bromochloroacetic-acid and Monkey-Diseases

Spontaneous hepatic neoplasms were identified in two adolescent (<5 years of age) male cynomolgus monkeys (Macaca fascicularis). Monkey No. 1 had a solitary hepatocellular carcinoma (HCC). Monkey No. 2 had multiple discrete tumors consisting of several poorly circumscribed HCCs and a mixed hepatocholangiocellular carcinoma (MHC). Metastases were not evident in either monkey. Histochemical and immunohistochemical stains were used to assess phenotypic alterations in the tumors. Many or most neoplastic hepatocytes (NHs) of both monkeys stained positive for low-molecular-weight cytokeratin (LMWCK), cytokeratin (CK) 8, and CK 18. In monkey No. 1, small aggregates of NHs were positive for carcinoembryonic antigen (CEA), glutathione S-transferase-pi (GST), and alpha-fetoprotein (AFP), but NHs were uniformly negative for CK 7. NHs in monkey No. 2 were negative for CEA and AFP but were multifocally positive for GST and CK 7. Broad-spectrum cytokeratin (BSCK), high-molecular-weight cytokeratin (HMWCK), and CK 19 did not react with NHs of either animal. Neoplastic cells forming ductlike structures in the MHC of monkey No. 2 stained with LMWCK, CK 7, CK8, CK 18, BSCK, and GST but not with HMWCK or CK 19. Tumors in both monkeys had enhanced pericellular fibronectin staining. Nonneoplastic parenchyma of both monkeys contained multiple discrete foci of cellular alteration and scattered aggregates of hepatocytes with strong cytoplasmic staining for fibronectin. Staining patterns of these tumors demonstrate immunophenotypic heterogeneity of the neoplastic cells within individual tumors and variability among tumors. This information may serve as a useful reference for others encountering similar lesions in primates.

Topics: alpha-Fetoproteins; Animals; Biomarkers, Tumor; Carcinoembryonic Antigen; Carcinoma, Hepatocellular; Cholangiocarcinoma; Glutathione Transferase; Immunohistochemistry; Keratins; Liver Neoplasms; Macaca fascicularis; Male; Monkey Diseases

An adult, gravid, female pigtailed macaque (Macaca nemestrina) presented for facial swelling centered on the left mandible that was approximately 5 cm wide. Differential diagnoses included infectious, inflammatory, and neoplastic origins. Definitive antemortem diagnosis was not possible, and the macaque's condition worsened despite supportive care. Necropsy findings included a mandibular mass that was locally invasive and expansile, encompassing approximately 80% of the left mandibular bone. The mass replaced portions of the soft palate, hard palate, sinuses, ear canal, and the caudal-rostral calvarium and masseter muscle. Histologically, the mass was a neoplasm that was poorly circumscribed, unencapsulated, and infiltrative invading regional bone and soft tissue. The mass consisted of polygonal squamous epithelial cells with intercellular bridging that breached the epithelial basement membrane and formed invasive nests, cords, and trabeculae. The mitotic rate averaged 3 per 400× field of view, with occasional bizarre mitotic figures. Epithelial cells often exhibited dyskeratosis, and the nests often contained compact lamellated keratin (keratin pearls). The neoplasm was positive via immunohistochemistry for pancytokeratin, variably positive for S100, and negative for vimentin, smooth muscle actin, and desmin. The gross, histologic, and immunohistochemical findings were consistent with an aggressive oral squamous cell carcinoma. The neoplasm was negative via PCR for papilloma virus. In general, neoplasia in macaques is rare. Although squamous cell carcinomas are one of the most common oral neoplasia in many species, to our knowledge this case represents the first reported oral squamous cell carcinoma in a pigtailed macaque.

Topics: Animals; Carcinoma, Squamous Cell; Fatal Outcome; Female; Immunohistochemistry; Keratins; Macaca nemestrina; Monkey Diseases; Mouth Neoplasms

Ovarian cyst is common incidental finding in humans and many animals and includes follicular cysts, cystic rete ovarii and mesonephric duct cysts. Ovarian cyst is often associated with reproductive disorders in humans and animals. We found accidentally bilateral cystic masses in ovaries in an African green monkey. Grossly, the left and right ovarian cystic masses were single unilocular cystic structures measuring 0.6 and 1.8 cm in diameter, respectively. Histologically, both cysts were thin-walled structures that arose from the center of the ovary and displaced ovarian tissue peripherally. The cysts were lined by a single layer of nonciliated low cuboidal epithelium. Immunohistochemically, epithelial cells in the cysts were positive for cytokeratin, and the stromal cells were positive for smooth muscle actin but negative for vimentin. These results suggest that these ovarian cysts in an African green monkey are cystic rete ovarii. To our knowledge, this is the first report of cystic rete ovarii in African green monkeys and may be of value in relation to research of the pathogenesis and treatment of ovarian cyst.

