History
A 9-year-old female domestic shorthair cat was evaluated for progressive hyporexia, lethargy, weight loss, and intermittent vomiting and regurgitation of 2 weeks' duration. The cat's vaccination status was adequate, and there was no history of notable medical illnesses or travel outside of the state of New York. Results of physical examination indicated that the cat was approximately 7% dehydrated and had a moderate amount of dental tartar. A gallop rhythm was detected during auscultation of the thorax. Abnormalities detected on CBC and serum biochemical analyses included a relative erythrocytosis and moderately high serum creatine kinase activity, respectively. Survey radiographs of the thorax were obtained (Figure 1).
Determine whether additional imaging studies are required, or make your diagnosis from Figure 1—then turn the page
Lateral (A) and ventrodorsal (B) radiographic views of the thorax of a 9-year-old cat evaluated for hyporexia, lethargy, weight loss, and intermittent vomiting and regurgitation of 2 weeks' duration.
Citation: Journal of the American Veterinary Medical Association 228, 9; 10.2460/javma.228.9.1341
Radiographic Findings and Interpretation
A poorly defined soft tissue mass effect is evident in the caudal aspect of the thorax (Figure 2). A diffuse bronchial pattern can also be seen. A soft tissue opacity in the caudodorsal portion of the thorax may be associated with the esophagus, mediastinum, lungs, cardiovascular structures, diaphragm, or hypaxial muscles.
Same ventrodorsal radiographic view as in Figure 1. Notice the poorly defined soft tissue opacity (arrows).
Citation: Journal of the American Veterinary Medical Association 228, 9; 10.2460/javma.228.9.1341
Comments
On the basis of clinical signs, history, and radiographic findings, an esophageal stricture was suspected, and a positive contrast esophagram was performed. Liquid barium sulfate suspension (5 mL, PO) was administered to the cat, and orthogonal radiographic views were obtained 10 minutes and 45 minutes after barium sulfate administration. Compression of the distal portion of the esophagus with minimal flow of contrast medium into the gastric lumen was detected (Figure 3). A mass was suspected as the cause of the compression, and esophagoscopy was performed. Esophagoscopy revealed approximately 95% of the esophageal lumen was compressed by an extraluminal or transmural mass in the distal third of the esophagus (Figure 4). The mucosa was erythematous and mildly ulcerated in the region of the compression, and biopsy was not successful.
Right lateral positive contrast esophagram of the cat in Figure 1. Notice distal compression of the esophagus (white arrow) and segmental esophageal dilation (gray arrows) with minimal flow of contrast medium from the esophagus into the gastric lumen (black arrows).
Citation: Journal of the American Veterinary Medical Association 228, 9; 10.2460/javma.228.9.1341
Esophagoscopic view of the distal portion of the esophagus of the cat in Figure 1. Notice marked compression of the esophageal lumen (outlined white arrow) and mucosal erythema (white arrows). A small volume of residual contrast medium can be seen on the mucosa of the dependent portion of the esophagus (black arrow).
Citation: Journal of the American Veterinary Medical Association 228, 9; 10.2460/javma.228.9.1341
The owner chose to have the cat euthanatized. Necropsy revealed the distal third of the esophagus was circumferentially and transmurally thick, and adhesions to thoracic vertebral bodies, the diaphragm, and the left caudal lung lobe were detected. Histologic examination revealed bronchial gland carcinoma with metastasis to the distal portion of the esophagus, diaphragm, and thoracic portion of the vertebral column.
Primary lung tumors in cats are rare; the incidence of primary lung tumors in cats in 1 study1 was 0.38%. No breed or sex predisposition has been detected; the mean age of cats at the time of diagnosis is 11 years (range, 5 to 15 years).2 Primary lung tumors are commonly classified as adenocarcinomas, squamous cell carcinomas, bronchioloalveolar carcinomas, anaplastic carcinomas, adenomas, and sarcomas. The most frequently diagnosed histologic tumor type in cats is adenocarcinoma.1
Clinical signs of primary lung tumors in cats most often include lethargy, dyspnea, and weight loss.3 Metastasis is common and may develop in regional lymph nodes, local tissues, and extrathoracic sites.2–5
- 1↑
Miles KG. A review of primary lung tumors in the dog and cat. Vet Radiol Ultrasound 1988;29:122–128.
- 2↑
Barr F, Gruffydd-Jones TJ, Brown PJ, et al. Primary lung tumors in cats. J Small Anim Pract 1987;28:1115–1125.
- 3↑
Hahn KA, McEntee MF. Primary lung tumors in cats: 86 cases (1979–1994). J Am Vet Med Assoc 1997;211:1257–1260.
- 4
Forrest LJ, Graybush CA. Radiographic patterns of pulmonary metastasis in 25 cats. Vet Radiol Ultrasound 1998;39:4–8.
- 5
Meyer A, Hauser B. Lung tumor with unusual metastasis in a cat—a case report. Schweiz Arch Tierheilkd 1995;137:54–57.
