Bovine pulmonary blastomas: histomorphologic description and immunohistochemistry

Histological observations on aural fibrosarcoma in a Holstein cow

Fibrosarcomas occur as a mesenchymal tumour of malignant fibroblasts in a collagen background and are usually found in the female genital organs and rarely involve the skin. A 5-year-old female Holstein cow with a raised mass at the base of right ear was referred. On gross examination, the mass was approximately 13.00 × 10.00 × 7.00 cm in size. Finally, complete surgical removal was selected. The mass was encapsulated and the dermis was expanded by spindle-shaped to polygonal neoplastic cells. These cells were arranged in interwoven pattern. Mitotic figures were infrequent. Masson's trichrome demonstrated the positive and blue staining of collagen. Immunohistochemically, the sections were uniformly positive for Vimentin and negative for Desmin, SMA and GFAP. A well-differentiated fibrosarcoma was diagnosed based on histopathological features. Surgical excision is the treatment of choice for this neoplasm. In the present case, surgery was also performed successfully and no new growth of the mass was observed 4 months following the surgical procedures. To our knowledge, this is the first report of well-differentiated fibrosarcoma in a Holstein cow.

Pleuropulmonary blastoma in an equine fetus

Pleuropulmonary blastoma (PPB) is a rare biphasic tumor of children formed by mixed epithelial-and-mesenchymal elements. In this article, the authors report a pulmonary mass in an equine fetus with characteristics of PPB. A soft multicystic broad-based pleural mass was identified in the right caudal lung lobe. The mass comprised solid areas of loose mesenchyme, fenestrated by small ducts or large cystic areas lined by cuboidal epithelium. Mesenchymal elements had moderate anisocytosis, anisokaryosis, and cellular pleomorphism and were immunoreactive for vimentin. Epithelial cells lining ducts and cystic lumina were nonciliated and cuboidal with central round nuclei, minimal cellular pleomorphism, and strong immunoreactivity for cytokeratin. Pertinent characteristics in common with human PPB were the pleural-based location, the dual solid or delicate multiloculated cystic structure, the primitive mesenchymatous stroma fenestrated by well-differentiated cuboidal epithelial-lined lumina, and the occurrence during gestation.

Pulmonary neoplasia in two llamas (Lama glama)

Two llamas with pulmonary tumors were examined. Llama No. 1 had multiple nodules throughout the lung that consisted histologically of solid clusters of polygonal to spindle cells with rare glandular differentiation. Intravascular emboli were common. Similar neoplastic masses were present in the kidney, heart, and liver. Immunohistochemically, neoplastic cells were positive for broad-spectrum cytokeratins (CKs), high-molecular weight CKs, CKs 5/6, and vimentin. The diagnosis was pulmonary carcinoma. Llama No. 2 had pulmonary nodules without extrapulmonary involvement. Microscopically, neoplastic cells formed acini lined by simple epithelium and solid cords of squamous cells that sometimes surrounded acini. Neoplastic cells were strongly positive for broad-spectrum CKs and weakly positive for thyroid transcription factor-1. The diagnosis was adenosquamous carcinoma. Pulmonary tumors account for 23% of neoplasms in South American camelids in our laboratory, making this the second most common type of neoplasm after lymphosarcoma.

Pulmonary carcinosarcoma in a cat

A Domestic Shorthaired cat was presented with coughing and severe respiratory distress. Thoracic radiographs revealed a lobar mass and numerous additional cavitated intrapulmonary masses. The cat was euthanized and submitted for necropsy. Histological examination of the large mass revealed 2 distinct neoplastic components consisting of bronchial adenocarcinoma admixed with neoplastic areas composed of highly atypical undifferentiated spindle cells (sarcomatous component). Simultaneous expression of vimentin and cytokeratin by a subpopulation of neoplastic epithelial cells and by rare neoplastic spindle cells was identified. On the basis of histology and immunohistochemical results, a diagnosis of primary pulmonary carcinosarcoma with intrapulmonary epithelial metastases was made. Pulmonary carcinosarcoma is a well-known pathological entity in humans. It is a rare tumor in animals and has not been previously reported in cat.

Characterization of primary cell cultures as potential target cells for analysis of bovine cytotoxic T lymphocytes

In domestic animal species, assessment of cell-mediated immune responses to virus infection is hampered by the requirement for class I MHC compatibility between target and effector cells. Additional complicating factors can include an inability to infect target cells in vitro, or virus-induced lysis of infected target cells. One way to circumvent these problems is to use virus-mediated gene transfer to deliver individual viral genes to autologous primary target cells. Several primary bovine cell cultures were assessed as potential target cells for cytotoxic T lymphocyte (CTL) assays by measuring their levels of class I MHC expression and susceptibilities to retroviral gene delivery. High levels in both class I MHC expression and susceptibility to gene delivery were seen in adherent cell cultures isolated from peripheral blood (PBAC). PBAC, which arose as an outgrowth of adherent peripheral blood mononuclear cell cultures, had morphology, protein expression patterns, and response to functional assays characteristic of high endothelial cells. Expression of viral vector-delivered genes in PBAC cells was confirmed with a recombinant retrovirus carrying the green fluorescent protein (GFP) gene. The use of vector-mediated delivery of viral genes to bovine high endothelial cells is a promising method for assessment of cell-mediated immunity in cattle.

Respiratory diagnostic pathology

Effective treatment and control of bovine respiratory disease is dependent upon an accurate diagnosis. This article discusses the approach to diagnosis of bovine respiratory disease from the perspective of respiratory pathology. Topics covered include necropsy examination of the respiratory system, sample collection and submission, and the gross, and histopathologic lesions of the upper and lower bovine respiratory system.