<prompt> Pagets disease exceptVirus associationProgress to chondrosarcomaLess than 1 malignantOstesclerotic phase seen  <response>: Robbins basic pathology 9th edition page no 771,headingclinical Course, 3rd paragraph The development of sarcoma is a dreaded but founately rare complication of paget disease occuring in only an estimated 1of patients. The sarcoma are usually osteogenic. Paget disease is also known as Osteitis Deformans. 