Most commonly histiocytomas are found in young dogs and appear as a small, solitary, hairless lump, although Shar Peis may be predisposed to multiple histiocytomas.

• 组织细胞瘤最常见于幼犬，通常表现为小的、单个的、无毛肿块，但在沙皮犬中常为多个肿块。