Sarcoids are the most common skin tumour in horses, ponies and donkeys. They can appear almost anywhere on the body, and are often seen around the head, sheath, groin, belly and legs.

Sarcoids rarely spread inside the body, but they can affect your horse’s welfare and value. They often multiply over time and can become ulcerated or infected. Sarcoids in awkward places, such as around the eyes, over joints or where tack sits, can be harder to treat.

Our advice is to treat sarcoids early, while they’re small, rather than waiting to see what happens. Please don’t try home remedies or rub, tie or pick at a sarcoid: irritating it can make it grow faster or turn into a more aggressive type.

Asking us to look at a lump early usually gives your horse the best chance and saves time and money in the long run.

Can my horse catch sarcoids from other horses?

Sarcoids are linked to bovine papillomavirus (a virus also found in cattle), and some horses seem to be more likely to get them than others because of their genes. Flies are thought to help spread the virus between horses. Flies are also attracted to sarcoids, which can bother your horse, so good fly control is an important part of managing them.

What do sarcoids look like?

There are six main types of sarcoid: occult (flat, often a hairless or scaly patch), verrucous (warty), nodular (lumps under the skin), fibroblastic (fleshy and often ulcerated), mixed, and malevolent (a rare, aggressive type). Some stay the same for years, while others change from one type to another. Owners often spot the more obvious types, but the flat occult type can be easy to miss. We often find these during a routine visit or when we’re seeing your horse for something else.

How will my vet diagnose sarcoids?

Our vets can usually recognise a sarcoid by looking at it and feeling it. For many skin lumps we’d take a biopsy (a small tissue sample), but we usually avoid this with suspected sarcoids, because damaging the skin can make them worse. If we’re not sure, or the case is complicated, we may send photos and your horse’s history to a specialist for advice.

What are the treatment options?

No single treatment works for every sarcoid. The right choice depends on the type, size, number and position of the sarcoids, and on what suits you and your horse. Depending on your horse’s sarcoids, we may recommend one or more of the following:

• Monitoring: some small, inactive sarcoids are best watched closely rather than treated straight away.
• AW5 cream (formerly known as ‘Liverpool cream’): a strong anti-cancer cream, available only to vets through a specialist referral service (Equine Medical Solutions) after they’ve assessed your horse’s sarcoids. The cream is hazardous, so only a vet can apply it, usually over several visits at your yard. We’ll explain how to handle your horse safely between visits.
• Banding (ligation): for sarcoids with a narrow base or stalk, our vets can place a tight band around the base at your yard, using sedation and local anaesthetic where needed. This cuts off the blood supply, so the sarcoid dies and drops off over a few weeks, leaving a wound that needs to heal. Before banding, we check that the sarcoid doesn’t have a deeper root, and we may combine banding with cream treatment. Please never try banding or tying off a sarcoid yourself, as it can make it much worse.
• Referral to a specialist centre: for sarcoids that aren’t suitable for cream or banding, such as large sarcoids, those in difficult places or ones that have come back, we can refer your horse for other treatments, such as surgical or laser removal, or electrochemotherapy (an anti-cancer drug used together with short electrical pulses).

Every treatment has its own benefits, drawbacks and risk of the sarcoid coming back. We’ll talk you through the options before we agree a treatment plan with you.

If you’ve noticed a lump or patch you’re unsure about, call us on 01270 660014.