An introduction to Sarcoids

What are sarcoids?

Sarcoids are benign skin tumours that can be found in horses, donkeys and mules, they are generally not life threatening but do destruct the skin cells that are surrounding them. They appear in different forms on a horse and are most commonly found on the abdomen, inside the backs of legs, the chest and around the ears and eyes. Normally at the sight of previous traumas and where flies congregate. Even though there are 6 different types of sarcoids they all start small and grow at different rates, when they enlarge the skin may ulcerate that can attract flies and cause an open sore.

Why does a horse get sarcoids?

Sarcoids are caused by an infection the virus Bovine Papilloma Virus (BPV), it is a virus that originates from cattle but is spread by flies. All horses may be infected by BPV in their life, however not all of them will be susceptible to the virus and present with sarcoid growth.

How do I know if my horse has sarcoids?

Not all lesions that appear on the skin are sarcoids so a vet should be able to diagnosis whether it is a sarcoid or any other skin problem.  If the vet is unsure they can take a biopsy to confirm the diagnosis, this is the last resort diagnosis as a biopsy is invasive. As to know if your horse has the gene that makes them susceptible to sarcoids there is a genetic test that can be carried out however these are not used very often by vets as they can be inconclusive and are expensive to run.

How can I prevent sarcoids?

There is no easy prevention of sarcoids as there has not yet been a vaccine developed for the disease. Making sure your horse’s immune system is at its strongest in order to help fight the virus and boost the immune system.

How are sarcoids treated?

There are many ways that sarcoids can be treated and as they all react differently to treatment. The main way of treatment is the use of Liverpool cream, a chemotherapy cream created at the University of Liverpool. This takes place over a number of weeks and can become expensive as the  cream can only be applied by a vet.  The cream is applied every day for a week or every other day for 2 weeks although this may change on a case by case basis.  It is method that makes the sarcoid look worse before becoming better, as it kills all the cells from the area that it is applied to and after a long period of time the sarcoid falls off along with all of the skin cells containing the virus. This then leaves a raw patch of skin exposed (see picture on right), which is why the best time for Liverpool treatment is in the winter where no flies can infect the exposed patch of skin.  There  are many success stories of it fully getting rid of sarcoids although others say that it returned, again reiterating that every sarcoid is different and may have a different reaction to treatment.

Another way is rubber banding this is specific to certain types of sarcoids as it is not possible to get a band around every one as some lie flat. But if a band can be placed around it, then the circulation to the sarcoid will slowly be cut off until it dies and falls off.  Along the same lines as this,  there is also laser surgery and Cryosurgery.  They all aim to remove the sarcoid cleanly leaving no trace.

Laser is the least invasive using lasers to remove it, Cryosurgery uses a repeated rapid freezing method which is time consuming. Alternatively there are homeopathy treatments that have worked in some cases but also have limited success as they tend to need harder treatments to remove the sarcoids. However there has been proven success with Bloodroot treatment which is a plant extract, used in a similar way to Liverpool cream, the picture on the left shows a pony who had bloodroot treatment and the results after 3 weeks (2 weeks of treatment with 1 week off in between), for this pony however, the treatment did not completely get rid of it.

Do I need to treat my horse’s sarcoids?

Not necessarily if the lesion is not getting bigger or is in a place that will not affect the horse then it is up to you if you leave it. However when the sarcoid is smaller it is easier and quicker to treat so early treatment is recommended. Discuss with your vet which is the best method of removing for your horse and its type of sarcoid.