Sarcoids are the bane of many horse owners lives. They are difficult to treat, can require careful management and often lowers a horses worth. Once they have one, they often get more. Not long after owning Scottie he developed a sarcoid on his sheath. Over the next few years he developed a few more sarcoids. Around the time Scottie developed sarcoids, I was working on a sarcoid project at University, so I was able to do a lot of research into what sarcoids are and the best way to treat them.
What are sarcoids?
Sarcoids are skin tumours believed to be caused by the Bovine Papilloma Virus. They can be on or below the surface of the skin, but only ever affect the skin. Therefore they will not spread to other organs like other forms of cancer. They affect horses all over the world and affect 6-7% of the UK Equine population and usually first occur in horses between 2 and 10 years of age. They can occur anywhere on the body, but are most commonly found on the face, groin and girth areas. It is believed they first form where the skin is thin, normally areas where flies feed from.
There is no evidence for sarcoids being heritable. However, there are several different studies to show that horses can be genetically predisposed to sarcoids. Jandova et al found that sarcoid development is linked to chromosomal regions ECA 20, ECA 23 and ECA 25. These regions include genes for virus replication and host immune response and therefore could affect how the horse deals with the Bovine Papilloma Virus. Their research also suggested that the heritability of this predisposition to sarcoids is around 8-21%.
What do sarcoids look like?
The appearance of a sarcoid is determined by the type of sarcoid. Many appear as bald, wart like growths. However some grow under the skin and appear as a small lump under the surface of the skin. There are 6 different types of sarcoid which vary in appearance and activity:
Normally appear as small round bald patch or area of poor/different quality coat. They are often mistake for other things such as ringworm or rub marks and most commonly appear on face, groin and armpits. Any interference (even accidental) often results in transforming into a more serious form of sarcoid.
Normally have a warty appearance, being grey and scaly. There is usually hair loss in the area, but might just be decrease in quality of the coat. They are most common on the face, groin, arm pit and sheath. As with the Occult sarcoid, they are often mistaken for other skin conditions including ringworm and often deteriorate into a more serious form of tumour if interfered with.
Nodular sarcoids form under the skin and are often mistake for cysts and insect bites. They are most commonly found on the eyelid, groin, inner thigh and armpit. If there are multiple they can often form together to look like a bunch of grapes. These tumours are very problematic in the eyelid as they often have extensive roots.
There are two main types based on the skin involvement:
– Type A have no skin involvement, meaning you can manipulated them separately to the skin. They tend to be found in the girth areas where the skin is thicker and they have been unable to get through the skin. The skin may lose hair in the area.
– Type B does have skin involvement, meaning you can either see them or feel them when manipulating the skin. The skin above is often hairless resembling a verrucous lesion and if it becomes damaged can quickly develop into a fibroblastic tumour.
This type of sarcoid often develops from less serious types after damage. They can occur anywhere on the body, including on the site of an injury. Fibroblastic tumours are also commonly bleed easily and have a wet/scabby surface.
There are two main types of fibroblastic tumour:
– Pedunculated have a thin stalk with a large growth on the end and may or may not have a root.
– Sessile have a broad, wide base.
Mixed sarcoid is the diagnosis given to an area which has two or more types of sarcoid present without a single type being dominant. They are most commonly found on the head, groin and armpit.
Malignant sarcoids are rare, but most commonly found on the face, armpit and groin. Malignant sarcoids have only recently been classified as extensive local or wide spread lesions through the skin and subcutaneous tissue. Large lesions are often misdiagnosed as malignant, but it is not the size but the extension.
This is a very aggressive type of tumour and unlike other forms it will not cure itself. There is currently no treatment, only management and improvement. It is believed that it can be caused by incomplete treatment of other/earlier lesions.
Can sarcoids kill a horse?
Sarcoids rarely directly affect the health of the horse,. However, depending on size, location and the number they can become sore, irritated and have been known to bleed. Larger tumours are likely to get caught or put pressure on the surrounding tissue. This can cause problems on areas around the eyes or on the sheath. Flies are also drawn to sarcoids which can cause more irritation and infection. However, the worst thing about sarcoids is how difficult they are to treat. Each horse and sarcoid reacts differently to treatment and once one treatment has failed, prognosis for any future treatment drops to around 40%.
Sarcoids are really difficult to treat in horses. Not only does treatment tend to have a fairly low success rate, but often they react badly to treatment, making them worse. So much so, that many vets will only recommend treating them if they are causing the horse a problem, ie: are under the girth and get irritated. Many horse owners instead choose to manage the sarcoids or try home remedies.
How to choose a sarcoid treatment?
If you have decided you want to treat the sarcoid, there are several factors to consider when deciding what type of treatment to use.
- Tumour type and behaviour
- Tumour size
- Time between tumour forming and treatment
- Owner and horse compliance
- Facilities and expertise
What treatments are available for sarcoids?
There are over 40 known treatments for sarcoids, proving that there is no one easy way to treat them. Each method will work best for certain types of sarcoid and will have it’s own risks and complications. These are some of the most used:
- Surgical Removal
Surgery is often chosen for small sarcoids however it has a high failure rate; success rate is higher after using other treatments first. There are procedures which can be taken to reduce risk of return. Nodular lesions on the thigh and groin region respond best to surgery.
