Epidermoid lung carcinoma of the dog compared to smoker's carcinoma in man
Stunzi, H.
Schweizer Archiv für Tierheilkunde 113(6): 311-319
1971
ISSN/ISBN: 0036-7281 PMID: 5107059 Document Number: 32450
Among 7,350 dogs examined P.M. in Zurich between 1952 and 1970, 84 cases of primary lung carcinoma (and 962 other tumours) were found. Of these, 70 were adenocarcinomata, 5 anaplastic and 5 epidermoid (plate-epithelial) forms, and 4 carcinoid or unclassifiable. The epidermoid forms all occurred in old dogs (9, 13 or 15 years) that had shown coughing, dyspnoea and progressive weakening as clinical signs. The typical histological picture of nodules of plate-epithelial cells separated by fibrous bundles was seen in all lungs, except that in one case these formed epidermoid islands and were surrounded by areas of anaplastic small-cellular carcinoma. There was no keratinization in four cases. The tumours mostly originated from the bronchial epithelium, but in one case cancerous degeneration and keratinization of the bronchial glands suggested that the latter were the starting points. Metastasis to peribronchial lymphatic vessels and nodes was frequent. The relatively much lower incidence of canine epidermoid and anaplastic lung tumours than of the clinically, histologically and patho-genetically very similar human forms, despite increasing atmospheric pollution, and the difficulty in inducing these carcinomata in dogs by means of forced cigarette smoking indicate that some exogenous carcinogenic factor acting on human beings is not effective on dogs.