Treatment for posterior fossa dissemination of primary supratentorial glioma

Object. This study was designed to assess the presentation, management, and outcome of cases involving patients who had a supratentorial glioma that subsequently progressed in the posterior fossa (PF). Methods. The authors performed a retrospective chart review of adult patients treated between 1997 and 2005 for supratentorial gliomas that progressed in the PF. The 29 patients with PF progression in this study were relatively young (median age of 34 years at original presentation). Twenty of these patients presented with symptoms. The symptoms were typically nonspecific to this population, at times leading to delays in diagnosis. Overall, these symptoms resolved in eight patients (40%) and progressed or remained unchanged in 12 (60%). Patients treated with more than 5000 cGy of radiation administered to the PF were more likely to have symptom resolution than those who received any other form of treatment, including reduced doses of radiation (p = 0.004). The patients treated with higher doses also survived significantly longer after PF progression (univariate analysis, p = 0.01, and after adjusting for tumor grade, p = 0.04). Conclusions. Patients with PF progression of supratentorial infiltrative gliomas may benefit from treatment, and the authors recommend more than 5000 cGy of radiation to the PF if prior radiotherapy ports and doses allow.