Fifty patients treated at our facility for cancer of the prostate, lung, H&N, liver, or pancreas (n = 10 each) from April 2010 to November 2015 were randomly selected for retrospective analysis. Each pair of orthogonal images at completion of patient positioning on 1 day during the treatment period was retrospectively analyzed. This study was approved by the Institutional Review Board at our hospital (approval number: 15‐109); all data were anonymized. Orthogonal DRs after patient positioning, treatment planning data, and CT images were evaluated.