1. Bone tumors Primary: Secondary- COMMON Lesions similar to tumors
1-Benign is common
rare : 2-Malignant
Important -- Either disabling or fatal
Affect young age group
Secondary- COMMON
Lesions similar to tumors

2. Classification most system of classification depend on tissue origin and dominant tissue
1- osteoma, osteoid osteoma – osteoblastoma – osteosarcoma.
2- chondroma, osteochondroma, chondroblastoma, chondrosarcoma.
3- fibroma, fibrosarcoma, malignant fibrous histeocytoma.
4- haemangioma, haemangiosarcoma.
5- giant cell tumors.
6- Ewing's sarcoma

3. Diagnosis depend on 1- History and clinical examination:
Age, sex, history, physical examination.
2- Imaging:
X-ray , CT, MRI, Radionuclide scanning.
3 – laboratory investigation.
4- biopsy.

5. Differential diagnosis
1- infection.
2- Soft tissue haematoma and tendon injuries.
3- myositis ossificans.
4- Stress fractures and callus.
5 - Metabolic disorders and dysplasia.

6. Staging depend on aggressiveness and spread
Bone tumors staged to:
1- stage I – A : low grade sarcoma, intra-compartmental.
stage I – B : low grade sarcoma, extra-compartmental.
2 - stage II – A : High grade sarcoma, intra-compartmental
stage II – B : High grade sarcoma, extra-compartmental.
3 - stage III : Sarcoma with metastases.

7. Method of treatment 1- tumor excision. 2- limb sparing surgery.
3- amputation.
4- multi-agent chemotherapy.
5- radiotherapy.

8. Lesions similar to tumors
1- fibrous dysplasia. 2- fibrous cortical defect. 3- simple bone cyst. 4- anurysmal bone cyst. 5- eosinophilic granuloma.

9. Fibrous dysplasia

10. Eosinophilic granuloma

11. HAEMANGIOMA

12. Fibrous cortical defect (non ossifying fibroma)
Common benign lesion formed of a Cavity filled by Translucent fibrous tissue.
Usually discovered accidentally.
X- ray show well define osteolytic lesion in cortex of long bone metaphysis surrounded by a thin margin of dense bone.
No treatment or bone graft for large lesions.

14. Simple bone cyst solitary bone cyst or unicameral bone cyst
Appear during childhood typically in metaphysis of long bone, most commonly in proximal humerus.
Either presented as pathological fractures or found incidentally.
X-ray : well define central osteolytic lesion in metaphysis sometime attached to epiphyseal plate.
Cyst lined by thin fibrous tissue contain straw color fluid.

16. Treatment of simple bone cyst
Asymptomatic need no treatment.
Active cyst treated by aspiration and depomedrol injection. Aspiration and bone marrow injection is other alternative.
If cyst continue to enlarged or pathological fracture occur in weight bearing bone , the curettage and bone graft is the best treatment.

17. Anurysmal bone cyst
Tumor like lesion, lining membrane is thick soft tissue contain vascular cavities.
It affect metaphysis of long bone and vertebra.
It is expanding lesion, asymmetrical, thinning cortex.
X – ray: well define, trabeculated, eccentric metaphyseal osteolytic lesion.
Treated by curettage and bone graft

20. Osteoid osteoma
It is a benign tumor consisting of osteoid tissue and newly formed bone, it is less than 1 cm in diameter, oval or rounded and is encased by dense bone. Commonly affect the shaft of long bone in young age .
The main symptom is sever pain more at night ,relieved by aspirin.
X-ray: small radiolucent area surrounded by dense sclerosis. CT show lesion better, radioactive scanning show increased activity.
Differential diagnosis include: infection, callus of fractures, and tumors like Ewing's sarcoma
Excision of lesion cures the pain by open surgery or ablation by radiofrequency or leaser.
Lesion larger than one cm named osteoblastoma.

24. Compact osteoma (ivory exostosis )
Rare lesion cause localized thickening of bone affect outer or inner table of skull. The lesion is painless.
It may cause pressure symptoms.
X ray show well define sessile dense bone.
Excision if cause symptom is the treatment.

25. Osteochondroma cartilage capped exostosis
It is the most common tumor of bone.
It start as cartilaginous over growth at margin of epiphyseal plate and gradually ossified with growth. It grow with growth of body.
Continuous growth of mass after maturity suggest malignant changes.
It affect metaphysis, may be single or multiple (diaphyseal achalasia).
Patient may complain of pain, mass, interfere with movement or found accidentally.
The exostosis my be covered by tender bursa

27. X-ray show well define bone mass in metaphysis directed away from joint, look smaller the clinical examination because it covered by cartilage.
Treatment:
When exostosis cause symptoms it should be excised, or when it become painful or larger.
Malignant transformation is 1-2%

30. Chondroma ( enchondroma)
Benign cartilaginous tumor .it may be single or multiple (Ollier’s disease).
Commonly affect tubular bone of hand and feet and other long bone.
Patients may be presented as local pain or pathological fractures.
X-ray show well define osteolytic lesion with spot of calcification.
The lesion should be excised or curetted and replaced by bone graft.

33. chondroblastoma
Rare benign epiphyseal osteolytic lesion. Affect end of long bones Presented with pain.
X-ray well define epiphyseal osteolytic lesion, it may cross the epiphyseal plate to metaphysis
Treated by local excision and bone graft

34. Chondromyxoid fibroma
Rare benign lesion of metaphysis.
X ray show well define osteolytic oval or rounded eccentric, metaphyseal lesion with endosteal sclerosis.
Treatment: curettage and bone graft.