Cryotherapy to treat benign skin tumours in conscious dogs

Background Cryotherapy can be used to treat benign skin lesions without general anaesthesia. This technique has only been described in anaesthetized dogs. Objective To describe the feasibility, safety and efficacy of cryotherapy to treat benign skin tumours in conscious dogs. Animals Twenty-five client-owned dogs with 52 skin tumours diagnosed as benign sebaceous neoplasia (46) or follicular cysts (six). Methods and materials Cryotherapy was performed in conscious dogs using a liquid nitrogen spray technique with a handheld spray-release system. If needed, cryotherapy was repeated every three to four weeks until complete cure was achieved or for a maximum of eight treatments. Effectiveness and adverse effects were recorded. Results Resolution was obtained for 29 of 52 lesions (57%) with a median number of one to two cryotherapy sessions. Eighteen of 52 (35%) lesions shrank to <0.1 cm. In one case, the tumour enlarged after cryotherapy, and histopathological examination of the excisional biopsy revealed an apocrine gland carcinoma. Pain and discomfort during the treatment were the most common adverse effects (33%). Conclusions and clinical importance In the present study, cryotherapy was possible in conscious dogs and proved to be effective to cure or reduce the size of benign sebaceous tumours and follicular cysts. The procedure is safe but the degree of pain during the treatment needs to be further investigated. Worsening of the lesion after cryotherapy suggests the need for surgical removal and histopathological examination.