Soft tissue mass in chest with rib erosion in X-Ray is seen in all except:

D i.e. Osteosarcoma Soft tissue mass with rib erosion can be seen in leukemia (osteolytic expanding geographical lesion caused by collection of leukaemic cells/chloroma-Grainger 1777 ), lymphoma (rib involvement is common with multiple lytic occasionally expanding lesions with soft tissue masses-Grainger 1779), Ewing's sarcoma (osteolytic destructive rib lesions d/ t primary Ewing's or secondaries from it b/o 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 a/w 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 - Leukemia/lymhomaQ -Ewing's sarcoma (most common malignant tumor affecting ribs of children & adult)Q, Neuroblastoma in children - Desmoid tumor, Osteosrcoma (rare) Primary Malignant - Multiple myeloma/Plasmacytoma (common) - Chondrosrcoma (calcified matrix; mc) - Askin tumor (PNET) uncommon tumor of intercostal nerves - Lymphoma, fibrosarcoma, osteosarcoma (rare)Q Primary Benign Tumor Fibrous dysplasia (most common; predomnantly posterior location) Osteochondroma (exostosis), Enchondroma (both at costo chondral/costoveebral 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, Paget's disease Brown's tumor of hyper parathyroidismQ Osteomyelitis (tubercular, fungal, actinomyces infection) Gaucher's disease, Hurler's syndrome (generalized expansion sparing proximal ends), Thalassemia (trabecular pattern & expansion most marked proximally)