Gingival Vascular Hamartoma in a Neonatal Calf

Abstract

A neonatal Japanese Black calf (three-days-old) showed signs of anorexia. Clinical examination revealed a thumb-sized mass on the lingual area in relation to the right incisor of the mandible. Two days later, the mass was surgically removed and examined pathologically. Macroscopically, the mass had a nipple-shaped and segmented appearance with an off-white or tan-colored surface, and the gingival border appeared reddish. On palpation, it was soft. Histopathologically, the mass was composed of a proliferation of smaller blood vessels with irregular lumens and an increased number of well-differentiated vascular endothelial cells. Although these cells were oval-shaped and showed protrusion into the lumens, cellular atypia and mitotic figures were not observed. A proliferation of stromal cells with slight mucous was present in the edematous stromal tissues. On the basis of the histological findings, in this case a vascular hamartoma was diagnosed. This is the first case report of a vascular hamartoma in the gingiva of cattle in Japan.