title: Reply to T.A. Yap et al.
authors.affiliation: University of Chicago, Chicago, IL.
authors.forename: Randy F
authors.initials: RF
authors.lastname: Sweis
authors.affiliation: University of Chicago, Chicago, IL mratain@medicine.bsd.uchicago.edu.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Ratain
mesh_terms: D014408:Biomarkers, Tumor; D001706:Biopsy; D017321:Clinical Trials, Phase I as Topic; D006801:Humans
chemical_list: D014408:Biomarkers, Tumor