Astrocytomas IDH-mutant of posterior cranial fossa, clinical presentation, imaging features and onco-functional balance in surgical management.

Abstract

IDH-mutant astrocytomas (AIDHmut) in the posterior cranial fossa (PCF) are rare and present substantial diagnostic and therapeutic challenges due to their location. We analyzed patients with PCF AIDHmut from our institutions, treated between December 2021 and September 2024. Additionally, we conducted a systematic literature review (from January 2021 to September 2024) using PubMed, Ovid MEDLINE, and Ovid EMBASE to identify cases of PCF AIDHmut. We identified a total of 19 cases, including one institutional case. Most patients were young adults, with a male predominance (15 males, 4 females). Tumors primarily originated from the brainstem (94.7%), with only one case involving the cerebellum. Clinical presentations frequently included cranial nerve deficits, with diplopia being the most common symptom (47.4%). Adjuvant radiotherapy (IMRT, DT 54 Gy/27 fractions, 78.9%) and chemotherapy (temozolomide, 68.4%) formed the mainstays of treatment. Tumor grading revealed 63.2% (12/19) were WHO grade 2, 21% (4/19) were WHO grade 3, and 15.8% (3/19) were grade 4. The mean follow-up period was 45 months. PCF AIDHmut are rare but pose significant treatment challenges due to their location and infiltrative nature. Multimodal treatment-comprising surgery, radiotherapy, and chemotherapy-is essential for achieving long-term disease control. Subtotal resection followed by adjuvant therapies provides a favorable balance between tumor control and functional preservation.