<prompt> A 33-year-old man presented with a slowly progressive swelling in the middle l3rd of his right tibia. X-rays examination revealed multiple sharply demarcated radiolucent lesions separated by areas of dense and sclerotic bone. Microscopic examination of a biopsy specimen revealed island of epithelial cells in a fibrous stroma. Which of the following is the most probable diagnosis?AdamantinomaOsteofibrous dysplasiaOsteosarcomaFibrous cortical defect  <response>: Ans- A Adamantinoma Adamantinoma characteristically presents in the tibial diaphysis of a middle aged person with mild to moderate discomfort, islands of epithelial cells in a fibrous stroma hall mark histologically, and bubbly bone destruction radiolucent lesions separated by dense sclerotic bone radiologically. Adamantinoma Key points Adamantine epithelioma or Lichtenstein dermal inclusion tumor. Almost exclusively found in tibial diaphysis Mild pain palpable mass over anterior tibial border Islands of epithelial cells Bubble like defect in anterior tibial cortex, sometimes with thickening of surrounding bone Treatment is wide local excision Bone Tumor Most Common Site UnicameralSolitarySimple Bone cyst Metaphysis of proximal humerus femur Aneurysmal Bone cyst Lower Limb Enchondroma Metaphysis of small bones of hands feet Osteochondroma Exostosis, m.c. benign bone tumor Distal femur upper tibia proximal humerus Osteoid osteoma Femur tibia diaphysis Osteosarcoma Distal femur Upper tibia metaphysis Ewings sarcoma Femur Tibia diaphysis Fibrous dysplasia Upper end femur 22 Tibia 21 lower femur 12 Chordroma Sacrum most comnmon sphenooccipital region clivus anterior vertebral body i.e. involves only axial skeleton Ivory osteoma or compact or Eburnated Osteoma Frontal sinus Adamantinoma Tibia MC lone bone Multiple myeloma Vertebrae Age predilection Tumor Age Range years Ewings tumor 5-15 Non ossifying fibroma Simple unicameral bone cyst 2-20 Aneurysmal bone cyst 5-20 Osteogenic sarcoma 10-20 Osteoclastoma GCT 20-40 Multiple myeloma Metastasis 40 