A 5-year-old boy was admitted with a diagnosis of orbital
cellulitis. A CT scan revealed an orbital mass that was
biopsied. Sclerosing inflammatory pseudotumor Sections show
fibrofatty tissue with areas of dense collagen. In other areas
there is a proliferation of spindled and stellate cells with
scanty cytoplasm that do not express muscle-specific actin.
Scattered among these fibroblasts are small numbers of
inflammatory cells, particularly lymphocytes but with A
pronounced inflammatory infiltrate is a recognised feature of
some soft tissue neoplasms. Inflammatory cells may also form a
major component of a variety of non-neoplastic space-occupying
lesions in soft tissue, some of which have a histological
appearance sufficiently characteristic for the lesion to have
been given a specific name, e.g. nodular fasciitis.
Fibroinflammatory lesions with a similar histological appearance
have been described in several specific locations and coexist
often enough for them to be recognised as related diseases.
These le