Review articleGanglioglioma of brain stem and cervicomedullary junction: A 50Â years review of literature

•Through our historical review, we identified 142 brain stem ganglioglioma (GG) patients across 46 studies.•The average age was 11.4 years with significant difference b/w males and females under the age of 20 (p = 0.001).•Out of these patients, the medulla and pons was the most favorable location followed by medulla alone, and the CMJ.•In all tumors “gross total resection” (GTR, 16%), “subtotal resection” (STR, 48%) or “partial resection” (PR, 36%) was achieved.•Most subtypes II and III were partially resected (86% and 66%), while, subtype I underwent STR (66%).

Gangliogliomas are rare low-grade brain tumors composed of both neoplastic glial and neuronal cell elements. The treatment modalities are relatively different in this location and hence factors affecting outcome are poorly understood. We identified 142 brain stem GG patients across 46 studies. The average age was 11.4 years with significant difference b/w males and females under the age of 20 (p = 0.001). 100% of tumors in the CMJ while, 72% of type I and 86% of type II tumors demonstrated contrast enhancement. 72% of type I and 86% of type II tumors demonstrated contrast enhancement. All BRAF mutation positive tumors demonstrated contrast enhancement. Medulla and pons was the most favorable location followed by medulla alone, and the CMJ. In all tumors “gross total resection” (GTR, 16%), “subtotal resection” (STR, 48%) or “partial resection” (PR, 36%) was achieved. Most subtypes II and III were partially resected (86% and 66%), while, subtype I underwent STR (66%). Only 55% of the patients were positive for the BRAF V600E mutation. The overall survival dropped from 50% at 24 to 10% at 60 months, postoperatively. Through this review, we found that an early diagnosis, location, and with the imaging characteristics are vital part of the preoperative planning. Surgical resection is highly dependent on location in the brain stem with radical resection only limited to the most contrast enhancing portion of these tumors. BRAF V600E mutation status should be considered to allow the possibility of targeted therapy in case of a residual tumor and/or regrowth.