Collagenous Fibroma (Desmoplastic Fibroblastoma): Different Localization. A Case Report

Collagenous fibroma is an extremely rare benign soft tissue tumor which arises in the subcutaneous tissue or muscle. We report a rare case of a collagenous fibroma in a 44-year-old woman who presented with a mass in the anterior chest wall. Microscopically, the tumor was hypocellular and consisted of diffuse bland spindle to stellate – shaped cells embedded in a collagenous stroma. Immunohistochemically, the tumor cells were diffusely and strongly positive for vimentin. Some cells contained alpha smooth muscle actin. They were uniformly negative for S-100 protein and CD34. After surgical excision, no recurrence or metastasis was observed during a 6 month follow-up period. A discussion of the histopathological features and a review of the literature is given.