Skull Base Meningiomas: Is Surgical Resection Enough? Outcome Evaluation and Prognostic Factors Analysis in a Single-Center Cohort

Background Surgical resection represents the mainstay of treatment in skull base meningiomas (SBMs). Considering the high recurrence rate reported, an adjuvant radiation therapy (RT) treatment should be considered. The aim of this study was to evaluate the progression-free survival (PFS), overall survival (OS), and prognostic factors conditioning outcome. Methods Patients receiving surgical resection for grade I SBMs were included. The extent of resection (EOR) was dichotomized as gross total resection (GTR) and subtotal resection (STR). RT was administered only in patients receiving STR. Clinical outcome was evaluated by brain magnetic resonance imaging (MRI) performed every 6 months for the first year and yearly thereafter. Results From January 2000 to December 2015, 123 patients were treated. The majority were females (70.7%), with a Karnofsky Performance Score (KPS) ≥80 (95%), and symptoms at diagnosis (91%). GTR was performed in 30% of cases and STR in 70%. RT was performed in 18 (20.9%) patients at diagnosis and in 29 (33.7%) patients at progression. Improvement or stability of neurologic status was obtained in 78.9% of patients. The median follow-up time was 91 months (range: 40–230 months). Local recurrence occurred in 34 (27.6%) patients at a median time of 45 months (range: 6–214 months). The median, 2-, 5-, and 10-year PFS were 193 months, 89.3, 81.8, and 72.5%, respectively. On univariate and multivariate analyses, factors impacting on PFS were EOR, tumor location, neurologic postoperative status, and adjuvant RT in STR. Conclusions A safe surgical resection followed by RT adjuvant treatment could represent the better choice to obtain local control maintaining neurologic integrity. Our data underlined the value of adjuvant RT in incompletely resected meningiomas.

IgG4-related pachymeningitis masquerading as foramen magnum meningioma: illustrative case

BACKGROUND Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated inflammatory condition with potential multiorgan involvement. Common manifestations include autoimmune pancreatitis and retroperitoneal fibrosis. Pathological analysis reveals lymphoplasmacytic infiltrate rich in IgG4-positive cells and characteristic storiform fibrosis. Early treatment with glucocorticoids may prevent progression to poorly responsive fibrotic disease. OBSERVATIONS A 63-year-old female patient presented with reports of left-sided headaches, nausea, and photophobia in addition to recently diagnosed chronic rhinosinusitis (CRS). Neurological examination revealed dysarthria secondary to left hypoglossal nerve palsy. Computed tomography (CT) revealed a contrast-enhancing extraaxial mass at the left craniocervical junction, CRS with secondary hyperostotic reaction, and multiple hypodense lesions involving the occipital bone. Magnetic resonance imaging revealed a dural-based lesion involving the foramen magnum and invading the left hypoglossal canal. The patient underwent a far-lateral craniotomy. Histopathological analysis revealed severe lymphoplasmacytic inflammation, storiform fibrosis and rich plasma-cell population positive for IgG4. Serum IgG4 was markedly elevated. Total-body CT showed no systemic involvement. The patient was diagnosed with IgG4-RD and was prescribed prednisone, with normalization of her IgG4 levels after 1 month. LESSONS IgG4-RD may mimic a variety of diseases, including skull-base meningiomas and CRS. Accurate diagnosis and expedited administration of steroids may prevent unnecessary interventions and progression to treatment-resistant fibrosis.

High prevalence of anterior pituitary deficiencies after cranial radiation therapy for skull base meningiomas

Background Cranial irradiation represents one of the first line treatment proposed in skull base meningiomas. While cranial irradiation is associated with a high risk of secondary hypopituitarism, few studies focused on the specific location of skull base meningiomas. Methods Fifty-two adults receiving photon-beam therapy for skull base meningiomas between 2003 and 2014 in our Institution were included. Anterior pituitary (ACTH, FSH, GH, LH, TSH and prolactin) as well as corresponding peripheral hormones (8 am-Cortisol, IGF-1, fT3, fT4, 17βestradiol or testosterone) were biologically screened before radiotherapy (baseline), then yearly until March 2019. The pituitary gland (PG) was delineated on CT and the mean dose delivered to it was calculated. Results Mean age at diagnosis was 56 +/− 14 years. Median follow-up was 7 years. Up to 60% of patients developed at least ≥2 pituitary deficiencies, 10 years after radiotherapy. Gonadotroph, thyrotroph, corticotroph and somatotroph deficiencies occurred in 37, 28, 18 and 15% of patients, respectively. Hyperprolactinemia was found in 13% of patients. None patient had only one pituitary deficiency. In the multivariate analysis, a delivered dose to the PG ≥ 50 Gy or a meningioma size ≥40 mm significantly increased the risk of developing hypopituitarism. Conclusions Over a long-term follow-up, cranial radiation therapy used in skull base meningiomas led to a high prevalence of hypopituitarism, further pronounced in case of tumor ≥4 cm. These results advocate for an annual and prolonged follow-up of the pituitary functions in patients with irradiated skull base meningiomas.

Skull base meningiomas: development of treatment methods

The review describes the treatment methods for skull base meningiomas and promising modern trends in this area. The most significant events in the development of meningiomas’ surgical treatment are described. The current research and scientific approaches to the skull base meningiomas’ treatment are presented: medical robotic systems, targeted therapy, radiosurgery, and proton therapy.