<prompt> Soft tissue mass in chest with rib erosion in X-Ray is seen in all except:LeukemiaEwings sarcomaMultiple myelomaOsteosarcoma  <response>: D i.e. Osteosarcoma Soft tissue mass with rib erosion can be seen in leukemia osteolytic expanding geographical lesion caused by collection of leukaemic cellschloroma-Grainger 1777 , lymphoma rib involvement is common with multiple lytic occasionally expanding lesions with soft tissue masses-Grainger 1779, Ewings sarcoma osteolytic destructive rib lesions d t primary Ewings or secondaries from it bo large soft tissue component; while sclerosis when present should not be interpreted as tumor bone production, as seen in osteosarcoma, but is a secondary reactive phenomenon- Grainger 1646 and even Osteosarcoma, but it is rarest and is more commonly aw sclerosis and calcification. General rule: Rib erosion destruction is caused by many infective, granulomatous infections like TB fungal are more common, metabolic Pagets Brown tumor and neoplastic lesions. secondary more common than primary; and malignant primary more common than benign primary. Chondrosarcoma osteosarcoma have tendency to calcify. Causes of Expansile Focal Rib lesion Neoplastic Metastases Secondary Malignant - From bronchus, kidney, prostate or breast - LeukemialymhomaQ -Ewings sarcoma most common malignant tumor affecting ribs of children adultQ, Neuroblastoma in children - Desmoid tumor, Osteosrcoma rare Primary Malignant - Multiple myelomaPlasmacytoma common - Chondrosrcoma calcified matrix; mc - Askin tumor PNET uncommon tumor of intercostal nerves - Lymphoma, fibrosarcoma, osteosarcoma rareQ Primary Benign Tumor Fibrous dysplasia most common; predomnantly posterior location Osteochondroma exostosis, Enchondroma both at costo chondralcostoveebral junction Eosinophilic granuloma LCH, Xanthogranuloma Giant cell tumor, Aneurysmal bone cyst Osteoid osteoma, Osteoblastoma, Chondroblastoma Benign coical defect, Hemangioma, Enostosis bone island, lipoma, chondroma, neurofibroma Nonneoplastic Fibrous dysplasia, Pagets disease Browns tumor of hyper parathyroidismQ Osteomyelitis tubercular, fungal, actinomyces infection Gauchers disease, Hurlers syndrome generalized expansion sparing proximal ends, Thalassemia trabecular pattern expansion most marked proximally 