Dermatohistopathology, the histopathological study of the skin can be defined by the root terms "derma" (meaning skin) and "histopathology".
…is valuable in investigation of skin disease, especially where initial investigations such as skin scrapes have failed to reveal a specific cause; where hormonal, autoimmune or neoplastic disease is suspected; or where there has been failure of response to treatment for the initial clinical diagnosis.
Skin Punch Biopsy
This is the most commonly used technique for collecting skin specimens for dermatohistopathoology in dogs and cats. In this technique a small instrument called a skin punch is used to remove a 4-6mm (about the diameter of a pencil eraser) of skin. A stitch is placed after the biopsy.
Not as common as punch biopsy, ellipse biopsy involves the removal of an elliptical piece of skin using a scalpel blade. Usually larger than a skin biopsy, the elliptical incision shape aids in healing.