Chelliah MP, et al. - The effectiveness and tolerability of sirolimus as adjuvant therapy for endovascular embolization in managing complicated extracranial head and neck arteriovenous malformations were evaluated. A mammalian target of rapamycin inhibitor was seen to be beneficial as adjuvant therapy for surgical embolization of complex, extracranial head and neck arteriovenous malformations.

Methods

• Experts conducted this case series on six patients with extracranial head and neck arteriovenous malformations treated from January 1, 2013 to December 31, 2017 at a multidisciplinary vascular anomalies clinic within Stanford Hospital and Clinics.
• Intervention included the initiation of sirolimus at least 1 month before endovascular embolization, targeting a trough level of 10 to 15 ng/mL throughout the course of the endovascular embolization series and continued for at least 1 month after the series.
• They evaluated the clinical manifestations, disease progression, and overall response to treatment through clinical evaluation and radiographic imaging.

Results

• Findings suggested that all six patients (four male and two female patients; mean age, 24.5 years [range, 9-44 years]) responded favorably to the combination of sirolimus therapy followed by endovascular embolization; four patients exhibited a near-complete response.
• Nineteen months (range, 6-40 months) was the median duration of follow-up.
• Sirolimus was discontinued by one patient soon after embolization and experienced regrowth of the arteriovenous malformation after 1 year; this patient resumed sirolimus, which stabilized his disease for more than 2 years.
• Four patients demonstrated mild adverse effects.
• Results demonstrated that in all patients, the combination therapy was well-tolerated.
• Skin ulceration following embolization was seen in one patient and required surgical debridement.
• Pulmonary microthrombi after embolization with cyanoacrylate glue developed in another patient that resolved with a short course of anti-inflammatory therapy.