title: Collagenous fibroma of the arm: a report of two cases.
abstract: A recently proposed addition to fibrous tumors in soft tissue was first described as desmoplastic fibroblastoma and later renamed collagenous fibroma. This tumor is clinically and morphologically distinct and benign. However, only a few series have been reported, and the clinicopathologic features are not widely recognized. We present two cases of collagenous fibroma of the arm. Both patients presented with an enlarging, well-circumscribed and mobile soft tissue mass. Magnetic resonance imaging showed areas of low signal intensity on both T1- and T2-weighted sequences. Needle aspiration cytology revealed nondiagnostic samples because of the low cellularity of the tumors. Each of the resected tumors was composed of low-cellular spindle- to stellate-shaped cells in a fibrous matrix with clear margination. After the marginal excisions, no recurrences were observed. Clinicians should be aware of this entity to prevent overtreatment, because imaging findings and cytologic features are similar to those of desmoid tumor.
authors.affiliation: Department of Orthopedic Surgery, Niigata University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Ogose
authors.forename: T
authors.initials: T
authors.lastname: Hotta
authors.forename: I
authors.initials: I
authors.lastname: Emura
authors.forename: T
authors.initials: T
authors.lastname: Higuchi
authors.forename: N
authors.initials: N
authors.lastname: Kusano
authors.forename: H
authors.initials: H
authors.lastname: Saito
mesh_terms: D000368:Aged; D001132:Arm; D001706:Biopsy; D003287:Contrast Media; D017809:Fatal Outcome; D005260:Female; D005350:Fibroma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA