gms | German Medical Science

Objective: Intracranial germ-cell tumors (GCTs) with a component of choriocarcinoma, yolk sac tumor or embryonal carcinoma, either in pure or mixed form, are classified as nongerminomatous germ-cell tumors (NGGCTs). These tumors comprise 40-50% of all intracranial GCTs and differ from pure germinomas with respect to prognosis and oncological treatment. The role of surgery in these tumors regarding the need for histological confirmation, as well as the role and timing of resective surgery are controversial. Based on the data of the European SIOP CNS GCT 96 trial we analyzed the impact of primary surgery and of delayed resection of residual tumor after chemotherapy on outcome.

Method: Until May 2012, 200 patients with NGGCT were treated according to the SIOP CNS GCT 96 protocol: Diagnosis by marker elevation (AFP, Beta-HCG) or histology, four cycles of chemotherapy, reevaluation regarding resection of residual tumor, followed by radiotherapy. Median age was 12 years (range 0-30yrs), 150 were boys. Primary tumor site was pineal (n=107) and sellar-suprasellar (n=51), bifocal (n=20), and other (n=22). We analyzed the impact of resective surgery in relationship to the tumor site, pineal vs sellar-suprasellar.

Results: 5-yr- progression-free survival for the whole cohort of 200 patients was 69±4%. In pineal tumors 54/107 had histology at diagnosis with either upfront resection (36/54) or biopsy (18/54). 53/107 had diagnosis by markers only. Of 20 patients with an upfront gross-total resection 7 had an event. Second-look surgery was performed in 29 patients, 4 of these 29 patients had an event. An event occurred in 28/46 patients with residual tumor after chemotherapy who did not undergo second-look surgery prior to radiotherapy. In sellar-suprasellar tumors 26/51 had histology at diagnosis with 21/26 resective and 5/26 biopsy procedures. Marker-only diagnosis was done in 25/51 patients. Of 4 patients with primary gross-total resection 1 had an event. Second-look surgery was done in 7 patients, 2/7 had an event. An event occurred in 6/31 patients with residual tumor who did not undergo second-look surgery.

Conclusions: Diagnosis by markers alone is feasible. There was no benefit of primary resection. While second-look surgery seems to improve outcome in NGGCT primarily located in the pineal region, the impact of this strategy is less clear in sellar-suprasellar tumors and an attempt at second-look gross total resection needs to be weighted against potentially harmful side-effects.