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Oral sirolimus therapy for patients with complex low-flow vascular malformations
Rebecca Nisbet1, Calver Pang2, Nicholas Evans3
1Royal Free London Vascular Anomalies Centre, Royal Free London NHS Foundation Trust, London, UK; School of Medicine, University of Leeds, Leeds, UK.
Background:
The evidence on the efficacy and safety of sirolimus therapy in patients with low-flow vascular malformations (LFVMs) has indicated its potential benefit in extensive and complicated lesions. This study aimed to assess the efficacy and safety of oral sirolimus therapy on complex LFVM patients when standard treatment alone was inadequate.
Methods:
This was a retrospective study of all adult patients with diagnosed LFVMs who were treated with oral sirolimus where standard therapy was inadequate in a single specialist center from May 1, 2016, to April 30, 2023. Demographic and clinical data including patient reported responses, visual analogue scores for pain and adverse effects, and quality of life (QoL) scores (Short Form-36) were reviewed.
Results:
We included 55 LFVM patients (14 with syndromic disease and 41 with nonsyndromic) with a median age of 41 years (range, 23-72 years). While on sirolimus, 32 patients (58.2%) experienced some improvement with a nonsignificant higher percentage of nonsyndromic patients experiencing some improvements (P = .6478). There was a nonsignificant improvement in the quality of life scores for physical problems, energy/fatigue, and pain. There was also a nonsignificant increase in anxiety and depression scores. There was a significant decrease in the lesion size (P = .0004). Two patients reported a cessation of cellulitis episodes, and eight patients reported a partial or complete reduction in bleeding from their malformation or rectal bleeding. The most common side effects reported were mouth ulcers (54.5%), fatigue (29.1%), headache (25.5%), gastrointestinal problems (25.5%), and rash (12.7%); only five patients (9.1%) did not report any side effects. No significant difference was found between the side effects reported by syndromic and nonsyndromic patients.
Conclusions:
Oral sirolimus therapy was clinically effective and safe in patients with complex LFVMs when standard therapy alone was inadequate. Further studies with longer follow-up are needed to evaluate oral sirolimus therapy in LFVM patients.
