Conventionally, three gastrointestinal reconstructions after gastric resection—B-I, B-II, R-Y anastomosis—are performed in laparoscopic distal gastrectomy as well as in ODG [9, 15]. B-I anastomosis is the ideal reconstruction after gastrectomy in terms of maintaining physiological intestinal continuity and technical simplicity using a circular stapler. Therefore, many surgeons prefer this anastomosis compared to B-II or R-Y anastomosis during ODG and LADG. However, its application may be limited depending on tumor location and the size of the remnant stomach, because a remnant stomach of sufficient length is required to avoid tension in the anastomosis. In addition, delta-shaped anastomosis for intracorporeal gastroduodenostomy requires more precise laparoscopic manipulations than other types of reconstruction [16]. R-Y anastomosis can prevent reflux gastritis and esophagitis and reduces the likelihood of gastric cancer recurrence [17]. However, it is more complex and time-consuming than other types of anastomosis. Moreover, the extensive use of laparoscopic linear staplers can result in higher cost [18]. By comparison, one or two linear staplers are sufficient for intracoporeal gastrojejunostomy. B-II anastomosis is more easily applied in TLDG than B-I or R-Y anastomosis, irrespective of tumor location or of remnant stomach size [5, 19].
This study evaluated the feasibility, invasiveness, and benefit of B-II TLDG by comparing the short-term surgical outcomes in TLDG and LADG groups. In addition, this retrospective study involved a patient cohort matched 1:1 for age, sex, tumor characteristics, and TNM stage to minimize the effects of predisposing factors. Therefore, there were no differences in the baseline characteristics of patients in the two groups. We believe that this statistical method improved the accuracy of the comparison of short-term outcomes according to operative method.
As the number of reports that LADG is less invasive and provides faster recovery than ODG increases, the expectation that TLDG will also have these advantages over LADG has also increased. Indeed, several studies have compared TLDG and LADG. Song et al. [20] published a prospective, multicenter study, which showed that TLDG was more expensive but provided earlier bowel recovery than LADG and ODG. Ikeda et al. [21] reported that TLDG had several advantages over LADG including a smaller incision, less invasiveness, and better feasibility of a secure ablation. Kinoshita et al. [22] suggested that TLDG results in faster recovery, better cosmetic results, and improved quality of life in the short-term compared with LADG. Consistent with previous studies, our results showed that TLDG has advantages over LADG in terms of incision size and hospital stay. These findings suggest that B-II TLDG has better short-term outcomes than B-II LADG. In addition, there were no differences in the rates of postoperative and anastomosis-related complications between the TLDG and LADG groups. Large Korean and Japanese cohort studies have reported postoperative complication rates of 12.7% and 13.1%, respectively, for LADG [23, 24]. In this study, the postoperative complication rates were identical in the TLDG and LADG groups (5.8%). One case (1.7%) of anastomosis-related complications was found in the LADG group. Thus, we suggest that TLDG can be a safe and reliable procedure for gastric cancer.
We hypothesized that TLDG would be less invasive and be associated with improved postoperative inflammation and recovery of internal organs including the gastrointestinal tract, because, as well as a minilaparotomy at the epigastrium, pulling out of the stomach for extracorporeal anastomosis was not needed in TLDG, unlike LADG. Postoperative changes in WBC count, neutrophil count and CRP were determined to evaluate the inflammatory response. While several previous studies have reported lower WBC counts and CRP levels in TLDG compared with LADG [20, 21], our results showed no differences between groups. Therefore, additional studies using more sensitive inflammation markers, such as interlukin-6 (IL-6) and tumor necrosis factor (TNF) alpha are required to determine the superiority of TLDG in this respect.
In LADG, extracorporeal anastomosis is conducted in a limited working space with limited visual field, thus making it a difficult procedure, especially on obese patients. Extension of the laparotomy is necessary to obtain a better view for secure anastomosis on obese patients. In BMI > 25 kg/m2 patients, the operation time was shorter in the TLDG group than in the LADG group although it was not statistically significant. This finding indicates possibility that extracorporeal anastomosis needs more time because of the limited working space with restricted vision on obese patients. In this study, both TLDG and LADG were performed safely with few complications regardless of BMI. However, for obese patients, TLDG can provide more adequate working space with good visual field for the anastomosis.
Our study has several limitations. First, it was a retrospective study. Comparison between two groups was performed with limited data. More information could be collected if more variable biomarkers were used to examine, in particular, the relative invasiveness of the procedures. Second, the study size was small. However, this study was designed with a matched cohort. The enrolled patients were matched for age, sex, BMI, comorbidities, and tumor characteristics, which we would expect to compensate somewhat for its small size. Third, the surgeon’s learning curve may influence the data of this study, as enrollee selection depended upon the time period when the surgery was performed. However, as mentioned above, the surgeons already had significant experience in laparoscopic gastrectomy prior to the cases enrolled in this study. Also, as TLDG involves the same procedures as LADG for radical gastrectomy, with lymph node dissection preceding anastomosis, we believe that the effect of different operative periods should not be significant.