AJR 2004; 183:1766
© American Roentgen Ray Society
Radiologic–Pathologic Conference of Brooke Army Medical
Center |
Collagenous Fibroma (Desmoplastic Fibroblastoma) of the Shoulder
Kyle R. Walker1,
Liem T. Bui-Mansfield1,2,
Scott A. Gering3 and
Robert D. Ranlett4
1 Department of Radiology, Brooke Army Medical Center, 3851 Roger Brooke Dr.,
Fort Sam Houston, TX 78234-6200.
2 Department of Radiology, Wake Forest University, Winston-Salem, NC
27157-1088.
3 Department of Surgery, Brooke Army Medical Center, Fort Sam Houston, TX
78234-6200.
4 Department of Pathology, Brooke Army Medical Center, Fort Sam Houston, TX
78234-6200.
Received February 7, 2004;
accepted after revision April 2, 2004.
Address correspondence to L. T. Bui-Mansfield
(liem_mansfield{at}hotmail.com).
The opinions and assertions contained herein are those of the authors and
should not be construed as official or as representing the opinions of the
Department of the Army or the Department of Defense.
A52-year-old woman presented with a palpable mass in her right shoulder.
Findings of radiography of the humerus were normal. MRI revealed a solid 5.5
x 1.8 x 1.8 cm soft-tissue mass deep relative to the deltoid
muscle with low signal intensity on both T1- and T2-weighted pulse sequences
(Figs. 1A and
1B). An excisional biopsy was
performed, revealing a firm encapsulated mass. Histologic findings were
consistent with a collagenous fibroma (desmoplastic fibroblastoma)
(Fig. 1C).
View larger version (163K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —52-year-old woman with collagenous fibroma (desmoplastic
fibroblastoma) of right shoulder. Coronal T1-weighted (A) and
T2-weighted (B) fat-suppressed MR images of right shoulder show
well-circumscribed subdeltoid soft-tissue mass (arrow) of low signal
intensity on both sequences.
|
|
View larger version (137K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —52-year-old woman with collagenous fibroma (desmoplastic
fibroblastoma) of right shoulder. Coronal T1-weighted (A) and
T2-weighted (B) fat-suppressed MR images of right shoulder show
well-circumscribed subdeltoid soft-tissue mass (arrow) of low signal
intensity on both sequences.
|
|
View larger version (152K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1C. —52-year-old woman with collagenous fibroma (desmoplastic
fibroblastoma) of right shoulder. High-power photomicrograph of
histopathologic specimen shows scattered stellate cells in hypovascular
collagenous matrix without atypia or mitoses. (H and E, x400)
|
|
Desmoplastic fibroblastoma (collagenous fibroma) is a benign fibrous tumor
that occurs most often in patients during the fifth and sixth decades of life
with a male–female ratio of 5:1. Clinically, desmoplastic fibroblastoma
presents as a firm mobile painless slowly growing mass located in the
subcutaneous tissues or just deep relative to skeletal muscle. Fascial and
muscle involvement are common. This entity has been reported in the arm,
shoulder, posterior neck, upper back, abdominal wall, and hip joint. Size
ranges have been reported from 1 to 20 cm. Histologically, these hypocellular
tumors consist of stellate and spindle-shaped fibroblastlike cells that are
widely separated by a collagenous to fibromyxoid matrix. Only a few case
reports describe the MRI features of this tumor
[1–3].
On MRI, the lesion has low signal on both T1-weighted and T2-weighted pulse
sequences. The low signal intensity is attributed to the low cellularity of
the mass in a background of abundant collagen
[1]. It is important to
distinguish a desmoplastic fibroblastoma from other potential causes of low T2
signal in a soft-tissue mass to assist with clinical management.
Most soft-tissue masses have high signal intensity on T2-weighted images.
Soft-tissue masses with low signal on T2-weighted images include neurofibroma,
cicatricial fibroma, malignant fibrous histiocytoma, aggressive fibromatosis,
and calcified masses (myositis ossificans, extraskeletal osteosarcoma or
chondrosarcoma, and synovial sarcoma). In the absence of calcification,
abundant collagen and marked hypocellularity in a soft-tissue tumor result in
a decreased signal on T2-weighted pulse sequence
[4].
Treatment of desmoplastic fibroblastoma is surgical excision with no
reported incidence of local recurrence or metastases.
References
- 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;29:676
–682[Medline]
- Beggs I, Salter DS, Dorfman HD. Synovial desmoplastic fibroblastoma
of hip joint with bone erosion. Skeletal Radiol1999; 28:402
–406[Medline]
- Shuto R, Kiyosue H, Hori Y, Miyake H, Kawano K, Mori H. CT and MR
imaging of desmoplastic fibroblastoma. Eur Radiol2002; 12:2474
–2476[Medline]
- Sundaram M, McGuire MH, Schajowicz F. Soft-tissue masses:
histologic basis for decreased signal (short T2) on T2-weighted MR images.
AJR 1987;148:1247
–1250[Abstract/Free Full Text]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
