Application of single-port video-assisted thoracoscope in treating thoracic oesophageal squamous cell carcinoma using McKeown approach.

OBJECTIVE: This study aims to investigate the feasibility of single-port video-assisted thoracoscope (SPVATS) in treating thoracic oesophageal squamous cell carcinoma (TESCC) using McKeown approach.
MATERIALS AND METHODS: Totally 10 McKeown approach-based SPVATS surgeries (8 males and 2 females, aged 42-68 years) were carried out from January 2015 to December 2015 to treat TESCC, including one case in upper thoracic segment, 5 cases in median thoracic segment and 4 cases in inferior thoracic segment. All the cases were pathologically diagnosed as SCC pre-operatively. SPVATS was performed to free thoracic oesophagus and dissect the lymph nodes, and laparoscopy was performed to free stomach and to perform oesophagus-left gastric collum anastomosis.
RESULTS: All the patients were successfully completed SPVATS, with average thoracic surgery time as 150 min, intra-operative blood loss as 30-260 ml (average 90 ml), and post-operative hospital stay as 9-16 days (average 12 days).
CONCLUSIONS: SPVATS was technically feasible and safe in treating TESCC using McKeown approach, with less trauma and rapid post-operative recovery, and hence, it could be used as a new surgical option for McKeown approach-based TESCC treatment.

INTRODUCTION

Early radical resections are the main treatment methods towards oesophageal squamous cell carcinoma (ESCC). Classic transthoracic oesophagectomy (McKeown approach) could resect oesophagus lesion as a whole piece, and hence, the surgical results could be satisfactory and the regional lymph node dissection could be clean. With the maturation of video-assisted thoracoscope in thoracic surgeries,[1] good vision, subtle operating system and mature operating technologies have made the multi-portal thoracoscopic minimally invasive laparoscopic oesophageal resection more and more mature. Meanwhile, single-port video-assisted thoracoscope (SPVATS) gradually appeared, which was first used in simple thoracic surgeries,[2] and further applied to lung[3] and mediastinal tumour resection;[4] relevant summaries have been reported,[5] and the feasibility of SPVATS for standard mediastinal lymph node dissection was also further verified.[6] The application of SPVATS towards thoracic ESCC (TESCC) has also been gradually carried out.[7]

Would minimally invasive oesophagectomy be safe?[8] Whether SPVATS could be used in the McKeown approach for TESCC? Whether SPVATS could safely resect oesophagus, and perform standard dissection towards local oesophageal region and mediastinal lymph nodes, as well as avoid damaging the surrounding organs and tissues? Some scholars had compared SPVATS and multi-portal VATS (MPVATS) in treating medio-inferior TESCC.[9]

The treatment effects of conventional VATS towards thoracic oesophageal cancer have been gradually affirmed. With the application of HD thoracoscopy, as well as the maturation of fine operating systems and techniques, intra-operative blood loss has been further reduced, intra-operative anatomic and surgical fields have been made much more clear, and surgical safety and radical treatment have been further improved. SPVATS has the same vision field as conventional VATS, and the vision field of the entire surgical team could be better than conventional direct-vision surgeries. With proper pre-operative patient selection, the application of conventional multi-portal thoracoscopy for SPVATS in treating TESCC using McKeown approach would be safe, effective and standardised. Its less trauma, its post-operative complications are less than traditional thoracotomies, and patients recovery would be faster.[10] It might allow more benefits towards the patients.

ESCC is a common malignant tumour of the digestive system, and patients’ age at onset are normally over 40 years. Due to special oesophageal anatomical positions, which is in a small region among the spine, aorta and hilum of lung. Compared with MPVATS, SPVATS generates smaller surgical incisions, its post-operative complications are less than traditional thoracotomies, and patients recovery would be faster. 10 McKeown approach-based SPVATS surgeries were carried out from January 2015 to December 2015 in People's Hospital of Jieyang Guangdong Province, to treat TESCC, and achieved good results. It is reported below.

MATERIALS AND METHODS

Clinical data

The ten patients included 8 males and 2 females, aged 42–68 years, including one case in upper thoracic segment, 5 cases in median thoracic segment, and 4 cases in inferior thoracic segment. All the patients were performed pre-operative endoscopy and diagnosed as SCC. Routine pre-operative neck, chest and upper abdominal computed tomography (CT) examinations confirmed the tumour invasion degrees, and the conditions at the neck, mediastinal lymph nodes and para-lymph nodes of left gastric arteries. All the patients had the tumour length ≤3 cm, without obvious outwards invasion as well as no significantly enlarged lymph node at the neck, in the mediastinum, and beside the left gastric arteries. This study was conducted in accordance with the Declaration of Helsinki. This study was conducted with approval from the Ethics Committee of People's Hospital of Jieyang Guangdong Province. Written informed consent was obtained from all participants.

