You are all aware that if it is truly a sarcoid, it is a virus that causes them and, no matter what you do to the bump itself, all it takes is for the body's immune system to realize it is there and it is a stranger and it will fight and get it gone.
The treatments for those are all about getting the body to know it is there, irritate it enough so it quits being able to hide.
So, whatever we use or if we don't use anything, eventually they should leave, if the horse has a properly working immune system.
If they are growing where they can cause problems, vets generally want to be more aggressive there.
Here is a site with some information and pictures of the different kinds:
and some more information here, if a little dated:
"Currently, there is no effective therapy for the treatment of sarcoids. Some clinicians have reported pragmatic success with topical unlicensed applications (Knottenbelt & Walker, 1994). Other commonly employed treatments include cryotherapy, excision and local immune modulation (Goodrich et al., 1998).
Efficacy of different treatments is difficult to assess because most studies have not been controlled and are based on referral populations of horses treated at major clinics or veterinary hospitals. Such referral populations may not represent the overall tumour population in the field but a subset of fast growing, recurrent or multiple tumours that veterinary practitioners in the field have been unable to treat successfully. Conversely, many private practitioners treat sarcoids successfully by a policy of non-intervention, which again may represent a specific population of sarcoids that remain quiescent or the rare spontaneous regressors and there is some anecdotal evidence for this (Goodrich et al., 1998).
Sarcoids frequently display hyperproliferation or recurrence if treated by surgical excision, which has led some to speculate that this could be due to activation of latent BPV in apparently normal tissue surrounding the lesion. Martens et al. (2001a) used PCR to test for BPV in sarcoids removed by surgery and also tested apparently normal skin around the sarcoids. They found BPV in all of the sarcoids and also in the surrounding normal skin. The frequency of detection of BPV in the normal skin decreased as the resection margin was increased. They also found that animals with a surgical margin containing BPV had a greater probability to show local recurrence. These observations agree with the results of a study that examined the inducement of tumour development by trauma in an experimental model. Siegsmund et al. (1991) used a laboratory strain of the rodent Mastomys natalensis, which carries an endogenous latent papillomavirus (MnPV), to show that when the skin of these animals was irritated by scratching with glasspaper, hyperproliferation of the epidermis and amplification of viral DNA occurred, with virus-producing papillomas induced in 27 % of the animals."
OK, here is our sarcoid story - our TB got one on his ear a few years ago. It started out as a bump on the very edge of his ear. At first we thought it was an embedded tick. It gradually grew. We had vet look at it, he said it was a sarcoid, and recommended removing it in the fall, after fly season. It got bigger through the summer, eventually it looked like a golf ball on his ear, and would sometimes bleed a little. Just about the time we were going to set up the vet appt., one morning it was gone! We guess he had been rubbing in against something, and knocked it off. It hardly bled or left a scar at all. That was 5 or 6 years ago, it never came back.