Neurofibromatosis type 1 (NF1) is an autosomal dominant tumor predisposition syndrome that affects children and adults. Individuals with NF1 are at high risk for central nervous system neoplasms including gliomas. The purpose of this review is to discuss the spectrum of intracranial gliomas arising in individuals with NF1 with a focus on recent preclinical and clinical data. In this review, possible mechanisms of gliomagenesis are discussed, including the contribution of different signaling pathways and tumor microenvironment. Furthermore, we discuss the recent notable advances in the developing therapeutic landscape for NF1-associated gliomas including clinical trials and collaborative efforts.

PURPOSE: High-dose methotrexate (HD-MTX) is the backbone of curative therapy for CNS lymphoma. Because of toxicity, MTX is administered in the inpatient setting along with hyperhydration and monitoring until MTX clearance is documented (3-5 days). Frequent hospitalizations result in patient time away from work, home, and exposure to potential iatrogenic/nosocomial complications. Here, we aim to demonstrate feasibility of HD-MTX administration in the outpatient setting with low-dose glucarpidase facilitating clearance. METHODS: This is a prospective nonrandomized study of outpatient HD-MTX followed by glucarpidase 2000u (ClinicalTrials.gov identifier: NCT03684980 ). Eligible patients had CNS lymphoma, creatinine <1.3 mg/dL, and previously tolerated HD-MTX. Patients were enrolled between May 2020 December 2021 for one HD-MTX treatment. Patients could re-enroll for subsequent doses of HD-MTX as eligibility and slots permitted. MTX 3.5 g/m ² was administered once over 2 hours, preceded by standard hydration and followed by an additional 2 hours of dextrose 5% in water with NaHCO ₃ 75 mEq at 150 cc/h. Glucarpidase 2000u was administered once in the clinic 24 hours later. The primary end point was MTX level 48 hours after HD-MTX. RESULTS: Twenty doses of outpatient HD-MTX with glucarpidase were administered to seven patients. After 20 of 20 (100%) treatments, serum MTX levels were reduced to <100 nmol/L. Treatments were well-tolerated, and no admissions were required. One patient received additional outpatient hydration for elevated creatinine. Development of antiglucarpidase antibody was rare and did not affect treatment. CONCLUSION: Outpatient HD-MTX with glucarpidase is safe and well-tolerated and has the potential to alter standard treatment for CNS lymphoma.

Leptomeningeal metastasis is extremely rare in patients with ovarian cancer, but should be considered in patients presenting with neurologic deficits such as cauda equine syndrome. Given its poor prognosis and lack of data currently on management, additional studies are needed to optimize treatment regimens and improve outcomes.

Although neurofibromatosis (NF) was initially recognized in the nineteenth century, only in the past two decades we have witnessed a paradigm shift in therapeutics. This progress is driven by the increasing understanding of the natural history of the NF-associated tumors and understanding of the molecular landscape of these disorders. Multiple clinical trials have been launched evaluating non-surgical treatment modalities and more studies are in the pipeline. Recently, the NF community has adopted standardized endpoints recommended by the Response Evaluation in Neurofibromatosis and Schwannomatosis (REiNS) International Collaboration established in 2011. Such collaborations among academic, regulatory and supporting communities are crucial for providing the infrastructure needed for advancing the therapeutic development in the field of NF.

Background: Brain tumors can present as focal neurologic deficits (reflecting the tumor location) or generalized symptoms due to increased intracranial pressure. Occasionally, brain tumors can be found incidentally in asymptomatic patients or in patients with unrelated symptoms who undergo brain imaging. The term incidentaloma is used to refer to these imaging abnormalities. Objective: The object of this study was to examine the prevalence and correlates of asymptomatic glioma in a large epidemiological study of brain tumors. Methods: The analysis was based on a large series of patients with glioma (N = 1989) enrolled in a multicenter clinic-based epidemiologic study between 2005 and 2017. Patients were considered asymptomatic from the tumor, and thus as having an incidentally detected glioma (IDG), if the tumor was diagnosed during workup of injury or unrelated medical condition. Results: A total of 32 of 1989 (1.6%) patients were asymptomatic at diagnosis. The leading indication for brain imaging in IDG was non-workplace injuries followed by medical workup for unrelated conditions. IDG was more prevalent in patients younger than 50 years of age (2.6% vs 1.0%). IDG was also more common in patients with low grade gliomas (4.7% for WHO grade II and 1.5% for WHO grade III) vs glioblastomas (0.6% in WHO grade IV). Conclusion: The present data suggest that gliomas may be found incidentally, especially among low grade gliomas. Studies of IDG may be useful as a proxy for early detection of tumor as a means to improve patient survival.