Bone tumors part 2
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Langerhans cell histiocytosis (LCH) is a rare bone disorder that can present in various ways, typically affecting children, and can mimic more aggressive conditions like Ewing sarcoma. Diagnosis relies on imaging findings which often reveal osteolytic lesions, and treatment varies based on the extent of organ involvement and patient age. Differential diagnoses include eosinophilic granuloma, osteomyelitis, and Ewing sarcoma, with imaging shown to assist in distinguishing these conditions.
Bone tumors part 2
- 1. BONE TUMORS PART 2 Ramin Sadeghi, MD
- 2. LANGERHANS CELL HISTIOCYTOSIS OR EOSINOPHILIC GRANULOMA Langerhans cell histiocytosis replaces the other descriptive terms for this idiopathic disorder that included histiocytosis X and eosinophilic granuloma. EG may present as a well-defined osteolytic lesion with a benign periosteal reaction or as an aggressive lesion with ill-defined margins and an aggressive type of periostitis mimicking Ewing sarcoma or osteomyelitis. MRI usually demonstrates a large amount of edema. Favorite location: skull and femur, but may occur anywhere. In the spine EG may present as a collapsed vertebra or vertebra plana. In the skull usually the outer and inner table are destroyed as seen on CT.
- 4. LCH LCH is a rare disease and its estimated annual incidence is 0.05–0.5 per 100,000 children in the United States. Males are slightly more commonly affected than females (2:1) and it is commoner in Caucasians. Cases usually present under 30 years of age, with the mean age being 5–7 years. It can present from the neonatal period up to old age. very young children can present with life threatening LCH involving all organs (often sparing the kidney and gonads), while in the older patient there may just be a single organ (often bone) involved with a 100% survival rate and no residual symptoms The commonest signs and symptoms are those localised to the musculoskeletal system which includes bone pain, limb tenderness and so tissue swelling.
- 5. Eosinophilic granuloma Here some examples of EG demonstrating the various more or less aggressive presentations as ill-defined osteolytic lesions (blue arrow) and even as a less common sclerotic lesion (red arrow).
- 6. Eosinophilic granuloma On the left a well-defined osteolytic lesion. A zone of sclerosis can be seen surrounding the lytic lesion. Sometimes a so called button- sequestrum is found in the central part. The case on the right shows multiple ill-defined lesions in the parietal and frontal bone. Histology revealed eosiniphilic granuloma. In a young child with multiple lytic lesions of the neurocranium EG is the most likely diagnosis. The edge of the lesion often has a slightly beveled appearance, due to differential involvement of the outer and inner skull tables a loss of supporting structure around the teeth, the so-called a floating teeth
- 7. Eosinophilic granuloma On the left another case of EG presenting as a well-defined osteolytic lesion in a young child. Both inner and outer table of the skull are affected.
- 9. Eosinophilic granuloma On the left an ill-defined lytic lesion in the shaft of the femur with a solid layered periosteal reaction. Differential diagnosis: EG, osteomyelitis and Ewing sarcoma. Ewing sarcoma usually shows an irregular and interrupted periosteal reaction, however cannot be excluded. Axial T2-WI with FS shows high SI of the bone marrow and a soft tissue mass envelopping the bone.
- 10. Eosinophilic granuloma Here again the sclerotic lesion in the clavicle that was shown earlier. Notice on the T2-W MR-image the edema surrounding the clavicle. Based on these imaging findings differentiation from a malignant bone tumor or infection is not possible. Final diagnosis: eosinophilic granuloma.
- 11. Here a well-defined osteolytic lesion of the right clavicle. Diff. diagnosis: osteomyelitis, eosinophilic granuloma. T2-WI and T1-WI with Gd and Fs reveal the lesion with extensive osseous and soft tissue edema. Final diagnosis: eosinophilic granuloma.
- 12. Here a more aggressive appearance of eosinophilic granuloma. The radiograph shows a solid and interrupted periosteal reaction. Sagittal T1-WI and axial T2-WI with FS also show aggressive appearance with bone marrow and soft tissue edema. Differential diagnosis: Ewing sarcoma, osteomyelitis.
- 14. LCH Nuclear medicine The use of bone scintigraphy (Tc99m) in the detection of lesions in LCH is open to debate. Nuclear scintigraphy is less sensitive than radiographs in the detection of osseous lesions. While in the majority of cases there is increased uptake there may be areas of reduced uptake with a surrounding halo of increased activity. In children the normal physeal activity may mask the presence of some metaphyseal lesions. In some cases the uptake may be normal. Conversely areas of abnormal uptake may have no corresponding radiographic changes. Consequently radiographs and scintigraphy should be regarded as complementary imaging modalities. The use of other radiopharmaceuticals offers no advantage
- 15. EWING SARCOMA/PNET TUMORS Typical presentation: ill-defined osteolytic lesion with a moth-eaten or permeative type of bone destruction, irregular cortical destruction and aggressive periostitis in the lower extremity of a child. Plain radiographs usually illustrate the malignant nature. Based on the age, the location and the radiographic appearance the diagnosis of Ewing sarcoma can be made in over 70% of cases. In long bones, the tumor is most commonly located centrally in the meta- or diaphysis MR imaging reveals the soft tissue extension. Treatment of Ewing sarcoma consists of neoadjuvant chemotherapy, followed by surgical resection and adjuvant chemotherapy. The tumor also may respond to radiation therapy. Differential diagnosis: Osteosarcoma is frequently included in the differential diagnosis, particularly when reactive sclerosis is present. Primary lymphoma of bone also presents with permeative pattern of destruction and often a large soft tissue mass. The mean age of presentation in these patients is usualy higher than in Ewing sarcoma. In some cases osteomyelitis or eosinophilic granuloma may mimic Ewing sarcoma.
- 17. 1- ill-defined lytic lesion of the femur diaphysis with a permeative pattern of destruction. Notice reactive sclerosis, irregular periosteal reaction and soft tissue mass.DD: ostesarcoma, lymphoma 2- Ewing sarcoma of the chest wall presenting with a large soft tissue mass. Many Ewing sarcomas are accompanied with a large soft tissue mass. 3- Ewing sarcoma of the proximal femur: almost normal radiographic appearance! See next images. 4- ill-defined lytic lesion in the distal humerus. Layered periosteal reaction laterally and irregular periosteal reaction with interruption on the antero-medial side. 5- Ewing sarcoma of the iliac bone. Hardly visible on plain radiograph. Continue with the discussion of this case.
- 18. Ewing sarcoma (3) On the left images of a large lytic tumor arising from the right iliac bone. On the plain film it is very hard to appreciate the lesion because of the permeative destruction pattern. Scintigraphy shows extensive uptake within the iliac bone. Sometimes, a cold spot is found in Ewing sarcoma. MR reveals the intra- and extraosseous tumor extension.
- 19. Ewing sarcoma This case was also shown above. There is a Ewing sarcoma with permeative growth through the haversian channels accompanied by a large soft tissue mass as seen on the MR. The radiograph does not show any sign of cortical destruction. In fact it looks normal, although someone might argue that the cortex is somewhat ill-defined and that there maybe is some periosteal reaction.
- 20. Ewing sarcoma On the left a mixed lytic-sclerotic lesion within the diaphysis of the femur. There is a permeative pattern of destruction with a spiculated periosteal reaction and soft-tissue extension. The final diagnosis was a Ewing sarcoma. Based on these images osteosarcoma should be in the differential. Ewing sarcoma continued The fat suppressed T1-weighted enhanced MR image demonstrates the permeative cortical destruction and enhancing soft tissue mass.
- 21. Ewing sarcoma On the left a similar case. On the radiograph there is a subtle interrupted periosteal reaction of the humeral diaphysis with otherwise normal appearing cortical bone. Axial T2-weighted MR image with FS shows large accompanying soft tissue mass with almost normal appearing cortical bone. This suggests a malignant small-cell tumor like Ewing sarcoma or lymphoma. Final diagnosis: Ewing sarcoma
- 22. Ewing sarcoma Treatment for Ewing's sarcoma includes surgery, radiation and chemotherapy. On the left a Ewing sarcoma, presenting as a large pleural soft tissue mass (same case as above). On the right, the soft tissue mass has completely resolved after neoadjuvant chemotherapy.
- 23. Here a young patient with an ill-defined lytic lesion of the distal humerus. There is irregular cortical destruction and partially interrupted periosteal reaction. Final diagnosis: Ewing's sarcoma. Diff. diagnosis: osteosarcoma.
- 29. EWING SARCOMA/PNET TUMORS For locoregional tumor staging, MRI is the imaging modality of choice. At initial presentation, 20%–30% of patients have pulmonary and/or skeletal metastases. Classically, work-up for distant metastases includes a CT scan of the chest to evaluate pulmonary metastases and a bone scintigraphy to evaluate the entire skeleton for osseous metastases. PET-CT is getting more and more common for staging and response to therapy.
- 30. NONOSSIFYING FIBROMA/FIBROUS CORTICAL DEFECT The related fibrous cortical defect (FCD) and NOF are both similar lesions histologically, and distinction between the two has been arbitrarily designated as being based on size These two lesions are the most common benign bone lesions, with an estimated incidence of 30–40% in asymptomatic children and teens. These lesions are rarely seen in children younger than 2 years of age, and are not usually seen above 20 years of age. The origin of NOF and FCD is felt to relate to local trauma that is often unrecognized, and occurs at the site of muscular attachment onto the periosteum, with focal edema and hemorrhage occurring. is may explain why lesions are rarely seen in children younger than 2 years of age
- 31. NONOSSIFYING FIBROMA/FIBROUS CORTICAL DEFECT Eccentric well-defined lytic lesion with sclerotic lobulated margin. Usually located around the knee in diaphysis or meta/diaphysis and does not occur in hands, feet, spine and flat bones. Found as incidental finding or presents with a fracture. The natural course is a sclerotic filling over time.
- 32. Typical case of non-ossifying fibroma. Notice the sclerotic borders in this well- defined eccentric lytic lesion.
- 33. Same patient on MRI: eccentric well- defined lesion with intermediate to low SI on T1-WI and low to high SI on T2-WI; sclerotic margin, no surrounding edema.
- 34. The lesion may become quite large and may then mimic fibrous dysplasia or ABC. First presentation with a fracture is frequently seen.
- 35. Eccentric well-demarcated lesion with lucent areas, thin ridges and groundglass attenuation. Differential diagnosis: fibrous dysplasia, giant NOF. MRI in the same patient: well-defined, eccentric somewhat lobulated lesion with heterogeneous SI on T1-and T2-weighted fatsuppressed sequences.
- 36. On the left an incidental finding in a young adult without any symptoms of the upper leg. There are eccentric well-defined sclerotic lesions. This is typical for multiple non-ossifying fibromas with sclerotic fill-in. No further imaging is required and no biopsy.
- 39. SIMPLE BONE CYST Well-defined osteolytic lesion most frequently seen in the proximal humerus (55%) or proximal femur (20%) Tendency to migrate from the metaphysis to the diaphysis during growth Centrally located with minor or mild expansion only May present with a fracture after a minor trauma. So called fallen fragment may be found DD: ABC or fibrous dysplasia
- 41. Left: Young patient with well-defined diaphyseal lucent lesion, with some expansion and cortical thinning. Diagnosis: SBC, differential diagnosis: ABC usually more expansion or fibrous dysplasia. Middle: Another young patient with well-defined expansile lucent lesion in the proximal meta-diaphysis of the fibula. Because of the expansion, ABC should be considered. Histology revealed SBC. SBC may migrate from metaphysis to diaphysis during growth. Right: A well-defined lytic lesion with sclerotic margin in the right iliac wing of an adult. Benign characteristics. Diagnosis is SBC. SBC can be encountered as an asymptomatic coincidental finding in the pelvis.
- 42. Here a well defined lytic lesion of the proximal humerus in a 11-year old boy. Minimal expansion and some ridges and no fluid sedimentation levels on T1- and T2-weighted MR images. First diagnosis should be solitary bone cyst. Differential diagnosis: Fibrous dysplasia with secondary cyst formation. Aneurysmal bone cyst (less likely).
- 43. Sharply-defined lytic lesion of the calcaneal bone. Differential diagnosis based on x-ray: Intraosseous lipoma Intraosseous ganglion. Solitary bone cyst. Aneurysmal bone cyst. Fibrous dysplasia. MR doesn't show signal intensity of fat or blood (sedimentation). Histology showed solitary bone cyst
- 44. Here a well-defined lytic lesion in the distal metaphysis of ulna with a fracture. T1-weighted MR image reveals some expansion. Axial fat-suppressed T2-weighted image demonstrates a single fluid level with linear fallen fragment (arrow), highly suggestive for traumatized solitary bone cyst.
- 48. DDX Aneurysmal Bone Cyst The degree of bone expansion and cortical thinning, and the location, may help differentiation. The presence of multiple septations and fluid-fluid levels on MRI also suggests ABC rather than SBC. Fibrous Dysplasia Cysts in fibrous dysplasia (FD) not uncommonly occur in the femoral neck and also in the proximal humerus. Ground-glass density in adjacent bone may abut the cyst and an extensive abnormality is often seen in long bones. The FD typically shows a thick surrounding rind of sclerosis and other bones may be involved. If presenting in a child, the disease is likely to be polyostotic.
- 49. ANEURYSMAL BONE CYST Aneurysmal bone cyst typically presents as a painful expansile or 'aneurysmal' well- defined osteolytic lesion in a patient younger than 30 years. On plain radiographs often ballooning with very thin peripheral bone shell and frequently internal thin bony ridges. Central or eccentric origin in the metaphysis or diaphysis of a long bone. In the spine located in the body or in both body and arch. Characteristic appearance on MR with fluid-fluid levels due to blood sedimentation. Peripheral enhancement of multiple small chambers is typical. ABC most frequently presents around the knee. Other locations include the proximal humerus or spine, but many other bones are possible.
- 50. ANEURYSMAL BONE CYST In the spine osteoblastoma may mimic ABC. In the proximal humerus or femur of young children there is frequently a differential diagnosis of ABC, SBC and fibrous dysplasia. Cavities filled with blood can also be found in giant cell tumor, osteoblastoma and chondroblastoma (i.e with secondary ABC).
- 52. ABC On the left a typical location for an ABC in the posterior elements of the spine. Notice the well-defined osteolytic presentation with multiple fluid-fluid levels on MR with the patient in supine position. The differential diagnosis based on the CT is: ABC, Osteoblastoma and Tuberculosis
- 53. ABC On the left images of an aneurysmal or expansile well-defined osteolytic bone lesion in the fibula. The T2-weighted MR-image shows the fluid content and on the T1-weighted image there is a subtle fluid-fluid level. Differential diagnosis: SBC or fibrous dysplasia with cystic changes
- 54. ABC On the left images of an aneurysmal or expansile well-defined osteolytic bone lesion in the proximal phalanx. Notice the expansion and the enhancing rim.
- 55. ABC On the left an expansile well-defined osteolytic lesion with a sclerotic margin in the talus. Axial PD-weighted image shows lobulated contours and cystic appearance with fluid-fluid level (arrow). Most likely diagnosis: ABC. Differential diagnosis: chondroblastoma with secondary ABC.
- 56. ABC – Surface type On the left two different patients with an intracortical or subperosteal osteolytic well-defined lesion in the tibia. The lesion on the far left was thought to be an adamantinoma because of the localisation in the anterior tibial cortex. At biopsy it proved to be an ABC. The image on the right is an adamantinoma. Continue with the additional examinations in this ABC.
- 57. Here the MR, bone scan and the sonogram of the same patient with ABC. On the axial T2WI with fat saturation subtle sedimentation is seen. The bone marrow is completely normal.
- 58. ABC Here another ABC in the talus. It is barely visible on the X-rays and was initially missed. MR shows typical fluid-fluid levels.
- 59. ABC On the left another ABC, located in the distal femur. The plain radiograph shows a layered periosteal reaction and Codman triangle in direct relationship to an expansile lytic lesion with a thin peripheral bone shell. CT also reveals the subperiosteal origin of the lesion with secondary involvement of the cortical bone. Axial T2-weighted image with fatsat and contrast enhanced T1-weighted image with fat sat show multiple fluid-fluid levels with rim enhancement of the cavities filled with blood. This is typical for an aneurysmal bone cyst.
- 63. INTRAOSSEOUS GANGLION Intraosseous ganglia are cystic lesions that usually occur in a subarticular location and show histology similar to that of so tissue ganglia. Age: 40-50 Younger in tarsal and carpal bones The majority of IOGs are subarticular, in long bones often extending to the metaphysis. e lesion is frequently eccentrically located. 76% of IOG are related to the weight-bearing surfaces of lower limb joints. Two thirds of lesions are found around the knee.
