OsteosarcomaBone NeoplasmsOsteosarcoma, JuxtacorticalFemoral NeoplasmsCell Line, TumorLeg BonesOsteoblastomaHumerusTumor Cells, CulturedDog DiseasesOsteoblastsSarcoma, EwingLung NeoplasmsChondrosarcomaMethotrexateGene Expression Regulation, NeoplasticDoxorubicinCell ProliferationTreatment OutcomeImmunohistochemistryNeoplasm MetastasisPrognosisMagnetic Resonance ImagingRetrospective StudiesAntineoplastic AgentsApoptosisTomography, X-Ray ComputedAmputationCisplatinNeoplasm Recurrence, LocalTime FactorsTibiaRNA, MessengerIfosfamide