Two-decade clinicopathological spectrum of gliomas at a tertiary center in LMIC: histological profile and the molecular diagnostic gap.

Introduction: Diffuse gliomas are the most common malignant primary central nervous system (CNS) tumors, and contemporary World Health Organization (WHO) criteria require molecular markers, mainly isocitrate dehydrogenase (IDH) status and 1p/19q codeletion, for an integrated diagnosis. Access to these tests remains uneven in low- and middle-income settings. Data describing the glioma spectrum and the practical impact of limited molecular testing in Jordan are scarce. Method: We retrospectively retrieved all glioma-related surgical pathology specimens accessioned between 2003 and 2024 at a tertiary academic center in Jordan through a structured text search. Histological category, WHO grade, anatomic site, immunohistochemical (IHC) profile, Ki-67 index, and documented IDH/1p-19q status were extracted from the free-text reports. After exclusion of non-neoplastic, non-glial, and unclassifiable records, 430 specimens from 332 patients formed the analytic cohort. Ki-67 across grades was compared with the Kruskal-Wallis test and categorical age associations with the chi-square test. Results: The median age was 48 years (IQR 28-63; range 3-98) with a male predominance (male-to-female ratio 1.30). Glioblastoma was the most frequent diagnosis (174/430; 40.5%), followed by non-pilocytic astrocytoma (17.9%) and unspecified diffuse glioma (12.8%). The Ki-67 index increased significantly across WHO grades (median 3%, 2%, 20%, and 30% for grades I-IV; Kruskal-Wallis p < 0.0001). An actual IDH result was documented for only 10 specimens (2.3% overall; 3.0% of 329 diffuse gliomas), while reports explicitly noted that testing was indicated but unavailable in a further 17.4%. Glioblastoma was almost exclusive to adults and pilocytic astrocytoma to children (both p < 0.0001). Annual case volume rose from approximately 15 to 25 specimens per year, yet documented IDH results appeared only after 2017 and in fewer than 5% of recent specimens. Conclusion: Over two decades, gliomas at our center were diagnosed predominantly on morphology and a limited IHC panel. The near-absence of molecular results means the large majority of diffuse gliomas cannot be fully classified by current WHO standards, a concrete diagnostic-capacity gap with direct implications for prognostication, treatment stratification, and trial eligibility. The findings support investment in accessible molecular neuropathology, including surrogate IHC and regional referral testing.