Equine sarcoid: BCG immunotherapy compared to cryosurgery in a prospective randomised clinical trial

Abstract

A total of 30 horses with single or multiple sarcoid tumors of the skin were randomly divided into three treatment groups: (i) cryosurgical treatment, (ii) intralesional immunotherapy with a live BCG vaccine, (iii) intralesional immunotherapy with a BCG cell wall preparation. Complete tumour regression was obtained in all 10 cryosurgically treated horses, in 6 of 10 live BCG treated horses, and in 7 of 10 BCG cell wall treated horses. One live BCG and 2 BCG cell wall treated horses showed partial tumour regression of more than 50% of the tumour area. Eleven horses with sarcoid tumours were not eligible for random allocation in the trial because unfavourable site or size of the tumour precluded cryosurgical treatment. These animals were treated with BCG cell wall vaccine except for 1 animal, which was treated with live BCG. In 4 cases this treatment was combined with cytoreductive surgery of the tumour. In this prognostically unfavourable group 8 animals showed complete tumour regression and 3 animals did not respond. Regression after BCG immunotherapy appeared to correlate with size (larger tumours worse response) and localization of the sarcoid (less favourable results in the limb), and increase in peripheral blood leucocytes after the first injection. Horses with a positive delayed type hypersensitivity reaction to PPD before the start of treatment showed a tendency to more favourable prognosis than PPD negative horses. No correlation was present between regression and single or multiple presence of sarcoids, increase in body temperature after injection of BCG and the formation of specific antibodies to BCG. None of the cured animals have shown tumour recurrence 3 to 40 months following treatment.

Immunotherapy of bovine ocular squamous cell carcinoma by repeated intralesional injections of live bacillus Calmette-Guérin (BCG) or BCG cell walls

“…The results obtained with repeated local administration of BCG in superficial bladder cancer in humans [2, 3, 5, 13, 20-22, 26, 27] and in sarcoids in horses [16,23,28,29,33] stimulated the present study of the effect of repeated treatment of BOSCC with BCG. Moreover, in a previous study of Klein et al [17] it was suggested that the success of the therapy might be correlated with the ability of the immune system to generate long-lasting BCG-specific memory.…”

“…There was no recurrence after repeated treatment [16]. In our clinic repeated intralesional administration of BCG became the therapy of choice for equine sarcoids not located on the legs.…”

“…Repeated intralesional injections of BCG in horses with fibro-epithelial tumours (equine sarcoids) resulted in complete cure in 50%-90% of the animals [16,23,28,29,33]. There was no recurrence after repeated treatment [16].…”

A novel murine model for evaluating bovine papillomavirus prophylactics/therapeutics for equine sarcoid-like tumours

“…Therefore, vaccinations and immunotherapies have been explored that may stimulate the immune system to combat the causative viral infection. For instance, the Bacille de Calmette et Guérin (BCG) vaccination, is already used as an off-label treatment for peri-ocular sarcoids with a success rate of nearly 100 % (Klein et al, 1986). However, BCG is less effective on other parts of the body, including the ventral abdomen, which is most common locale for sarcoids (Bogaert et al, 2008a), and may induce severe side effects, including prolonged lymphangitis.…”

Intravesical and Intradermal Bacillus Calmette-Guérin Application

“…Immunostimulation and antitumor activity by the BCG-RIVM was observed both in experimental [14,19,21,34] and spontaneous animal tumors [17,18]. In man, this BCG preparation was studied as adjuvant immuno therapy in melanoma patients [7] and adjuvant therapy in bronchus carcinoma [12], The toxicity of the com bined intradermal and intravesical application of BCG-RIVM was investigated on normal and coagulated urothelium in the dog bladder [28].…”