Venous malformations

Microwave ablation with hydrodissection used for the treatment of vascular malformations: effectiveness and safety study

Object

The aim of the study was to investigate the safety, effectiveness, and peripheral nerve protection in ultrasound-guided microwave ablation (US-guided-MWA) for vascular malformations (VMs) closely related to peripheral nerve.

Materials and methods

From August 2019 to February 2022, 31 patients with 39 VMs received US-guided-MWA. All lesions were confirmed to be closely related to the peripheral nerve by imaging evaluation. Hydrodissection was applied to protect surrounding normal tissue, including peripheral nerves. The patients were followed up at 1day, 2 days, 3 days, 1 week, 1 month, 3 months after operation. Measurements of lesion volume, volume reduction ratio (VRR), sensory and functional abnormalities of adjacent nerves, number of treatments, complication details, personal satisfaction, recurrence, and symptom improvement were recorded.

Results

Among the 39 VMs, the maximum volume is 128.58ml, while the minimum volume is 0.99ml. After a mean follow-up of 13.06 ± 4.83 months, the mean numerical rating scale (NRS) score decreased from 5.13 ± 1.65 to 0.53 ± 0.83 (P<0.0001). The mean mass volume was reduced from 18.34 ± 24.68 ml to 1.35 ± 2.09 ml (P=0.0001). The VRR of all lesions was 92.06%. However, the mean number of treatments was only 1.64 ± 0.87. All patients were satisfied with the technique, with a mean satisfaction score (SC) of 9.23 ± 1.13. There were no motor function abnormalities of the related nerves. 10 patients felt numbness in the ablation area after ablation, and gradually recovered after 1 month.

Conclusion

US-guided-MWA serves as a novel alternative approach for patients with VMs. Preoperative evaluation of the relationship between VMs and peripheral nerves combined with intraoperative hydrodissection is an effective and safe method to prevent nerve injury.

Sociodemographic characteristics of pediatric patients with vascular malformations: Results of a single site study

Vascular malformations, the abnormal development of blood vessels, are a rare set of congenital anomalies. The sociodemographic factors associated with vascular malformations in pediatric patients are poorly understood. This study examined sociodemographic factors of 352 patients presenting to a single vascular anomaly center from July 2019 to September 2022. Characteristics such as race, ethnicity, sex, age at presentation, degree of urbanization, and insurance status were recorded. This data was analyzed by comparing the different types of vascular malformations, including arteriovenous malformation, capillary malformation, venous malformation (VM), lymphatic malformation (LM), lymphedema, and overgrowth syndrome. Patients were primarily white, not Hispanic or Latino, female, had private health insurance, and were from the most urban setting. No differences in sociodemographic factors were found among the different vascular malformations except patients with VM presented at a later age than patients with LM or overgrowth syndrome. This study provides novel insight into the sociodemographic factors of pediatric patients presenting with vascular malformations and indicates a need for their improved recognition for the timely initiation of treatment.

Nosological and Theranostic Approach to Vascular Malformation through cfDNA NGS Liquid Biopsy

Several different nosological classifications have been used over time for vascular malformations (VMs) since clinical and pathological signs are largely overlapping. In a large proportion of cases, VMs are generated by somatic mosaicism in key genes, belonging to a few different molecular pathways. Therefore, molecular characterization may help in the understanding of the biological mechanisms related to the development of pathology. Tissue biopsy is not routinely included in the diagnostic path because of the need for fresh tissue specimens and the risk of bleeding. Bypassing the need for bioptic samples, we took advantage of the possibility of isolating cell-free DNA likely released by the affected tissues, to molecularly characterize 53 patients by cfDNA-NGS liquid biopsy. We found a good match between the identified variant and the clinical presentation. PIK3CA variants were found in 67% of Klippel Trenaunay Syndrome individuals; KRAS variants in 60% of arteriovenous malformations; MET was mutated in 75% of lymphovenous malformations. Our results demonstrate the power of cfDNA-NGS liquid biopsy in VMs clinical classification, diagnosis, and treatment. Indeed, tailored repurposing of pre-existing cancer drugs, such as PIK3CA, KRAS, and MET inhibitors, can be envisaged as adjuvant treatment, in addition to surgery and/or endovascular treatment, in the above-defined VMs categories, respectively.