Malignant histiocytosis in a German Shepherd dog - a case report

Malignant histiocytosis is a systemic and progressive neoplastic disease with invasive proliferation of neoplastic histiocytes. A wound and swelling under the right forelimb and a mass on the pulvinus are shown on a German Shepherd dog. Histiocytosis is diagnosed pathologically. For necropsy; the smooth masses are located on right forelimb pulvinus, proximal metacarpal joint and adhering the tendon of cubiti joint. It infiltrates the prescapular and retropharyngeal lymph nodes, kidneys, lungs and epidermis. Neoplastic cells and multinuclear giant cells are shown as anaplastic characteristics with eosinophilic cytoplasm and vesicular nuclei with high mitotic activity.