Desmoplastic Fibroblastoma of the Scalp Accompanied by Severe Pain; Unusual Location and Symptom

Desmoplastic fibroblastoma is a rare fibrous tumor that usually presents as a painless, slow-growing mass in the subcutaneous tissues and skeletal muscles. It has a wide anatomic distribution, with the most common involvement being the arm and shoulder. Here, we report a case of a tiny painful desmoplastic fibroblastoma arising on the scalp. According to a microscopic examination, this tumor was composed of spindle-shaped fibroblasts in the dense collagenous stroma. On immunohistochemical staining, tumor cells were positive for vimentin and negative for smooth muscle actin, CD34, and S100. Our case is unique in that desmoplastic fibroblastoma developed on the scalp and there was presence of pain despite its small size.

The MRI Findings of Collagenous Fibroma (Desmoplastic Fibroblastoma) Arising in the Supraspinatus Muscle: A Case Report

Collagenous fibroma (desmoplastic fibroblastoma) is a rare benign fibrous soft tissue tumor. This lesion commonly presents with painless, non-tender, mobile and slowly growing mass in subcutaneous tissue or skeletal muscle at various anatomic location. On magnetic resonance image (MRI), the mass shows area of low signal intensity on both T1- and T2-weighted pulse sequences. This low signal intensity presents areas of low cellularity in a background of abundant collagen. We describe the unique case of collagenous fibroma in the shoulder joint presenting with 4-years history of long-standing pain, which is unusual clinical manifestation of this benign soft tissue tumor without previous trauma history.

Collagenous Fibroma (Desmoplastic Fibroblastoma)

A Collagenous Fibroma (Desmoplastic Fibroblastoma) is a rare, benign, slowly growing, fibroblastic, soft tissue lesion. Here, the case of a 28-year-old woman, who presented with a 1-year history of a slowly growing painless mass in the right anterior aspect of her neck, is described. This type of tumor was first described by Evans in 1995, and named as a Desmoplastic fibroblastoma but was renamed, by Nielsen in 1996 as a Collagenous Fibroma. This type of tumor is frequently reported in men with a mean age at occurance of 50 years. Clinically, a Collagenous fibroma presents as a firm, well-circumscribed subcutaneous, or intramuscular, painless mass of long duration. They are mostly located in the neck and extremities. The tumors range in size from 1 to 20 cm and predominantly occurs within the subcutaneous tissue, but fascial and skeletal muscle involvement is common. The treatment of a Collagenous Fibroma is a total surgical excision. No tumor recurrence has been reported the literature during the follow-up period and no tumor recurrence was observed in our case at the 1-year follow-up.