Surgical methods

Dual-lumen endotracheal intubation was first performed to ensure left lung ventilation during thoracoscopic operations, which was then transferred to dual-lung ventilation during laparoscopy and neck operations. The surgical procedures were divided into three steps: (1) thoracoscopic operations: The patient was place in the left lateral position and asked to lean forward 30°. The surgeon stood in front of the patient. One 3.5–5 cm intercostal incision was then made at the 5th rib of right midaxillary line to enter the chest, and the incision protective sleeve should be placed simultaneously (Beijing Aerospace Kady Technology Development Institute); the thoracoscope was then placed. After that, the possibility of endoscopic tumour resection should be made clear first, followed by thoracic oesophagectomy + paraoesophageal and mediastinal lymph node dissection. Processes: The arch of azygos vein was first freed, ligated, and cut-off. One electric coagulation hook or ultrasonic knife was then used to longitudinally incise the mediastinal pleura, with obvious vessels cut by the ultrasonic knife; continuously, the electric coagulation hook or ultrasonic knife freed the oesophagus upwards and downwards along the oesophageal venter and dissected the paraoesophageal lymph nodes. The upper site should be separated until the thoracic inlet, and the lower site should reach the oesophageal hiatus, which were then removed after cutting; the mediastinal lymph nodes were then dissected [Figure 1]. The thoracic ducts were then selectively ligated, during which period the thoracoscope holder stood by the patient's head for processing the superior and middle thoracic oesophagus. When dealing with the lower thoracic oesophagus, the thoracoscope holder stood by the patient's foot. During sweeping para-left recurrent laryngeal nerve, carina and superior phrenic lymph nodes, the 5th intercostal space of the triangle of auscultation and the 7th intercostal space of the infrascapular line were implanted 2-mm thread-leading device (Hangzhou Kangji Medical Instrument Co., Ltd.), respectively, to drag the silk connecting the oesophageal sling outwards until outside the skin to help stretch the oesophagus [Figure 2] so as to facilitate the exposure; the dissection was then completed. After the chest surgery, intrathoracic drain tubes were conventionally placed at the rear edge of the incision, and the chest incision was then sutured. (2) laparoscopic operations: After turned the patient into the supine position, the neck and abdomen were then paved the disinfection towels, and the patient was then changed to 30° reverse Trendelenburg position; 1-mm incision was then prepared below the belly button, and the veress needle was then placed to establish artificial pneumoperitoneum; one 12-mm in diameter Trocar trocar (Hangzhou Kangji Medical Instrument Co., Ltd.) and the laparoscope were then placed; under direct vision, 4 Trocar trocar (5, 5, 5 and 12 mm, Hangzhou Kangji Medical Instrument Co., Ltd.) were then placed into the midclavicular lines of the inferior border of right and left costal arches and the anterior axillary line, respectively, as the operation holes; the surgeon stood on the left side of the patient at this time checking the conditions of adhesion and metastasis of other organs within the abdominal cavity. The greater gastric curvature was then freed along the lateral side of the vessel arch of greater gastric curvature, followed by separating and ligating the left gastric artery and vein; the ultrasonic knife was then used to clean the left gastric artery and vein, common hepatic artery, left splenic vein, paracardial lymph nodes, and the freeing was kept upwards until the oesophageal hiatus and met with the thoracic free oesophagus. (3) oesophagogastrostomy: One 5-cm incision was first made along the leading edge of the left sternocleidomastoid, which was then freed until the cervical oesophagus along the median side of the carotid artery sheath; another 5-cm incision was made subxiphoidly in the upper abdomen to pull the stomach out to prepare the tubular stomach and lift it to the neck. One circular anastomat was then used to for the anastomosis of gastric bottom and cervical oesophagus. Pre-operative incision localisation, intraoperative incision protective sleeve, post-operative chest, abdomen, and neck suture conditions are shown in Figure 3.