This method consists of banding the sarcoids so the blood supply is cut of and they fall off. It should only be used on sarcoids which do not have a root formation and can be dangerous if they do have a root. This method is often used by owners and causes more problems.
Otherwise known as freezing. This method only works for small, shallow lesions. It is very time consuming as each sarcoid needs to be frozen and thawed at least 3 times. There is also a high rate of reoccurrence.
- Immune Methods
This method works well for nodular and fibroblastic lesions around the eyes. It involves injecting the human BCG injection directly into the sarcoid with a pressure syringe. Should not be used on the limbs as usually makes them much worse. There is a risk that the horse will react badly to the protein in the injection.
Chemotherapy usually consists of injecting cytotoxins or 5-Fluoro-urcail directly into the sarcoid. It is often considered one of the best methods of treatment; however it is only suitable for a small number or sarcoids and the chemicals used are potentially harmful to the vet.
- Topical Cytotoxic Therapy
Only available to vets for individual horses. It is very penetrative and sarcoids often get worse before getting better, causing the horse swelling and possible pain. Pain killers are often needed after treatment.
- 5-Fluoro-uracil cream
Effective on superficial occult sarcoids or as pre-treatment to surgery. It is only available by prescription.
- Topical Adjunctive Agents
Adjunctive treatments are treatments to use alongside other methods. There are 3 types that are said to work but still being researched and tested. These are:
– Exterra cream, a mixture of plant extras and chemicals available in the US, prescription only.
– Imiquimod, available for topical use on humans. Seems to be effective on some types of superficial sarcoids.
– Retinoid drugs, currently being tested by Liverpool University. Works well for occult but rarely works as the only treatment.
- Photodynamic Therapy
So far only tested on a small number of horses but seems effective on small isolated lesions. This method involves the cells absorbing a photodynamic chemical and then using specific light intensity and wavelength to activate the chemical and damaging the cells. It has limited use.
- Laser Surgery
The chance of reoccurrence in horses with
These treatments are considered useless by the scientific side of the industry, with there being absolutely no evidence for them working. However, many horse owners swear by herbal treatments for sarcoids, often turning to them after conventional treatment failed.
Treating sarcoids with turmeric
Feeding turmeric is on on the methods horse owners swear by for clearing up sarcoids. The idea behind this is that turmeric boosts the immune system which helps the body fight the sarcoid. There is absolutely no research to back this idea up. But feeding turmeric should not do your horse any harm at all and won’t make the sarcoid any worse. So if the sarcoid doesn’t need veterinary treatment, but you want to get rid of it, feeding turmeric might be a good thing to try for you. I tried Scottie on turmeric for over a year and saw no changes in his sarcoids, but I have seen good results in other horses.
If your horses sarcoids aren’t causing them any problems, you might be better off just managing them rather than treating them and risking making them worse. Making sure your horse has a balanced diet and protection from flies can be enough to maintain and potentially clear up your horses sarcoids.
Check your horses diet
There have been suggestions that boosting your horses immune system can help them fight sarcoids. Therefore making sure your horse is getting everything they need can help boost their immune system. I tried all sorts of home remedies with Scottie from turmeric to sarcoid supplements. But it was only once I switched him to a feed balancer rather than his conditioning cubes that one by one all his sarcoids cleared up. Nearly 4 years on we haven’t had any new ones.
Protect the sarcoids from flies
Flies are often drawn to sarcoids, biting them and irritating them. Unsurprisingly, this can make the sarcoids worse so you should try your best to keep the flies off them. If you can’t cover them with a fly rug or mask, you can cover them in a barrier cream such as sudacream.
Can you prevent your horse developing sarcoids?
Sarcoids can be a really hard thing to prevent but since they are believed to be carried by flies, anything you can do to protect your horse from flies will help. But unless there is already a horse on your yard/nearby with sarcoids or cows in the area, I wouldn’t be too worried about them developing sarcoids.
Should you buy a horse with sarcoids?
I think it really depends on the horse and the sarcoids. If the sarcoids are in a place where it shouldn’t cause the horse a problem and the horse is what you are looking for, I don’t think you should be put off. But if the sarcoids are particularly large or in an awkward area such as under the girth, I would question it. It is also worth remembering that you won’t be insured for any treatment your horse may need in future for these sarcoids.
When Scottie first developed a sarcoid I spoke to several different vets who all gave me different opinions on what I should do. Since it hadn’t grown since I had noticed it and it was out of the way, I decided to leave it alone and just watch it. More recently I have noticed a few patches of skin I think may develop into new sarcoids; again they are in out of the way and not worth treating as they are. I have therefore decided to go down the herbal route. I have started feeding turmeric as it was heavily recommended and I take the view of it is cheap and won’t make them any worse, whereas conventional medicine is expensive and there is a high risk of future problems.
As there is no universal treatment for sarcoids, there is still continuing research into new or improving treatment. Knotten at the University of Liverpool is currently one of the top scientists working on sarcoids and sarcoid treatment. One of the current best treatments for sarcoids is Liverpool cream, a cytotoxic cream developed by the University of Liverpool. Since there are so many owners swearing by herbal treatments and the fact that one of the tried and tested adjunctive treatments is based on herbal extracts, this could be a route for further research.
Last Updated on 14/01/2022