Limitations of Preoperative Clinical Staging in Selecting the Enrolled Patients Before Randomization
We read Chang et al's study with great interest.1 According to this randomized controlled trial, the adding of intraportal chemotherapy is associated with reduced systemic recurrence, especially in the stage III colon cancer group. Nevertheless, there is some concern about the study design. In this study, patient enrollment and randomization were based on the preoperative staging and intraoperative surgical findings. However, the accuracy of evaluating T and N staging using preoperative computed tomography in the general population is known to be 60% to 80%.2 Thus, it is very difficult to exactly predict the patient's final pathologic stage before surgical resection. In this study, all enrolled patients were proved to be pathologic stage II or stage III. We are concerned that it would be very difficult to exclude stage I colon cancer patients by a preoperative imaging study. How the authors eliminate these inherent difficulties of randomization is questionable.