Treatment of equine sarcoids: A systematic review

Abstract

BackgroundThe sarcoid is the most common equine cutaneous neoplasm. Evidence‐based treatment of this condition is often lacking, and selection of treatment modality based on clinical experience or anecdotal evidence.ObjectivesTo assess the quality of the currently available best evidence regarding the treatment of the equine sarcoid.Study designSystematic review.MethodsIn compliance with PRISMA guidelines, literature searches were performed in PUBMED, Web of Science, CAB Abstracts, EMBASE (Ovid) and Scopus in April 2021. Included papers were required to describe an interventional study examining sarcoid treatment strategy, of level 4 evidence or greater. The case definition required confirmation of at least some included lesions on histopathology, and a minimum of 6 months of follow‐up was required on treated cases. Studies were assessed by two independent reviewers (KO, CD). Data extraction was performed manually, followed by risk of bias assessment. Methodological quality was assessed using the GRADE system.ResultsIn total, 10 studies were included in the review. Case definition was confirmed via histopathology in all included lesions in 60% of papers. Time to follow‐up was variably reported. Overall risk of bias ranged from ‘some concerns’ to ‘critical’. Reported sarcoid regression rate ranged from 28% to 100% on an individual sarcoid level, and 9%–100% on a whole horse level. Transient local inflammation was reported following most treatment strategies, with further adverse events reported infrequently.Main limitationsReview methodology excluded a large proportion of available literature regarding the equine sarcoid. Significant heterogeneity between included studies prevented quantitative synthesis and most included papers were at significant risk of bias, indirectness, and imprecision.ConclusionsThere is insufficient evidence currently available to recommend one sarcoid treatment over another. There is an urgent need for sufficiently powered, randomised, placebo‐controlled trials in order to allow more definitive comparison of the efficacy of different treatment strategies.

Retrospective study: Laser excision versus combined laser, cryotherapy and intralesional 5-fluorouracil in the treatment of equine sarcoids.

“…The lack of routinely accepted standardised outcome measure for the treatment of sarcoids makes comparison between studies very difficult. (Offer et al, 2024) Though these recurrence rates are marginally higher than those reported in the literature (sarcoid regression rates of 83-89% with sole laser excision), Compston et al, 2016) this is highly likely to be influenced by numerous factors, including greater length of follow up period in this study, and differences in case selection and treatment populations. These horses were all referred to the hospital for further evaluation and treatment, and by definition were positioned at the more severe end of sarcoid phenotype presentation.…”

A randomized placebo‐controlled double‐blinded study comparing oral and subcutaneous administration of mistletoe extract for the treatment of equine sarcoid disease

“…Although numerous treatments against ES disease are currently in widespread use, double-blinded placebo-controlled studies critically assessing the efficacy and sustainability are lacking for most of these treatment options. 45 The study design of the present investigation was not only placebo-controlled and randomized but also doubleblinded. Therefore, it fulfills every criterion for a rigorously controlled and unbiased investigation.…”

World Equine Veterinary Association Congress moves to Chile: A collection of articles for the South American practitioner

“…Offer et al . (2023) 14 revisa los méritos relativos y las tasas de regresión asociados a varios tratamientos contra sarcoides, pero concluye que hay insuficientes recomendaciones para evaluar uno sobre el otro en todas las situaciones, mientras Johnson et al . (2023) 15 explora las evolución de las aplicaciones de la terapia extracorporal por ondas de choque.…”

“…Nevertheless, the included reviews in this collection offer some pertinent information for the general practitioner. Offer et al 14 review the relative merits and regression rates associated with various sarcoid treatments, but conclude there are insufficient recommendations to rate one over the other in all situations, whilst Johnson et al 15 explore the evolving clinical applications of extracorporeal shockwave therapy. A practical take home message on maximising the diagnostic power of blood cultures was that although blood for this purpose is often taken during intravenous catheter placement for convenience, this may increase the potential for contamination and a non‐diagnostic result 16 …”