Hamartomatous type polyps in the rectum from a Pekinese dog

摘要

Intestinal polyps are often benign neoplasms and are occasionally encountered in dogs compared to humans. The present case reports the occurrence of rectal polyps in an old (15 year old) male Pekinese dog. Using conventional histological examinationsand specific staining (Masson's trichrome and Mayer's mucicarmine methods) and using immunohistochemistry with anticytokeratin, a actin, desmine and vimentin as primary antibodies, it was observed that polyps were formed by epithelial cells and mesenchymal structures (goblet cells and dilated glands containing mucin deposits, proliferated capillaries and muscle cells) and may be considered as an hamartomatous type. Furthermore, because of the arborescent organisation of the muscle cells from the laminamuscularis to the lamina propria and the resultant polyp invasion, these lesions would correspond to the Peutz-Jeghers type described in human medicine. These results emphasize the interest to couple histological and immunohistochemical examinations of colorectal polyps in order to classify polyps in dog with more accuracy.