“Multiple histiocytic foam cell nodules in the tongue of miniature dachshund dogs.”
Miniature dachshund (MD) dog is a common breed in Japan and is known to be predisposed to granulomatous diseases such as suture granuloma, panniculitis and granulomatous gastroenteritis. Here we report multiple lingual nodules in seven MD dogs. In most cases, the multiple lingual nodules did not cause clinical manifestation; the nodules were found incidentally by the owners or veterinarians. Macroscopically, the multiple nodules of variable sizes were located mainly on the ventral and lateral surface of the tongue. The nodules were surgically excised in all cases. Three dogs had recurrence within 4 years after surgery. Metastasis was not observed in any case. Histologically, the nodules were composed of uniform foam cells with swollen, clear and vacuolar cytoplasm. The foam cells were positive for CD204 and MHC class II (macrophage markers), and negative for oil red O, PAS and alcian blue. The foam cells had little cellular atypia and had low proliferative activity. Based on these findings, the lesions were diagnosed as histiocytic foam cell nodules in the tongue. This disease occur preferentially in MD dogs and are considered to be reactive rather than tumor.