K. B. Corgozinho

Radiation therapy for feline cutaneous squamous cell carcinoma using a hypofractionated protocol

The objective of this paper was to evaluate the efficacy of a hypofractionated radiation protocol for feline facial squamous cell carcinoma (SCC). Twenty-five histologically confirmed SCCs in 15 cats were treated with four fractions of 7.6–10 Gy each, with 1 week intervals. The equipment used was a linear accelerator Clinac 2100 delivering electron beam of 4 or 6 MeV, and a bolus of 5 or 10 mm was used in all lesions. Of the lesions, 44% were staged as T4, 16% as T3, 8% as T2 and 32% as T1. Of the irradiated lesions, 40% had complete response, 12% had partial response and 48% had no response (NR) to the treatment. For T1 tumors, 62.5% had complete remission. Mean overall survival time was 224 days. Owners requested euthanasia of cats having NR to the treatment. Mean disease free time was 271 days. Side effects observed were skin erythema, epilation, ulceration and conjunctivitis, which were graded according to Veterinary Radiation Therapy Oncology Group (VRTOG) toxicity criteria. Response rates found in this study (52%) were lower when compared to other protocols, probably due to technique differences, such as fractionation schedule, bolus thickness and energy penetration depth. However, the hypofractionated radiation protocol was considered safe for feline facial SCC. Modifications of this protocol are being planned with the objective of improving the cure rates in the future.

Recurrent pulmonary edema secondary to elongated soft palate in a cat.

A 9-month-old intact female Persian cat presented with recurrent pulmonary edema secondary to an elongated soft palate. Endoscopic evaluation of the pharynx and larynx showed that the elongated soft palate was overlying the epiglottis. Partial resection of the soft palate was performed and the cat showed no further respiratory signs. This report is the first description of elongated soft palate causing airway obstruction in a brachycephalic cat.

A utilização da radioterapia no tratamento do carcinoma de células escamosas cutâneo felino avançado

Avaliou-se a eficacia da radioterapia no tratamento de felinos portadores de carcinoma de celulas escamosas cutâneo avancado. Um protocolo de fracionamento padrao de radioterapia foi aplicado em seis gatos portadores de uma ou mais lesoes cutâneas de carcinoma de celulas escamosas, em um total de sete lesoes neoplasicas, confirmadas por meio de analise histologica. Uma lesao foi classificada como T2 e seis como T4, segundo o sistema de estadiamento da Organizacao Mundial de Saude para tumores epidermais de felinos. Os animais foram submetidos a doze fracoes radioterapicas de 4 Gy, realizadas tres vezes por semana, utilizando-se um equipamento de ortovoltagem. Utilizaram-se energia de 120 Kv, 15mA e filtro 2mm de aluminio, o cone usado foi de 6x8cm, e a distância foco-pele foi de 30cm. As lesoes foram acompanhadas durante todo o tratamento radioterapico e 30 e 60 dias apos o seu termino. Neste estudo, 87% das lesoes resultaram em remissao completa, e 13%, em remissao parcial. Os efeitos colaterais do tratamento radioterapico, de acordo com a tabela de criterios de toxicidade aguda da Veterinary Radiation Therapy Oncology Group, foram leves e reversiveis em todos os casos, e incluiram eritema cutâneo, epilacao e rinite. Considerou-se a radioterapia segura para felinos com carcinoma de celulas escamosas cutâneo, levando a efeitos colaterais leves, e pode representar uma boa opcao terapeutica.

Histologic evaluation of Ki-67 and cleaved caspase-3 expression in feline mammary carcinoma

Objectives The purpose of this study was to evaluate histopathologic aspects of, and the expression of Ki-67 and cleaved caspase-3 in, feline mammary carcinoma (FMC). Methods Feline mammary tumors were surgically obtained by mastectomy from 30 female cats and were fixed with formalin and embedded in paraffin wax. Four-micron sections were stained with hematoxylin and eosin for histopathologic diagnosis. Ki-67 and cleaved caspase-3 were analyzed by immunohistochemistry. Results Samples were histologically confirmed as FMC. Positive immunostaining was observed in all cancer samples for both nuclear Ki-67 and cleaved caspase-3, with a mean positive staining percentage of 27.5% and 21.2%, respectively. No statistically significant correlations between Ki-67 and cleaved caspase-3 were observed within FMC. Conclusions and relevance A high proliferation index was found in feline mammary tumors. This is the first study evaluating cleaved caspase-3 expression in FMC.

Tratamento hipofracionado de radioterapia em felinos portadores de carcinoma epidermóide facial

Avaliou-se a eficacia do protocolo radioterapico hipofracionado no tratamento de felinos portadores de carcinoma epidermoide facial. Um protocolo hipofracionado de radioterapia foi aplicado em cinco gatos portadores de um ou mais carcinomas epidermoides faciais, em um total de 10 lesoes neoplasicas, confirmadas por meio de analise histologica. Duas lesoes foram classificadas como T1, quatro como T2, duas como T3 e duas como T4. Os animais foram submetidos a quatro fracoes radioterapicas de 7,6 a 10gy, com intervalo de uma semana entre elas, utilizando-se um acelerador linear com feixe de eletrons. O acompanhamento dos animais foi realizado semanalmente durante o tratamento e aos 30 e 60 dias apos o termino da radioterapia. Neste estudo, 40% das lesoes resultaram em remissao completa, 40% em remissao parcial e 20% nao apresentaram resposta ao tratamento. A taxa de resposta encontrada nessa pesquisa foi baixa, porem o protocolo de hipofracionamento radioterapico foi seguro para gatos com carcinoma epidermoide facial e resultou em efeitos colaterais leves/moderados