Fine Needle Aspiration Cytology in the Diagnosis of Canine Cutaneous Transmissible Venereal Tumor— Case Report

Abstract

Fine needle aspiration cytology (FNAC) has been widely used in the diagnosis of lesions from various origins, especially neoplastic. The technique is simple, fast, safe, minimally invasive and inexpensive, which allows through the evaluation of cell morphology to establish prognosis, delineate surgical margins, monitor lesion growth, validate indication euthanasia during surgery and monitor chemotherapy protocols. Diagnosis of canine transmissible venereal tumor (TVT) can be accomplished with ease and precision, even to be rated, according to the degree of aggressiveness. The study objective was to demonstrate the effectiveness of the examination in the diagnosis of TVT plasmacytoid type. An eight-month dog presented to the veterinary hospital (HV), faculty of veterinary medicine and animal science, FMVZ, UNESP-Univ Estadual Paulista with clinical suspicion of cutaneous lymphoma. By presenting multiple nodular lesions, FNAC was performed to cytological diagnosis. The tissue showed cells consistent with TVT. The animal was treated, and a total cure was achieved. According to the literature, TVT mainly affects external genitalia of sexually active animals and its transmission is more frequent during intercourse. In addition, animals sexually immature and without contact to the street dogs, hardly have injuries by TVT. In this case, verrucous and ulcerated lesions on the vulva of its mother during pregnancy and childbirth infected the animal. Diffuse and predominant dorsal injuries occurred due to both exfoliation of breast tumor during delivery and immunosuppression of pup at birth, thus favoring an atypical transmission.

Isolated cutaneous transmissible venereal tumour in dogs

“…The implantation of viable neoplastic cells in scarified tissue is the most accepted form of natural transmission, and thus, it is believed that TVT cannot be transmitted to an intact epithelium. 16 The TVT is mainly transmitted by coitus. 5 Copulation movements can generate excoriations in the genital mucosa of males and females, making both susceptible to the implantation of tumour cells.…”

Tumor venéreo transmissível canino com resistência quimioterápica e metástase esplênica - Relato de caso

“…No caso aqui em discussão, segundo o relato do tutor, a cadela escapou para as ruas no período de cio antes de apresentar os sintomas da doença. A transmissão do TVTC ocorre por contato direto de um cão doente com outro sadio pelo coito, lambedura, farejo e mordedura (Rocha et al 2014), sendo que a célula tumoral se propaga naturalmente entre os indivíduos como uma linhagem celular contagiosa (Strakova y Murchison 2015). O coito é o principal modo de transmissão e nesse caso, a genitália é o local mais comumente afetado (Ganguly et al 2016;Strakova y Murchison 2014).…”

“…O Tumor Venéreo Transmissível Canino (TVTC) integra um pequeno e fascinante grupo de canceres transmissíveis conhecidos na natureza (Metzger et al 2016). Propaga-se naturalmente entre os cães pela transferência alogênica de células tumorais durante o coito (Ganguly et al 2016;Murgia et al 2006;Strakova y Murchison 2014), podendo ainda ser encontrado em ocorrência extragenital devido aos hábitos sociais de interação canina, como cheirar, lamber, arranhar e morder (Rocha et al 2014).…”

Plasmocitoma extramedular em bulbo peniano de cão: relato de caso

“…The TVT may still be subdivided by cytological analysis in two different ways: linfocitoide (round morphology, scant cytoplasm and rounded nucleus) and plasmacytoid (this appears as an ovoid morphology, abundant cytoplasm, eccentric nucleus and a larger number of vacuoles), being that the venereal tumors with lesser vacuoles, especially linfocitoide are differential diagnosis of other round cell neoplasms, including plasmacytomas, as well as the plasmacytoid with scarce vacuolization that can be confused with other round cell tumors such as plasmacytoma (Flores et al, 2012;Rocha et al, 2014), which can hinder the diagnosis in a cytological preparation of which characteristics are not as well differentiated as in the cytological examination of the animal in question.…”