High-grade mucoepidermoid carcinoma of the salivary gland in a bull.

Salivary gland neoplasia is uncommon in veterinary species and has rarely been reported in cattle. Adenocarcinoma, squamous cell carcinoma, and pleomorphic carcinoma have been described in the parotid gland of dairy cows. Here we describe a case of high-grade mucoepidermoid carcinoma in a bull. The bull had a chronic history of caudal mandibular soft tissue swelling. Postmortem examination revealed a 30 × 30-cm mass with a caseonecrotic center, hemorrhage and necrosis of the ipsilateral cervical musculature, osteolysis of the right paracondylar process of the skull and right horn base, pulmonary nodules, and enlarged tracheobronchial lymph nodes. Histology of the mass, lungs, and lymph nodes revealed an invasive neoplasm composed of epithelial cells arranged in nests and ductular structures supported by a spindle cell stroma, with frequent central necrosis. Immunohistochemistry revealed that epithelial cells were diffusely positive for pancytokeratin and p63 with multifocal vimentin positivity; stromal cells were diffusely positive for vimentin and α-SMA. A salivary gland mucoepidermoid carcinoma was diagnosed based on these findings. Although rare, salivary gland neoplasia should be considered a differential diagnosis for mandibular masses in cattle.

Clear cell variant mucoepidermoid carcinoma of salivary gland in a grey wolf (Canis lupus).

A 14-year-old male grey wolf (Canis lupus) with a history of severe facial swelling was submitted for necropsy. Clinical and radiological examination demonstrated an expansile neoplastic mass in the nasal and frontal sinuses. On necropsy, an amorphous neoplastic mass and extensive necrosis were observed in the nasal turbinate. Microscopic examination revealed a tumour principally composed of obvious clear tumour cells characterised by small hyperchromatic nuclei and abundant clear cytoplasm. These clear cells were positive for mucin with PAS, PAS-D reaction, and alcian blue (pH 2.5) staining, but negative for PTAH staining. Immunohistochemically, some of tumour cells were strongly positive for mesenchymal cells (vimentin), whereas they were negative for myoepithelial antigen (alpha-SMA) and cytokeratin. Based on the histopathological and immunohistochemical features, the present case was diagnosed as high-grade clear cell variant mucoepidermoid carcinoma (MEC). This is the first description of clear cell variant MEC in a wolf.

[Long-term follow-up of a multimodally managed pulmonary mucoepidermoid carcinoma in a cat]. / Langzeitstudie einer multimodalen Behandlung eines mukoepidermoiden Lungenkarzinoms bei einer Katze.

INTRODUCTION: The present case describes the treatment of a mucoepidermoid carcinoma in a 13-year-old female sterilized European domestic cat, using lung lobectomy and -accompanying mitoxantrone chemotherapy. Six, 14, 19 and 27 months after the initial treatment tomodensitometric and radiographic examinations showed no abnormalities. However, the cat had to be euthanized 27 months after the lung lobectomy due to a soft tissue sarcoma in the interscapular area.

INTRODUCTION: Ce cas décrit un carcinome mucoépidermoïde chez un chat européen femelle stérilisée de 13 ans, entité non rapportée jusqu'alors chez cette espèce, pris en charge par lobectomie pulmonaire et chimiothérapie adjuvante avec de la mitoxantrone. L'examen tomodensitométrique et les clichés radiographiques, réalisés respectivement 6 mois, 14, 19 mois, et 27 mois après la chirurgie, ne mettaient en évidence aucune anomalie. Cependant, vingt-sept mois après l'intervention chirurgicale, une euthanasie est réalisée suite à l'aggravation en quelques mois d'un sarcome des tissus mous en région inter-scapulaire.

Mucoepidermoid Carcinoma in the Skull of an Orange-winged Amazon Parrot (Amazona amazonica).

