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.

中文翻译：

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P14.36 40 岁以下年轻患者脑膜瘤的特征

背景脑膜瘤是成人中最常见的原发性 CNS 肿瘤，诊断时的中位年龄为 65 岁，女性与男性的比例为 2-3:1（II、III 级脑膜瘤除外）。年轻患者通常有遗传背景或既往辐射暴露史。根据人群水平的研究，大约 80-85% 的脑膜瘤为 WHO I 级（良性）、15-18% 的 II 级（非典型）和 1-3% 的 III 级（间变性）。本案例系列描述了 40 岁以下患者脑膜瘤的表现和病理学的单一中心经验。 材料和方法 我们审查了 Sheba 医学中心神经外科和放射治疗数据库，其中包含 2011-2020 年期间因脑膜瘤接受手术的患者. 选择了 40 岁以下的患者，并从这些患者的数字医疗记录中收集信息，包括病理报告、手术报告、临床和放射学数据以及放射治疗或药物治疗的使用情况。结果 数据库中的 600 名患者中，40 岁以下的 49 名患者（8.3%）被确定，54 名肿瘤被审查（5 名患者因多发性脑膜瘤接受手术）。31 名患者为女性（63%）；2 人在 20 岁以下，15 人在 20-29 岁之间，32 人在首次就诊时年龄在 30-39 岁之间。七名患者曾因儿童恶性肿瘤接受过放射治疗。28 例脑膜瘤经组织学证实为 I 级（52%），22 例为 II 级（41%），2 例为 III 级（4%），2 例（4%）为未定级。22 个肿瘤位于颅底（41%），32 个（59%）位于脑凸面。在颅底肿瘤中，I级16个，II级5个，III级1个。在凸面肿瘤中，I级12个，II级16个，III级2个。中位随访时间为35个月，最长随访时间为98个月。六名患者在手术后接受了额外的放射治疗。结论 我们对 40 岁以下脑膜瘤患者的经验显示出与老年人群不同的分级隔离，年轻患者的 II 级肿瘤发病率较高。这些肿瘤通常更具侵袭性，需要仔细切除并考虑进行术后放疗。需要对基于人口的数据库进行进一步验证。最长随访时间为98个月。六名患者在手术后接受了额外的放射治疗。结论 我们对 40 岁以下脑膜瘤患者的经验显示出与老年人群不同的分级隔离，年轻患者的 II 级肿瘤发病率较高。这些肿瘤通常更具侵袭性，需要仔细切除并考虑进行术后放疗。需要对基于人口的数据库进行进一步验证。最长随访时间为98个月。六名患者在手术后接受了额外的放射治疗。结论 我们对 40 岁以下脑膜瘤患者的经验显示出与老年人群不同的分级隔离，年轻患者的 II 级肿瘤发病率较高。这些肿瘤通常更具侵袭性，需要仔细切除并考虑进行术后放疗。需要对基于人口的数据库进行进一步验证。并需要仔细切除并考虑进行术后放疗。需要对基于人口的数据库进行进一步验证。并需要仔细切除并考虑进行术后放疗。需要对基于人口的数据库进行进一步验证。