A case of adenocarcinoma of the endometrium extending into the leiomyoma of the uterus in a rabbit

Metastatic Uterine Adenocarcinoma in a Sable Antelope (Hippotragus niger)

Simple Summary

A female sable antelope with a history of gradual loss of body condition was found dead by the owner. Macroscopic examination revealed an enlarged spleen and liver that were covered in white-to-cream-coloured nodules. The uterus also showed a few small, white-to-cream-coloured nodules, with similar nodules present in other parts of the body. Microscopic analysis of sections of the uterus revealed tumour cells with an appearance that was similar those seen in sections of the other tissues. Critically, tumour cells were seen in the lymphatics within the lungs. The tumour cells in the uterus showed positive staining for cytokeratin as did the tumour cells in the sections of other tissues, confirming they were of epithelial origin. In addition, electron microscopy of the uterus and liver showed tumour cells arranged in groups with junctions present between the cells. This confirmed that the tumour cells seen in the liver were the same as those seen in the uterus and were of epithelial origin. Thus, a diagnosis was made of uterine adenocarcinoma with widespread metastasis. This is the first report of uterine adenocarcinoma in a sable antelope.

Abstract

A nine-year-old intact female sable antelope (Hippotragus niger) with a six-week history of gradual loss of body condition was found dead by the owner and presented for autopsy. Macroscopic examination revealed an enlarged spleen and liver with the hepatic and splenic parenchyma showing extensive infiltration with firm, white to cream-coloured nodules. The uterus showed a few small, firm, well-demarcated, white-to-cream-coloured nodules in the uterine body. Similar nodules were present in the mediastinum, parietal pleura, heart, and marrow cavity of the femur. Histological analysis of the uterus revealed densely cellular neoplastic proliferations, forming nests, tubules, and acini within an abundant fibrovascular stroma. The samples from the other tissues revealed neoplastic cells with a similar appearance to those seen in the uterus, also forming nests and acini in a fibrovascular stroma. Importantly, multiple neoplastic cells were also seen in the peribronchiolar lymphatic vessels. The neoplastic cells in the uterine sections showed positive immunohistochemical labelling for cytokeratin, as did the neoplastic cells in the sections of liver and parietal pleura, confirming they were of epithelial origin. In addition, transmission electron microscopy of the uterus and liver showed neoplastic cells arranged in groups surrounded by basement membranes and interspersed with collagen fibres. Junctions were present between the cells, and junctional complexes could be seen at some cell surfaces. This confirmed that the neoplastic cells seen in the liver sample were the same as those seen in the uterine sample and were of epithelial origin. Thus, a diagnosis was made of uterine adenocarcinoma with widespread metastasis. This is the first report of uterine adenocarcinoma in a sable antelope.

Assessment of reported uterine lesions diagnosed histologically after ovariohysterectomy in 1,928 pet rabbits (Oryctolagus cuniculus)

OBJECTIVE

To assess variations in age, breed, and clinical signs in rabbits with neoplastic or nonneoplastic uterine lesions and to investigate potential relationships between endometrial adenocarcinoma and age at ovariohysterectomy or breed in rabbits.

ANIMALS

1,928 rabbits that underwent ovariohysterectomy for treatment or prevention of possible uterine disease.

PROCEDURES

With an online questionnaire distributed to 441 veterinary hospital members of the Japanese Society of Exotic Pet Medicine, data were retrospectively collected regarding age, breed, and findings on physical and histologic examinations for pet rabbits that underwent ovariohysterectomy between January 1, 2009, and April 30, 2018. Rabbits were grouped by reported age, breed, clinical signs, and uterine lesions, and results were assessed across groups. Logistic regression analysis was used to identify potential relationships between endometrial adenocarcinoma and breed or age at ovariohysterectomy in rabbits.

RESULTS

The questionnaire response rate was 9.8% (43/441), with data reported for 1,928 rabbits (mixed breed, 600 [31.1%]; Netherland Dwarf, 520 [27.0%]; Holland Lop, 286 [14.8%]; or various other breeds, 522 [27.1%]). The most commonly reported neoplastic and nonneoplastic lesions were endometrial adenocarcinoma (1,035/1,928 [53.7%]) and endometrial hyperplasia (842 [43.7%]), respectively, and the most commonly reported clinical sign was hematuria or serosanguineous vaginal discharge (1,020/1,928 [52.9%]). As age at ovariohysterectomy increased, so did the odds (OR, 1.826; 95% CI, 1.640 to 2.033) of uterine adenocarcinoma.

CONCLUSIONS AND CLINICAL RELEVANCE

Results supported ovariohysterectomy in rabbits before 2 years of age as a key preventative measure to mitigate uterine disease, particularly endometrial adenocarcinoma.

Endometrioid Adenocarcinoma Arising in Adenomyoma in a Woman with a Genital Prolapse - Case Report

BACKGROUND:

Endometrial cancer is the third-ranked genital malignancy in women and includes 3% of cancer deaths. There is a 2.8% chance of a woman developing endometrial cancer during her lifetime. Low-grade endometrioid adenocarcinomas are often seen along with endometrial hyperplasia, but high-grade endometrioid adenocarcinomas have more solid sheets of less-differentiated tumour cells, which are no longer organised into glands, often associated with surrounded atrophic endometrium.

CASE REPORT:

We present an unusual case of endometrial adenocarcinoma arising in adenomyoma in 74-year old woman presented with genital prolapse, without other clinical symptoms. Ultrasound evaluation revealed endometrium with 4 mm-thickness and atrophic ovaries. The cervical smear was normal. The patient underwent a total vaginal hysterectomy. The histopathology of the anterior uterine wall revealed an intramural adenomyoma of 4 mm in which some endometrial glands with malignant transformation of well-differentiated endometrioid adenocarcinoma without infiltration in surrounding myometrium and lymphovascular invasion were present. The endometrium lining the uterine cavity was predominantly atrophic, and only one focus of simplex and complex hyperplasia was found, with cell-atypia. According to AJCC/FIGO 2010, the tumour was classified: pTNM = pT1B pNX pMX G1 R0 L0 V0 NG1, Stage I. On dismiss, the near-future oncological consultation was recommended.

CONCLUSION:

We would like to point out the rare occurrence of such type of malignancy and the importance of meticulous histopathology evaluation, even after reconstructive surgery for genital prolapse.

Uterine disorders in 50 pet rabbits

Although the incidence of uterine disorders in pet rabbits is high there are only a few retrospective studies and case reports on genital tract disease in female rabbits. Uterine disorders were assessed in 50 pet rabbits. In 31 pet rabbits with suspected clinical uterine disease, medical records were further reviewed regarding clinical signs, diagnostic workup, treatment as well as the outcome itself. Uterine adenocarcinoma (54%) was most frequently diagnosed, followed by endometrial hyperplasia (26%). Serosanguineous vaginal discharge was the predominant clinical sign observed by the rabbit owners. In approximately 50% of the rabbits with suspected uterine disorders, abdominal palpation revealed enlarged and/or irregular masses in the caudoventral abdomen indicating uterine lesions. Out of 23 rabbits undergoing ovariohysterectomy, four were either euthanized or died shortly after surgery because they were clinically unstable. Overall, 80% of the ovariohysterectomized animals were still alive 6 mo after surgery. In female pet rabbits that are not breeding, either ovariohysterectomy should be performed at an early age or routine checks including ultrasonography of the abdomen are recommended on a regular basis.