Equine sarcoid

The Equine sarcoid (ES) is a skin tumor in horses, donkeys, mules and zebras occurs. It is not to be confused with equine sarcoidosis . Since this tumor does not tend to metastases in the internal organs, but sometimes grows expansively and usually relapses after operations , it is referred to as semimalignant . Horses of all ages and races are affected. Usually it is only a cosmetic problem, but in an unfavorable position ( saddle position ) it can also lead to the horse being unable to ride. The tumor can appear singly ( solitary ) or in several places at the same time ( multiple ).

root cause

Equine sarcoid is caused by a cattle papillomavirus . There are geographical differences in the frequency of detection of bovine papillomavirus type 1 (BPV-1) and type 2 (BPV-2). In Europe, BPV-1 is found more frequently, in around 20% of cases also BPV-2. In the USA, BPV-1 and -2 are sometimes observed equally often. The DNA of these viruses can be detected in up to 100% of all tumors. In addition, parts of the virus genome can be detected in the blood of affected equidae.

A genetic predisposition has been described for the Quarter Horse , Arabian, and Appaloosa .

Clinical picture

Occult sarcoid (hairless area on the left) and a nodular sarcoid (right) in the immediate vicinity.

The equine sarcoid occurs more frequently on the head (eyes, corners of the mouth, base of the ears), the armpits and inner thighs, and on the prepuce . Different types of tumors can occur. According to Pascoe and Knottenbelt, six types can be distinguished:

• Type 1: The occult sarcoid: It appears as a mostly hairless, slightly raised and sometimes slightly nodular and hyperkeratotic increase in circumference.
• Type 2: The verrucous sarcoid: It appears as a wart-like increase in circumference with hyperkeratosis .
• Type 3: The nodular sarcoid: It appears as a subcutaneous lump of various sizes and can be pedunculated. The overlying skin is mostly hairless, but intact.
• Type 4: The fibroblastic sarcoid: It appears cauliflower-like, with an ulcerated surface and serous exudation . It can also be stalked.
• Type 5: The mixed sarcoid: It shows appearances of verrucous, nodular and fibroblastic sarcoid.
• Type 6: The malevolent sarcoid: It often appears after multiple trauma and can infiltrate the lymphatic system. You can then see nodes in their course.

Both after removal and spontaneously, the first-mentioned, easy types can transform into difficult types.

treatment

So far, numerous treatment options have been available for the therapy of equine sarcoid, but they are mostly ineffective. The spectrum includes surgical distances ( cryosurgery , laser surgery , electrosurgery ), chemotherapeutic treatment or vaccination with Bacillus Calmette-Guérin , a vaccine against tuberculosis. A combination of these forms of therapy is also described.

Radiation therapy, either as tele- or brachytherapy, has the best chances of recovery with over 80–90% . The latter form of therapy has also been available in Germany since 2009. The former has been in a facility in Linsengericht / Hessen since 2017. This form of therapy is limited by the costs for self-payers, so that it is mainly used for smaller lesions and those where other procedures fail. Animal owners with surgery insurance have the option of assuming the costs for radiation therapy.

One study describes the successful treatment of equine sarcoids by local acyclovir application, which is carried out daily for several months. The treatment responded in all of the 22 horses examined, in 70% the sarcoids disappeared completely, in the remaining 30% they were at least significantly smaller. The sarcoids, which had completely regressed, did not reappear for many months afterwards.

swell

• O. Dietz, B. Huskamp: Manual horse practice . Volume 2, Enke Verlag, p. 250.
• JP Teifke, E. Weiss: Detection of bovine papillomavirus DNA in equine sarcoids using the polymerase chain reaction (PCR). In: Berl Munch Tierarztl Wochenschr. 104 (6), 1991, pp. 185-187.
• L. Nasir, SW Reid: Bovine papillomaviral gene expression in equine sarcoid tumors. In: Virus Res. 61 (2), 1999, pp. 171-175.
• L. Goodrich et al: Equine sarcoids. In: Vet Clin North Am Equine Pract. 14 (3), 1998, pp. 607-623, vii.
• R. Pascoe, D. Knottenbelt: Manual of equine Dermatology. Verlag WB Saunders, pp. 244-248.
• G. Chambers, VA Ellsmore, PA O'Brien, SWJ Reid, S. Love, MS Campo, L. Nasir: Association of bovine papillomavirus with the equine sarcoid. In: Journal of General Virology. 84, 2003, pp. 1055-1062.
• Z. Yuan, A. Gallagher, EA Gault, MS Campo, L. Nasir: Bovine papillomavirus infection in equine sarcoids and in bovine bladder cancers. In: The Veterinary Journal. Volume 174, Issue 3, 2007, pp. 599-604.
• S. Brandt, R. Haralambus, A. Schoster, R. Kirnbauer, C. Stanek: Peripheral blood mononuclear cells represent a reservoir of bovine papillomavirus DNA in sarcoid-affected equines. In: Journal of General Virology. 89, 2008, pp. 1390-1395.

Individual evidence

1. ^ HO Mohammed, WC Rebhun, DF Antczak: Factors associated with the risk of developing sarcoid tumors in horses . Equine Vet J 1992; 24: 165-168. DOI 10.1111 / j.2042-3306.1992.tb02808.x
2. ↑ Cancer therapy in horses with the linear accelerator , accessed on March 23, 2020, 11:35 a.m.
3. ^ Reginald R. Pascoe, Derek C. Knottenbelt: Manual of Equine Dermatology . Elsevier, Oxford 1996, ISBN 0-7020-1968-2 , p. 252.
4. ↑ Silvia Stadler: Successful treatment of Equine Sarcoids by topical Aciclovir application. Dissertation . Vet. Med. Univ. Vienna, 2010.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !