IMAGING IN BONE TUMOURS........... – 2.pptx

IMAGING IN BONE TUMOURS........... – 2.pptx

1. IMAGING IN BONE TUMOURS – 2 MODERATOR – DR. PRASANTHI MDRD PRESENTOR – DR. SWETHA

2. GIANT CELL TUMOUR Also called as osteoclastoma Locally aggressive tumour Rarely malignant and metastatising Peak incidence – 20 to 30 years Occurs around the growth plate of long bones after the closure of growth plate

3. ASSOCIATIONS – PAGETS DISEASE OF BONE PHEOCHROMOCYTOMA – PARAGANGLIOMA DIAGNOSTIC CRITERIA Circumscribed osteolytic bone tumour involving the epipihysis Usual occurrence in skeletally mature person H istological evidence of numerous non-neoplastic osteoclastic giant cells and fewer neoplastic mononuclear cells usually without atypia

4. They typically occur in an eccentric position at the end of long bones in the mature skeleton with involvement of the subarticular regions. distal femur and proximal tibia : 50-65% distal radius: 10-12% proximal humerus: 4-8% thinning or partial destruction of the surrounding cortex generally contained periosteum possible erosion of the subchondral bone plate but only rare extension into the joint space

5. RADIOGRAPHIC FEATURES Osteolytic or radiolucent lesion Well defined non sclerotic margin Eccentric location Extension to subchondral bone Closed growth plates

6. PLAIN RADIOGRAPH Radiolucent bone tumour Narrow zone of transition Cortical thinning Frequent trabeculation No matrix mineralisation ON CT eccentrically located  solitary lucent bone lesions

7. MRI Used to demonstrate Hemorrhagic areas Surrounding bone marrow edema Soft tissue extension ON T1 Low to intermediate signal intensity ON T2 Heterogenous high signal intensity ON T1C Solid componnets will enhance

8. EWINGS SARCOMA Ewing sarcomas  are the second most common malignant primary bone tumors of childhood after  osteosarcoma arising from the medullary cavity with the invasion of the Haversian system. occurs in children and adolescents between 10-20 years of age lower limb: 45% femur most common pelvis: 20%

9. Ewing sarcomas usually present as moth-eaten, destructive, and permeative lucent lesions in the shaft of long bones, large soft tissue component and typical onion skin periostitis.   large with a wide zone of transition/poorly defined margin. Over 80% of Ewing sarcomas demonstrate extension into adjacent soft tissues .

10. ON PLAIN RADIOGRAPH Moth eaten Desteructive Lucent lesions Diaphysis of long bones Wide zone of transition Lamellated onion skin periosteal reaction

11. MRI T1:  low to intermediate signal T1 C+ (Gd):  heterogeneous but prominent enhancement T2:  heterogeneously high signal, may see hair on end low signal striations

12. MULTIPLE MYELOMA  multifocal proliferation of plasma cells based in the  bone marrow  It is the most common  primary malignant bone neoplasm in adult FOUR PATTERNS disseminated form : multiple well-defined "punched out" lytic lesions: predominantly affecting the axial skeleton disseminated form: diffuse skeletal osteopenia solitary  plasmacytoma a single large/expansile lesion most commonly in a vertebral body or in the pelvis osteosclerosing myeloma

13. Distribution of multiple myeloma mirrors that of red marrow in the older individual, and thus this is mostly encountered in the axial skeleton and proximal appendicular skeleton vertebrae (most common) ribs skull shoulder girdle pelvis long bones

14. PLAIN RADIOGRAPH Numerous well circumscribed , lytic bone lesion Puched out lucencies Raindrop skull Endosteal scalloping Generalised osteopenia

15. Whole-body low dose CT is also better to assess the risk of pathological fracture in severely affected bones as well as the presence of extramedullary lesions  MRI Five patterns have been described normal  bone marrow   signal diffuse involvement focal involvement combined diffuse and focal involvement variegated ("salt and pepper")

16. T1 typically low signal  high-grade, diffuse involvement may become isointense to adjacent normal marrow T2 with fat-suppression high signal infiltration of the ribs is probably best appreciated on T2 images with fat suppression, appearing bright : ‘ white ribs sign

17. BONE METASTASIS Bone (skeletal) metastases  are the third most frequent behind  lung  and  liver metastases . They result in significant morbidity in patients with  metastatic disease

18. Skeletal metastases invariably incite a mixture of bone resorption and bone formation and can thus take on one of three patterns, depending on the dominant process lytic (osteolytic) metastases sclerotic (osteoblastic) metastases mixed lytic and sclerotic metastases

19. Primary tumors that commonly metastasize to bone include : prostate cancer   (most common in males) breast cancer (most common in females) non-small cell lung cancer hepatocellular carcinoma renal cell carcinoma thyroid cancer

20. The distribution of skeletal metastases roughly mirrors the distribution of  red marrow , presumably reflecting increased blood flow in red marrow compared to  yellow marrow : Vertebrae lumbar spine more than thoracic spine and cervical spine ​ especially the posterior vertebral body, extending into the pedicles  pelvis proximal  femur proximal  humerus skull

21. As is the case with other bone lesions, skeletal metastases can be difficult to identify on plain films In many other cases, the lesion is visible due to destruction of the cortex, or the presence of visible sclerosis.

22. Lytic bone metastases Lytic bone metastases can arise from renal cancer non-small cell lung cancer (NSCLC) thyroid cancer melanoma non-Hodgkin lymphoma (NHL) breast cancer

23. lucent bone lesions thinned or absent trabeculae and ill-defined margins CT can detect osteolytic metastases better than plain radiographs MRI displays high sensitivity and high specificity for the detection of bone metastases

24. Lytic bone metastases typically have the following signal characteristics : T1:  low signal intensity T2:  high signal intensity DWI:  high signal intensity on high b-value, low signal intensity on ADC SWI:  low signal intensity on the inverted magnitude and phase images  T1 C+ (Gd):  enhancement

25. Sclerotic bone metastases Sclerotic  or  osteoblastic bone metastases  are distant tumor deposits of a primary tumor within bone characterized by new bone deposition or new bone formation. prostate carcinoma breast carcinoma transitional cell carcinoma (TCC) carcinoid medulloblastoma neuroblastoma

26. Plain radiograph Sclerotic bone metastases typically present as radiodense bone lesions that are round/nodular with relatively well-defined margins On CT, sclerotic bone metastases typically present as hyperdense lesions 

27. MRI T1:  low signal intensity T2:  low to isointense  SWI:  low signal intensity on the inverted magnitude and phase images  T1 C+ (Gd):  variable

28. THANK YOU