Published Online: April 21, 2014. doi:10.1001/jamainternmed.2014.1001.
Study concept and design: All authors.
Acquisition, analysis, or interpretation of data: All authors.
Drafting of the manuscript: All authors.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Cheng.
Administrative, technical, or material support: Rodriguez, DeJesus.
Study supervision: Rodriguez.
Conflict of Interest Disclosures: None reported.
Previous Presentation: This study was presented as a poster at the Annual Meeting of the American Society of Clinical Oncology; May 31-June 4, 2013; Chicago, Illinois.