Figure 1

Freeing oesophagus, and sweeping lymph nodes of left and right para-recurrent laryngeal nerve

Figure 2

Two millimetres thread-leading device helped to stretch the oesophagus outside the skin

Figure 3

Conditions of pre-operative, intra-operative, and post-operative incision

RESULTS

The ten patients enrolled in this study were successfully completed the thoracic surgery, and no case was intraoperatively conversed to open surgery; no serious intra-operative and post-operative complication occurred, with mean chest operation time as 150 min, intra-operative blood loss as 30–260 ml (average 90 ml), post-operative extubation time of thoracic drainage tube as 3–5 days, post-operative hospital stay as 9–16 days (average 12 days). No post-operative pulmonary infection or chylothorax occurred, and no significant chest incision pain occurred post-operatively. According to the pain degree of the WHO: 3 case of degree 0 and 7 cases of degree I. One case occurred small amount of anastomotic leak on the 7th day, but was cured by re-dressing and discharged on the 16th day.

Post-operative pathological staging used the TNM staging criteria of UICC (7th edition). p-TNM staging: 1 case of Stage I, 3 cases of Stage II and 6 cases of Stage III. Pathological grading: 1 case of G1, 2 cases of G2 and 7 cases of G3; all the patients were performed oesophageal resection and systematic lymph node dissection. A total of 256 lymph nodes were dissected, with an average as (20.39 ± 8.05), and 35 metastatic lymph nodes were dissected, with an average as (3.52 ± 0.83). A total of 156 mediastinal lymph nodes were dissected, including 75 superior mediastinal lymph nodes (19 metastatic lymph nodes, metastatic rate 25.33%) and 81inferior mediastinal lymph nodes (21 metastatic lymph nodes, metastatic rate 25.93%).

DISCUSSION

In the past 20 years, thorascopic surgeries have been increasingly used in oesophageal cancers and maturate gradually. With its characteristics of minimal invasion, the surgical injuries could be reduced to the lowest level while the clinical results of open surgery could also be achieved, and it also shows particular advantages in mediastinal lymph node dissection. At the same time, it could also accelerate patients’ post-operative recovery.[1112] Palanivelu et al.[13] summarized the experience of 130 thoracoscopic resection cases of oesophageal cancer, and found that after certain training, skilled surgeons could proficiently carry out laparoscopic surgeries and achieve the clinical effects of open surgery; furthermore, the perioperative mortality, hospital stay, and incidence of respiratory complications could be lower than open surgery. Oesophageal carcinectomy performed with SPVATS was designed to uphold the concept of minimally invasive surgery, reduce chest incision, and use the careful observation field of the laparoscope, thus further reducing patients’ trauma and completing surgeries with higher qualities.

The patients enrolled in this study included 1 case of upper thoracic oesophageal carcinoma, 5 cases of median thoracic oesophageal carcinoma and 4 cases of inferior thoracic oesophageal carcinoma. This study selected the cases with tumour length <3 cm, and pre-operative neck, chest and upper abdominal CT examinations showed no obvious tumour invasion, and no significant enlarged lymph node beside the neck, mediastinum and left gastric artery. The post-operative analysis revealed that among T1, T2 and T3, cases with inferior oesophageal cancer had relatively easier surgical operations, but those with anterior oesophageal cancer in T3 had relatively difficult surgical operations. However, by implanting one 2-mm thread-leading device at the 5th intercostal space of the triangle of auscultation, the thread connecting the oesophageal sling was then dragged outside the skin so as to help stretch the oesophagus, so the oesophagus could obtain satisfactory exposure effects and safe freeing, which was also conducive to complete the lymph node dissection beside the left recurrent laryngeal nerve. The implantation of another 2-mm thread-leading device under the 7th intercostal space of the infrascapular line, as well as the thread connecting the oesophageal sling was dragged outside the skin to help stretch the oesophagus, satisfactorily exposed the median and inferior oesophageal segment, and was also conducive to complete the dissection of carina and superior phrenic lymph nodes. All the cases showed minor difficulty in the lymph node dissection beside the right recurrent laryngeal nerve. Under the premise of one-lung ventilation, the minimally invasive procedures of SPVATS were the same fine as MPVATS, and its intra-operative bleeding was less, the vision was clear, and its high-definition camera technology could much more clearly display important anatomical structures within the thorax. The long-arm operating lever could also be used for stable operations deep in one patient's body cavity with the aid of external support. The chest operations via SPVATS could meet the requirements of fully freeing the oesophagus from the chest top (upper level) down to the diaphragm (lower level); meanwhile, it could properly handle the nourishing blood vessels, as well as protect the surrounding organs and tissues. The thoracic aorta, thoracic duct, recurrent laryngeal nerve, and trachea membrane were all well protected in this study. The presence of superior mediastinal lymph node metastasis could be seen as a predictor of poor prognosis.[14] Among the superior mediastinal lymph nodes, lymph nodes beside the bilateral recurrent laryngeal nerves are the most common metastatic site of ESCC, and also the key part during the lymph node metastasis from the superior mediastinum to the neck.[15] Therefore, the importance of lymph node dissection in this region in surgically treating median TESCC could be seen. Fujita[7] reported that the intraoperative lymph node metastasis rate beside the right recurrent laryngeal nerve was the highest. Lymph node dissection is very important in the radical correction of oesophageal cancer, and it is also one of the symbols for the judgement of whether the cancer was radically cured.[16] Whether VATS could achieve standard lymphadenectomy? In the first few years, debates about this issue were more, but became fewer and fewer in recent years. Cadière et al.[17] reported that the combination of these two thoracoscopes could improve the quality of large-scale lymph node dissection. In this study, the numbers of patients’ anterior and inferior mediastinal lymph node dissection showed no significant difference with those dissected using MPVATS. SPVATS could also achieve the vision width of MPVATS, together with the advantages of no blind spot and less intra-operative blood loss. The vision during lymph node dissection was also clear, so it also could greatly improve the results of lymph node dissection.