- 64. Here a lucent lesion in the proximal tibia epiphysis. It is well-defined with high SI on T2 WI with FS without reactive edema. Diagnosis: intraosseus ganglion. Diff. diagnosis: degenerative cyst.
- 65. Here a well-defined lucent lesion in the epiphysis of the proximal tibia in a young patient. The sagittal T2-WI with FS demonstrates that the lesion has high SI, but there is no extensive edema, which makes a chondroblastoma less likely. Diagnosis: intraosseus ganglion. Diff. diagnosis: degenerative cyst, chondroblastoma.
- 68. GEOD OR DEGENERATIVE CYST Also known as geode Well-defined lytic lesion with or without visible connection to a joint surface and may extend quite far from the joint. Associated with osteoarthritis with degeneration of cartilage. MR: homogeneous high signal intensity on T2 WI due to the synovial fluid within the lesion. Usually no or limited edema. In later stages the cysts may contain fibrous tissue and have a lower SI. Differential diagnosis: intraosseous ganglion and less freqently a chondroid tumor.
- 69. GEODS
- 70. Degenerative cyst Here a patient with arthrosis of the knee and a large well-defined osteolytic lesion in the epiphysis of the tibia. In young patients the differential diagnosis would include chondroblastoma, intraosseous ganglion and giant cell tumor. In this elderly patient with arthrosis this lesion is most probably a degenerative cyst.
- 71. Degenerative cyst Here a well-deined osteolytic lesion with sclerotic margins in a patient with features of arthrosis. Most likely diagnosis: degenerative cyst. No change during follow up.
- 72. Sagittal T2-WI with FS confirms subchondral location of cystic lesion with limited amount of edema. The differential diagnosis is degenerative cyst, ganglion and chondroblastoma. In a young patient this could be a chondroblastoma. This patient was older and there is some arthrosis. Diagnosis: degenerative cyst.
- 73. GIANT CELL TUMOR Presents as an eccentric lytic lesion with a geographic pattern of bone destruction, but can also have a more aggressive appearance with ill- defined borders. By far most giant cell tumors are seen around the knee. GCT is located in the epiphysis with or without extension to metaphysis and frequently abuts the articular surface. Most common bone tumor in adults aged 25 - 40 y. Differential diagnosis: ABC may have the same radiographic features but is found in a younger age group. Chondroblastoma is also located in the epiphysis, but is seen exclusively in the epiphysis without extention to the metaphysis and is seen in a younger age group. Metastases, especially in older patients.
- 75. Giant cell tumor On the left a giant cell tumor presenting as an eccentric lytic lesion in the medial epi- and metaphysis of the distal femur. There is a small transitional zone resulting in well-defined borders. Continue with the MR-images.
- 76. Giant cell tumor MR-images of the same patient. Sagittal T1-weighted TSE images before and after Gd. The tumor extends to the subchondral bone plate with endosteal cortical involvement. There is inhomogeneous enhancement. On T2-weighted image, the tumor has a remarkable low SI, which is commonly seen in GCT. There is surrounding edema with high SI.
- 77. Giant cell tumor On the left a typical giant cell tumor of the distal radius. Notice the aggressive appearance with ill-defined borders, extension to the soft tissues and destruction of subchondral bone plate. The localisation in the epiphysis and metaphysis is in favor of diagnosis of GCT. On the right a coronal T1-weighted CE image. There is diffuse heterogeneous enhancement, and extension to the radiocarpal joint and surrounding edema in bone and soft tissues.
- 78. Giant cell tumor (3) continued On the left images of the same patient during follow-up after curettage and cement-placement. There is soft tissue swelling with osteolysis of the bone adjacent to the cement. This indicates recurrent or residual disease.
- 79. On the left another GCT presenting as an ill-defined expansile lesion with a very subtle peripheral bone shell arising from the spinous processes C5 and C6. The sagittal T2-weighted MR-image with FS demonstrates multiple small cavities within the tumor, due to secondary ABC.
- 80. Giant cell tumor On the left a large lytic lesion originating from the sacral bone. CT prior to biopsy shows a lesion, that is entirely lytic without minerelization. Differential diagnosis in a patient of 50 years of age: metastasis, plasmacytoma, chordoma, chondrosarcoma (no calcifications present), giant cell tumor.
