Commonest site of occurrence of chondrosarcoma is -

Ans. is 'a' i.e., Pelvis Chondrosarcomao A chondrosarcoma is a malignant tumor derived from cartilage cells and it tends to maintain its cartilaginous character throughout its evolution.o Highest incidence is in the fourth and fifth decades, and men are affected more often than womeno Most commonly involved bones are pelvis (most common), femur (2nd most common), humerus, ribs and shoulder girdles.o It may be at metaphysis or diaphysis.o This tumor is slow growing but can metastasise to distant siteo The usual presentation is dull ache or gradually enlarging mass.Radiological featureso Expansile, radiolucent lesion in the medullary cavity (concentric)o Endosteal scalloping.o Punctate comma shaped or popcorn calcification.Treatmento Surgery is the treatment of choice