A multicenter randomized controlled trial of surgery alone or surgery with atrial natriuretic peptide in lung cancer surgery: Study protocol for a randomized controlled trial

Background: Postoperative cancer recurrence is a major problem following curative surgery. In a previous retrospective study of lung cancer surgery, we reported that administration of atrial natriuretic peptide (ANP) during the perioperative period reduced postoperative recurrence. We demonstrated that ANP inhibited the adhesion of cancer cells to vascular endothelium as a vasoprotective action. The objective of this study is to evaluate the effects of ANP on the incidence of postoperative cancer recurrence in lung cancer surgery. Methods/design: The present study is a multicenter, randomized trial with two parallel groups of patients with lung cancer comparing surgery alone and surgery with ANP administration for 3 days during the perioperative period. A total of 500 patients will be enrolled from 10 Japanese institutions. The primary endpoint is 2-year relapse-free survival (RFS). The secondary endpoints are 2-year cancer-specific RFS, 5-year RFS, overall survival, the incidence of postoperative complications, and the completion rate of ANP treatment. Discussion: The principal question addressed in this trial is whether ANP with its vasoprotective action can reduce cancer recurrence following lung cancer surgery. Trial registration: UMIN Clinical Trials Registry identifier: UMIN000018480. Registered on 31 July 2015.