P14.36 Characterising Meningiomas in young patients under 40

Abstract

Abstract BACKGROUND Meningiomas are the most common primary CNS tumor in adults, with a median age at diagnosis of 65 years and a female to male ratio of 2–3:1 (except in grade II, III meningiomas). Younger patients usually have a genetic background or history of prior radiation exposure. Based on population-level studies, approximately 80–85% of meningiomas are WHO grade I (benign), 15–18% grade II (atypical), and 1–3% grade III (anaplastic). This case series describes a single center experience of the presentation and pathology of meningiomas in patients under the age of 40. MATERIALS AND METHODS We reviewed the Sheba Medical Center Neurosurgery and radiotherapy databases containing patients who were operated on for meningioma between the years 2011–2020. Patients under 40 were selected and information from digital medical records was gathered on these patients, including pathology reports, surgical reports, clinical and radiological data, and the use of radiotherapy or medical treatments. RESULTS Of 600 patients in the database, 49 patients under 40 (8.3%) were identified and 54 tumors were reviewed (five patients were operated on for multiple meningiomas). 31 patients were female (63%); 2 were under 20 years old, 15 were age 20–29 and 32 were age 30–39 at first presentation. Seven patients had received prior radiation therapy for a childhood malignancy. 28 meningiomas were histology confirmed grade I (52%), 22 were grade II (41%), 2 were grade III (4%), and 2 (4%) were grade undetermined. 22 tumors were located in the skull base (41%) and 32 (59%) in the brain convexity. Of the skull base tumors, 16 were grade I, 5 were grade II, and one was grade III. Of the convexity tumors, 12 were grade I, 16 were grade II, and 2 were grade III. Median follow-up was 35 months, and longest follow-up time was 98 months. Six patients were treated with additional radiotherapy after surgery. CONCLUSION Our experience with meningioma patients under 40 revealed a different grade segregation than the older population, with younger patients showing a higher incidence of grade II tumors. These tumors are generally more aggressive, and require careful resection and consideration for post-surgical radiotherapy. Further validation with population based databases is required.