- 81. Giant cell tumor (4) continued On the coronal T1WI after Gd , the tumor shows diffuse enhancement of the intra- and extraosseous component, with the exception of multiple cystic cavities, which have a low SI on T1 and high SI on T2. These cysts are not uncommonly encountered in giant cell tumor.
- 82. On the left more examples of GCT around the knee. Notice that most of these lesions are well- defined and located in the epiphysis and extend into the metaphysis. Some extend onto the articular surface (yellow arrow and small red arrows). The lesion on the upper right has an ill- defined border with a broad zone of transition (blue arrow).
- 83. Here another typical giant cell tumor presenting as an osteolytic lesion in the epi- and metaphysis of the proximal tibia. Non-specific intermediate signal intensity on T1WI and mixed high and low SI on T2WI with FS. The low signal on T2WI is usually due to hemosiderin within the GCT.
- 84. Here a giant cell tumor in the fibula. There is a partially ill-defined expansile lesion of the proximal epi- and metaphysis of the fibula in an adult. A thin peripheral bone shell suggests benign lesion, although malignancy (e.g. metastasis) cannot be excluded. In younger patients ABC should also be considered.
- 85. Here an ill-defined expansile lesion with very subtle peripheral bone shell arising from the spinous processes C5 and 6. On the sagittal T2WI with FS multiple small cavities are seen within the tumor, due to secondary ABC.
- 92. LIPOMA OF THE BONE A lucent lesion with central calcification in the anterior os calcis is considered pathognomonic of an intraosseous lipoma. Confirmation of fat composition of a bone lesion by MR imaging or CT is usually sufficient to confirm the diagnosis of a lipogenic tumour of bone without the need to biopsy. Lipomas are composed entirely or partly of fatty tissue which is low attenuation (−40 to −60 HU) on CT demonstrates increased SI on T1- and T2-weighted MR images, which suppresses on STIR or fat-saturated T2-weighted sequences Age at presentation is very wide ranging from 4 to 85 years (mean 43 years), and sex distribution is roughly equal (M4:F3).
- 93. DDX Lipomas in the os calcis without central calcification mimic simple unicameral bone cysts . Elsewhere in the skeleton, the differential diagnosis may include non- ossifying fibroma, simple bone cyst, fibrous dysplasia, giant cell tumour, bone infarct and chondroid tumour.
- 97. FFIBROUS DYSPLASIA In general FD is lytic and well-defined, but can look like almost anything. Various presentation: bone deformity, discrete lucency, patchy, sclerotic, expansile and polyostotic. The deformity can be very prominent. FD may also contain cystic parts, calcifications and ossifications. Mostly found in children and young adults, but sometimes as coincidental finding at older ages Preferential sites: femur, tibia, rib, neurocranium and humerus. Located in diaphysis or metadiaphysis. Usually FD presents as a solitary lesion, but in about 10% it is polyostotic. In polyostotic disease femur and tibia are often simultaneously involved. Differential diagnosis: In young patients with location in proximal humerus or femur: solitary bone cyst or aneurysmal bone cyst. In eccentric locations: NOF or adamantinoma (tibia). When calcifications are present: chondroid lesion (enchondroma).
- 99. Fibrous dysplasia Here a polyostotic manifestation of FD. There are multiple lesions, which are partially lytic and partially mixed lytic/sclerotic. The radiographic appearance is determined by the extent of dysplastic bone and the amount of bone produced and the degree of calcifications and ossifications.
- 100. Fibrous dysplasia On the left images of a patient with fibrous dysplasia of the rib with remarkable expansion. Fibrous dysplasia can cause huge deformaties of bones. CT shows expansion and a peripheral zone of sclerosis. No internal matrix formation. Axial T2-weighted image shows mixed pattern of low and high SI within the expansile lesion.
- 101. Fibrous dysplasia Fibrous dysplasia can be monostotic or polyostotic. In this patient there are identical lesions within the proximal femur and left acetabulum. There is a groundglass appearance with focal areas of calcifications.
- 102. Fibrous dysplasia The appearance of FD may vary from entirely lytic (probably due to cystic degeneration) to entirely sclerotic. On the left images of a patient with polyostotic fibrous dysplasia, with lucent lesions in the proximal and mid- diaphyseal femur, and lesion with groundglass density and calcifications in the fibula.
