Endometrial Disease in Six Cats with Clinical and Histopathological Features Resembling Atypical Endometrial Hyperplasia in Humans.

In humans, atypical endometrial hyperplasia (AEH) is considered as a precancerous lesion of endometrial adenocarcinoma (EA), from which it must be distinguished. Precancerous lesions have not been reported in cats with EA. We now document the histopathological features of endometrial lesions in six cats, which histopathologically resembled human AEH and had a good prognosis following ovariohysterectomy. Grossly, one cat presented with papillomatous nodules and three cats had pyometra. Histopathologically, proliferation of endometrial epithelial cells without atypia was observed in all cases. In some regions of the endometrium, cells had increased atypia and were arranged in stratified layers, which formed irregular ducts and papillary structures. No invasive behaviour or vascular invasion was observed. On the basis of these findings, the cats were diagnosed with non-invasive or early-stage adenocarcinoma. Immunohistochemistry for oestrogen receptor and progesterone receptor revealed an inverse correlation with the severity of the endometrial lesions and degree of malignancy of tumour cells. Ki67 labelling revealed that mitotic activity increased as the lesion developed. All cats survived, with a median survival time of 385 days (range: 229-744 days). The distribution of the histopathological endometrial changes and the non-invasive behaviour in these feline cases resemble cases of AEH in humans.

Evaluation of transcervical insemination using frozen semen by flexible endoscope in dogs.

We evaluated transcervical insemination (TCI) using frozen semen by flexible endoscopy in dogs. Eight female and eight male beagles were used in this study. A flexible endoscope and a washing tube were used for TCI. A tracheal tube was used as an alternative to the penis and was an auxiliary for inserting the flexible endoscope. The mean time required to insert the washing tube into the external os of the uterus after inserting the endoscope into the tracheal tube was 7.5 min. Slight or mild pain was observed in all bitches during TCI. However, TCI could be easily performed with retention in all bitches and without sedation anesthesia. The tracheal tube was useful to ensure the visual field using air sufflation. Clinical signs suspicious of infection were not observed in any bitches from the TCI to the pregnancy diagnosis. The conception rate was 87.5%, and the mean number of fetuses was 6.3. TCI using a flexible endoscope in bitches was performed quickly with minimal invasiveness. We present a new method of TCI in dogs. This method should be studied in small and large breeds to obtain more detailed results.

The role of endoscopic ultrasound in the evaluation of rectal polypoid lesions in 25 dogs.

We investigated the role of endoscopic ultrasound in the evaluation of rectal polypoid lesions in 25 dogs. Twenty-five cases of rectal polypoid lesions in dogs who underwent surgery after endoscopic and EUS assessment were studied. The invasion depth of the polypoid lesion was classified as M stage (lesions in the mucosa only), SM stage (lesions in the mucosa and submucosa), and MP stage (lesions extending to the muscularis propria). Transabdominal ultrasound was performed in nine cases, but not all were evaluated in detail. EUS provided detailed images for all cases and showed a significant correlation with surgical pathology in the T stage (accuracy, 92%; K = 0.77). As per classification by invasion depth, inflammatory polyps were only M polypoid lesions, whereas SM and MP polypoid lesions were only adenocarcinomas (P < 0.05). The average survival time according to specific condition was as follows: 1,235 days for inflammatory polyps, and 804 days for M adenocarcinoma. The survival time of two SM adenocarcinoma cases was 756 and 2,114 days, respectively, and the survival time of two MP adenocarcinoma cases was 16 and 42 days, respectively. EUS were useful for the evaluation of rectal polypoid lesions in dogs, whereas transabdominal ultrasound was not. Determination of the invasion depth of polypoid lesions using EUS may be useful for the evaluation of malignancy and prognosis.