Lung infection is one of the major complications after radical resection of oesophageal cancer, and clinical studies indicated the pulmonary infection rate in conventional thoracotomies was 10%–20%, and age, pulmonary functions, long-term smoking, post-operative severe pain, recurrent laryngeal nerve injuries and hypoalbuminemia were the risk factors of post-operative pulmonary infections.[18192021] The application of SPVATS in McKeown approach-based ESCC treatment could avoid large incisions in conventional thoracotomies, and also reduce the incisions made in MPVATS to one 3–5 cm incision, and hence, the integrity of the chest wall could be better preserved, resulting in significantly reduced post-operative pain, smaller trauma, rapid recovery, and fewer intra- and post-operative complications, especially pulmonary complications. The patients in this study occurred no post-operative pulmonary infection.

CONCLUSIONS

Summaries of surgical experience in this study: (1) The incision was performed at the upper edge of the 5th rib using one electric knife to enter the chest, at which place the chest wall was thinner, so that the bleeding would be less, and the intercostal blood vessels and nerves would not be easily damaged. Furthermore, this surgical point also provided ideal conditions towards the entire chest exposure and the surgical operations. The implantation of incision protective sleeve could reduce the stimuli towards intercostal nerves so as to reduce post-operative pain and discomfort. (2) Due to the narrow operating space, as well as the visual differences with conventional MPVATS, chief surgeons should first have skilled MPVATS skills, and should have good endoscopic spatial thinking and delicate operation skills. (3) Proper patient selection before surgery was also the key to success. The selected patient's lung functions should well tolerate one-lung ventilation, the tumour length should be <3 cm, pre-operative neck, chest and upper abdominal CT examinations should reveal no apparent tumour invasion, and no significant enlarged lymph node should appear beside the neck, mediastinum and left gastric artery so as to ensure the patient's intra-operative safety.

In summary, after summarised the applications of SPVATS in 10 cases of McKeown approach-based ESCC treatment, we concluded that: through proper pre-operative patient selection, conventional MPVATS could be feasibly applied to perform SPVATS plus McKeown approach-based ESCC treatment, which could also achieve the results of safely resecting oesophagus and performing standard lymph node dissection in local oesophageal region and mediastinum, as well as avoid damaging the surrounding organs and tissues. The left and right recurrent laryngeal nerves could also be protected well. Furthermore, the would could be less, and the complications could be significantly reduced, especially pulmonary complications. Patients’ post-operative chest incision pain could be significantly reduced and quicker recovered. SPVATS could be used as a new surgical option for McKeown approach-based TESCC treatment, but the standing positions of the chief surgeon and the thoracoscope holder might have certain restrictions, which also existed in conventional MPVATS when used for SPVATS plus McKeown approach-based ESCC treatment. With the experience accumulation and the improvements of endoscopic instruments, the application scale of SPVATS towards McKeown approach-based ESCC treatment would be continuously expanded so as to allow more benefits towards patients.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.