Is totally laparoscopic gastrectomy without prophylactic drains feasible for patients with distal gastric cancer? The experience of China National Cancer Center CURRENT

Prophylactic drains have been used to remove intraperitoneal collections and to detect complications early in open surgery. In the last decades, Gastric cancer minimally invasive surgery has been widely carried out throughout the world. However, little has been reported on routine prophylactic abdominal drainage after totally laparoscopic distal gastrectomy. To evaluate the feasibility of without prophylactic drains in totally laparoscopic distal gastrectomy in selective patients. Data of distal gastric cancer patients underwent totally laparoscopic distal gastrectomy with and without prophylactic drainage at China National Cancer Center/Cancer Hospital from February 2018 to August 2019 were reviewed. The outcomes of patients with and without a prophylactic drainage were compared.


Abstract Background
Prophylactic drains have been used to remove intraperitoneal collections and to detect complications early in open surgery. In the last decades, Gastric cancer minimally invasive surgery has been widely carried out throughout the world. However, little has been reported on routine prophylactic abdominal drainage after totally laparoscopic distal gastrectomy. To evaluate the feasibility of without prophylactic drains in totally laparoscopic distal gastrectomy in selective patients.

Methods
Data of distal gastric cancer patients underwent totally laparoscopic distal gastrectomy with and without prophylactic drainage at China National Cancer Center/Cancer Hospital from February 2018 to August 2019 were reviewed. The outcomes of patients with and without a prophylactic drainage were compared.

Results
A total of 420 patients who underwent surgery for gastric cancer were identified; of these, 88 patients who received totally lapaoscopic distal gastrectomy were included. The incidence of concurrent illness was higher in the drain group, (48.8% vs. 27.7%, p = 0.041). The overall postoperative complication rate was 19.5% in the drain group (n = 47), and 10.6% in the no-drain group (n = 41), there were no significant differences between two groups (p > 0.05). The need for percutaneous catheter drainage (PCD) was also not significantly different between groups (9.8% vs. 6.4%, p = 0.700). However, patients with larger BMI (≥ 29) are prone to postoperative complications (p = 0.042). In addition, more operating time cost in the drain group than in the no-drain group (188. 10  In recent ten years, gastric cancer is still one of the most frequently occurring malignancies worldwide. In 2017, there were about 1 million new cases of gastric cancer worldwide, which was the fifth most common malignancy, and the death rate was 783,000, which was the third highest malignant tumor (1).In China, it was estimated that there were 677,000 new gastric cancer cases in China in 2015, accounting for half of the new gastric cancer cases in the world (2).
In 1994, Kitano reported the first case of laparoscopic assisted distal gastrectomy(LADG) with D2 lymphadenectomy (3), the recent South Korea multi-center clinical study also confirmed the operation was safe and effective treatment method (4), with the development of surgical instruments and the progress of technology, early gastric cancer minimally invasive surgery has been widely carried out throughout the world. Meanwhile, the interim results of class 01 clinical trial led by China southern hospital showed that the efficacy of laparoscopic surgery for advanced distal gastric cancer was comparable to that of open surgery (5).
With the development of laparoscopic surgery for gastric cancer, many surgeons begin to use totally laparoscopic surgery for distal gastric cancer, compared with laparoscopic assisted surgery, totally laparoscopic distal gastrectomy (TLDG) for reconstruction of digestive tract anastomosis is intra cavitary anastomosis, which does not require auxiliary small incision. The reconstruction of TLDG's anastomosis can have a safer anastomosis regardless of tumor location, with lower incidence of incision problems than LADG, and can be performed better in obese patients (6,7).

Totally Laparoscopic Distal Gastrectomy
The extent of gastrectomy and lymph node dissection was determined based on the Japanese gastric cancer treatment guidelines (9) .The operator was on the left side of the patient to finish laparoscopic ligation and division, the first assistant was positioned on the opposite. A cameraman stood between the patients' legs. A five-port system (i.e., two 5 mm and three 12 mm ports) was used for each totally laparoscopic distal gastrectomy. 10 mm flexible laparoscopes were used with CO2 pressure maintained at 13-15 mmHg.
The operator was on the left side of the patient to performed Billroth-I reconstruction using mortified delta-shaped anastomosis(10) or overlap anastomosis (8). Performing Billroth-II or Roux-en-Y reconstruction on the right side of the patients.

Postoperative Management
Patients in both groups were given prophylactic antibiotics half an hour before surgery. The decision of whether to use a prophylactic drain was made by the surgeon. Oral intake of water was initiated on the first day after the surgery. Soft diet was initiated after patient could tolerate liquid meals and postoperative UGIs confirmed the absence of anastomotic leakage.

