Not true about bone metastasis -

Ans is 'd' ie soft tissue sarcomas causes bony metastasis This is our best option to choose. This is the least correct option. Soft tissue sarcoma usually causes lung mets which is the most common site for its metastases. Other potential sites of metastases are bone, brain and liver. Axial bones are more commonly involved in bony metastasis and metastasis distal to elbow & knee are rare. Know the following impoant facts about bone metastasis * Skeletal metastasis may be osteolytic or osteoblastic. Although some tumors like renal cell carcinoma may produce purely osteolytic lesions majority of metastasis are mixed type - predominantly osteolytic. Predominantly osteoblastic lesions arise from - Prostate Also Remember Most common sites of primary for bone metastasis. - In males------------------ Prostate > Lung In Female---------------- Breast > Lung - In Children-------------- Neuroblastoma. Most common cause of osteolytic metastasis. - In males------------------ Lung Cancer - In Females---------------- Breast Cancer Most common cause of osteoblastic metastasis Skeletal sites most frequently involved - Spine > proximal femur > pelvis > ribs > sternum > proximal humerus > skull Lytic expansile metastasis seen in - Renal Cancer - Thyroid carcinomas Osteolytic lesions are associated with hypercalcemia and excretion of hydroxyproline - containing peptides. Osteoblastic lesions are associated with increased levels of serum alkaline phosphatase. Metastasis distal to knee and elbow is rare and usually arises from a primary tumors of the Bronchus Colon or Bladder