Diagnosis, Prognosis, and Treatment of Canine Hemangiosarcoma: A Review Based on a Consensus Organized by the Brazilian Association of Veterinary Oncology, ABROVET.

Hemangiosarcoma is a mesenchymal neoplasm originating in the endothelial cells of blood vessels; they can be classified as non-visceral and visceral types. Non-visceral hemangiosarcomas can affect the skin, subcutaneous tissues, and muscle tissues; visceral hemangiosarcomas can affect the spleen, liver, heart, lungs, kidneys, oral cavity, bones, bladder, uterus, tongue, and retroperitoneum. Among domestic species, dogs are most affected by cutaneous HSA. Cutaneous HSA represents approximately 14% of all HSA diagnosed in this species and less than 5% of dermal tumors, according to North American studies. However, Brazilian epidemiological data demonstrate a higher prevalence, which may represent 27 to 80% of all canine HSAs and 13.9% of all skin neoplasms diagnosed in this species. Cutaneous HSA most commonly affects middle-aged to elderly dogs (between 8 and 15 years old), with no gender predisposition for either the actinic or non-actinic forms. The higher prevalence of cutaneous HSA in some canine breeds is related to lower protection from solar radiation, as low skin pigmentation and hair coverage lead to greater sun exposure. Actinic changes, such as solar dermatosis, are frequent in these patients, confirming the influence of solar radiation on the development of this neoplasm. There are multiple clinical manifestations of hemangiosarcoma in canines. The diagnostic approach and staging classification of cutaneous HSAs are similar between the different subtypes. The definitive diagnosis is obtained through histopathological analysis of incisional or excisional biopsies. Cytology can be used as a presurgical screening test; however, it has little diagnostic utility in cases of HSA because there is a high risk of blood contamination and sample hemodilution. Surgery is generally the treatment of choice for dogs with localized non-visceral HSA without evidence of metastatic disease. Recently, electrochemotherapy (ECT) has emerged as an alternative therapy for the local ablative treatment of different neoplastic types; the use of radiotherapy for the treatment of dogs with cutaneous HSA is uncommon. There is greater consensus in the literature regarding the indications for adjuvant chemotherapy in subcutaneous and muscular HSA; doxorubicin is the most frequently used antineoplastic agent for subcutaneous and muscular subtypes and can be administered alone or in combination with other drugs. Other therapies include antiangiogenic therapy, photodynamic therapy, the association of chemotherapy with the metronomic dose, targeted therapies, and natural products. The benefits of these therapies are presented and discussed. In general, the prognosis of splenic and cardiac HSA is unfavorable. As a challenging neoplasm, studies of new protocols and treatment modalities are necessary to control this aggressive disease.

Diagnosis, Prognosis and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors.

Mast cell tumors (MCTs) are hematopoietic neoplasms composed of mast cells. It is highly common in dogs and is extremely important in the veterinary oncology field. It represents the third most common tumor subtype, and is the most common malignant skin tumor in dogs, corresponding to 11% of skin cancer cases. The objective of this critical review was to present the report of the 2nd Consensus meeting on the Diagnosis, Prognosis, and Treatment of Canine Cutaneous and Subcutaneous Mast Cell Tumors, which was organized by the Brazilian Association of Veterinary Oncology (ABROVET) in August 2021. The most recent information on cutaneous and subcutaneous mast cell tumors in dogs is presented and discussed.

Squamous cell carcinoma of unknown primary origin in a dog presenting with bone metastasis.

A 10-year-old female American Pit Bull dog was diagnosed with metastatic undifferentiated carcinoma of the scapula. Immunohistochemistry showed positive immunoexpression for cytokeratins (AE1/AE3, 34BE12, CK7) and vimentin, confirming squamous cell carcinoma. No evidence of nodules was found in the complete physical examination and imaging procedures conducted. The patient was diagnosed with carcinoma of unknown primary origin. Amputation and adjuvant chemotherapy with doxorubicin and piroxicam were performed, but the patient died of respiratory failure after 737 days of diagnosis. Necropsy confirmed undifferentiated carcinoma infiltrating the lungs and kidneys, and showing the same immunoexpression as the tumor in the scapula. Amputation associated with chemotherapy extended the overall survival time of this patient.

Endoscopic approach for a laryngeal neoplasm in a dog / Abordagem endoscópica de neoplasia em laringe em um cão

Laryngeal and tracheal tumors are rare in pets; some piece of information on their disease behavior, therapy and evolution are limited. Neoplasms in this area are a diagnostic challenge. In many cases, they can be biopsied and excised using endoscopic instruments, but there is no report of this in canines. The goal of this study is to report a successful case of a laryngeal neoplasm removal through endoscopy. A head and neck radiogram revealed a mass in the laryngeal lumen protruding into the trachea. The patient then underwent an endoscopy to confirm the radiographic diagnosis and to surgically remove the tumor. The histopathological diagnosis was poorly differentiated carcinoma. The most appropriate treatment for laryngeal tumors is the resection of the submucosa or a partial laryngectomy however, partial and total laryngectomies are associated with many postoperative complications. In contrast, the endoscopic approach allows for highly magnified visualization of the lesion in situ, which facilitates the surgical removal of the mass through videosurgery. With little manipulation of the affected area, the chances of postoperative complications are reduced, leading to a more rapid recovery. .

Tumores de laringe e traqueia são raros em animais de estimação e as informações sobre o comportamento, terapia e evolução destas neoplasias são limitadas. Neoplasias nesta área são desafios diagnósticos. Em muitos casos, pode ser feita a biópsia e excisão da massa utilizando instrumentos endoscópicos, mas não existe relato deste tipo de procedimento em caninos. O objetivo deste estudo foi relatar um caso de sucesso da remoção endoscópica de um tumor de laringe. A radiografia da região cervical revelou uma massa na luz da laringe invadindo a traqueia. O paciente foi então submetido a uma endoscopia para confirmar o diagnóstico radiográfico e remover cirurgicamente o tumor. O diagnóstico histopatológico foi de carcinoma pouco diferenciado. O tratamento mais adequado para os tumores da laringe é a ressecção da submucosa ou uma laringectomia parcial, no entanto, estas estão associadas a muitas complicações pós-operatórias. Em contraste, a abordagem endoscópica permite a visualização da lesão in situ, o que facilita a remoção cirúrgica da massa através de videocirurgia. Com pouca manipulação da área afetada, as chances de complicações pós-operatórias são reduzidas, levando a uma recuperação mais rápida. .