To the Editor We read with great interest the article by Guo et al,1 on combining surgery with extensive intraoperative peritoneal lavage (EIPL) for patients with advanced gastric cancer. This study is important because peritoneal recurrence carries a very poor prognosis with no cure. We are currently conducting a randomized clinical trial on this topic with a similar design in which the primary end point is 3-year overall survival.2 In the Guo et al1 article, the authors reported the short-term outcomes of their trial and found that the EIPL group had less postoperative complications, ileus, and wound pain; hence, they concluded that EIPL increases the safety of surgery. However, because the trial was powered to detect an absolute difference in 3-year overall survival of 11%, which is their primary end point, we wondered whether their observed findings might be owing to chance. We estimated that based on a 2-sided test of 5%, a sample size of between 800 to 1100 would be required to achieve an 80% power to detect the observed differences in the short-term outcomes of mortality, wound pain, and ileus as reported in the paper.3 Further, based on the reported sample size of 550, the trial has less than 65% power to detect significant differences at the 5% level for the outcomes concerned. Besides, several hypotheses were evaluated in this article without accounting for multiple testing.4 Had corrections been made for multiple testing, none of these findings would be significant. In addition, we suggest the authors report the American Society of Anesthesiologists classification status, the analgesics protocol, and indicate how ileus and their postoperative complications were defined in the article. We are of the opinion that this information has significant bearing on the interpretation of their conclusions.
Identify all potential conflicts of interest that might be relevant to your comment.
Conflicts of interest comprise financial interests, activities, and relationships within the past 3 years including but not limited to employment, affiliation, grants or funding, consultancies, honoraria or payment, speaker's bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued.
Err on the side of full disclosure.
If you have no conflicts of interest, check "No potential conflicts of interest" in the box below. The information will be posted with your response.
Not all submitted comments are published. Please see our commenting policy for details.
Tai B, Shabbir A, So J. Combination of Surgery With Extensive Intraoperative Peritoneal Lavage for Patients With Advanced Gastric Cancer. JAMA Surg. Published online August 14, 2019. doi:10.1001/jamasurg.2019.2658
Customize your JAMA Network experience by selecting one or more topics from the list below.
Create a personal account or sign in to: