# Primary Pediatric Brain Tumors in a Tertiary Referral Center in Iran: A 13-Year Retrospective Analysis

## TL;DR

This study analyzed brain tumor cases in Iranian children over 13 years, finding low-grade tumors were most common and surgeries increased over time.

## Contribution

The study provides a detailed histopathological analysis of pediatric brain tumors in Iran, highlighting regional and temporal trends.

## Key findings

- Pilocytic astrocytoma was the most common tumor type (20.9%), followed by medulloblastoma and ependymoma.
- Grade IV tumors were significantly more common in the infratentorial space (P<0.001).
- The number of surgeries increased significantly over time (incidence rate ratio: 1.127/year, P<0.001).

## Abstract

Pediatric central nervous system (CNS) tumors are among the most common childhood malignancies and a leading cause of cancer-related death. This study aimed to describe the histopathological spectrum of primary brain tumors in children over a 13-year period in a tertiary referral center in Iran.

In this existing data study (EDS), we reviewed the medical records of 549 patients aged 0–17 years who underwent surgical resection of brain tumors between 2008 and 2020. Tumor characteristics, including histology, location, and World Health Organization (WHO 2016) grade, along with patient age and sex, were extracted. Descriptive and comparative analyses were conducted. Temporal trends for single-center in the number of pediatric brain tumor surgeries performed in our center were assessed using Poisson regression.

The mean age at diagnosis was 5.1 years, with a male-to-female ratio of 1.3:1. Pilocytic astrocytoma (20.9%) was the most common tumor, followed by medulloblastoma (15.3%) and ependymoma (11.3%). Tumors were nearly evenly distributed between supratentorial (48.6%) and infratentorial (48.5%) regions. Grade I tumors were most frequent overall, while Grade IV tumors were significantly more common in the infratentorial space (P<0.001). No significant differences in tumor distribution were observed by sex or age group. The number of surgeries increased significantly over time (incidence rate ratio: 1.127/year, P<0.001), with no subgroup differences in temporal trend.

This single-center study provides institutional-level insights into the histopathological characteristics of pediatric brain tumors. The predominance of low-grade tumors observed emphasizes the need for national pediatric neuro-oncology registries, particularly in low- and middle-income countries, to enable more representative data collection and planning.