Cutaneous Leiomyosarcoma with Multiple Visceral Metastases in a Domestic Pigeon.

A clinical examination of a 4-yr-old fantail pigeon revealed a large skin tumor in the area of the left wing. The tumor had solid consistency and a single cavity filled with fluid. During necropsy, multiple tumors of varied size and diameter were found in the liver, spleen, pancreas, and kidneys. A histopathological examination of the skin tumor revealed extensive multifocal neoplasia with a tendency to infiltrate, composed of polygonal, round, oval, and elongated cells forming a solid system with cellular bands and obliteration of intercellular boundaries. Multifocal necrosis was detected in the foci of neoplastic infiltration. Similar foci were present in the liver, pancreas, and lungs. In an immunohistochemical examination, tumor cells tested positive for smooth-muscle actin and vimentin. The diagnosis was cutaneous leiomyosarcoma with an uncommon feature of visceral metastases.