Intracranial venous malformation masquerading as a meningioma in PI3KCA-related overgrowth spectrum disorder

Genetic Profile of Arteriovenous Anomalies of the Head and Neck: Implications in Progression and Therapeutic Approaches

BACKGROUND

Arteriovenous Malformations (AVMs) are complex vascular anomalies that are usually sporadic and can have a variable clinical course. Treatment of AVMs can lead to severe sequeale and require thorough decision-making. There is a lack of standardized treatment protocols showing a growing need for pharmacological targeted therapies, specially in the most severe cases where surgery may not be feasible. Current knowledge in molecular pathways and genetic diagnosis have shed light in the pathophysiology of AVMs, opening possibilities for personalized treatment strategies.

METHODS

We performed a retrospective review of patients with head and neck AVMs treated in our department between 2003 and 2021 and performed a complete physical examination and imaging with ultrasound and angio-CT or MRI. Patients underwent genetic testing on AVMs' tissue samples and/or peripheral blood samples. Patients were grouped according to the genetic variant and a correlation between phenotype and genotype was studied.

RESULTS

22 patients with head and neck AVMs were included. We found eight patients with varians in MAP2K1, four patients with pathogenic variants in KRAS, six patients with pathogenic variants in RASA1, one patient with a pathogenic variant in BRAF, one patient with a pathogenic variant in NF1, another patient with a pathogenic variant in CELSR1 and one patient with pathogenic variants in PIK3CA and GNA14. Patients with MAP2K1 variants were the biggest group, with a moderate clinical course. Patients with KRAS mutations showed the most aggressive clinical course and a high rate of recurrence and osteolysis. Patients with RASA1 variants showed a characteristic phenotype with an ipsilateral capillary malformation in the neck.

CONCLUSION

We found a correlation between genotype and phenotype in this group of patients. The genetic diagnosis of AVMs is recommended in order to stablish a personalized treatment strategy. Targeted therapies are currently being investigated with promising results and may be recommended in addition to conventional surgical or embolization procedures, specially in the most complex cases.

LEVEL OF EVIDENCE

Level IV.

Review of meningioma diagnosis and management

Meningiomas are the most common intracranial tumors in adult patients. Although the majority of meningiomas are diagnosed as benign, approximately 20% of cases are high-grade tumors that require significant clinical treatment. The gold standard for grading central nervous system tumors comes from the World Health Organization Classification of Tumors of the central nervous system. Treatment options also depend on the location, imaging, and histopathological features of the tumor. This review will cover diagnostic strategies for meningiomas, including 2021 updates to the World Health Organization's grading of meningiomas. Meningioma treatment plans are variable and highly dependent on tumor grading. This review will also update the reader on developments in the treatment of meningiomas, including surgery, radiation therapy and monoclonal antibody treatment.

Embryonal and non-meningothelial mesenchymal tumors of the central nervous system - Advances in diagnosis and prognostication

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