Diffuse bronchiolo‐alveolar carcinoma in a dog

Abstract

An eight‐year‐old female German wirehaired pointer was presented with signs of respiratory distress. Clinical examination, laboratory results, thoracic radiography and echocardiography indicated the presence of a diffuse interstitial lung disease with secondary appropriate erythrocytosis, pulmonary hypertension and cor pulmonale. Transthoracic fine needle aspiration biopsy of the lung suggested malignant epithelial neoplasia. A primary lung cancer with an unusually diffuse distribution of miliary/micronodular lesions was found at postmortem examination. Histological diagnosis was bronchiolo‐alveolar carcinoma. Bronchiolo‐alveolar carcinoma can occasionally occur in a diffuse fashion involving most or all of the lung parenchyma. In man, diffuse bronchiolo‐alveolar carcinoma is considered a great imitator of other, more common diffuse interstitial forms of lung disease. This case report indicates that it is also a differential diagnosis to consider in dogs.

Carcinoma bronquíolo-alveolar difuso em um cão: aspectos clínico-patológicos e imuno-histoquímicos

“…São divididos em tumores de origem epitelial ou mesenquimal e classificados de acordo com o local de origem (broncogênico, glândula bronquial, ou bronquíolo-alveolar), com o padrão histológico (adenoide, escamoso, grandes células, pequenas células), ou uma combinação destes (WILSON & DUNGWORTH, 2002 ao longo dos alvéolos pulmonares e junções bronquíolo-alveolares pré-existentes, geralmente ocorrem como nódulos isolados ou na forma de múltiplas massas na periferia do pulmão (WILSON & DUNGWORTH, 2002). A forma difusa do CBA é rara tanto em humanos quanto em animais, pode envolver grande parte ou todo o parênquima pulmonar induzindo ao diagnóstico de pneumonia na avaliação clínica e radiográfica (LUDINGTON et al, 1972;BERTAZZOLO et al, 2002). Histologicamente, neoplasmas primários de pulmão podem ser confundidos com metástases pulmonares de outras formas de câncer.…”

“…Em humanos e animais, tumores pulmonares difusos são comumente confundidos com pneumonia difusa (LUDINGTON et al, 1972;BERTAZZOLO et al, 2002). O diagnóstico definitivo nesses casos deve ser feito pelo exame histológico de material obtido por método de biópsia ou necropsia.…”

Canine Diffuse Lepidic Predominant Adenocarcinoma

“…Most of the reported cases of lepidic predominant adenocarcinoma in dogs have a single peripheral pulmonary nodule [6,11]. The diffuse form is less common and compromises a large part of the pulmonary parenchyma, and could be mistaken by pneumonia in the clinical and radiographic evaluation [2,6]. In the reported case, despite the presence of a single nodule in the right cranial lobe of the lung, there was also a generalized involvement of the parenchyma, which made clinical diagnosis difficult.…”

Dirofilaria immitis infection in dogs: unusually located and unusual findings

“…Venco et al (2005) indicated a clinically permanent coughing, dyspnea, and weakness during the development of the disease. In this study, in addition to undernutrition at D. immitis and lung tumors cause right ventricular failure by gradually leading to pulmonary hypertension, right ventricular dilatation, and hypertrophy in dogs (Rawlings and Lewis 1977;Soulsby 1982;Bertazzolo et al 2002;Wang et al 2005). The main differentiations observed in the right ventricular hypertrophy on the ECG are right axis deviation (>100°), deep S waves in I, II, and III, aVF, and V3, positive T waves in S v3 >0.8 mV, and V 10 (Atkins et al 1995), which should be accepted as criteria.…”