Outcome Assessment
The clinical, operative, and pathological variables were compared between the two groups based on the information obtained from our prospectively collected surgical database. Early postoperative complications (occurring on postoperative days 0-30) were graded using the Clavien-Dindo classification. Early postoperative complications requiring medical, radiological, or surgical interventions (grade 2 or higher) were regarded as an event. The occurrence of postoperative complication risk was also assessed.

Statistical Analysis
All values were expressed as mean ± SD. Using χ2 test and Student's t test for comparing the clinical characteristics categorical variables and continuous variables, respectively. For categorical data, the chi-squared test or Fisher's exact test is performed. A P value of < 0.05 was considered significant.
Statistical analysis was performed using the SPSS.20. Table 1 shows the clinical characteristics of patients undergoing TLDG with or without prophylactic drain. Between two groups no significant differences were observed in patient sex, age, BMI, ASA-PS, pTstage, pNstage, the number of patients with a previous abdominal operation, and the number receiving neoadjuvant chemotherapy, only in preoperative concurrent illness, the drain group was significantly higher than the no-drain group (48.8% vs. 27.7%, p < 0.05).

Short-time Outcomes
Postoperative patient complications are listed in Table 4. No mortality was recorded for both groups.
The overall postoperative complication rate was 19.5% in the drain group, and 10.6% in the no-drain group (p > 0.05).There were no anastomotic bleeding, anastomotic Leakage, lymph leakage, lleus and pancreatic fistula occur in either group. Clavien-Dindo grade 3 complication comprise duodenal stump leakage (n = 2), intra-abdominal abscess (n = 2) and intra-abdominal bleeding (n = 1) in the drainage group. The need for PCD was not significantly different between groups (9.8% vs. 6.4%, p = 0.700). prophylactic drain may thus be useful in patients at higher risk and in those with larger BMI or more concurrent illness.

Discussion
Since 2015, totally laparoscopic surgery has been widely used in clinical practice, but there are few articles on whether totally laparoscopic surgery requires prophylactic drains (10,11). Most of studies about prophylactic drains were based on open gastrectomy, Cochrane review by Wang et al., which included four single-institution, randomized controlled trials that sought to evaluate the role of PD placement in the setting of any type of gastric resection for gastric cancer (12)(13)(14). In this study, we reviewed the clinicopathological data of gastric cancer patients in our treatment group during the past two years, and found that routine prophylactic drains were not necessary in selective patients. A prophylactic drain may be useful in patients at higher risk.
It is generally believed that prophylactic drains are used to enhance early detection of complications, prevent collection of fluid, reduce morbidity and mortality, and decreases the duration of hospital stay (15,16), the present study results had shown that there was no significant difference between two groups in postoperative hospital stay, while there was a trend: the length of postoperative hospital stay in no drain group was shorter than in drain group (

Conclusion
In conclusion, without using PD in selective patients during gastric cancer surgery is possible which can significantly improve the postoperative comfort of patients and doesn't increase risk of postoperative complications.

Limitations
Here is a retrospective study, selection bias is unavoidable, for example the differences between two groups of data in concurrent illness maybe lead to more postoperative complications in drain group, and the decision regarding whether to use a PD is decided by surgeon. Another limitation is that this study only enrolled the patients undergone gastrectomy in our center during the last two years, which means results are not universal. Thus, we are going to perform a randomized, controlled trial to compare the outcomes between routinely used PD group and selectively used PD based on the present study.

Ethics approval and consent to participate
This study was approved by the Institutional Review Board at the Cancer Hospital of the Chinese Academy of Medical Sciences. Written informed consent was obtained from all patients, and the data were anonymously analyzed.

Consent for publication
Not applicable.

Availability of data and material
The datasets supporting the conclusions of this article are available from the corresponding author on demand.

Competing interests
The authors declare that they have no competing interests. The funding body did not contribute to the design of the study and collection, analysis, and interpretation of data, or in writing the manuscript.
Author contributions: Hao Liu and Peng Jin contributed equally to this work and they were involved in concept, data interpretation, wrote the first draft, and revised it critically in light of comments from other authors; Quan Xu and Fuhai Ma analyzed the data. Shuai Ma and Yibin Xie collected the patient's clinical data. Yantao Tian was involved in study conception and design, data interpretation, manuscript revision, and discussion; all authors approved the final version submitted. Figure 1 CONSORT diagrams. Flowchart of the patients assessed in this study Figure 1 CONSORT diagrams. Flowchart of the patients assessed in this study