PATH-99. Single Health System Experience with Hormone Receptor Expression in Meningiomas

Abstract Hormone receptor expression for progesterone (PR), estrogen (ER), and androgen (AR) is not assessed routinely in meningioma cases. PR expression typically has an inverse relationship with tumor grade, but this finding is inconsistent. Less is known about ER and AR expression and the implications tumor behavior. Previous studies have associated ER expression with higher grade meningiomas, while AR expression was correlated with PR expression. A retrospective review of meningioma cases was conducted from August 2024 through February 2025 using the IU Health Pathology Laboratory database. Each case was assessed to ensure that immunohistochemistry (IHC) for PR, ER, and AR was performed. The reports were reviewed for patient demographics, tumor grade, tumor location, recurrence status, receptor expression, and molecular results. A total of 55 meningioma cases from 54 patients were identified. The mean patient age was 58 years (range: 22-81 years). Thirty-five (64.8%) patients were female, and 19 (35.2%) were male (female to male ratio of 1.8:1). Fifty-two (94.5%) cases were PR(+), 48 (87.3%) were AR(+), and 3 (5.5%) were ER(+). Thirty-five (63.6%) cases were Grade 1, 13 (23.6%) were Grade 2, and 4 (7.3%) were Grade 3. Many cases showed similar expression patterns for PR and AR. No clear trend of decreasing expression of PR or AR was seen with increasing tumor grade. Our initial data is similar to that observed in other studies with little to no expression of ER in meningiomas and comparable AR and PR expression. With routine assessment of these three hormone receptors, however, we can aid in determining if expression or lack thereof of ER and AR impacts behavior of these tumors and how they are treated. Further analyses are required to further understand these tumors, and additional cases will be added to our initial set of 55 cases. Other variables to be examined include but are not limited to MIB/Ki67, BSA/BMI, comorbidities, use of hormone replacement therapy, and overall survival.