AJR 2002; 178:512-513
© American Roentgen Ray Society
MR Imaging of Squamous Cell Carcinoma Complicating Chronic Osteomyelitis of the Femur
Jonathan S. Luchs,
John Hines,
Douglas S. Katz and
Edward A. Athanasian
Winthrop University Hospital Mineola, NY 11501
Memorial Sloan-Kettering Cancer Center New York, NY 10021
A 61-year-old woman with a 50-year history of osteomyelitis of the left
femur presented with a painless soft-tissue mass in her distal posterior left
thigh and increased sinus tract drainage. Radiographs of the left femur
(Fig. 1A) showed expansion of
the left femoral cortex, with a diffusely abnormal mix of sclerotic and
radiolucent densities representing the known chronic osteomyelitis. An area of
increased soft-tissue density was also visible posterior to the distal femur.
MR images of the left thigh (Figs.
1B,1C,1D)
revealed marked periosteal thickening of the left femur. Decreased signal
intensity was evident on the T1-weighted images in the cortex and marrow of
the mid to distal left femur, and increased signal intensity was seen on the
T2-weighted images, consistent with chronic osteomyelitis. In the center of
the medullary cavity, a region of markedly decreased signal intensity,
representing the sequestrum, did not enhance with the administration of
gadolinium. Above the joint space, a posterior sinus tract led from the
medullary cavity to a subcutaneous mass. The mass, corresponding to the
palpable abnormality, had similar signal intensity to the adjacent periosteal
thickening on all sequences. The periosteum, the mass, and an extensive area
of cortex and the adjacent medullary bone enhanced substantially. The mass was
consistent with—and was subsequently proven by a percutaneous biopsy to
represent—squamous cell carcinoma. Because of the uniformity of the
signal and the similar enhancement of the mass compared with the cortex and
medullary cavity, it was impossible to determine the extent of invasion of the
bone by the mass, although the MR findings aroused suspicions of direct
extension of tumor into the cortex and medullary cavity.
View larger version (102K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —61-year-old woman with 50-year history of osteomyelitis of
left femur who presented with painless soft-tissue mass in distal posterior
left thigh. Lateral radiograph of left femur shows cortical expansion with
areas of medullary sclerosis and lucency consistent with chronic
osteomyelitis. Soft-tissue density (arrows) posterior to distal femur
is noted.
|
|
View larger version (133K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —61-year-old woman with 50-year history of osteomyelitis of
left femur who presented with painless soft-tissue mass in distal posterior
left thigh. Axial T2-weighted fast spin-echo MR images with fat suppression
obtained several centimeters above knee joint level (B slightly
superior to C) reveal markedly increased signal intensity in medullary
cavity (thick arrows) and sinus tract (curved arrows) that
leads from medullary cavity to posterior soft-tissue mass (thin
arrows, C).
|
|
View larger version (140K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1C. —61-year-old woman with 50-year history of osteomyelitis of
left femur who presented with painless soft-tissue mass in distal posterior
left thigh. Axial T2-weighted fast spin-echo MR images with fat suppression
obtained several centimeters above knee joint level (B slightly
superior to C) reveal markedly increased signal intensity in medullary
cavity (thick arrows) and sinus tract (curved arrows) that
leads from medullary cavity to posterior soft-tissue mass (thin
arrows, C).
|
|
View larger version (80K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1D. —61-year-old woman with 50-year history of osteomyelitis of
left femur who presented with painless soft-tissue mass in distal posterior
left thigh. Coronal T1-weighted axial gadolinium-enhanced, fat-suppressed MR
image shows enhancement of periosteum and cortex, as well as of mass and sinus
tract (arrows).
|
|
Surgical treatment consisted of removal of the entire tumor and en bloc
resection of the femur distal to the greater trochanter as well as the
proximal tibia. A Van Ness rotational repair was then performed. The specimen
was composed of a well-differentiated keratinizing squamous cell carcinoma of
the sinus tract, which had invaded the surrounding skin, soft tissue, and
bone.
Squamous cell carcinoma occurs in 0.23-1.6% of patients with chronic
osteomyelitis [1]. A draining
sinus tract must be present for squamous cell carcinoma to develop. The
chronic presence of purulent drainage causes repeated degeneration and
metaplasia of the epithelialized lining of the sinus tract, which can
subsequently lead to squamous cell carcinoma
[2]. Symptoms of malignant
change are not always present but may include worsening pain, an enlarging
mass, or an increase or change in the character of the draining fluid
[2]. Typically, a history of at
least 20 to 30 years of a draining sinus tract precedes the malignancy.
Radiographs may show new lytic change in the affected area; however, serial
radiographs may appear unchanged
[3]. The MR appearance of
squamous cell carcinoma complicating chronic osteomyelitis has, to our
knowledge, only been reported twice previously in the literature
[3,
4]. In one patient, T1-weighted
and short tau inversion recovery MR images revealed an intermediate-intensity
signal representing a soft-tissue mass that had surrounded and destroyed the
mid tibia [4].
References
-
Sedlin ED, Fleming JL. Epidermoid carcinoma arising in chronic
osteomyelitis foci. J Bone Joint Surg Am
1963;45:827
-838[Free Full Text]
-
Sankaran-Kutty M, Corea JR, Ali MS, Kutty MK. Squamous cell
carcinoma in chronic osteomyelitis. Clin Orthop
1982;198:264
-267
-
Sonin AH, Resnik CS, Mulligan ME, Murphey MD. General case of the
day. RadioGraphics
1998;18:530
-532[Medline]
-
McGrory JE, Pritchard DJ, Unni KK, Ilstrup D, Rowland CM. Malignant
lesions arising in chronic osteomyelitis. Clin Orthop
1999;362:181
-189
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
