A revamped MIC-McKeown operation without removing azygos vein arch, bronchial artery and vagus nerve trunk

Radical resection of esophageal cancer is the preferred method for early and middle esophageal cancer. Traditional radical surgery for esophageal cancer is mostly anatomic esophagectomy, systematic lymph node dissection, and tubular gastroesophageal anastomosis. Those operations bring about large surgical trauma, involving a wide area of functional damage. Clinically, sequelae like huge thoracic, gastric and gastrointestinal dysfunction are prevalent, affecting postoperative rehabilitation and quality of life of patients [1, 2]. With the deepening of the understanding of esophageal cancer, the continuous innovation of minimally invasive surgical techniques for esophageal cancer, the improvement of medical instruments, and the clinical application of energy and high-definition video-assisted thoracoscopy and other working platforms, minimally invasive surgical treatment of esophageal cancer has been continuously promoted, gradually changing from the original anatomical surgical approach to the functional surgical approach [3]. Under the premise of not violating the principle of radical tumor treatment, it is the common interest pursuit of clinical workers and patients to protect the function of the non-target resection area around the esophagus more, thus improving the quality of life of postoperative patients [4]. After many attempts by previous clinical workers, it is found that the preservation of bronchial artery and vagus nerve trunk often leads to good results, but there are few reports on preservation of azygos vein arch, bronchial artery and vagus nerve trunk [5, 6]. This article summarized the merits of revamped mic-Mckeown operation and explored the safety, feasibility and effectiveness of this operation in clinical practice.

Two of the 13 patients were male, with an average age of 70.92 ± 7.70 years; Clinical stage I: 6 cases, stage II: 7 cases, middle esophagus: 12 cases, lower esophagus: 1 case. Preoperative clinical data of patients were detailed in Table 1.

All the 13 patients successfully completed operation. The number of intraoperative lymph node dissection, operation time, blood loss, postoperative thoracic fluid drainage, postoperative ICU stay time, postoperative anal exhaust, postoperative feeding time, postoperative pathological stages and complications were shown in Table 2.

Results of the maximum diameter of chest and stomach, V-VT test, gastrointestinal symptoms and 30 ml water test 1 month after the operation of 13 patients on the 7th day after the operation were shown in Table 3.

The prerequisite of functional surgery for esophageal cancer is not to put away the tumor R0 rate and to violate the principle of radical treatment [10, 11]. In lights of this condition, all the cases mentioned in this paper were selected as ct1-2N0M0 malignant tumors of the lower and middle thoracic segment at the level of azygos venous arch in clinical stages. There were abundant reticular lymphatic vessels in the submucosa of the esophagus. With the escalation of tumor T stage, the infiltration depth deepened, and the reticular lymphatic network was involved. Tumor cells metastasized through the lymphatic network, and the most frequent site of metastasis was the para-laryngeal nerve region [12, 13]. Therefore, enhanced chest CT scan combined with ultrasound gastroscopy was required for all the enrolled patients, and the tumor was assessed to be confined to T2 and located in the lower and middle thoracic segment without regional lymph node metastasis. Among the 13 patients enrolled in this study, postoperative pathology confirmed negative margins, among which 5 patients showed POSTOPERATIVE N + , and adjuvant chemotherapy or chemoradiotherapy was recommended for all patients [14].

If the vagus nerve trunk and its main branches were to be preserved, it is necessary for the operating personnel to get familiar with the thoracoabdominal anatomy of the vagus nerve trunk and its main branches: The left vagus nerve continues to the anterior vagus trunk in the lower esophagus, and divides into the anterior gastric and hepatic branches near the cardia. The right vagus nerve forms the posterior trunk of the vagus nerve at the rear of the lower esophagus, and gives out the posterior gastric branch near the cardia. It goes along the back of the lesser curvature of the stomach, and branches distribute in the posterior wall of the stomach. The abdominal branch of the vagus nerve is the final branch of the posterior trunk of the vagus nerve. It is lasted until right to the vicinity of the abdominal trunk and mixes with the sympathetic nerve to form the abdominal plexus. Along with the blood vessels, it distributes in the abdominal digestive tract above the left curvature of the liver, bile, pancreas, spleen, kidney and colon [15, 16]. The vagus nerve trunk and lower thoracic esophageal plexus, abdominal and liver branches are usually retained. On the basis of the principle of radical surgical treatment and duo to the limitations of surgical techniques, only the thicker branches of anterior and posterior vagus plexus are the only sections could be reserved. In this group, only the right vagus nerve trunk was successfully preserved in 2 cases, and the liver branch was injured in 3 cases, which was related to the unskilled operation and large variation of neuroanatomy. In thoracic surgery, it is suggested to dissect the bilateral vagus nerve trunk under the azygos vein arch and then dissociate it downward after being marked with non-invasive strips, so as to better protect the integrity of the main vagus nerve. In abdominal surgery, it is recommended to open the peritoneum, find the mark of vagus nerve skin that was originally placed in the chest, and then pull it into the abdominal cavity before dissociating the stomach, so as to better expose and protect the liver and abdominal branches.

Minimally invasive McKeown and tubular stomach are the conventional means for digestive tract reconstruction. Postoperative thoracic stomach will impinge on cardiopulmonary function and gastrointestinal dysfunction, and reduce the life quality of patients. In previous studies, in order to reduce this complication, different studies have discussed the placement of the tubular stomach (retrosternal path, trans-mediastinal esophageal para-bed path) and the size of the tubular stomach, with different results [17, 18]. In this study, the azygos venous arch was retained through the mediastinal esophagus beside the bed. Mechanically, the two ends of azygos venous arch were equivalent to two sets of screw fixation principle. The arch was a cantilever beam structure, and the tubular stomach was embedded under the azygos venous arch of the esophagus bed, which was equivalent to two sets of screws fixing the cantilever beam structure to fix the tubular stomach in the esophagus bed; while the azygous vein arch is fully free and itself is a soft lumen structure, which expands during feeding in the tubular stomach to avoid mechanical obstruction, as shown in Fig. 2. On the 7th day after operation, the tubular stomach was fixed in the esophageal bed without obvious chest and stomach dilation, which met the physiological requirements.

Gastrointestinal dysfunction is a common postoperative complication of esophageal cancer. At present, it is thought that gastrointestinal dysfunction is related to vagus nerve injury and function limitation, or early sympathetic nerve excitation. After vagus nerve trunk was cut off, the small intestine to promote power hormone secretion declined, at the same time gastric peristalsis lost inhibiting ectopic pacemaker, making the gastric antrum and duodenum peristaltic wave separation pressure, continuity of the gastrointestinal peristalsis wave disturbance, stomach food retention phase extension and emptying delay, cause gastric emptying disorder, or pyloric sphincter is out of control, and cause emptying too fast, cause diarrhea [19]. Among the 13 patients involved in the study, abdominal distention and diarrhea occurred in 1 case within 1 month after surgery, and the symptoms did not need drug intervention, reflecting the preservation of vagus nerve, which plays a promoting role in postoperative gastrointestinal function recovery and can better prevent gastrointestinal dysfunction.

Under revamped Mic-McKeown operation, the bronchial artery, the main vagus nerve trunk, has been preserved; moreover, under the premise of ensuring the principle of oncology treatment, the operation time and blood loss were not increased, the integrity of azygos venous arch of vagus nerve and bronchial artery was better preserved, and postoperative mechanical obstruction of pleural stomach, huge pleural stomach and gastrointestinal dysfunction was not occurred, which was more in line with physiological requirements.