A 33-year-old female intact orange-winged Amazon parrot (Amazona amazonica) presented for a slowly growing mass over the right eye. A computed tomography scan performed with and without intravenous contrast revealed a heterogeneous mixed soft tissue and mineral-dense mass with a small area of non-contrast-enhancing fluid density located between the orbits at the caudal aspect of the nasal passages, with associated lysis of the right caudal nasal passage and the right frontal bone. Following euthanasia, the mass was found to consist of soft tissue between the right eye and nostril over the right frontal bone. Lysis of the underlying bone resulted in a bony defect leading into the infraorbital sinus along the dorsorostral aspect of the right eye. Histopathology revealed an unencapsulated, poorly demarcated, highly cellular neoplasm composed of islands and trabeculae of neoplastic cells embedded in abundant loose fibrovascular stroma which completely obliterated the cortical bone and sinuses of the rostral skull and infiltrated the surrounding muscle and soft tissue. Histologically, the tumor was consistent with a high-grade mucoepidermoid carcinoma, characterized by the presence of epidermoid, intermediate, and mucous-producing cell types. No evidence of metastasis was identified. The tissue of origin was suspected to be salivary or nasal mucous glands, but was difficult to confirm due to distortion of normal tissue architecture as a result of the tumor. Although mucoepidermoid carcinomas are a common salivary gland tumor in human medicine, they are not well recognized in avian species, and no specific case reports exist describing this pathology in an Amazon parrot. Despite the lack of distinct salivary glands in most avian species, mucoepidermoid carcinomas can occur, can cause significant clinical disease, and should be included as a differential diagnosis for avian patients presenting with similar lesions.

Histopathological and immunophenotypical characterization of a combined melanoma and mucoepidermoid carcinoma in a dog / Simultaneous canine mucoepidermoid carcinoma and melanoma

The present paper reports the fi rst case of a canine high-grade (low differentiated) mucoepidermoid carcinoma,in which malignant proliferation of melanocytes has been detected. The tumoral mass was located in the lowerneck, pressing against the 7th cervical vertebral body in an aged dog of mixed breed. No macroscopic signsof skin or oral melanoma or carcinoma were detected elsewhere. The microscopic examination showed closeintermingling of the two components. Melanocytic proliferation rarely occurs accompanied by the colonizationof nonmelanocytic tumors, and the cause of such proliferation remains unclear. In human pathology, severalreports of pigmented mucoepidermoid carcinomas have been described, and in all cases the proliferationof the melanocytic component was considered as hyperplastic, and no sign of malignant proliferation wasdetected. However, neither in human nor in veterinary pathology has a case of intermingled melanoma andmucoepidermoid carcinoma been described(AU)

El presente trabajo describe el primer caso de un carcinoma mucoepidermoide canino pobremente diferenciadoen el que se ha observado una proliferación maligna de melanocitos. La masa tumoral se localizó a niveldel 7º cuerpo vertebral en perro de raza mestiza. No se detectaron otros signos macroscópicos de carcinoma y/o melanoma oral o epitelial. El examen microscópico reveló la proliferación conjunta de ambas subpoblaciones.La proliferación y colonización de melanocitos en tumores de origen no melánico es rara y no se conoce la causa.En Patología humana, se han descrito casos de carcinomas mucoepidermoides pigmentados, pero en todoslos casos se consideró la proliferación melanocítica como hiperplasia, no observándose en ningún caso signosde neoplasia. No existen en Patología humana ni veterinaria ningún caso descrito de carcinoma mucoepidermoideconcomitante con un melanoma maligno, siendo éste el primer caso descrito(AU)

High-grade mucoepidermoid carcinoma of the mandibular salivary gland in a lion (Panthera leo).

A 13-year-old neutered male lion was presented with a primary neoplasm arising from the left mandibular salivary gland associated with metastases to regional lymph nodes, thoracic viscera (lungs, heart, esophagus, and diaphragm), and kidney. Histologic and immunohistochemical investigations led to a diagnosis of a high-grade mucoepidermoid carcinoma of the mandibular salivary gland. In this case report, we point out the importance of the immunohistochemical characterization for differential diagnosis between various types of carcinomas of the salivary gland.

Naturally occurring mucoepidermoid carcinoma in the submandibular salivary gland of two mice.

Mucoepidermoid carcinomas in two mice were investigated histologically, immunohistochemically and ultrastructurally. The neoplastic cells showed divergent differentiation into periodic acid-Schiff-positive mucous cells, keratin-positive squamous cells, and cells with both mucous granules and sheaves of tonofilaments. Gland formation and keratinization were not observed. At the periphery of tumour cell nests, some cells were immunolabelled for smooth muscle actin or contained concentrated thin filaments, and these observations were interpreted to indicate that murine mucoepidermoid carcinomas are associated with both myoepithelium and duct epithelium.