The role of reoperation in paediatric cerebellar pilocytic astrocytoma

Abstract

Introduction Cerebellar pilocytic astrocytomas (cPAs) in childhood have long been recognized to have a good prognosis after total resection but the final outcome after incomplete surgery remains largely unpredictable with the incidence of symptomatic progressive disease ranging from 18-100%. Traditionally thought that GTR was required for long-term survival, small residuals were classically resected in a subsequent operation. Results Using our Pediatric Low-Grade Glioma (PLGG) database, 283 patients were identified to have a histopathological diagnosis of intracranial pilocytic astrocytoma between 1985-2020 of which 202 were within the cerebellum (68.2%). The majority of patients with cerebellar PA were between 1-10 years of age (n=147, 72.8%) without gender predominance (M:F=101:101), usually presenting with 1 lesion (n=195, 96.5%) and rarely with disseminated disease at diagnosis (N=7, 3.4%). The majority of initial surgeries for cerebellar PA achieved GTR (n=149, 73.8%). In patients with NTR or STR, the mean largest diameter of the post-operative residual was 1.1cm (0.2-3.7cm). Sixty-eight patients experienced relapse of their disease, 4 in which progression was multifocal. In 31 patients the neuro-oncology MDT recommended a second surgical resection at a mean time interval of 22.9 months (0.13-81.6 months) from the initial surgery. The children in the multiple operation cohort experienced more complications of therapy including ongoing endocrinopathy, treatment-associated hearing deficit, and neurocognitive deficiencies. Conclusion Residual disease in cPA should be maintained under clinocoradiological surveillance post-operatively with a more conservative approach when residual disease is not significantly changing over time.