- 103. Fibrous dysplasia Bone scintigram in 40-year old patient in the tibia shaft. Plain radiograph shows well-defined lesion with ground glass density and sclerotic margin. Features are not characteristic for adamantinoma, histology revealed fibrous dysplasia.
- 104. Fibrous dysplasia On the left images of a patient with polyostotic FD. On the far left a well-defined lytic lesion with groundglass appearance in the proximal femur diaphysis, consistent with fibrous dysplasia. T2-weighted MR image with FS reveals cytic degeneration of the fibrous dysplasia, which is a common finding. This patient has a second lesion in the shaft of the humerus with a pathologic fracture.
- 105. Fibrous dysplasia The radiograph on the left shows a mixed lytic-sclerotic lesion of the left iliac bone. Axial CT image on the right shows some broadening of the iliac bone with a ground glass appearance and no cortical destruction.
- 106. Here a patient with polyostotic fibrous dysplasia. Notice multifocal areas of high uptake on bone scintigraphy: acetabulum, femur diaphysis, tibia and ankle. The radiographs show ground glass abnormalities with or without calcifications.
- 113. ADAMANTINOMA Rare low-grade malignant lesion, exclusively found in the diaphysis of the anterior cortex of the tibia. In 10% of cases ipsilateral fibula is also involved Adamantinoma may present as a solitary focus or multicentric lucencies May extend into the marrow cavity. Plain radiographs and CT show cortical lucencies combined with sclerosis. On MRI, the lesion is lobulated with high signal intensity on T2- weighted images and strong enhancement after Gd-DTPA. Main differential diagnosis: fibrous dysplasia.
- 115. Adamantinoma Young patient with a lobulated lytic lesion within the anterior cortical bone of the proximal tibia. There is a second lucency separately more proximal within the cortical bone. Axail CT image prior to biopsy demonstrates the lytic appearance of the lesion within the thickened cortical bone. In the differential diagnosis could have been chondromyxoid fibroma or fibro- osseous lesion, however, the separate cortical lesion strongly suggests adamantinoma, which is almost exclusively found in the tibia and often multicentric.
- 116. Adamantinoma Adamantinoma of the tibia in another patient. There is an ovoid osteolytic lesion within the anterior cortical bone. Lobulated high signal intensity on axial T2-weighted image. There is no extension into the bone marrow. Homogeneous enhancement on T1- weighted image after Gd-DTPA.
- 117. Adamantinoma On the left a radiograph and CT-image of another typical adamantinoma. CT was performed prior to biopsy.
- 118. Here a mixed sclerotic-lytic lesion, cortically based in the tibia shaft in a 12- year old boy. There is also a lucent lesion in the cortex of the fibula. Differential diagnosis includes adamantinoma or osteofibrous dysplasia, based on the typical location, age (2nd- 3rd decade) and radiographic appearance. Biopsy showed adamantinoma. Continue with the MR.
- 119. Same patient. Sagittal T2-weighted fat-suppressed images demonstrate multiple foci of high SI within the cortices of tibia and fibula. Post-operative situation on the right. Care should be taken that each focus is entirely removed. MRI is pivotal for demonstrating the intramedullary and soft tissue extension.
- 120. Adamantinoma Here another patient with an adamantinoma. MR reveals also extension within the bone marrow compartment.
- 124. LYMPHOMA key facts: Affects adults. May arise in any bone, but most commonly in femur and pelvis. Mostly central in diaphysis, but may occur eccentrally in metaphysis Usually bone involvement in known NHL, but may uncommonly arise as an isolated primary bone tumor. Advanced lesion: highly permeative, often large soft tissue mass.
- 125. Here a NHL presenting as a non-specific ill-defined mixed osteolytic-sclerotic lesion in the proximal tibia.
- 126. Here a bone lesion in a patient with known NHL. The imaging findings are non specific.
- 130. MULTIPLE MYELOMA key facts: Most common primary malignant bone tumor Older adults Imaging: sharply circumscribed lytic lesions or diffuse demineralization. Isolated myeloma lesion without systemic marrow involvement is called a plasmacytoma.
- 132. Multiple punched-out lesions in the skull. This pattern is very characteristic fot multiple myeloma. Also known as Swiss cheese-pattern.
