<prompt> True about Ameloblastoma: PGI Dec 2006Cystic lesionRapidly growingMalignant diseaseMC site is Tibia  <response>: Ans: A Cystic lesion Adamantinoma or Admantine Epithelioma or Ameloblastoma It is an epithelial tumor arising from ameloblast enamel forming cell. Its most common site is posterior mandible in the area of molar teethIt commonly presents in 3rd to 5th decades of life.It is a slow growing, locally invasive cystic benign tumor7 that causes expansion of outer table more than inner table of mandible. Cystic degeneration may lt softening egg shell cracking on palpation.It rarely metastasize and lt honey comb bubbly appearance on x-ray. Wider section of tumor is treatment of choice. Chemo radiotherapy has no roleApart from mandible, it is almost exclusively found in tibial diaphysis7 Late metastases to inguinal nodes lung can rarely occurMost common bone tumor of mandible is ameloblastomaQ but mot common tumorofja tvissaguomous cell carcinom a arising from oral mucosa over mandible.Also remember:Bone tumorMost common siteUnicameral Solitary Simple Bone cystQMetaphysis of proximal humerusQ femurAneurysmal Bone cystQFemur tibiaEnchondromaQMetaphysis of small bone of handsQ feetOsteochondroma Exostosis, m.e benign bone tumorQDistal femur upper tibia proximal humerusOsteoid osteomaFemur tibia diaphysisOsteosarcomaDistal femur Upper tibiaQ metaphysisEwings sarcomaQFemur Tibia diaphysisFibrous dysplasiaQUpper end femur 22 Tibia 21 Lower femur 12ChordomaQSacrum most commonQ sphenooccipital region clivus Q anterior vertebral bodyQ i.e. involves only axial skeletonQIvory osteomaFrontal sinusQAdamantinomaMandibleMultiple myelomaVertebraeQ 