Treatment of Dogs With Oral Melanoma Recurrence by Diode Laser Excision

Abstract

Introduction: Treatment of oral melanomas utilizes the surgical excision-resection (Culp et al., 2013) and/or radiation therapy (Proulx et al., 2003), chemotherapy with carboplatin (Brockley et al., 2013), immunotherapy (Ottnod et al., 2013). Treatment based on surgical excision is usually palliative (Freeman et al., 2003). Aims: In the literature even though there are data concerning the prognosis of oral melanomas in dogs after surgery, are missing data after laser excision. Taking into account these findings we wished to present our experience regarding three cases of oral melanoma recurrence and immediate and long term laser surgery results. Materials and Methods: The casuistry consisted of three dogs with recurrent oral malignant melanomas, subjected to surgical reintervention. The initial diagnosis was melanotic melanoma in stage I or II. The animals were brought back at different time intervals from originally excision with electric scalpel. Before reintervention, dogs were subjected to clinical, paraclinical exam and biopsy. Excision of the tumor mass was made with an optical fiber hawing a diameter of 400µm, at a power of 10W and a wavelength of 940 nm with a diode laser. At 1, 2, 3, 6 and 12 months after laser reintervention the dogs were reexamined. Results: Average time in which appeared canine oral melanoma relapse was 58.6 days. After reexamination all cases where reinstatement in stage I. Operators times were held in conditions of comfort with wide access, minimum bleeding, effective hemostasis. After surgery at 24 hours on the intervention place a slight local redness, without swelling and bleeding was observed. Palpation revealed initially also a slight local sensitivity which completely disappeared in 48 hours. There were no grasping and chewing disturbances. Macroscopic healing occurred in 7-9 days. At last recheck performed at 12 months there were no evidences of tumour recurrence or metastasis. Conclusion: Diode laser excision of oral malignant melanoma in dogs can be an alternative palliative procedure to invasive surgical resection procedures. The average of free recurrence and metastasis time after laser surgery has exceeded 360 days in these three cases.