Introduction

Benign cutaneous histiocytoma:

History:

A small nodule was seen on the lower eyelid of a 2 year old staffy dog. The nodule was alopecic (hairless) and pink in colour (arrowhead).

Histological appearance of neoplastic round cells in benign cutaneous histiocytoma. This neoplasm is derived from antigen-presenting Langerhans cells of the epidermis.

Benign cutaneous histiocytoma:

These round cell tumours can occur at any age but are most common in young dogs, especially on the face and ears. They are usually circumscribed and alopecic masses (“button tumours”) which commonly ulcerate. Typically, they grow rapidly and then spontaneously regress after weeks to months due to a cell-mediated immune response involving tumour infiltration by T lymphocytes.

Epitehlial Tumours

Mesenchymal Tumours

Round Cell Tumors

Review Questions

Back to Prac Classes