Overall morbidity after total minimally invasive keyhole oesophagectomy versus hybrid oesophagectomy (the MICkey trial): study protocol for a multicentre randomized controlled trial

Background: Oesophageal cancer (EC) is the sixth leading cause of cancer death worldwide. Oesophageal resection is the only curative treatment option for EC which is frequently performed via an abdominal and right thoracic approach (Ivor-Lewis operation). This 2-cavity operation is associated with a high risk of major complications. To reduce postoperative morbidity, several minimally invasive techniques have been developed that can be broadly classified into either hybrid oesophagectomy (HYBRID-E) via laparoscopic/robotic abdominal and open thoracic surgery or total minimally invasive oesophagectomy (MIN-E). Both, HYBIRD-E and MIN-E, compare favourable to open oesophagectomy. However, there is still an evidence gap comparing HYBRID-E with MIN-E with regard to postoperative morbidity. Methods: The MICkey trial is a multicentre randomized controlled superiority trial with two parallel study groups. A total of 152 patients with oesophageal cancer scheduled for elective oesophagectomy will be randomly assigned 1:1 to the control group (HYBRID-E) or to the intervention group (MIN-E). The primary endpoint will be overall postoperative morbidity assessed via the comprehensive complication index (CCI) within 30 days after surgery. Specific perioperative parameters, as well as patient-reported and oncological outcomes, will be analysed as secondary outcomes. Discussion: The MICkey trial will address the yet unanswered question whether the total minimally invasive oesophagectomy (MIN-E) is superior to the HYBRID-E procedure regarding overall postoperative morbidity. Trial registration: DRKS00027927 U1111-1277-0214.