Figure 1
foot lump
Painful foot lump
Painful foot lump!
SectionMusculoskeletal system
Case TypeAnatomy and Functional Imaging
Authors
P. Diana Afonso,R. Lourenço R, c. Bagulho
Radiology Department - Hospital Garcia de Orta, Portugal.
Connected authors
46 years, male
Clinical History
The patient was referred for a painful growing mass of the foot.
Imaging Findings
A 43 year-old man presented with a 6-month history of a painful growing mass on the dorsum of the right foot (Fig 1). An AP radiograph revealed an expansible, eccentric, well-defined bone lytic lesion, with barely sclerotic margins (Fig 2). MR (FSE sequences) showed an expansible nodular mass of the 1st metatarsal bone, abutting the articular surface, with marked low signal on T1-weighted images and higher and inhomogeneous signal on T2-weighted images (Fig 3). Bone scanning revealed no metastatic disease (Fig 4). Angiography reconfirmed its hypervascular nature (Fig 5). The differential diagnosis included foot enchondroma, giant cell tumour (CGT), aneurysmal bone cyst (ABC), chondroblastoma and intraosseous ganglion, Brodie abscess.Surgery was performed (Fig 6) and histologic examination revealed a bone giant cell tumour (Fig 7).
The patient recovered well after surgery.
The patient recovered well after surgery.
Discussion
Giant cell tumour (GCT) is a common neoplasm (4-5% of primary bone tumours) and consists of connective tissue, osteoclastic giant cells and a fibrous stroma. It's one of the few bone tumours that has a slight predilection for females (1.5:1). Even though GCT can be clinically aggressive, neither its radiographic nor histologic appearance can put them into a benign or malignant category. After surgical excision, they are considered benign unless they recur (5-15% are thought to be malignant). Malignant GCT can metastize to the lungs, and less frequently, to lymph nodes. Despite the presence of metastatic disease, the prognosis remains good, with the major difficulty being that of local recurrence.
Patients may present with pain, swelling, limited range of motion of the adjacent joint or, with a pathologic fracture.
Typically, lesions occur in the long bones (distal femur, proximal tibia, distal radius and ulna or proximal humerus). Additional sites of involvement include proximal femur, sacrum, ribs, vertebrae, hands and feet (talus and calcaneus are the most commonly affected, followed by metatarsal bones).
There are 4 classic radiographic criteria for diagnosing GCT in long bones:
1) mainly affects skeletally mature patients, with 80% occurring in patients between 20 and 50 years.
2) even though the exact site of origin of GCT has been controversial, when the radiologist sees this lesion it's already epiphyseal and abuts the articular surface.
3) eccentrically located.
4) associated with a narrow zone of transition and lacking surrounding sclerosis (80%–85% of patients, Lodwick 1B).
These rules do not apply in flat bones or in the apophyses, which have no articular surfaces and can have a sclerotic margin (Lodwick 1A).
Other useful, frequent criteria are a slightly expansile nature and the not unusual extension of the tumour into the soft tissue. Also, the absence of periosteal reaction (unless a fracture has occurred) and the lack of mineralized matrix should be kept in mind. The age of the patient and the lack of mineralized matrix help to distinguish GCT from other end-of-bone lesions. Cystic (secondary ABC) components, frequently with fluid levels levels resulting from haemorrhage and necrosis are common (14% of lesions), along with solid portions (the presence of both solid and cystic components allows distinction from primary ABC, which contains only cystic regions).
CT improves detection of cortical thinning, pathologic fracture, periosteal reaction, lack of mineralization and degree of osseous expansile remodeling compared with radiography.
MRI is superior to CT in delineating soft-tissue tumor extent. It reveals a relatively well-defined lesion with a low-signal-intensity margins, with low to intermediate signal intensity at T1- and T2WI in the majority of cases and a heterogeneous pattern of enhancement after gadolinium. This feature can be useful in excluding other subarticular lesions such as solitary subchondral cyst, intraosseous ganglion, Brodie abscess, and clear cell chondrosarcoma that demonstrate high signal intensity at T2WI. Areas of very low signal intensity on all sequences are not unusual and are due to deposition of hemosiderin.
Patients may present with pain, swelling, limited range of motion of the adjacent joint or, with a pathologic fracture.
