Cutaneous smooth muscle tumors in 3 dogs

Jung, Ji-Youl; Kang, Sang-Chul; Park, Dae-Sik; Lee, Eun-Sung; Bae, Jong-Hee; Kim, Jae-Hoon

Korean Journal of Veterinary Research 2009;49(1):63-66.

Ji-Youl Jung¹, Sang-Chul Kang², Dae-Sik Park³, Eun-Sung Lee³, Jong-Hee Bae¹, Jae-Hoon Kim¹

¹College of Veterinary Medicine, Jeju National University
²Preclinical Research Center, Chemon
³Saha Animal Hospital

Abstract

Cutaneous leiomyomas (leiomyosarcomas) are smooth muscle tumors that occur single or as multiple lesions. They usually arise from the arrector pili muscles (piloleiomyomas) and less commonly from the muscle of veins (angioleiomyomas). This report describes histologic and immunohistochemical features of one cutaneous piloleiomyoma and two angioleiomyosarcomas. Three 7-12-year-old female dogs were presented with single or double cutaneous nodules. Histologically, the neoplastic masses were composed of densely or loosely arranged interlacing bundles. The neoplastic cells were ovoid to elongate, and had eosinophilic cytoplasms and perinuclear cytoplasmic vacuolation. Nuclei were central to eccentric, cigar shaped, oval to elongate. In two cases, high mitotic index in high power field, multifocal necrosis and local invasion were also noted. Masson's trichrome and van Gieson staining revealed muscle origin tumors in these cases. Immunohistochemically, the tumor cells were strongly positive for smooth muscle actin. In our best knowledge, this is the first report of cutaneous smooth muscle tumors in dogs in Korea.

Key Words: dog, immunohistochemistry, leiomyoma, leiomyosarcoma, skin