Associations of surgical menopause and hormone replacement therapy with meningioma development.

PURPOSE: Bilateral salpingo-oophorectomy (BSO) and hormone replacement therapy (HRT) exert opposing effects on systemic sex hormone exposure. Although HRT is frequently prescribed following BSO to mitigate surgical menopause, their combined impact on meningioma risk remains unclear. We evaluated meningioma incidence following BSO, HRT, or both. METHODS: Using the TriNetX database, we identified female patients for the following three categories: BSO only, HRT only, or BSO with subsequent HRT (BSO + HRT). Propensity score matching adjusted for demographics and meningioma risk factors. Outcomes included incident meningioma, cranial and spinal subtypes, time-to-event analyses, and surgical resection rates. RESULTS: Compared with controls, patients who underwent BSO demonstrated a significantly lower lifetime risk of cranial meningioma (RR:0.85, 95%CI:0.74–0.98, p = 0.026). Patients with HRT exposure demonstrated a significantly increased lifetime risk of meningioma diagnosis (RR:1.16, 95%CI:1.09–1.22, p < 0.0001). In contrast, patients who underwent BSO + HRT demonstrated a significantly elevated 10-year hazard (HR:1.684, 95%CI:1.40–2.02, p < 0.0001) and lifetime risk (RR:1.59, 95%CI:1.33–1.90, p < 0.001) of meningioma diagnosis. Risk was highest among BSO + HRT patients with hormonally-driven indications, including uterine fibroids, endometriosis, and gynecologic malignancy (RRs > 2, p < 0.001). Among patients who developed meningiomas, those with prior BSO + HRT were significantly less likely to undergo surgical resection (RR:0.41, 95%CI:0.23–0.73, p = 0.019) compared with controls. CONCLUSION: BSO + HRT patients have an increased risk of meningioma diagnosis. Risks were particularly elevated among women undergoing BSO for hormonally-driven indications. However, there is a lower likelihood of surgical resection among affected patients. These findings have implications for risk stratification, surveillance, and postoperative hormone management.