Treatment

The patient was referred to an oncologist for treatment.

Excisional Biopsy

Histologic examination reveals two pieces of soft tissue composed of surface epithelium with underlying fibrous connective tissue intensely infiltrated by numerous eosinophils intermixed with sheets of histiocytes. Some have grooved nuclei consistent with Langerhans cell morphology (Figure 4), while some have large nuclei, prominent nucleoli, and readily identifiable mitotic activity not typical of Langerhans cell morphology or behavior. The Immunohistochemistry stain with Cd1a (Figure 5) and S-100 (Figure 6) antibodies were uniformly positive.

Figure 4 High power (x200) H & E stained histology shows a mass of vascular granulation tissue containing sheets of large "histiocytes" and large aggregates of eosinophils.

Figure 5 High power (x200) Immunohistochemistry stain with antibody to CD1a, the "histiocytes" were uniformly positive with this antibody.

Figure 6 High power (x200) Immunohistochemistry stain with antibody to S-100, the "histiocytes" were uniformly positive with this antibody.