['soft tissue sarcoma']
['olaratumab', 'doxorubicin']

        Inclusion Criteria:

          -  Have a histologically confirmed diagnosis of STS for which olaratumab and doxorubicin
             would be appropriate therapy. Participants with a diagnosis of Grade 1 liposarcoma are
             eligible if there is histological or radiographic evidence of evolution to more
             aggressive disease. Participants with Kaposi's sarcoma and gastrointestinal stromal
             tumors (GIST) will be excluded. Participants must have potentially resectable disease
             (as assessed by the study investigator) and have a primary tumor lesion deemed
             amenable to serial biopsy.

          -  For radiotherapy addendum only: Have a histologically confirmed diagnosis of STS of
             the extremities, Grade 2 or 3, >5 centimeters, for which olaratumab and radiotherapy
             would be appropriate therapy. Participants with Kaposi's sarcoma, GIST or myxoid
             liposarcoma will be excluded.

          -  Have consented to undergo mandatory serial peripheral whole blood and tumor tissue
             sampling.

        Exclusion Criteria:

          -  Have active central nervous system (CNS) or leptomeningeal metastasis (brain
             metastasis) at the time of enrollment. Participants with a history of a CNS metastasis
             previously treated with curative intent (for example, stereotactic radiation or
             surgery) that have not progressed on follow-up imaging, have been asymptomatic for at
             least 60 days and are not receiving systemic corticosteroids and or/anticonvulsants,
             are eligible. Participants with signs or symptoms of neurological compromise should
             have appropriate radiographic imaging performed before enrollment to rule out brain
             metastasis.

          -  Have received prior treatment with doxorubicin, epirubicin, idarubicin, and/or other
             anthracyclines or anthracenediones; the participant has received treatment with
             olaratumab or has participated in a prior olaratumab trial.

          -  For radiotherapy addendum only: Have received previous radiotherapy in the primary
             tumor lesion and/or prior treatment with olaratumab or has participated in a prior
             olaratumab trial.
      