Congenital desmoid fibromatosis in a Holstein heifer

Abstract

An 11-month-old, Holstein heifer was presented for a progressive swelling on the left side of the face that had been present since birth. A diagnosis of fibromatosis was made, based on macroscopic and microscopic examination of the abnormal infiltrative tissue. Because of the poor prognosis the animal was euthanized.

Figure 1

Left side of the heifer’s head showing a poorly circumscribed mass (between arrows). Dotted line represents the site of the cut section shown on Figure 2.

Figure 2

Cut section on the lateral aspect of the face showing a whitish fibrous-like mass with its thickest part marked with an asterisk.

Figure 3

Cut section through the masseter muscle showing thickened fascia (F) and obvious fibrous-like infiltration within the muscular tissue (arrow).

Figure 4

Histological appearance of the facial mass showing proliferating fibrous tissue infiltrating and dissecting adjacent tissues including skeletal muscles (M), adipose tissues (A), and muscular fasciae (F). HEPS stain. Bar = 200 mm. Inset: Close-up of the benign looking fibroblastic cells surrounded by blue-colored collagen fibers. Masson’s trichrome stain.