Esophagectomy and reconstruction remain the standard procedure in the curative intent treatment for patients with resectable esophageal cancer. In attempts to reduce the complications’ morbidity and mortality of open esophagectomy, MIE has been widely used worldwide in recent years. Some prospective and meta-analysis studies have showed the potential short-term benefits of MIE, including less blood loss, lower incidence of respiratory complications, shorter hospital or ICU stays, and faster surgical recovery[13, 15, 16, 17]. Currently, McKeown with cervical esophagogastric anastomosis and lvor Lewis with thoracic esophagogastric anastomosis surgery were the most common surgical procedures in esophagectomy. Several studies have showed that MIE-McKeown procedure was associated with higher incidence of recurrent laryngeal nerve injury, pneumonia and anastomotic leakage than lvor-Lewis[18, 19, 20, 21]. However, MIE-McKeown also has some potential benefits, such as more proximal resection margin and more lymph nodes dissected, which seems to improve long-term survival[22, 23]. Thus, the MIE-McKeown procedure combined three-field lympadenectomy is recommended as a routine approach in China and Japan[7, 23, 24]. At present, approximately 700 patients with esophageal cancer underwent MIE-McKeown at our institution per year. This study included 1023 consecutive cases undergoing MIE-McKeown procedure, representing a single center large sample study, suggesting that the MIE-McKeown is feasible and can be safely performed with a 30-day mortality rate of 0.3%, a mean ICU stay of 1.3 days, and a median postoperative hospital stay of 12 days. In term of main postoperative complications, anastomotic leakage rate was 7.7%, pulmonary complication rate 13.4%, chyle leakge rate 2.3% and recurrent laryngeal nerve (RLN) injury rate 8.8%. These short-term outcomes of the procedure at our institution are equivalent to or superior to most published literatures[21, 25, 26, 27, 28].
According to our experience, prevention is key to the treatment of complications. Bleeding is known to be a common cause of unplanned surgical exploration after esophagectomy, accounting for 40% (4/10) of all secondary operation in our study. Hemorrhages and incision bleeding can be effectively prevented by careful examinations. In addition, chyle leakage is another common complication in open esophagectomy or MIE, causing unplanned surgical exploration. The previously reported incidence varies from 0.8–5.9%[25, 29] and 2.3% in our study. At present, the effectiveness of prophylactic thoracic duct ligation on preventing chylothorax still remains controversial[29, 30]. Moreover, the potential impact of thoracic duct ligation on long-term survival has not been determined. According to our experience, routine thoracic duct ligation was recommended for middle or upper esophageal cancer with T3-T4, and should be performed when thoracic duct was damaged definitely or suspiciously. In addition, several studies found that preoperative oral administration of olive oil can effectively pevent chylothorax[31, 32].
Anastomotic leakage after esophagectomy is one of the most severe complications. Some studies have shown that the incidence of neck anastomosis in Mckeown surgery is higher than that in Ivor Lewis surgery with intrathoracic anastomosis[18, 19, 20]. The reported incidence varies from 5–23.3% [15, 18, 21, 25, 27, 33] and 7.7% in our study. Tracheal fistula, one of the most fatal complications, accounting for 33.3% (1/3) of all deaths within 30 days after surgery in our study, was often caused by gastric acid or other pollutant secretions from anastomotic leakage. A large sample review, including 25 articles, gave evidence that anemia, increased amount of blood loss, low pH and high PCO2 values, prolonged surgery time and poor technique independently increased the risk of anastomotic leakage[34]. Therefore, some measures, such as gsatroprotection of blood supply, improvement of anastomotic technique, perioperative nutrition support and relieving the tension of anastomosis, can effectively reduce the incidence of the complications[34, 35, 36].
Besides anastomotic leak, pneumonia was the most observed complication following MIE. Previous studies showed that its incidence ranged from 9.0–31.9%, and was 13.4% in our study. Most of these cases were cured by conservative treatment and with 1 case died of aspiration pneumonia,which caused by recurrent laryngeal nerve (RLN) injury. Notably, RLN injury can be caused by contusions, excessive stretching and thermal damage occurring when dissecting the lymph nodes surrounding the left and right RLN[38]. So, it is essential to protect RLN from burning or shearing during manipulation.
Considering the high incidence of lymphatic metastasis surrounding RLN[39], we must dissect the lymph nodes in these fields. However, the meticulous dissection in a narrow space is still challenging and frequently leads to RLN palsy[38]. As operative experience increased, the rate of hoarseness in our center gradually decreased by avoiding stretching, compression and thermal injury on the RLN. Regarding the left RLN prevention, it is critical to clearly expose the RLN bluntly before lymph node dissection. In order to obtain an optimal visualization, we used some methods, such as the single lumen intubation, turn lateral decubitus position to semi prone position, assistant’ pull force from opposite side, which were conducive to dissect the left RLN easily[40].
The potential benefits of MIE-McKeown are a more proximal resection margin and improved lymph node dissection, which can provide more accurate pathological staging and improve patient survival, especially for patients with middle or upper thoracic esophageal cancer[7, 22, 23]. However, several prospective and observed studies showed that MIE-McKeown with three-filed lymphadenectomy has not prolonged the survival time than open procedure or MIE lvor-Lewis, and even though yielded more lymph nodes[41, 42, 43, 44]. In our study, 55.9% of cases were in stage of T3-T4, 38.7% with nodal positive (N1-3), and 34.2% with locally advanced esophageal carcinoma (IIIB་IVA stage). Our results showed that MIE-McKeown provided a high percentage of R0 radical resections (96.0%), adequate lymphadenectomy (the mean number of lymph nodes dissected 19.09, the mean number of lymph node stations 6.63), and obtained a 65.1% of 3-year OS and 52.7% of 5-year OS in squamous cell carcinoma, which was equivalent or superior to that reported for open esophagectomy or MIE Lvor-Lewis[12, 14, 23, 27, 28, 34, 36]. These results indicated that MIE McKeown method satisfied the oncological requirements and did not impact long-term survival rates. In addition, neoadjuvant chemotherapy seemd to offer 5-year survival advantage in advanced stage patients(for stage III: 53.1% vs. 32.9%, and for stage IV: 20.3% vs. 7.1%).
However, this clinical research has a number of limitations. First, this trial was a single central retrospective study lacking of control group to compare the surgical outcomes. Second, data on quality of life, functional results and cost-effectiveness have not been studied. Third, in this study, neoadjuvant therapy followed by esophagectomy for locally advanced ESCC seemed to improve long-term survival compared with surgery alone, but we did not conduct a rigorous design to confirm the survival advantage. Lastly, although the sample size is large in this study, multicenter randomized controlled trials (RCTs) should be conducted in the future work to verify the equivalency or advantages of MIE-Mckeown compared with open esophagectomy or MIE-Lvor Lewis.