Extended intraoperative peritoneal lavage as prophylactic peritoneal recurrence for locally advanced gastric cancer: a prospective randomized trial

Efficacy and Safety of Extensive Intraperitoneal Lavage for Patients with Gastric Cancer - A Systematic Review and Meta-analysis

PURPOSE

Extensive  intraperitoneal lavage (EIPL) is a novel therapeutic intervention that aims to limit the chance of peritoneal metastasis during gastrectomy. Clinical trials on using EIPL after gastrectomy show controversial results. We aimed to summarize the evidence of efficacy and safety for using EIPL after gastrectomy to limit the possibility of peritoneal metastasis and improve survival.

METHODS

A literature search on PubMed, Scopus, Embase, and Web of Sciences was conducted till June 2023 to identify eligible RCTs that assess the efficacy and safety of EIPL after gastrectomy. The hazard ratio with 95% CI was used to determine the survival probability, the risk ratio with 95% CI was used to assess the surgical outcomes, and ROB-2 and GRADE guidelines were used to assess the risk of bias and the certainty of evidence respectively.

RESULTS

Six eligible studies with a total of 1993 patients were included in the meta-analysis. Regarding survival benefits, the survival of the EIPL group did not differ significantly from the non-EIPL group, and the pooled HR of overall survival was 0.86 (95% CI 0.58-1.26) P = 0.44, the disease-free survival was 0.81 (0.58-1.13) P = 0.21, and peritoneal recurrence-free survival was 0.97 (0.79-1.2) P = 0.25. There is no significant association between EIPL and short-term postoperative outcomes. The use of EIPL does not appear to affect postoperative mortality, infection, anastomotic leakage, bleeding, ileus, or hospital stay.

CONCLUSION

Our study yielded insufficient evidence about the survival benefits and surgical outcomes of EIPL in patients with gastric cancer after gastrectomy. Therefore, it is not recommended for treating gastric cancer patients.

Molecular Cytology by One-Step Nucleic Acid Amplification (OSNA) Assay of Peritoneal Washings during D2 Gastrectomy in Advanced Gastric Cancer Patients: Preliminary Results

The presence of peritoneal free cancer cells (FCC) in gastric cancer (GC) patients is a poor prognostic factor. D2 gastrectomy may induce exfoliated FCC spread from the primary tumour or involved lymph nodes (LN). Conventional cytology for FCC detection has several limitations, whereas prophylactic use of extensive intraoperative peritoneal lavage (IPL) does not improve survival. A prospective single-arm observational study was conducted to verify whether D2 gastrectomy causes an intraoperative increase of FCC in peritoneal fluid. Twenty-seven GC patients underwent D2 gastrectomy, followed by objective quantitative measurements of CK19 mRNA level reflecting FCC with One-Step Nucleic Acid Amplification (OSNA) assay. The IPL with 3000 mL of saline was performed twice: (1) after gastrectomy with D2 lymphadenectomy and (2) after alimentary tract reconstruction. The IPL samples were analysed by initial cytology and four (1-4) consecutive OSNA assays. Initial OSNA measurement (1) revealed positive results (≥24.6 cCP/μL) in 7 (29.6%) patients. Subsequent OSNA measurements showed a significant decrease in the FCC level after D2 gastrectomy (1 vs. 2; p = 0.0012). The first IPL induced a non-significant increase in the FCCs (2 vs. 3, p = 0.3300), but the second IPL reversed it to normal levels (3 vs. 4, p = 0.0.0574). The OSNA assay indicates a temporal intraoperative increase in the peritoneal FCC in advanced GC patients undergoing D2 gastrectomy. Two consecutive IPLs are necessary to reverse the increase of CK19 mRNA level in peritoneal washings.

Does Extended Intraoperative Peritoneal Lavage Really Bring Benefit on Patients With Gastric Cancer? A Meta-Analysis of Published Clinical Trials

Purpose

The purpose of the current meta-analysis is to analyze whether extended intraoperative peritoneal lavage (EIPL) can bring benefit on short-term outcomes or survival for patients undergoing curative gastrectomy for gastric cancer.

Methods

The PubMed, Embase, and Cochrane Library databases were searched from inception to May 3, 2021, to find eligible studies. Postoperative complications, overall survival (OS), disease-free survival (DFS), and peritoneal recurrence-free survival (PRFS) were compared between EIPL group and No EIPL group.

Results

A total of five randomized controlled trials with 1,790 patients were included in the current meta-analysis. No difference was found in baseline information (p > 0.05). After pooling up the data of overall postoperative complications, no significant difference was found between EIPL group and No EIPL group (OR = 0.88, 95% CI = 0.51 to 1.53, P = 0.65). Furthermore, there was no significant difference between EIPL group and No EIPL group in terms of OS (HR = 0.77, 95% CI = 0.36 to 1.64, P = 0.49), DFS (HR = 0.97, 95% CI = 0.71 to 1.33, P = 0.87), and PRFS (HR = 1.03, 95% CI = 0.74 to 1.43, P = 0.86). In terms of subgroup analysis of OS, no significant difference was found as well (HR = 1.05, 95% CI = 0.82 to 1.34, P = 0.69).

Conclusions

EIPL did not bring benefit in terms of short-term outcomes or survival. Therefore, EIPL is not recommended for patients undergoing curative gastrectomy for gastric cancer.