X-ray: Most useful of all imagingtechniques. There might be obvious abnormality of the bone: 1. Cortical thickening 2. Discrete lump 3. Cyst 4. defined destruction Is it in the metaphysis or diaphysis? Is it solitary or multiple lesions? Margins are well or ill defined? Note: cystic lesions are not necessarily hollow cavities: any radiolucent material may look like a cyst (e.g fibroma and chondroma) If the boundaries of the cyst is well defined, then it is mostly benign. If it is hazy and diffuse it is mostly invasive tumor. Bone surfaces: periosteal new bone formation and extension of the tumor to the soft tissues are suggestive of a malignant tumor. . Soft tissues: are the muscle planes distorted by the swelling? Is there any calcification? X-ray is not a definitive diagnosis and further investigation must be done to confirm. Other techniques of imaging used are: Radionuclide scanning-reveals site of small tumour CT-shows more accurately intraosseous and extraosseous extension of tumour MRI-useful for assessment of tumour spread They all help in viewing the lesions better. . view soft tissue and detect skip lesions too. Patient must not go for biopsy if MRI or CT is planned for him as it will distort the image and appearances. D. Imaging analysis: benign or malignant→ histology Location of the lesion Number of the lesion Bony destruction Hyperostosis Periosteal reaction Surrounding soft tissue changes chondroblastoma . A. E. F. B. C. Location and age of patient most important parameters in classifying a primary bone tumor. Simple to determine from plain radiographs. . metastasis tumor: flat bone. Location of the lesion Giant cell tumor: ending of long bone Osteosarcoma: metaphysis of long bone Ewing sarcoma: diaphysis Myeloma.A. irregular bone . . parosteal osteosarcoma . Central: Enchondroma Eccentric: GCT. osteosarcoma Cortical: osteoid osteoma. NOF Parosteal: osteochondroma. CMF. B Number of lesion Primary tumor: single frequent Metastasis: multiple Myeloma: multiple Giant cell tumor Multiple Myeloma Osteogenic metastasis . Patterns of bone destruction: •GEOGRAPHIC Lytic Well-defined smooth margin Short zone of transition •PERMEATIVE Poorly demarcated lesion imperceptibly merging with uninvolved bone Long zone of transition •MOTHEATEN Areas of destruction with ragged borders. Less well defined / demarcated lesional margin Longer zone of transition Sclerotic . . Slowly progressive process is “walled-off” by native bone. Rapidly progressive process destroys bone. producing indistinct margins. producing distinct margins.Margin between tumor and native bone is visible on the plain radiograph. 2. ◦ AND. . not all malignant diseases are aggressive. Aggressiveness increases likelihood of malignancy. to most aggressive 3 Aggressive lesions destroy bone. not all aggressive processes are malignant. 1C. 1B. Margin types 1A. and 3 ◦ least aggressive 1A. ◦ BUT. A well circumscribed lesion with a narrow zone of transition increasing aggressiveness . simple cyst (UBC) enchondroma FD chondroblastoma GCT chondrosarcoma (rare) MFH (rare) . GCT enchondroma chondroblastoma myeloma. metastatsis CMF FD chondrosarcoma MFH . chondrosarcoma MFH osteosarcoma GCT metastasis infection EG lymphoma . myeloma. metastases infection EG osteosarcoma chondrosarcoma lymphoma Multiple scattered holes that vary in size & seem to arise separately . numerous elongated holes/slots in cortex. run parallel to long axis of bone . metastasis lymphoma osteosarcoma Poorly demarcated from normal.Ewing EG infection myeloma. Limited responses of bone Destruction: Reaction: Remodeling: lysis (lucency) sclerosis periosteal reaction Rate of growth determines bone response ◦ slow progression. sclerosis prevails ◦ rapid progression. destruction prevails . Periosteal reaction must mineralize to be seen on X ray Configuration of periosteal reaction ◦ ◦ ◦ ◦ Nature of inciting process Intensity Aggressiveness Duration . uninterrupted ◦ long standing process. lamellated ◦ aggressive process ◦ tumor likely . often non-aggressive stress fracture chronic infection osteoid osteoma Spiculated. Thick. periosteal reaction Codman Triangle advancing tumor margin destroys periosteal new bone before it ossifies tumor . Sunburst Appearance . chondroblastoma. dots (stippled) ◦ enchondroma.“Matrix” is the internal tissue of the tumor Most tumor matrix is soft tissue in nature. ◦ Radiolucent (lytic) on x-ray Cartilage matrix ◦ calcified rings. arcs. chondrosarcoma Ossific matrix ◦ osteosarcoma . . . Osteolytic bone metastases: breast carcinoma shows multiple osteolytic bone lesions. . Osteoblastic bone metastases . Mixed pattern bone metastases: . + ALP and Anemia are non specific markers but may help in differentiating between malignant and benign bone lesion Osteosarcoma: Alkali Phosphatase (ALP) Ewing's sarcoma: WBC metastatic tumor & myeloma: secondary anemia and blood calcium Myeloma: Bence-Jones protein in urine .LABORATORY INVESTIGATIONS Blood Test : +ESR. . Excisional biopsy: for benign tumors.Principles of biopsy •From boundary or edge of tumor •Take several samples •Incision strategically placed •Ideally done by the treating surgeon •Wound closed without drain There are three ways: 1. Open biopsy: most reliable way of obtaining a representative sample.Needle biopsy: Must be performed by experienced personal with help of US or CT scan 2. 3.