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Age / Sex : 37 / F
Chief complaint: knee pain for 4 months
1) What is your impression?
Two weeks later, you can see the final diagnosis with a brief discussion of this case.
(Quiz는 quiz일 뿐이오니 답안은 한개만 보내주시기 바라오며, 복수의 답안을 보내주시는 분은 정답이 포함되어 있더라도 부득이 semi-correct answer로 처리토록 하겠습니다.)
Courtesy: 이소연(So-Yeon Lee), 강북삼성병원(Kangbuk Samsung Hospital)
Diagnosis: Giant cell tumor
Discussion
Findings: Coronal
and lateral knee radiographs show a geographic lytic lesion at distal femur with
a narrow zone of transition and no rim of sclerosis centered on the metaphyseal
side of the closed growth plate. MR imaging reveals
a well-defined lesion with a low-signal-intensity margin. The greater part of
this tumor demonstrates low to intermediate signal intensity at T1- and
T2-weighted MR images. Focal cortical thinning is visible at posterior cortex
of distal femur. There is perilesional bone marrow edema on fat-suppressed
T2-weighted images.
Differential Diagnosis: Clear cell chondrosarcoma
Diagnosis: Giant cell tumor
Discussion: Giant
cell tumor is a relatively common skeletal tumor, accounting for 4%–10% of all
primary osseous neoplasms and 18%–23% of benign bone neoplasms. Radiography often
suggests the diagnosis and reveals an eccentric, lytic lesion centered in the
metaepiphysis and extending to subchondral bone with expansile remodeling but
lacking internal mineralization. Giant cell tumor is typically benign and
solitary. However, multiple lesions have been described and 5%–10% of lesions
may be malignant. The vast majority of giant cell tumors affect skeletally
mature patients, with approximately 80% occurring in patients between 20 and 50
years of age. The peak prevalence is in the third decade of life. The most
common specific location of giant cell tumor
is about the knee (50%–65% of
cases). The single most common site is the distal femur, followed by the proximal
tibia, distal radius and, sacrum. As with other bone tumors, the differential
diagnosis of giant cell tumor is usually based on its radiographic appearance
and location. Lesions invariably demonstrate geographic bone lysis, most
commonly associated with a narrow zone of transition and lacking surrounding
sclerosis (80%–85% of cases) Cortical thinning of bone is invariably apparent
at radiography performed at clinical presentation. Expansile remodeling of bone
is also frequently seen (47%–60% of cases). Cortical penetration is seen in
33%–50% of cases, often with an associated soft-tissue mass. Periosteal
reaction is relatively unusual. Pathologic fracture is seen in 11%–37% of
patients. MR imaging of giant cell tumor frequently reveals a relatively
well-defined lesion with a low-signal-intensity margin representing either
osseous sclerosis or a pseudocapsule. However, more invasive and aggressive
growth may also be seen. The solid components of giant cell tumor demonstrate
low to intermediate signal intensity at T1- and T2-weighted MR imaging in the
vast majority of cases. This feature can be useful in excluding other subarticular
lesions such as large solitary subchondral cyst, in traosseous ganglion, Brodie
abscess, and clear cell chondrosarcoma that demonstrate high signal intensity
at T2-weighted MR imaging. ABC components in giant cell tumor are relatively
common (14% of lesions). In addition, giant cell tumor is the most common
lesion associated with secondary ABC, accounting for 39% of these lesions.
References:
1. Resnick
D, Kyriakos M, Greenway GD. Tumors and tumor-like lesions of bone: imaging and
pathology of specific lesions. In: Diagnosis of bone and joint disorders. 3rd
ed. Philadelphia, Pa: Saunders,1995; 3628–3938.
2. Murphey
MD, Nomikos GC, Flemming DJ, Gannon FH, Temple HT, Kransdorf MJ. From the
archives of AFIP. Imaging of giant cell tumor and giant cell reparative
granuloma of bone: radiologic-pathologic correlation. Radiographics.
2001;21(5):1283-309
3. Moser RP
Jr, Kransdorf MJ, Gilkey FW, Manaster BJ. From the archives of the AFIP. Giant
cell tumor of the upper extremity. Radiographics. 1990;10(1):83-102.
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