**3. Minimally invasive surgery**

Pulmonary complications after transthoracic esophagectomy are high. The minimally invasive thoracoscopic approach might result in lower morbidity and mortality rates. Being minimally invasive, thoracoscopy should replace the open approach. In a study conducted by Cuschieri et al. [35], the researchers performed right thoracoscopy (esophagectomy and lymph node dissection) in a small group of patients and paved the way for the future use of thoracoscopic esophagectomy. This procedure proved to be feasible and even superior to open surgery. Nevertheless, the first outcomes using this approach were not significantly better than those obtained with the open approach, mainly as a result of the great number of pulmonary complications [36–38]. However, a few medical research centers in Japan found a new stimulus. For example, Akaishi et al. [39] obtained good outcomes in 39 patients with cancer of the esophagus who underwent en bloc esophagectomy with radical lymph node dissection via right thoracoscopy, with the following parameters: 200±41 min operating time, 270±157 ml blood loss, and the number of harvested lymph nodes was 19.7±11. All patients survived and there was a modest decrease in vital capacity in 22 of them, without requiring postoperative ventilation. A significant finding of the study was that pulmonary complications were reduced compared with the open procedure.

In their study, Luketich et al. [40] proved that minimally invasive esophagectomy (MIE) is efficient and safe in the United States. The study was conducted on 1033 consecutive patients and results indicated a significantly lower mortality rate (0.9%), with an 8-day median hospital stay. In a study performed in the United Kingdom, Mamidanna et al. [41] assessed 7502 patients undergoing esophagectomy (E) and MIE (n = 1.155) and results showed no differences in terms of 30-day morbidity and mortality. MIE proved to be safe for use by professionals, without supplementary patient safety risks. Despite the low number of annual esophagectomies (2) per medical center, study results were similar and MIE was preferred in terms of perioperative outcomes. On the other hand, there are insufficient and incomplete cancer comparative research data. Certain centers noted higher lymph node retrieval following MIE with lymph node dissection [42–44], whereas others did not find any considerable differences [45]. In a study performed on 168 patients, Palazzo et al. [46] demonstrated that long-term survival was twice better in patients who underwent MIE (hazard ratio—2.0). Despite significant patient and tumor variables, there were concerns related to the ability to reproduce the major differences in results obtained for these groups. Additionally, the small number of patients might assign any variations to defective regulations.

Long-term survival rates following open esophagectomy do not differ significantly when comparing these surgical procedures, as shown by various meta-analyses and randomized trials [28]. In their study, Tabira et al. [29] recommended the use of three-field lymph node dissection in patients with one to four lymph node metastases. As indicated by Shiozaki et al. [30], neck dissection might be eliminated in patients with carcinoma in the middle or lower third of the esophagus without lymph node metastasis along the recurrent nerve chain. Lerut et al. [31] also proved an improvement in patient survival following three-field lymph node dissection.

When comparing three-field with two-field lymph node dissection for squamous cell carcinoma of the esophagus, Kato et al. obtained 5-year survival rates of 48.7% for the first approach and 33.7% for the second. However, this study was contested due to differences in patient characteristics. Isono et al. [32] conducted a nationwide study and obtained better survival rates when using three-field dissection instead of the two-field approach. Fujita et al. [33] also presented much better survival rates following three-field lymph node dissection (p < 0.05) for carcinoma in the upper or middle third of the esophagus spreading to the lymph nodes. Still, there were no differences in mortality, morbidity, and postoperative quality of life between the two approaches [33]. Radical esophagectomy helps remove ≥80 lymph nodes

Pulmonary complications after transthoracic esophagectomy are high. The minimally invasive thoracoscopic approach might result in lower morbidity and mortality rates. Being minimally invasive, thoracoscopy should replace the open approach. In a study conducted by Cuschieri et al. [35], the researchers performed right thoracoscopy (esophagectomy and lymph node dissection) in a small group of patients and paved the way for the future use of thoracoscopic esophagectomy. This procedure proved to be feasible and even superior to open surgery. Nevertheless, the first outcomes using this approach were not significantly better than those obtained with the open approach, mainly as a result of the great number of pulmonary complications [36–38]. However, a few medical research centers in Japan found a new stimulus. For example, Akaishi et al. [39] obtained good outcomes in 39 patients with cancer of the esophagus who underwent en bloc esophagectomy with radical lymph node dissection via right thoracoscopy, with the following parameters: 200±41 min operating time, 270±157 ml blood loss, and the number of harvested lymph nodes was 19.7±11. All patients survived and there was a modest decrease in vital capacity in 22 of them, without requiring postoperative ventilation. A significant finding of the study was that pulmonary complica-

