Whole blood samples (~15 to 20 mls) will be obtained from 90 humans over 3 years presenting to Duke with osteosarcoma. Only patients who would normally have blood drawn as part of standard care will be included. Research blood will be in addition to what is normally collected. Samples will be de-identified and then transferred to researchers as NC State's College of Veterinary Medicine. These researchers will use the samples to perform a CBC and evaluate monocyte phenotype and function. These results will be compared to published historical normal values for healthy human monocytes. This data will also be compared with canine data already gathered.