Topics: Actins; Animals; Animals, Laboratory; Chlorocebus aethiops; Female; Immunohistochemistry; Keratins; Korea; Monkey Diseases; Ovarian Cysts; Stromal Cells; Wolffian Ducts

An adult sooty mangabey (Cercocebus atys) with a solid mass arising from the skin of the dorsolateral cervical area was presented to the veterinary clinical staff. Grossly, the mass was firm, elongated, ulcerated at the tip, and measured 2.7 x 2.0 x 2.3 cm. It was surgically excised and then submitted for histopathologic evaluation. On histopathology, this tumor was composed of irregular masses and cords of neoplastic squamous epithelial cells that invaded the dermis and subcutis, often undergoing keratinization and forming numerous keratin pearls. On the basis of these histologic findings, the mass was diagnosed as a squamous cell carcinoma. Additional tests, including hematologic evaluations and radiographic views of the abdominal, thoracic, and cervical areas, were normal. Sections of the tumor were analyzed by electron microscopy and showed no evidence of viral particles. To the authors' knowledge, this is the first reported case of a spontaneous cutaneous squamous cell carcinoma in a sooty mangabey.

Topics: Animals; Animals, Laboratory; Carcinoma, Squamous Cell; Cercocebus atys; Histocytochemistry; Keratins; Male; Microscopy, Electron, Transmission; Monkey Diseases; Neck; Radiography; Skin Neoplasms

Squamous cysts and squamous epithelial plaques were observed in a total of seventeen cynomolgus monkeys. Eleven monkeys had squamous cysts, three of them also revealed squamous plaques and six revealed squamous plaques exclusively. At necropsy, cysts were recognized as yellow-white nodules with a smooth surface, that were located superficially along the interventricular septum, on the surface of the left ventricle or the apex of the heart. Microscopically, cysts were lined by a flattened epithelium and filled with keratin. Occasionally the epithelium was multi-layered or replaced by a rim of foreign body-type multinucleated giant cells. All animals with squamous cysts came from Mauritius, while those with squamous plaques came from Mauritius, China and Vietnam. As discussed in man, squamous cysts and plaques in cynomolgus monkeys are considered to represent displaced foregut epithelium, that was sequestered in the dorsal mesocardium prior to closure of the pleuropericardial fold during early embryologic development.

Topics: Animals; Cardiomyopathies; Cysts; Epithelium; Female; Keratins; Macaca fascicularis; Male; Monkey Diseases

There are very few reports of proliferative prostatic lesions occurring spontaneously in nonhuman primates. We found that 15 of 19 glands in aged macaques contained one or more epithelial lesions in the cranial lobe. These originated in the basal cell compartment and were characterized as hyperplasia and benign neoplasia. The adenomas contained variable gland formation, with morphologic and immunohistochemical evidence of secretory, mucigenous, neuroendocrine, transitional, and squamous cell differentiation. These cell types are resident in the normal prostate or appear in metaplastic lesions, and their presence in the macaque tumors is consistent with differentiation of a stem cell along multiple phenotypic pathways. The macaque growths are similar to human prostatic basal cell lesions and could provide insights into their pathogenesis as well as cellular ontogeny and general mechanisms of carcinogenesis in this organ.

Topics: Aging; Animals; Antibodies, Monoclonal; Histocytochemistry; Humans; Keratins; Macaca mulatta; Male; Monkey Diseases; Prostate-Specific Antigen; Prostatic Hyperplasia; Prostatic Neoplasms

Topics: Ameloblastoma; Animals; Carcinoembryonic Antigen; Female; Glial Fibrillary Acidic Protein; Immunohistochemistry; Jaw; Jaw Neoplasms; Keratins; Macaca; Microscopy, Electron; Monkey Diseases

Topics: Adenocarcinoma; Animals; Carcinoembryonic Antigen; Cecal Neoplasms; Female; Hylobates; Immunohistochemistry; Keratins; Membrane Glycoproteins; Monkey Diseases; Mucin-1; Mucins; Muramidase

A spontaneous squamous cell carcinoma was diagnosed in the oral cavity of an adult female squirrel monkey (Saimiri sciureus). Immunohistochemical analysis of the neoplasm demonstrated cytokeratin and vimentin, but not S100 or desmin in the neoplastic epithelial cells.

Topics: Animals; Carcinoma, Squamous Cell; Desmin; Female; Immunohistochemistry; Keratins; Monkey Diseases; Mouth Neoplasms; S100 Proteins; Saimiri; Vimentin