54
46TH
ANNUAL
CONGRESS
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THE
SAEVA
SKUKUZA
16-‐20
FEBRUARY
2014
and anti-inflammatories (NSAIDs), which are continued for 3-5 days. Tetanus
prophylaxis is administered if indicated.
As with any tumour, frequent monitoring is essential. Animals treated should be
examined at four-week intervals, and additional beads implanted as necessary until
the tumour has disappeared and no regrowth is evident.
Complications encountered include erythema and inflammation, the occasional
generalised cellulitis, wound drainage and dehiscence as well as inflammation of
adjacent structures. Care should be taken when implanting cisplatin beads near the
eye, as corneal ulceration and general inflammation can result in permanent eye
damage necessitating enucleation.6 In my experience, cisplatin beads should not be
placed closer than 2 cm to the eye.
In a recent retrospective study performed at the University Veterinary Teaching
Hospital, Sydney, 21 horses over a four-year period were treated with cisplatin
beads (n=19) or cisplatin injections (n=2). The tumour types included sarcoids (15),
squamous cell carcinomas (4), melanoma (1) and low-grade sarcoma (1). The
cisplatin treatment was used in combination with surgery, except in cases where
repeat cisplatin treatment was required post operatively.9
Complications included local tissue inflammation and swelling (5), discharge from
incision (6), cellulitis (2), incisional dehiscence (2) and hair colour change (1). No
clinically apparent reaction to the cisplatin was noted in four horses. In 17 patients
(16 sarcoids, and 1 melanoma) no evidence of tumour recurrence was reported after
6 months or longer. Recurrence of the tumour was reported in five of the 21
horses, including one horse that did not show any response to treatment. Of these
horses with recurrence or poor response, 4 of these tumours were squamous cell
carcinomas, and one was a sarcoid. Three of the horses with squamous cell
carcinoma were euthanatized 6 weeks, 12 weeks and 14 months following
treatment. The other horse with SCC required four additional bead implantations
over the last 4 years.9 These results are consistent with previous reports that
suggest squamous cell carcinomas are more likely to occur than other tumour
types.7 Cosmetic outcome was deemed good by owners in 15/17 cases.9
Handling any chemotherapeutic requires some basic precautions. Chemotherapy
gloves or double latex gloves are essential for implantation of the beads. Handling
the wound following implantation should be avoided; if absolutely nece ssary double
latex gloves or chemotherapy gloves should be worn. Using absorbable sutures is
important to minimise exposure to the beads. Contaminated disposable materials
must be disposed of in biohazardous waste.8 Regional occupational health and safety
guidelines and standards should be reviewed and adhered to before handling any
chemotherapeutic agent.
Cisplatin beads offer a practical alternative for the treatment of cutaneous tumours
in horses, and should be considered if adjunctive therapy is indicated.
References:
1.
Scott DW, Miller WJ. Neoplastic and non-neoplastic tumors. In: Scott DW, Miller WJ, eds.
Equine Dermatology. St Louis, MO: Saunders, 2003; 698-795.
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