Typically, lesions occur in the long bones (distal femur, proximal tibia, distal radius and ulna or proximal humerus). Additional sites of involvement include proximal femur, sacrum, ribs, vertebrae, hands and feet (talus and calcaneus are the most commonly affected, followed by metatarsal bones).
There are 4 classic radiographic criteria for diagnosing GCT in long bones:
1) mainly affects skeletally mature patients, with 80% occurring in patients between 20 and 50 years.
2) even though the exact site of origin of GCT has been controversial, when the radiologist sees this lesion it's already epiphyseal and abuts the articular surface.
3) eccentrically located.
4) associated with a narrow zone of transition and lacking surrounding sclerosis (80%–85% of patients, Lodwick 1B).
These rules do not apply in flat bones or in the apophyses, which have no articular surfaces and can have a sclerotic margin (Lodwick 1A).
Other useful, frequent criteria are a slightly expansile nature and the not unusual extension of the tumour into the soft tissue. Also, the absence of periosteal reaction (unless a fracture has occurred) and the lack of mineralized matrix should be kept in mind. The age of the patient and the lack of mineralized matrix help to distinguish GCT from other end-of-bone lesions. Cystic (secondary ABC) components, frequently with fluid levels levels resulting from haemorrhage and necrosis are common (14% of lesions), along with solid portions (the presence of both solid and cystic components allows distinction from primary ABC, which contains only cystic regions).
CT improves detection of cortical thinning, pathologic fracture, periosteal reaction, lack of mineralization and degree of osseous expansile remodeling compared with radiography.
MRI is superior to CT in delineating soft-tissue tumor extent. It reveals a relatively well-defined lesion with a low-signal-intensity margins, with low to intermediate signal intensity at T1- and T2WI in the majority of cases and a heterogeneous pattern of enhancement after gadolinium. This feature can be useful in excluding other subarticular lesions such as solitary subchondral cyst, intraosseous ganglion, Brodie abscess, and clear cell chondrosarcoma that demonstrate high signal intensity at T2WI. Areas of very low signal intensity on all sequences are not unusual and are due to deposition of hemosiderin.
Differential Diagnosis List
Bone giant cell tumour of the foot (first metatarsal bone)
Final Diagnosis
Bone giant cell tumour of the foot (first metatarsal bone)
References
[1] Helms C, Brant W (2006) Fundamentals of Diagnostic Radiology. Lippincott Williams & Wilkins, 3rd ed.
[2] Richmond BJ (2006) Musculoskeletal Imaging: The Requisites. 2nd ed.
[3] Miller T, Schweitzer ME (2005) Diagnostic Musculoskeletal Imaging. McGraw-Hill, 1st ed.
[4] Greenspan A (2001) Orthopedic Radiology - A practical Approach. Raven Press Publication, 3rd ed.
Case information
| URL: | https://www.eurorad.org/case/7836 |
| DOI: | 10.1594/EURORAD/CASE.7836 |
| ISSN: | 1563-4086 |
Figure 2
AP radiographic view
Radiographic findings are often very suggestive - an expansile, eccentric, subarticular, well-defined bone lytic lesion is here seen. Note the lack of internal mineralization.
What would it be?
Figure 4
Bone scanning
Bone scintigraphy demonstrated increased radionuclide uptake and revealed no evidence of metastatic disease.
Keep in mind that most of giant cell tumours are solitary but can metastize, especially to the lungs!
Figure 5
Surgical specimen
Figure 6
histologic examination
Giant cells in a diffuse distribution in a background of mononuclear cells
Figure 7
Digital Subtraction Angiography
Angiography is infrequently performed since the advent of CT and MR angiography. However, due to a temporary setback with the MR gadolinium supplier, we chose to perform DSA to confirm tumor ´s hypervascularity.
foot lump
Painful foot lump
AP radiographic view
Radiographic findings are often very suggestive - an expansile, eccentric, subarticular, well-defined bone lytic lesion is here seen. Note the lack of internal mineralization.
What would it be?
Bone scanning
Bone scintigraphy demonstrated increased radionuclide uptake and revealed no evidence of metastatic disease.
Keep in mind that most of giant cell tumours are solitary but can metastize, especially to the lungs!
Surgical specimen
histologic examination
Giant cells in a diffuse distribution in a background of mononuclear cells
Digital Subtraction Angiography
Angiography is infrequently performed since the advent of CT and MR angiography. However, due to a temporary setback with the MR gadolinium supplier, we chose to perform DSA to confirm tumor ´s hypervascularity.