Is there a role for high dose chemotherapy with hematopoietic stem cell rescue in patients with relapsed supratentorial PNET?

Supratentorial primitive neuroectodermal tumors (sPNET) are rare childhood brain tumors. There is no standard strategy for treating relapsed sPNETs. The role of high dose chemotherapy with hematopoietic stem cell rescue (HDC with HSCR) in treating relapsed sPNET is controversial. A systematic review of the literature regarding outcome of patients with relapsed sPNET treated with HDC and HSCR was performed to examine the potential predictive factors that would justify its use in this subset of patients. Forty-six patients were identified fulfilling the inclusion criteria. Of those, 15 patients were infants and 15 were pineoblastomas. With a median follow-up of 40 months (range 3-123 months) 15 patients were reported alive. Thirteen patients out of the 15 survivors did not receive craniospinal irradiation (CSRT). The 12 month overall survival (OS) of the cohort was 44.2 ± 7.5 months. Twelve-month OS for children less than 36 months was 66.7 ± 12.2 months while for older children it was 27.8 ± 10.6 (P = 0.003). Twelve-month OS was 20.0 ± 10.3 for those patients with pineoblastoma versus 54.6 ± 9.0 for those with non-pineal sPNETs (P < 0.001). Cox regression analysis revealed pineal location as the only independent adverse prognostic factor. In conclusion high dose chemotherapy with HSCR might lead to survival primarily in younger children with relapsed sPNET even in the absence of concomitant use of radiotherapy, whereas the outcome in older children and/or in pineal location is extremely poor with this modality.