Malignant mixed tumor in the salivary gland of a cat

Pathological and immunohistochemical characterization of pancreatic carcinoma in cats

The aim of this study was to characterize the pathological and immunohistochemical aspects of pancreatic carcinoma in cats, through a retrospective study. From January 2010 to December 2021, 1,908 cat necropsies were performed, in which 20 cases of exocrine pancreatic neoplasia were diagnosed (1.04%). Affected cats were mature adults and seniors, except for one 1-year-old cat. In 11 cases the neoplasm was a soft, focal nodule on the left (8/11) or right (3/11) lobe. In nine cases there were multifocal nodules throughout the pancreatic parenchyma. The size of the single masses ranged from 2 to 12 cm, and the multifocal masses from 0.5 to 2 cm. The most frequent tumour type was acinar carcinoma (11/20), followed by ductal carcinoma (8/20), undifferentiated carcinoma (1/20) and carcinosarcoma (1/20). On immunohistochemical evaluation, all the neoplasms were remarkably reactive to pancytokeratin antibody. The ductal carcinomas were strongly reactive for cytokeratins 7 and 20, which proved to be a good marker for pancreatic ductal carcinoma in cats. The main form of metastasis was abdominal carcinomatosis, with a marked invasion of blood and lymphatic vessels by neoplastic cells. Our findings reinforce the fact that pancreatic carcinoma should be rated highly in the differential diagnosis in mature adult and senior cats with abdominal masses, ascites and/or jaundice.

Bilateral Thyroid Carcinosarcoma in a Cat

A neutered female domestic shorthaired cat was presented for a rapidly growing left cervical mass and a 6-month history of primary hyperthyroidism. Cytological examination of the mass was consistent with a sarcoma. Due to poor clinical response the cat was humanely destroyed and a post-mortem examination was performed. This revealed a markedly enlarged, irregularly shaped left thyroid gland with signs of infiltration of the trachea. The contralateral (right) thyroid was also moderately enlarged and irregularly shaped. Histopathological examination of the cervical masses indicated bilateral thyroid carcinosarcomas, evidenced by positive immunohistochemical labelling for vimentin, pan-cytokeratin and thyroid transcription factor-1 of the appropriate cell populations. The cat also had a concurrent pulmonary adenocarcinoma (papillary-lepidic type), unrelated to the thyroid neoplasm. Thyroid carcinosarcoma is an uncommonly recorded canine and human neoplasm and this is the first case of this entity to be reported in a cat.

Uterine carcinosarcoma (malignant mixed Müllerian tumor): case report in a goat and literature review

Carcinosarcomas are biphasic malignant tumors composed of 2 distinct neoplastic cell populations, epithelial cells and mesenchymal cells. A 13-y-old, female, mixed-breed goat was presented with a 1-wk history of anuria and lethargy. Transabdominal ultrasonography showed an irregular and heterogeneous structure in the region of the bladder and uterus and changes in the echogenicity of both kidneys. Given the poor prognosis, euthanasia was elected. Autopsy revealed a large mass within the uterine cervix and confirmed the changes in the urinary tract. Histopathology and immunohistochemistry revealed a mixed, anti-cytokeratin AE1/AE3-positive epithelial, and vimentin-positive mesenchymal neoplasm consistent with a homologous carcinosarcoma, also called malignant mixed Müllerian tumor, with areas of double-labeling. We highlight the complexity of the diagnosis of uterine neoplasms in domestic animals and in goats in particular.

[Magnetic resonance imaging anatomy of the feline salivary glands]

OBJECTIVE

The aim of the study was to define anatomical characteristics of feline salivary glands using magnetic resonance imaging (MRI) and to describe landmarks for their reliable identification.

MATERIAL AND METHODS

Heads of 37 adult cats without signs of diseased salivary glands on clinical examination or history were examined. In cats included in the prospective part of the study, the MRI study was completed within one hour after euthanasia (n = 16). In the retrospective part, previously performed MRI studies were evaluated (n = 21). The prospective part of the study included the following standardized sequences: T2-weighted (T2W) turbo spin echo (TSE), T2W fat-suppressed TSE and proton density weighted (PDW) TSE images in a transverse plane as well as T1-weighted (T1W) fast field echo (FFE) in the transverse, sagittal and dorsal planes. In the retrospective part, T2W TSE and T1W TSE transverse images pre- and post-contrast were analyzed. Initially, identification and delineation of the salivary glands from surrounding tissue was assessed. Anatomical structures of the head were then identified and defined as landmarks. The dimensions of the glands were measured on T2W TSE images and the signal intensity in relation to that of fat and muscle was described using all sequences.

