Prevalência e achados epidemiológicos, anatomopatológicos e imuno-histoquímicos dos tumores hepáticos malignos primários de cães da Região Central do Rio Grande do Sul (1965-2012)

Abstract

A prevalência e os aspectos epidemiológicos, anatomopatológicos e imuno-histoquímicos dos tumores hepáticos malignos primários (THMP) em cães foram estudados. De 7.373 cães necropsiados em 48 anos (1965-2012), 64 morreram de THMP, o que corresponde a 0,9% do total de cães que morreram por qualquer causa, 7,8% do total de cães que morreram por tumores em geral e 33,5% do total de cães que morreram por tumores hepáticos. Desses 64 casos de THMP, 51 foram revistos histologicamente, avaliados imuno-histoquimicamente e reclassificados como carcinomas (colangiocarcinomas [n=36], carcinomas hepatocelulares [n=9] e hepatocolangiocarcinoma [n=1]) e sarcomas (hemangiossarcomas [n=5]). Dos cães com colangiocarcinomas e carcinomas hepatocelulares em que a idade estava disponível nos protocolos, 64,7% e 77,8% eram idosos, respectivamente. Na necropsia, colangiocarcinomas caracterizaram-se principalmente por ocorrerem em um padrão multinodular (83,3%), enquanto carcinomas hepatocelulares ocorreram tanto de forma massiva (44,4%) quanto nodular (44,4%). Metástases extra-hepáticas foram vistas em 77,8% e 33,3% dos casos de colangiocarcinomas e carcinomas hepatocelulares, respectivamente, e em relação aos colangiocarcinomas afetaram principalmente pulmões (52,8%), linfonodos (50%) e peritônio (19,4%). Ascite (22,2%) e icterícia (22,2%) foram achados associados ocasionalmente com ambos os tumores. Na histologia, a maior parte dos colangiocarcinomas (86,1%) e dos carcinomas hepatocelulares (55,6%) tinha padrão tubular e trabecular, respectivamente. Na imuno-histoquímica, a maioria (63,9%) dos colangiocarcinomas demonstrou imunomarcação para CK7 e nenhum imunomarcou para Hep Par 1. A maioria (55,6%) dos carcinomas hepatocelulares demonstrou imunomarcação para Hep Par 1 e nenhum imunomarcou para CK7. Os resultados aqui apresentados demonstram uma altíssima prevalência de THMP, principalmente colangiocarcinomas, e servem para auxiliar, através dos achados de necropsia, histologia e imuno-histoquímica, patologistas veterinários no diagnóstico dessa tão comum forma de câncer em cães da Região Central do RS, Brasil.

Primary hepatic neoplasms in cattle

“…All cattle affected in this study were adults, aged three years or older, similar to that reported by other authors (Anderson & Sandinson 1968, Wettimuny 1969, Braun et al 2005, Jeong et al 2005. Females were more affected than males, and, although few studies assessed a possible sex predilection for the development of liver tumors in cattle (Wettimuny 1969, Braun et al 2005, in dogs and cats it is known that there is no such predisposition (Patnaik et al 1981, Trigo et al 1982, Lawrence et al 1994, Liptak et al 2004, Flores et al 2013, Van Sprundel et al 2014. Probably females were overrepresented in this study since these are slaughtered later, and are thus, in the so-called "cancer age", as previously postulated (Reis et al 2017).…”

Pathological and immunohistochemical aspects of primary hepatobiliary neoplasms in cats

“…In the present study, the multinodular pattern was identified in 60% of cholangiocarcinomas, corroborating the literature, which describes this as the most common gross presentation in dogs and cats (Patnaik 1992, Cullen & Stalker 2016. In a survey with dogs, 83% of the cases were multinodular (Flores et al 2013). In the present study, 20% of cholangiocarcinomas were classified as of massive pattern, and were characterized by large masses that obliterated the entire hepatic lobe (Cullen 2017).…”

“…In the present study, 20% of cholangiocarcinomas were classified as of massive pattern, and were characterized by large masses that obliterated the entire hepatic lobe (Cullen 2017). In dogs, this presentation has been identified in approximately 17% of bile duct neoplasms (Flores et al 2013). It is not yet clear whether multiple nodules result from intrahepatic metastases or primary lesions in different foci (Barros 2016, Cullen & Stalker 2016.…”

“…Generally, when the neoplasm is friable, there is rupture with consequent hemoperitoneum, anemia, and sudden death (Barros 2016, Cullen & Stalker 2016, Cullen 2017. Hemoperitoneum, ascites, and jaundice have been frequently reported in dogs with PHN (Flores et al 2013).…”

“…Hepatocellular carcinoma usually has three microscopic patterns: trabecular, adenoid and solid (Head et al 2003, Barros 2016). According to Cullen (2017), the solid pattern is poorly differentiated and characterized by pleomorphic cells (Crawford & Liu 2010, Flores et al 2013. Vacuolization in the cytoplasm of neoplastic hepatocytes is a frequent finding, and is associated with glycogen or lipid deposition (Cullen 2017).…”