Inclusion Criteria:  Patients with sarcoma on active chemotherapy/targeted therapy  Patients must have stable to mildly progressive disease or better on baseline assessment  Baseline measurement and follow-up measurement have to be performed on the same treatment for consistency. If patients with progressive disease are included into the study at baseline, follow-up measurement will be on a different treatment. Invariable, initiation of a new treatment, in the setting of progressive disease, lengthens oncology workflow which would affect the post measurement Patients must have been on the same treatment for at least 6 weeks Patients must have at least 3 prior imaging studies of the same body part/tracked lesion/area of interest separated by 6 weeks or more between studies Patients should be continuing same therapy for the next 6-8 weeks Patients must have plan for follow-up with imaging studies at MD Anderson Cancer Center (MDACC) while on therapy Patients who are receiving therapy outside of MDACC but having their follow-up imaging at MDACC are eligible >= 18 years of age  Exclusion Criteria:  Expected survival of less than 8 weeks Patients with an Eastern Cooperative Oncology Group (ECOG) performance status of 4