[Effects of robotic and laparoscopic-assisted surgery on lymph node dissection and short-term outcomes in patients with Siewert II adenocarcinoma of esophagogastric junction].

OBJECTIVE

To compare the effects of robotic and laparoscopic-assisted radical total gastrectomy on lymph node dissection and short-term outcomes in patients with Siewert type II adenocarcinoma of esophagogastric junction (AEG).

METHODS

Inclusion criteria: the tumor center was located between 2 cm above and below the esophagogastric junction and was confirmed as adenocarcinoma by endoscopic biopsy.

EXCLUSION CRITERIA

tumor with local invasion of the liver,spleen, pancreas or other organs; intraoperative finding of tumor dissemination or distant metastasis; patients undergoing palliative surgical treatment or preoperative neoadjuvant chemotherapy; patients with serious heart diseases, lung diseases, liver diseases, kidney diseases and other comorbidities; patients with multiple primary cancers;patients receiving emergency surgery. According to the above criteria, 82 patients with Siewert type II AEG who underwent gastrointestinal surgery at the Affiliated Hospital of Qingdao University from October 2014 to October 2018 were enrolled in the study. They were randomly divided into robotic surgery groups (41 cases) and laparoscopic group (41 cases) according to a computer-generated randomized allocation table. Both groups underwent radical total gastrectomy plus D2 lymph node dissection through the transabdominal esophageal hiatus approach. The intraoperative conditions and postoperative short-term outcomes were compared between two groups, including surgery time, intraoperative blood loss, length of esophagectomy, postoperative complications, postoperative gastrointestinal recovery time, length of hospital stay, postoperative unplanned reoperation rate and rehospitalization rate. Mean±SD is used for the measurement data that conforms to the normal distribution, and two independent sample t-tests are used to compare the two groups; the comparison of the count data is performed by the χ² test.

RESULTS

There were 35 males (85.4%) with age of (62.3±10.0) years and body mass index of (24.4±3.2) kg/m² in the robotic surgery group. There were 37 males (90.2%) with age of (62.5±10.0) years and body mass index of (23.8±2.6) kg/m² in the laparoscopic group. No significant differences in the baseline data between two groups were found (all P>0.05). All the patients of both groups completed R0 resection successfully without conversion to laparotomy or perioperative death. Compared with the laparoscopic group, the robotic group had less intraoperative blood loss [(70.7±39.9) ml vs. (110.2±70.6) ml, t=3.118, P=0.003], longer resected esophagus [(3.0±0.7) cm vs. (1.9±0.5) cm, t=8.759, P<0.001], but longer setup time [(56.5±7.4) minutes vs. (36.0±6.6) minutes, t=4.241, P<0.001], and higher hospitalization costs [(122 317.31±57 789.33) yuan vs. (99 401.56±39 349.53) yuan, t=2.099, P=0.039], whose differences were statistically significant (all P<0.05). The total number of harvested lymph node in the robotic surgery group was 39.2±15.3,which was significantly higher than that in the laparoscopic group (33.0±12.1) (t=0.733, P=0.047). In the robotic group and the laparoscopic group, the mediastinal lymph node No.110 and No.111 were 3.6±1.2 vs. 1.5±1.0 and 3.7±2.0 vs. 1.8±1.1, respectively, with significant difference (t=10.138, P<0.001, t=8.227, P<0.001); axillary lymph node No.19 and No.20 were 2.3±1.2 vs. 1.1±0.9 and 2.0±1.0 vs. 1.0±0.1, respectively, with significant difference (t=7.082, P<0.001,t=8.672,P<0.001). There were no significant differences in the total number of abdominal lymph node and the number of lymph node in abdominal stations between two group (all P>0.05). The highest lymph node metastasis rate was approximately 20% and observed in No.1, No.2, No.3, and No.7, followed by No.8a, No.9, No.11p, and No.110 with around 5%. The lymph node metastasis rate in other stations (No.4sa, No.4sb, No.4d, No.5, No.6, No.11d, No.12a, No.19, No.20 and No.111) was less than 5%.There were no significant differences in postoperative complication rate, postoperative fever time, postoperative exhaust and defecation time, fluid diet time, and postoperative hospital stay (all P>0.05). There were 2 patients(4.9%) with unplanned reoperation and 1 patient (2.4%) with unplanned re-admission in the laparoscopic group,while 3 patients (7.3%)with unplanned reoperation and 2 patients (4.9%)with unplanned re-admission in the robotic surgery group, whose differences were also not statistically significant (χ²=0.240,P=0.675;χ²=0.346,P=1.000).

CONCLUSION

Robot-assisted radical total gastrectomy for Siewert II AEG is safe and feasible, which is characterized by more sophisticated operation, less blood loss and higher quality of lymph node dissection, especially for subphrenic and inferior mediastinal lymph nodes.