Impact of surgical margin status on the survival outcome after surgical resection of gastric cancer: a protocol for systematic review and meta-analysis

Surgical resection for patients with recurrent or metastatic gastrointestinal stromal tumors: a protocol for a systematic review and meta-analysis update

BACKGROUND

There are limited data on the clinical benefits of adding surgical resection in patients with recurrent or metastatic gastrointestinal stromal tumors (GISTs). This protocol outlines the planned scope and methods for a systematic review and meta-analysis update that will compare the clinical outcomes of surgical resection combined with tyrosine kinase inhibitor (TKI) with TKI treatment alone in patients with recurrent or metastatic GISTs.

METHODS

This review will update a previously published systematic review by our team. This protocol is presented in accordance with the PRISMA-P guideline. PubMed, Embase, and Cochrane Central Register of Controlled Trials will be systematically searched and supplemented by a secondary screening of the references of all included studies. We will include randomized controlled trials (RCTs) and non-randomized studies (NRS) in this review update. The outcomes evaluated will be overall survival and progression-free survival. Two reviewers will independently screen and select studies, extract data from the included studies, and assess the risk of bias of the included studies. Data extracted from RCTs and NRS will be analysed and reported separately. Preplanned subgroup analyses and sensitivity analyses are detailed within this protocol. The strength of the body of evidence will be assessed using GRADE.

DISCUSSION

This systematic review and meta-analysis update will provide a current assessment of the evidence for the role of surgery in patients with recurrent or metastatic advanced GISTs. These findings will be used by the Chinese Society of Clinical Oncology (CSCO) GIST guideline recommendations on surgical treatment for recurrent or metastatic advanced GIST patients in China.

SYSTEMATIC REVIEW REGISTRATION

This protocol was prospectively registered in the Open Science Framework Registry ( https://osf.io/xus7m ).

Impact of Surgical Margin Status on Survival in Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

It is inconclusive whether R1 margin determined by postoperative pathological examination indicates worse long-term survival in gastric cancer (GC) patients after curative intent resection (CIR). Hence, we aimed to systematically pool the conflicting evidence to fill this gap.

METHODS

The present study was performed according to the published protocol and Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Published studies examining the impact of microscopic margin status on overall survival (OS) and 5-year OS rate in GC were systematically searched in PubMed, Embase, and Cochrane Library databases. RevMan 5.3 was used to conduct statistical analysis, and the Grading of Recommendations, Assessment, Development, and Evaluations approach was used to assess the certainty of evidence for each outcome.

RESULTS

Twenty-three retrospective cohort studies including 19 992 patients were analyzed. The pooled hazard ratio for OS of 14 studies was 2.06 (95% confidence interval [CI]: 1.61-2.65, low certainty), indicating that R1 margin predicted inferior OS. Subgroup and sensitivity analyses upheld the statistical stability of this finding. The pooled odds ratio (OR) of 14 studies was .21 (95% CI: .17-.26, moderate certainty), demonstrating that the presence of R1 margins was associated with a poorer 5-year OS rate. Sensitivity analyses and most of the subgroup analyses confirmed this finding, except the "esophagogastric junction (EGJ) cancers" subgroup, which included two studies with a pooled OR of .41 (95% CI: .10-1.61).

CONCLUSION

R1 margin detected by pathological examination might exhibit a high correlation with poorer OS and 5-year OS rate in GC (except EGJ cancers) patients who underwent CIR. To figure out the effect of R1 margin on survival of different stages and histological types need prospective studies with large sample sizes and standardized methods. What is the best treatment for R1 margin patients also need more in-depth and special research.

Surgical Management of Gastric Cancer: A Systematic Review

Gastric cancer is the fifth most common cancer worldwide, and it is responsible for 7.7% of all cancer deaths. Despite advances in the field of oncology, where radiotherapy, neo and adjuvant chemotherapy may improve the outcome, the only treatment with curative intent is represented by surgery as part of a multimodal therapy. Two concepts may be adopted in appropriate cases, neoadjuvant treatment before gastrectomy (G) or primary surgical resection followed by chemotherapy. Such an approach, combined with early detection and better screening, has led to a decrease in the overall incidence of gastric cancer. Unfortunately, malignant tumors of the stomach are often diagnosed in locally advanced or metastatic stages when the median overall survival remains poor. Surgical care in these cases must be provided by a multidisciplinary team in a high-volume center. Important surgical aspects such as optimum resection margins, surgical technique, and number of harvested lymph nodes are important factors for patient outcomes. The standardization of surgical treatment of gastric cancer in accordance with the patient’s profile is of decisive importance for a better outcome. This review aims to summarize the current standards in the surgical treatment of gastric cancer.