<prompt> Which of the following is true regarding osteoid osteoma?The femur and tibia are the commonest bones involvedRadiologically appears as a radiolucent lesion surrounded by dense boneIt is a benign bone tumor, presents with severe pain that is typically relieved by aspirinAll of the above  <response>: Ans. d. All of the aboveOsteoid osteoma is a benign tumor that mainly affects young adults.The femur and tibia are the most common bones involved.Pain is often the presenting feature and relief by aspirin is almost diagnostic.Local surgery is curative.Comparison of osteogenic sarcoma, ewing sarcoma, and osteoid osteoma Osteogenic sarcomaEwing sarcomaOsteoid osteomaPresentationSecond decadeSecond decadeSecond decadeM:FSlightly greater in malesSlightly greater in males3x greater in malesPredispositionRetinoblastoma, radiationNoneMale genderX-raySclerotic destruction: sunburstLytic with laminar periosteal elevation: onion skinSmall round central lucency with sclerotic marginMalignantYesYesNoMetastasesLungs, boneLungs, boneNATreatmentChemotherapy, ablative surgeryRadiation andor surgery. NSAIDs. Surgery recommended when associated painPrognosis70 cure without metastasis at diagnosis60 cure without metastasis at diagnosisOver time it may resolve spontaneouslyOutcome If metastasis2020-30NARadiology of bone tumorsTumor typeCharacteristicsRadiological findingsOsteochondromaBony exostosis with cartilaginous chondroid capTGiant cell tumorSoap bubble appearance on X-rayROsteosarcoma osteogenic sarcomaCodman triangle from elevation of periosteum Or sunburst pattern on X-ray-Ewing SarcomaOnion skin periosteal reaction in boneMost common site involved in bone tumorTumor typeSite involvedOsteochondromaMetaphysisGiant cell tumorEpiphysisOsteosarcoma osteogenic sarcomaMetaphysisEwing sarcomaDiaphysisOsteoid osteomaDiaphysis Figure 