System: Soft Tissue: Fibrous: Neoplastic: Desmoplastic Fibroblastoma
Stellate, bipolar, fibroblasts are sparsely distributed in a fibromyxoid stroma.
Desmoplastic fibroblastoma, also known as collagenous fibroma, presents as a slow growing painless mass in the subcutis. Most cases occur in adults and can arise in any anatomic location.
Grossly, these lesions are small (less than 4 cm), unencapsulated and fairly well circumscribed. Histologically, they are composed of stellate, bipolar, reactive-appearing fibroblasts sparsely distributed in a variably collagenous and myxoid matrix with few blood vessels. Tumor necrosis and mitotic activity are not seen (Fletcher, Evans).
Recent cytogenetic studies have found that at least some desmoplastic fibroblastomas exhibit t(2;11)(q31;q12) and this translocation is seen in fibroma of tendon sheath. These findings suggests that desmoplastic fibroblastoma may have a neoplastic nature and a possible relationship to fibroma of tendon sheath (Bernal, Sciot).
In a review of 63 cases of desmoplastic fibroblastoma, 80% occur in men with a median age of 50. The lesions exhibited a wide anatomic distribution with 24% arising in the arm, 19% shoulder girdle, 14% posterior neck or upper back, 14% in feet/ankles, 14% leg, 8% hand and 6% abdominal wall/hip (Miettinen).
Benign; simple excision suffices.
• Fibrous : Deep (Desmoid) Fibromatosis
Bernal K, Nelson M, Neff JR et al. Translocation (2;11)(q31;q12) is recurrent in collagenous fibroma (desmoplastic fibroblastoma). Cancer Genet Cytogenet. 2004 Mar;149(2):161-3.
Evans HL. Desmoplastic fibroblastoma. A report of seven cases. Am J Surg Pathol. 1995 Sep;19(9):1077-81.
Fletcher CDM, ed. Diagnostic Histopathology of Tumors. 3rd Ed. Philadelphia, PA: Elsevier; 2007: 1546.
Miettinen M, Fetsch JF. Collagenous fibroma (desmoplastic fibroblastoma): a clinicopathologic analysis of 63 cases of a distinctive soft tissue lesion with stellate-shaped fibroblasts. Hum Pathol. 1998 Jul;29(7):676-82.
Sciot R, Samson I, van den Berghe H, et al. Collagenous fibroma (desmoplastic fibroblastoma): genetic link with fibroma of tendon sheath? Mod Pathol. 1999 Jun;12(6):565-8.