Clinicoradiological Features, Surgical Management, and Prognostic Factors in Expansive Brainstem Lesions: A 16-Year Comparative Analysis of Intrinsic versus Infiltrating Pathologies at a Tertiary Referral Center.

Abstract

Expansive brainstem lesions (BSLs) present significant diagnostic and management challenges. This study evaluates the clinical landscape and prognostic factors of BSLs. To report our institutional experience with expansive brainstem lesions in Tunisia, describing their epidemiological, clinical, radiological, therapeutic, and prognostic features, with a comparative analysis of intrinsic versus infiltrating lesions. Retrospective study of 48 patients treated over 16 years (2000-2015). Univariate associations were tested using Chi-square, Fisher's exact, and t-tests. Survival was estimated via Kaplan-Meier. Due to the small sample size, multivariable modeling was not feasible. The cohort (mean age 25 years) showed a 1:1 sex ratio. Common pathologies: gliomas (38%), medulloblastomas (19%), and cavernomas (13%). Complete resection (n=15) was associated with lower recurrence rates (56%) than incomplete resection (71%, p=0.37) or no surgery (75%, p=0.42), though not statistically significant. Postoperative complications occurred in 75%, including meningitis (30%) and cranial neuropathies. Overall mortality was 54%. On univariate analysis, a consultation delay of less than six months (75% mortality vs. 20% for >6 months, p=0.003) and presence of pyramidal syndrome (62% mortality vs. 25%, p=0.021) were associated with higher mortality. Crucially, shorter consultation delay is interpreted as a surrogate marker of aggressive tumor biology rather than a modifiable patient factor. In our local experience, managing BSLs remains high-risk. While total resection may improve local control, the risk-benefit ratio for high-grade or infiltrating tumors requires careful individualization, including consideration of a primarily diagnostic or palliative role. Our findings may not be generalizable.