Adjuvant chemoradiotherapy versus adjuvant chemotherapy for R1 resected gastric cancer: a retrospective cohort study

Prevention and treatment of a positive proximal margin after gastrectomy for cardia cancer

A tumour-positive proximal margin (PPM) after extended gastrectomy for oesophagogastric junction (OGJ) adenocarcinoma is observed in approximately 2-20% of patients. Although a PPM is an unfavourable prognostic factor, the clinical relevance remains unclear as it may reflect poor tumour biology. This narrative review analyses the most relevant literature on PPM after gastrectomy for OGJ cancers. Awareness of the risk factors and possible measures that can be taken to reduce the risk of PPM are important. In patients with a PPM, surgical and non-surgical treatments are available but the effectiveness remains unclear.

Effect of Chemoradiotherapy on the Survival of Resectable Gastric Cancer Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Adjuvant chemotherapy (CT) and chemoradiotherapy (CRT) after surgery are necessary to reduce the risk of metastasis and recurrence for resectable gastric cancer (GC) patients. Adjuvant CT and CRT have been proven to significantly improve the prognosis for GC patients, when compared with surgery only. However, it is still unclear whether radiotherapy offers additional survival benefits to advanced gastric cancer (AGC) patients.

METHODS

PubMed, Cochrane Library, and Embase databases were systematically searched for eligible studies that compared survival benefits between CRT and CT. The endpoints of this meta-analysis were measured as HR for OS or DFS and 95% CI using fixed- or random-effect models. Additionally, side effects, completed rate, and metastatic risk, were calculated as OR. Subgroup analyses according to clinicopathological factors were presented.

RESULTS

A total of 28 eligible studies involving 20,220 patients were included in our study. Of these, 17 studies evaluated the survival benefits of additional radiotherapy on overall survival (OS) of gastric cancer patients, ten reported the impact of CRT on disease-free survival (DFS), and 26 studies showed long-term survival rate. The pooled results were significant (HR for OS 0.84, 95% CI 0.71-0.99; HR for DFS 0.76, 95% CI 0.66-0.89). The subgroup analysis showed that adjuvant CRT increased OS for patients without preoperative treatment; showed similar nausea/vomiting, but an increased risk of neutropenia; reduced the risk of locoregional recurrence; failed to improve OS for lymph node (LN)-positive GC patients; and significantly improved prognosis for R1-treated patients. Of note, DFS was improved in all the subgroups via decreasing the locoregional recurrence.

CONCLUSION

Compared with CT, adjuvant CRT can improve survival for advanced gastric cancer patients, with similar nausea/vomiting, but increased risk of neutropenia. Patients without preoperative treatment or with positive surgical margins should be strongly recommended to undergo CRT. Treatment regimens should be carefully decided by doctors based on patients' tolerance, physical status, and reaction to treatment. Moreover, CRT improves the DFS for patients regardless of subgroups, because it significantly reduced the risk of locoregional recurrence.

Adjuvant Chemotherapy Might Be Recommended to Patients With Positive Margin After Gastrectomy: A 20-Year Retrospective Analysis in a Single Center

Background

Margin positivity after gastric cancer resection is associated with poorer outcomes. However, the prognostic factors and the choice of postoperative adjuvant treatment of patients with positive margin (PM) after gastrectomy are still being debated.

Methods

A single-center, retrospective analysis was conducted for patients with PM after gastrectomy from the China National Cancer Center Gastric Cancer Database (NCCGCDB) from 1998 to 2018. Univariate and multivariate Cox regression analyses were performed to identify prognostic factors of overall survival (OS) and recurrence-free survival (RFS).

Results

A total of 449 patients were included in the study, including 192 (42.8%) in the proximal PM group (PPM), 205 (45.7%) in the distal PM group (DPM), and 52 (11.6%) in the bilateral PM group (BPM). The 3- and 5-year OS rates for the PM patients investigated were 47.5% and 39.3%, respectively, and the 3- and 5-year RFS rates were 60.0% and 53.6%, respectively. Multivariate Cox regression analysis proved total gastrectomy (hazard ratio (HR): 1.783, 95%CI: 1.133–2.805, p = 0.012), pT4 (HR: 5.264, 95%CI: 1.493–18.565, p = 0.01), pN2 (HR: 2.263, 95%CI: 1.164–4.397, p = 0.016), pN3 (HR: 2.327, 95%CI: 1.233–4.393, p = 0.009), and combined resection (HR: 1.952, 95%CI: 1.256–3.034, p = 0.003) to be independent risk factors of OS, and pT3 (HR: 9.257, 95%CI: 1.152–74.386, p = 0.036) and pT4 (HR: 11.361, 95%CI: 1.469–87.847, p = 0.020) to be independent risk factors for RFS. Adjuvant chemotherapy prolonged OS in the PPM group (p = 0.032) and prolonged RFS in the PPM group (p < 0.001) and the DPM group (p = 0.035) compared with surgery alone.

