The patient went on to have an en-bloc resection. 

Left shoulder excision

Low grade (1/3) chondrosarcoma arising from a 7.5 cm osteochondroma of the posteromedial metaphysis of the humerus, with a maximal cartilage cap thickness of 2.4 cm (but also wrapping around much of the humeral head). Tumour extends into the glenohumeral joint space, but remains covered by reactive synovium. Negative for dedifferentiation.