Abstract
BACKGROUND: Meningiomas are the most common primary central nervous system neoplasms originating from the arachnoid cap cells and constitute between 13% and 26% of all intracranial tumors. AIMS AND OBJECTIVES: The aim of the study was to analyze the age-, sex-, and site-wise distribution of different histological patterns of meningiomas seen in our center and to assess the status of estrogen receptor (ER), progesterone receptor (PR), and proliferation marker Ki-67 in various grades of meningioma. MATERIALS AND METHODS: A prospective study was done in 90 cases. Patients presented with symptoms of headache and seizure and underwent subsequent excision surgery at Neurosurgery Department were taken. We have studied histological typing and grading of the tumors, and immunohistochemical staining was done for ER, PR, and Ki-67. STATISTICAL ANALYSIS: Two-group comparison was done using Mann-Whitney U-test and Fisher's exact test. Comparison of Ki-67 expression between Grade 1 and Grade 2 meningiomas was determined using Mann-Whitney U-test. Comparison of ER and PR status between different histological grades was done by Fisher's exact test. Two-tailed P < 0.001 was considered statistically significant. RESULTS: According to histological type, meningothelial meningioma is most common (38.8%) followed by transitional (22.2%). PR positivity is seen in 96.34% of Grade 1 tumors, and all Grade 2 tumors were PR negative (Fisher's exact test P < 0.001). About 3.66% of Grade 1 and all Grade 2 tumors were positive for ER (Fisher's exact test two-tailed P < 0.001). Mean Ki-67 labeling index (LI) was 2.57 ± 1.674 among Grade I tumors, 7.11 ± 1.084 in Grade II meningiomas. CONCLUSIONS: Most of Grade 1 meningiomas show PRs positivity and lack of ERs positivity. Meningiomas with higher proliferation index and negative PR are very likely to be Grade II or Grade III. Evaluation of ER, PR status, and Ki-67 labeling index (LI) with histological evaluation helps us in providing information about the biologic behavior of meningiomas.