Epidemiology of Primary Intracranial Neoplasms: A Single-Institute Cross-Sectional Study in Iran

Primary central nervous system (CNS) tumors represent a diverse group of neoplasms with variable histologic features and clinical behavior. In Iran, the lack of a robust cancer registry has limited comprehensive epidemiological evaluations. This study aimed to assess the distribution, histopathological subtypes, and demographic characteristics of primary intracranial tumors diagnosed at a major referral center in Tehran.

This retrospective cross-sectional study reviewed 1603 histologically confirmed primary CNS tumor cases diagnosed at Loghman-e-Hakim Hospital in Tehran, Iran, from 2010 to 2017. Demographic data, tumor location, histopathologic classification, and the World Health Organization (WHO) grade were extracted from pathology reports. Tumors were classified based on the 2007 and 2016 WHO CNS tumor classifications. Statistical analysis was performed using SPSS Version 23, employing chi-square and t tests with a significance level set at P < 0.05.

The mean age of patients was 42.9 ± 17.4 years, with a slight female predominance (52.5%). The most common tumor groups were gliomas (38%) and meningiomas (37.9%). Glioblastoma (14.6%) and transitional meningioma (14.2%) were the most prevalent subtypes. Meningiomas were significantly more frequent in females (odds ratio, 3.14; 95% CI, 2.54-3.89; P < 0.001), while gliomas and embryonal tumors were more common in males. The age distribution showed that gliomas peaked in the 20-40-year-old group, whereas meningiomas were most frequent in patients aged 41-60 years. A statistically significant variation in tumor distribution by age was observed for several tumor types. An increasing trend in CNS tumor diagnoses was noted over the study period, especially for gliomas and meningiomas.

This study provides a comprehensive overview of the epidemiological and histopathological profile of CNS tumors in a single-center Iranian cohort. The findings are consistent with global trends, particularly in the sex- and age-specific distributions of gliomas and meningiomas. The increasing incidence observed underscores the need for enhanced surveillance and a national cancer registry to improve data accuracy and healthcare planning.