- 133. Multiple small osteolytic lesions in a patient with multiple myeloma.
- 134. Here a 67-year old male with pain in the left buttock area. There is an unsharp lytic lesion in the iliac wing. Axial MR images (T2 FD and T1 CE fat suppressed) demonstrate a tumor with a large associated soft tissue mass. Differential diagnosis: Metastasis Myeloma Lymphoma. Biopsy revealed plasmacytoma
- 137. POEM polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes
- 139. METASTASES key facts: In adults, especially those over age 40, metastatic tumors are about 100 times more common than primary malignant tumors. Usually multifocal, occasionally solitary. Benign appearance does not exclude a metastasis. Predilection for hematopoietic marrow sites and proximal long bones, vertebrae, pelvis, ribs, cranium. 75% of bone metastases originate from prostate, breast, kidney or lung cancer Pediatric metastases: neuroblastoma, rhabdomyosarcoma, retinoblastoma
- 140. The x-rays show a sclerotic lesion in a patient with breast cancer. This is an osteoblastic metastasis.
- 141. Osteolytic metastases Most metastases are osteolytic. They originate mostly from kidney, lung, colon and melanoma. Here a subtle osteolytic metastasis in the distal femur.
- 142. Sclerotic metastases Sclerotic metastases are osteoblastic. In patients over the age of 40 with a sclerotic lesion, your first thought is metastatic disease. In a patient younger than 40 years a sclerotic lesion is usually an incidental benign finding like an ossified NOF, bone island, osteoid osteoma or infection. Here a patient with both sclerotic and osteolytic metastases. It is a male patient, so your first thought is prostate cancer, which this patient had.
- 143. BONE INFARCT Key facts Typical presentation: central lesion in metaphysis or diaphysis with a well defined serpentiginous border. May resemble cartilaginous tumors. Causes: corticosteroid use, sickle cell disease, trauma, Gaucher's disease, renal transplantation. The term bone infarction is used for osteonecrosis within the diaphysis or metaphysis. If the osteonecrosis is located in the epiphysis, the term avascular osteonecrosis is used.
- 144. The radiograph shows typical bone infarcts in diaphysis and metaphysis of femur and tibia.
- 145. On MR imaging bone infarcts are characterized by irregulair serpentiginous margins with low signal intensity on both T1 and T2 WI and with intermediate to high fat signal in the center part. Enhancement after i.v. Gadolinium is usually minimal or absent (see right image). At the periphery of the infarct a zone of relative high signal intensity on T2WI may be found.
- 146. Here an almost identical case. Typical MR pattern of bone infarctions with peripheral serpentiginous zones of low SI and central area of fat. Some enhacement may be encountered surrounding the infarction. Differentiating a bone infarct from an enchondroma or low-grade chondrosarcoma on plain films can be difficult or even impossible. Cartilaginous tumors in particular chondrosarcoma may show endosteal scalloping, while a bone infarct does not. Chrondroid tumors are more frequently encountered than bone infarcts.
- 147. CHORDOMA key facts: Rare low-grade malignant tumor usually in older patients. Typical presentation: expansile, destructive bone lesion that may be associated with a soft-tissue mass. On MRI T2-weighted images will show very high SI, more or less lobulated like a chondrosarcoma. On CT there may be calcifications also resembling chondrosarcoma. Preferential site of origin: Sacro-cocygeal Skull base / clivus May occur anywhere in the spine, most commonly in body and arch. Chordoma does not metastasize, but local recurrence is commmon. Chordomas in the sacrococcygeal region may be cured by radical en bloc excision. Chordomas in the base of the skull are usually inaccessible to surgery but may respond to radiation therapy.
- 149. Here images of a patient with lytic lesions of the C2 and C3 vertebrae with cortical destruction posteriorly. The differential diagnosis based on the CT-findings includes primarily metastases and myeloma. The sagittal T2-weighted image with fat saturation demonstrates continuity between the abnormalities with soft tissue extension and compression of the myelum. Now our differential should also include chordoma which has its origin in the neural axis as it arises from notochord remnants.
- 150. Chordoma Here another case of the cervical spine. T2 weighted images with and without fat suppression. Notice the involvement of more than one vertebral level, extensive soft tissue mass and very high signal intensity.
- 151. Chordoma Here a large tumor in the sacral region which proved to be a chordoma.