In their study, Luketich et al. [40] proved that minimally invasive esophagectomy (MIE) is efficient and safe in the United States. The study was conducted on 1033 consecutive patients and results indicated a significantly lower mortality rate (0.9%), with an 8-day median hospital stay. In a study performed in the United Kingdom, Mamidanna et al. [41] assessed 7502 patients undergoing esophagectomy (E) and MIE (n = 1.155) and results showed no differences in terms of 30-day morbidity and mortality. MIE proved to be safe for use by professionals,

and 5-year survival rates are around 40–60% [34].

tions were reduced compared with the open procedure.

**3. Minimally invasive surgery**

24 Esophageal Abnormalities

In a study assessing three-field lymph node dissection, Osugi et al. compared 77 patients with squamous cell cancer who underwent minithoracotomy to 72 controls who underwent conventional three-stage treatment. Exceptional outcomes were obtained in terms of lymph node retrieval (33 vs. 32), operating time (227 vs. 186 min), reduced vital capacity (15% vs. 22%, p = 0.016), 3-year survival (70% vs. 60%), and 5-year survival (55% vs. 57%) [44]. Resection via thoracoscopy showed almost similar results to open esophagectomy. Moreover, surgical trauma was reduced. The differences in outcome between the first 34 and the next 46 patients who underwent surgery in the same study group demonstrated the impact of the learning curve on obtaining shorter operating times and better results by using this approach. Other advantage is that greater experience helps reduce postoperative pulmonary complications (5% incidence). Reduced blood loss, shorter operating time for thoracoscopy, reduced postoperative respiratory complications and higher lymph node retrieval were all observed in the last group [44]. In a study conducted on 222 patients undergoing thoracoscopic and laparoscopic esophageal resection, Luketich et al. (Ann Surg 2003; 238:486–494) showed an incidence rate of pneumonia of 7.7%. A significant finding was the reduced length of intensive care unit stay (1 day) and hospital stay (7 days) and the 1.4% operative mortality. Quality of life indicator was comparable to baseline scores and population standards. Nguyen et al. [47] assessed 46 consecutive patients and found similar results to Luketich et al. There have also been studies supporting robot-assisted thoracoscopy; however, there is still need for further investigation regarding robotic esophagectomy [48].

The results obtained by Biere et al. [49] in the TIME (Traditional Invasive vs. Minimally Invasive Esophagectomy) trial comparing the outcomes of 115 British patients who underwent either E or MIE showed that besides a decrease in perioperative pulmonary complications, the two procedures were more or less similar. However, the main competence of the trial was to show differences in short-term outcomes, with lower capacity in pointing out other outcomes. Patient outcomes were adapted to a population, improving the ability to perform a multivariate analysis of small differences in survival. There are few data on comparative differences in robotassisted esophagectomy. In a study conducted on 43 patients who were treated with MIE (of which 11 underwent robot-assisted esophagectomy), Weksler et al. [50] reached the conclusion that robot-assisted and conventional procedures were similar. There were not enough patients included in the study, the results were disorganized, and there were no cancer data. Our study also experiences difficulties due to this aspect when comparing robotic with conventional MIE, but we managed to explain certain confounding variables for our outcomes. The limitations of our study are represented by the inability to determine specific MIE approaches (the McKeown procedure, the Ivor Lewis approach, and the transhiatal procedure). Earlier studies have demonstrated that the three procedures have similar outcomes, even though there are differences in terms of perioperative complications [51]. Another drawback was the difficulty in differentiating between patients who underwent hybrid procedures, such as laparoscopy combined with minithoracotomy, and patients who were treated with total MIE. These limitations pave the way for the occurrence of unknown interactions and confounding variables. Currently, there are two different clinical trials comparing E to MIE patients, namely the French MIRO trial [52] and the British ROMIRO trail [53]. Still, the study that we conducted is the most extensive comparative effectiveness research of MIE assessing long-term survival. As a result, MIE determines poor improvement in perioperative outcomes, with no negative impact on survival rates.