RESULTS

In total, 95.9% of the parotid glands and 100% of the mandibular glands could be visualized on T1W TSE and FFE images and on T2W TSE images. Additionally, 93.3% of the zygomatic glands were identified on T2W TSE sequences and 82.5% on T1W TSE and FFE images. The ventral buccal glands could be demarcated in some sequences (T2W TSE: 51.4%, T1W TSE and FFE: 18.9%). Anatomical landmarks facilitated gland identification. Comparing the size of the salivary glands of both groups revealed differences of up to 2 mm.

CONCLUSION

Both the large salivary glands (Glandula [Gl.]. parotis and Gl. mandibularis) and the small salivary glands (Gl. zygomatica and Gl. buccalis ventralis) of the cat can be reliably identified on MRI images.

[Computed tomographic anatomy of the salivary glands in the cat]

OBJECTIVE

The aim of the study was to define anatomical characteristics of the feline salivary glands in cross-sectional images obtained by unenhanced computed tomography (CT) and to describe landmarks for a reliable identification.

MATERIAL AND METHODS

Heads of adult normocephalic cats without indications of cephalic disease were examined. Cats were included in the prospective part of the study when examined no later than 1 hour post mortem (n = 16). In the retrospective part of the study, previous CT-studies were evaluated (n = 25). The results of both groups were evaluated separately. Initially, the possibility of identifying and delineating the salivary glands from the surrounding tissue was assessed. Anatomical structures of the head were then defined as landmarks. Dimensions and density (Hounsfield units, HU) of the salivary glands were determined based on transversal and reconstructed sagittal images.

RESULTS

In total, 94.3% of the parotid glands, 90.7% of the mandibular glands and 96.8% of the zygomatic glands could be delineated. The remaining salivary glands could not be identified. Anatomical landmarks, including the external ear canal, the musculus (M.) masseter, the M. pterygoideus medialis and the bulbus oculi facilitated the identification. Comparing the size of the salivary glands of both groups revealed differences (measured lateromedially and rostrocaudally) in size of ≤   2 mm. The definable salivary glands varied significantly in their density. The mean density of the glandula (Gl.) parotis was 65 HU, of the Gl. mandibularis 62 HU and of the Gl. zygomatica 57 HU. The comparisons of densities of both sides of the glands did not show statistically significant differences.

CONCLUSIONS

The large salivary glands (Gl. parotis and Gl. mandibularis) and the Gl. zygomatica of the cat can be reliably identified in CT-images. CT landmarks and data regarding the size and density of each gland could be gathered. The remaining minor salivary glands could not be delineated accurately. The difference in depicting the glands can be explained mainly by a lack of contrast with the surrounding tissue.

Carcinosarcoma of the biliary system in a cat

A 12-year-old, mixed-breed domestic cat was diagnosed with a multicystic hepatic mass via ultrasonographic examination and computer tomography scan. The tumor associated with the left medial liver lobe, and connected by a thin stalk to the hilar region, was surgically removed. The mass was firm, encapsulated, mottled white to red black, multinodular, and cystic. Histologic diagnosis was carcinosarcoma supported by positive immunohistochemistry for cytokeratins and vimentin of atypical neoplastic cell populations. On the basis of morphology, the origin was considered to be in the biliary tract. Biliary carcinosarcoma is a rare neoplasm that occurs in people. The epidemiology and risk factors have not yet been determined, and the prognosis is poor except for cases in which curative resection is performed.

Pancreatic carcinosarcoma in a cat

A 10-year-old female American shorthair cat was presented for evaluation of weight loss. An intra-abdominal mass was found on ultrasonography and laparotomy was performed. The mass was located in the left uterine horn and further masses were found in the pancreas, greater omentum and diaphragm. Microscopical examination revealed that the pancreatic mass had epithelial and mesenchymal components, which on immunohistochemistry expressed cytokeratin and vimentin, respectively. In addition, some spindle cells expressed vimentin and E-cadherin, which might suggest epithelial to mesenchymal transition. In contrast, the uterine, omental and diaphragmatic masses had only mesenchymal composition. The pancreatic lesion is proposed to be a primary carcinosarcoma with metastasis of only the mesenchymal component to distant sites. This the first report of pancreatic carcinosarcoma in a cat.