Non-Surgical Management of Sarcoids in the Horse
The wide variety of treatments reported to be successful in the management of the equine sarcoid probably indicate that no one treatment is universally effective.
This aggressive malignant periocular sarcoid was treated with iridium 192 interstial brachytherapy. The outcome, below, was exceptionally good but it took over 12 months to reach the state shown and there were some side effects on the cornea and lens. These were, however, trivial to the horse and he was able to compete to the highest possible level.
The restrictions that apply in the management of sarcoid in terms of the variety of clinical / pathological type, the location and extent of individual tumours makes the choice of treatment somewhat easier. However, there are considerable limitations that apply in every case.
Suitable methods that can apply include radiation, which is widely regarded as the gold standard against which other methods can be compared. Beyond this a wide variety of topical and intralesional chemotherapy methods have been developed across the world.
Almost all reported methods of topical and intralesional chemotherapy have reported successes. Many of these have little evidence to support their use and many are patently useless. Immunological methods have been used for many years and these range from the illogical and inappropriate use of "autogenous vaccines" to the recently reported autografting of tissues. The induction of a strong local inflammatory and immunologic response through intralesional BCG administration has been used for many years with success, particularly around the eye regions.
Treatment selection must be considered very carefully and the best available method must be used on the first occasion. The problem with any treatment method is not the successes - these are accepted with gratitude of course, but failures of any treatment method results in a significant drop in the overall prognosis for the case.
Homeopathic methods are universally useless; these methods can be regarded as a direct exploitation of the vulnerable, the gullible and the disillusioned.
The treatment of the equine sarcoid remains a major challenge in equine practice since the prevalence of the tumour is high (up to 8% in some parts of the world). Furthermore, there are around 40 described treatments and this simply suggests (as we know!) that no one treatment is universally effective.
Treatments seem to have a variable rate of success when carried out by different veterinarians. Few extensive case series have been published but those that have been put in the public domain (Knottenbelt and Kelly, 2000) have confirmed the ongoing difficulty of management and the variability of results from any single modality.