Histiocytomas can affect dogs of any age, but usually occur in those less than two years. Histiocytomas are one of the most common tumors in this age group. The breed or sex of the dog does not appear to influence their development. Histiocytomas are benign and are not considered to be a health risk.
Histiocytomas usually occur as a solitary pinkish red mass, but more than one may be present at a time. Histiocytomas can appear on any location on the body, however, the vast majority of histiocytomas appear on the head, neck, trunk, ears, and limbs. These tumors appear rapidly and are small and round, often dome- or button-shaped. They may ulcerate.
In most cases, histiocytomas will disappear on their own in about 3 months. Histiocytomas should be removed if the tumor is still present after 3 months, if it is ulcerated or likely to be abraded, or if it cannot be distinguished from a malignant skin tumor.
If you see a small tumor that develops on your dog make sure to have it examined by your veterinarian.