Collagenous fibroma (desmoplastic fibroblastoma) is a recently described rare benign tumor. Since this tumor was characterized by Evans in 1995, fewer than 100 cases have been reported in English literature with the largest series published by Miettinen and Fetsch. Preoperative radiological diagnosis is important to avoid over-treatment and unnecessary extensive procedures, but is difficult because diagnostic imaging findings for collagenous fibroma have not been established. Here we report the US and MRI appearance of a lesion localized deep under the deltoid muscle in a 34-year-old woman with a palpable painless mass. Histological findings were consistent with a collagenous fibroma. As far as we know, this is the first description of US appearance of a collagenous fibroma in English literature.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.