Meet Bailey... (Sarcoids)
Bailey is a seven year old, Anglo Arab gelding with a promising showing career ahead of him. He has had a very successful novice season competing hack and Anglo/part bred Arab classes culminating in Reserve British National Champion Ridden Anglo Arab 2008. His owner was very concerned, as he had recently developed a number of unusual skin lumps in many different places all over his body.
Skin lumps can appear for a number of reasons, and their size, shape, the place at which they are found on the body and how quickly they have appeared are all very important considerations. These factors act as small clues in identifying the lumps, why they have appeared and how they can be treated. When Bailey was examined in January 2009, he had a large number of rough, raised areas of hairless skin, which were of all different shapes and sizes on his neck and face. He also had several small, red, marble-shaped hairless lumps under his skin, between his hind legs.
Bailey’s skin lumps were identified to be sarcoids. Sarcoids are a form of skin cancer that is, unfortunately, frequently seen in horses. Although sarcoids can be found on any area of the body, they often appear on hairless skin and on areas where horses tend to be bitten by flies, for example on their face, between their forelegs and on the insides of their hind legs, as in Bailey’s case. Sarcoids can also appear on wounds where they can slow down or even stop wounds from healing. The reason as to why horses develop sarcoids is not fully understood, but it is thought that flies transmit cells that are infected with a virus called ‘bovine papilloma virus’ to horses and this triggers the sarcoid to grow. The virus has absolutely no connection to horses being kept alongside cows, despite its name.
Sarcoids appear in all different shapes and sizes and are categorised into six types: nodular, verrucose, occult, fibroblastic, malevolent and mixed. Bailey had developed nodular sarcoids (which look like red marbles) between his hind legs and a number of mixed-type sarcoids (the rough raised areas of skin) on both sides of his neck, face and at the base of his right ear.
It is very important to consider treatment for sarcoids. Untreated sarcoids will grow bigger with time and can be a welfare consideration in horses. Sarcoids can easily devalue a horse, reduce its performance and even make the horse impossible to sell. Some horses can suffer sarcoids to such as extent that they are put to sleep on welfare grounds.
There are many different treatment options available for different types of sarcoids. Our first step was to carefully examine each of Bailey’s sarcoids to identify which types they were so that we could devise a treatment plan. Sarcoid treatment is not only quite expensive, but it is also a large under-taking for Bailey and his owner to experience. There is no guarantee that any of the treatment options will be successful in removing the sarcoids and there is always a chance that the sarcoids could re-grow at a later point in time. It is also important to consider that the treatment could leave scars, which in Bailey’s case would not bear well for his showing career.
It was decided that the best way to treat the nodular sarcoids on the insides of Bailey’s hind legs, would be to ‘ligate’ them. Ligation involves placing a small but extremely strong rubber band around the base of each of the nodular-type of sarcoids. This method of treatment cuts off the sarcoid’s blood supply and after several weeks the sarcoid drops off. We decided that the best way of treating the mixed-types of sarcoids on Bailey’s neck and face would be with ‘AW4 cream’. In order to do this we had to photograph all of the sarcoids that we were intending to treat, and then send them to Professor Knottenbelt at the University of Liverpool who is an expert in the treatment of sarcoids amongst other things. The University of Liverpool Sarcoid Department supplies the AW4 cream. The cream is ‘cytotoxic’ which means that it kills any body cells, regardless as to whether they are healthy or diseased. Consequently it was very important that Bailey stood still whilst the cream was applied to avoid treating any healthy skin cells surrounding the sarcoids. Several applications of the cream were needed over a number of weeks to complete the full course of treatment.
Other therapies that are available for sarcoid treatment include surgical removal, cryosurgery, laser therapy, and BCG treatment. The location of Bailey’s sarcoids would make surgical removal, cryosurgery and laser therapy very difficult to carry out and there would be a high risk of scarring. BCG treatment was not an appropriate choice for treating Bailey, and it is usually used as a last resort to treat sarcoids around horses’ eyes. It involves injecting a series of BCG injections directly into the sarcoid. This is a very risky procedure, as horses can suffer potentially fatal adverse reactions to the injections.
After several weeks of treatment, the nodular-type sarcoids that had been ligated had dropped off and the skin was healing well. The mixed-type sarcoids that were treated with the cytotoxic cream made excellent progress. The larger sarcoids reduced in size and the skin is healing very well around the areas where smaller sized sarcoids were found. Given the extent of Bailey’s sarcoids and the aggressive treatment schedule that he had to endure, we are very pleased with his progress. There is lots of evidence to show that after sarcoids have been treated, competition horses show an improvement in their performance. By May 2009 Bailey’s skin was fully healed and he and his owner enjoyed another busy showing season this year.