Conclusions

Advanced pathologic stage was associated with poor prognosis, and postoperative adjuvant chemotherapy might be recommended in PM patients after gastrectomy. Still, further prospective trials are warranted to verify and support our conclusions.

Impact of adjuvant therapy in patients with a microscopically positive margin after resection for gastric and esophageal cancers

Background

A microscopically positive (R1) resection margin following resection for gastric and esophageal cancers has been documented to be a poor prognostic factor. The optimal strategy and impact of different modalities of adjuvant treatment for an R1 resection margin remain unclear.

Methods

A retrospective analysis was performed for patients with gastric and esophageal adenocarcinoma treated at the Princess Margaret Cancer Centre (PMCC) from 2006-2016. Electronic medical records of all patients with an R1 resection margin were reviewed. Kaplan-Meier and Cox proportional hazards methods were used to analyze recurrence free survival (RFS) and overall survival (OS) with stage and neoadjuvant treatment as covariates in the multivariate analysis.

Results

We identified 69 gastric and esophageal adenocarcinoma patients with a R1 resection. Neoadjuvant chemoradiation was used in 13% of patients, neoadjuvant chemotherapy in 12%, surgery alone in 75%. Margins involved included proximal in 30%, distal in 14%, radial in 52% and multiple margins in 3% of patients. Pathological staging showed 3% with stage I disease, 20% stage II and 74% stage III. Adjuvant therapy was given in 52% of R1 pts (28% CRT, 20% chemotherapy alone, 3% radiation alone, 1% reoperation). Median RFS was 14.1 months [95% confidence interval (CI), 11.1-17.2]. The site of first recurrence was 72% distant, 12% mixed, 16% locoregional alone. Median OS was 34.5 months (95% CI, 23.3-57.9) for all patients. There was no significant difference in RFS (adjusted P=0.26) or OS (adjusted P=0.83) comparing modality of adjuvant therapy.

Conclusions

Most patients with positive margins after resection for gastric and esophageal cancer had advanced pathologic stage and prognosis was poor. Our study did not find improved RFS or OS with adjuvant treatment and only one patient had reresection. The main failure pattern was distant recurrence, suggesting that patients being considered for adjuvant radiotherapy (RT) should be carefully selected. Further studies are required to determine factors to select patients with good prognosis despite a positive margin, or those who may benefit from adjuvant treatment.

Zinc Finger Protein 521, Negatively Regulated by MicroRNA-204-5p, Promotes Proliferation, Motility and Invasion of Gastric Cancer Cells

OBJECTIVE

This study aims to investigate the expression, role, and detailed mechanism of microRNA-204-5p and zinc finger protein 521 in gastric cancer.

METHODS

Immunohistochemistry was adopted to detect the expressions of zinc finger protein 521 in 82 cases of gastric cancer tissues. Western blot was used to detect the expressions of zinc finger protein 521 in gastric cancer cells and adjacent cells. Moreover, the correlation between zinc finger protein 521 and the prognosis of patients were also evaluated. Cell Counting Kit 8 assay and colony formation assay were performed to figure out the impact of zinc finger protein 521 on the proliferation of gastric cancer cells. By conducting flow cytometry, the effect of zinc finger protein 521 on the apoptosis of gastric cancer cells was determined. The scratch wound healing assay and transwell invasion assay were carried out to determine the effect of zinc finger protein 521 on regulating the motility and invasion of gastric cancer cells. Ultimately, the targeting relationship and interaction between microRNA-204-5p and zinc finger protein 521 were verified by real-time polymerase chain reaction, Western blot, and dual luciferase reporter gene assay.

RESULTS

Compared with adjacent cells, zinc finger protein 521 was highly expressed in gastric cancer cells, which was related to TNM stage (P = .0388), tumor size (P = .0168), and local lymph node metastasis (P = .0024). Overexpressed zinc finger protein 521 can promote the proliferation, migration, and invasion of gastric cancer cells and inhibit the apoptosis. Zinc finger protein 521 is a target gene of microRNA-106-5p, and there was a negative correlation between the expression of zinc finger protein 521 and microRNA-204-5p.

CONCLUSION

Zinc finger protein 521 can arrest the apoptosis and enhance the proliferation, migration, and invasion of gastric cancer cells via regulating microRNA-204-5p. Our study may provide novel clues for the treatment of patients with gastric cancer.