Abstract
Chondrosarcoma, Ewing sarcoma, osteosarcoma, multiple melanoma/plasma cell myeloma, metastases, undifferentiated high-grade pleomorphic sarcoma, fibrosarcoma, chondroma/enchondroma, Langerhans cell histiocytosis/eosinophilic granuloma, desmoplastic fibroma, aneurysmal bone cyst, giant cell tumor, fibrous dysplasia, and osteoid osteoma are the most common histological type of pelvic bone tumors. This chapter will illustrate the gross and histological features of these tumors; highlight the ancillary testing of diagnostic, prognostic, and predictive markers, and the collaborative opportunities between pathologists and orthopedic surgeons to improve the quality, safety, and value of patient care.