resection has been estimated to 0.96 +/- 0.01 in both observation periods. 2) Incomplete tumor resection remains the main risk factor for relapse (EFS 0.55 +/- 0.09). 3) The relapse rate declined from 13.9 % in MAKEI 83/86/89 to 9.5 % in MAKEI 96. 4) In MAKEI 83/86/89 four newborns with teratoma died due to perioperative complications and nine children as a result of tumor progression, whereas in MAKEI 96 no newborn died, only one child died from tumor progression, and another child died during long time observation for another reason (meningitis). 5) In accordance to the experience of the MAKEI 83/86/89 studies, no child of the MAKEI 96 study presented with yolk sac tumor at recurrence if adjuvant chemotherapy was administered during first-line treatment because of immaturity. In contrast, more than half of the children with tumor recurrence after watch and wait strategy had yolk sac tumor in addition to teratoma.