Sümeyye Toyga(a), Hazal Öztürk Gürgen(a), E. Handan Zeren(b), Evrim Egeden(c), Özlem Calp(c)
(a)İstanbul Üniversitesi-Cerrahpaşa Veteriner Fakültesi, Patoloji Anabilim Dalı, Büyükçekmece, 34500 İstanbul, Türkiye
(b)Acıbadem Mehmet Ali Aydınlar Üniversitesi Tıp Fakültesi, Patoloji Anabilim Dalı, Ataşehir, 34758 İstanbul, Türkiye
(c)Ada Veteriner Polikliniği, Beşiktaş, 34330 İstanbul, Türkiye
Oral malign melanoma is the most commonly diagnosed tumor in the oral cavity of dogs. Successful results for BRAF gene mutations have been achieved in human medicine in the diagnosis of this neoplasia and in targeted treatment attempts. In this case report, it is aimed to present the prognostic evaluation of the patient who was detected to be BRAF V600E immunopositive.
A ten year old male Labrador dog was brought to the clinic with the complaint of a mass in the right upper jaw. In the clinical examination, a dark necrotic mass was detected in the oral cavity, rostral part of the right maxillary alveolar process, adjacent to the lateral canine tooth. Later, the mass, which was totally extirpated, was sent to the pathology laboratory for histopathological and immunohistochemical evaluations with S-100, Melan-A, BRAF V600E and CD117 antibodies.
The case was diagnosed with malignant melanoma as a result of histopathological evaluation. BRAF V600E and S-100 immunopositivity were detected. For the patient with lymphatic involvement which was detected on computed tomography, carboplatin (90 mg / m2) chemotherapy and 6 x 6 Gy fraction dose radiotherapy were applied to delay the metastasis formation and local control of the mass was achieved.
Although the patient did not show any relapse during the postoperative period, he died within 3 months of multi-organ failure due to distant metastases.
Surgical approach, chemotherapy and radiotherapy provide benefits in the clinical evaluation of the patient in the treatment of oral malignant melanoma. As a result, it is predicted that further studies in determining BRAF gene mutations, which are among the targeted treatment options, will provide benefits to human and veterinary oncology.