Relapsing intracranial germ cell tumours warrant retreatment

Abstract Background The optimal therapeutic strategy for relapsing intracranial germ cell tumours (IGCTs) has not been clearly established. Methods Relapses of IGCTs, occurring from 01/01/1990 to 31/12/2014, were retrieved from the Societe Francaise d’Oncologie Pediatrique-TGM 90, 92 and GCT 96 protocols, and from the National Childhood Solid Tumour Registry. Refractory IGCTs were excluded. Results Forty-four relapsing IGCTs were identified: 14 were initially treated for histologically proven germinomas (germinoma group), 5 for non-histologically proven germinomas (putative germinoma group) and 25 for non-germinomatous germ cell tumours (NGGCTs) (NGGCT group). In the germinoma group, the 5-year event-free survival (EFS) and overall survival (OS) were 79% (95% confidence interval [CI]: 47–93) and 86% (95% CI: 54–96), respectively. Only one of the 11 patients treated with reirradiation experienced a further relapse. A trend of better EFS was observed for relapses at sites that were not initially involved: 5-year EFS of 100% versus 67% (95% CI: 28–88), p = 0.09. In the putative germinoma group, 4 of 5 patients experienced a further event, leading to 2 deaths. In the NGGCT group, the 5-year EFS and OS were 56% (95% CI: 35–73) and 60% (95% CI: 38–76), respectively. A significant improvement in outcomes after high-dose chemotherapy (HDC) was observed: 5-year OS of 72% (95% CI: 46–87) versus 29% (95% CI: 4–61), p = 0.006. Conclusion Relapsing germinomas are highly curable; reirradiation appears to play a key role. Histological proof at initial diagnosis if markers are negative is crucial. Despite inferior outcomes relapsing, NGGCTs can be cured in a significant proportion of cases provided intensive treatment including HDC is applied.