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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.
Insights
Oral sirolimus effectively treated complex low-flow vascular malformations (LFVMs) when standard therapies failed, significantly reducing lesion size. While side effects were common, the treatment proved safe and beneficial for these challenging LFVM cases.
Area of Science:
- Vascular Biology
- Pharmacology
- Dermatology
Background:
- Low-flow vascular malformations (LFVMs) present significant challenges, particularly in extensive or complicated cases.
- Existing evidence suggests sirolimus may benefit patients with complex LFVMs.
- Standard treatments are often inadequate for severe LFVM presentations.
Purpose of the Study:
- To evaluate the efficacy and safety of oral sirolimus therapy.
- To assess treatment outcomes in adult patients with complex LFVMs where standard therapy was insufficient.
Main Methods:
- Retrospective study of 55 adult LFVM patients treated with oral sirolimus from May 2016 to April 2023.
- Data collected included patient-reported outcomes, pain scores, quality of life (SF-36), and adverse effects.
- Analysis compared outcomes between syndromic and nonsyndromic patients.
Main Results:
- 58.2% of patients showed some improvement, with a significant decrease in lesion size (P = .0004).
- Quality of life scores showed nonsignificant improvements in physical function, energy, and pain, but increased anxiety/depression.
- Common side effects included mouth ulcers (54.5%) and fatigue (29.1%); 9.1% reported no side effects.
Conclusions:
- Oral sirolimus is clinically effective and safe for complex LFVMs unresponsive to standard therapy.
- The treatment demonstrated a significant reduction in lesion size.
- Further long-term studies are warranted to fully elucidate the role of sirolimus in LFVM management.
