Observational Study Comparing Efficacy and Safety between Neoadjuvant Concurrent Chemoradiotherapy and Chemotherapy for Patients with Unresectable Locally Advanced or Metastatic Gastric Cancer

Survival and complications after neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy for locally advanced gastric cancer: a systematic review and meta-analysis

Background

There is increasing evidence that neoadjuvant chemoradiotherapy is superior to neoadjuvant chemotherapy for patients with locally advanced gastric cancer. However, a number of studies have come to the opposite conclusion. Therefore, our meta-analysis is to evaluate the efficacy and safety of neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy in the treatment of locally advanced gastric cancer.

Methods

We searched Wanfang Database, China National Knowledge Network database, VIP database, China Biomedical Literature Database, PubMed, Embase and Cochrane Library. The searched terms included'Stomach Neoplasms', 'Neoadjuvant Therapy' and 'Chemoradiotherapy'. The retrieval time was from the establishment of the corresponding database to September 2022, and our meta-analysis was performed using RevMan (version 5.3) and Stata (version 17) software.

Results

A total of 17 literatures were included, which involved 7 randomized controlled trials and 10 retrospective studies, with a total of 6831 patients. The results of meta-analysis showed that compared with NACT group, the complete response rate(RR=1.95, 95%CI 1.39-2.73, p=0.0001), the partial response rate(RR=1.44, 95%CI 1.22-1.71, p=0.0001), the objective response rate(RR=1.37, 95%CI 1.27-1.54, p=0.00001), the pathologic complete response rate(RR=3.39, 95%CI 2.17-5.30, p=0.00001), the R0 resection rate(RR=1.18, 95%CI 1.09-1.29, p=0.0001) and 3-year overall survival rate(HR=0.89, 95%CI 0.82-0.96, p=0.002) of neoadjuvant chemoradiotherapy group were significantly improved. The results of subgroup analyses of gastric cancer subgroup and gastroesophageal junction cancer subgroup were consistent with the overall results. Meanwhile, the stable disease(RR=0.59, 95%CI:0.44-0.81, P=0.0010) of neoadjuvant chemoradiotherapy group was lower than that of neoadjuvant chemotherapy group, and there were no statistical significance in the progressive disease rate(RR=0.57, 95%CI:0.31-1.03, P=0.06), five-year overall survival rate(HR=1.03, 95%CI:0.99-1.07, P=0.839), postoperative complications and adverse reactions between the neoadjuvant chemoradiotherapy group and neoadjuvant chemotherapy group.

Conclusion

Compared with neoadjuvant chemotherapy, neoadjuvant chemoradiotherapy might bring more survival benefits without significantly increasing adverse reactions. neoadjuvant chemoradiotherapy may be a recommended treatment for patients with locally advanced gastric cancer.

Systematic Review Registration

https://inplasy.com/inplasy-2022-12-0068/, identifier INPLASY202212068.

Neoadjuvant Chemoradiotherapy for Locally Advanced Gastric Cancer: Where Are We at?

Simple Summary

More than 50% of gastric cancer are at least locally advanced at presentation. For such patients, a multimodal approach rather than mere surgical resection leads to better long-term prognosis. Neoadjuvant chemoradiotherapy is one of the common treatment strategies for local advanced gastric cancer. Based on the experience and evidence from esophago-gastric cancers, the incorporation of systemic and locoregional therapy has shown superior disease control and reduced local recurrence. However, the optimal chemotherapy regimen, patient selection, technical consideration and potential biomarkers are still under investigation. Furthermore, the comparison of neoadjuvant chemoradiotherapy with neoadjuvant/perioperative chemotherapy is also an important issue to be answered. In the review article, we addressed the current available evidence to provide a comprehensive understanding and the use of neoadjuvant chemoradiotherapy for locally advanced gastric cancer. Future studies and ongoing trials will be necessary to determine the best candidate and the role of newer systemic and radiation therapies in such patients. NCRT is a feasible treatment option for LAGC, with the ability to achieve favorable disease control and enable higher radical resection rates over those afforded by perioperative chemotherapy or surgery alone. Large clinical trials examining the comparative efficacy of NCRT and NCT are underway. The discrepancy between the satisfactory pCR rates associated with NCRT and the nonsignificant association between NCRT and survival warrants further exploration. Furthermore, newer therapies such as immunotherapy and adaptive radiotherapy may be implemented in con-junction with NCRT, and the development of useful biomarkers may ultimately lead to the de-velopment of personalized treatments for LAGC. These research directions may lead to the dis-covery of the optimal approach to administering NCRT to patients with LAGC. They may also aid in the determination of the optimal candidates for undergoing NCRT.

Abstract

Locally advanced gastric cancer (LAGC) has a poor prognosis with surgical resection alone, and neoadjuvant treatment has been recommended to improve surgical and oncological outcomes. Although neoadjuvant chemotherapy has been established to be effective for LAGC, the role of neoadjuvant chemoradiotherapy (NCRT) remains under investigation. Clinical experience and research evidence on esophagogastric junction adenocarcinoma (e.g., cardia gastric cancers) indicate that the likelihood of achieving sustainable local control is higher through NCRT than through resection alone. Furthermore, NCRT also has an acceptable treatment-related toxicity and adverse event profile. In particular, it increases the likelihood of achieving an R0 resection and a pathological complete response (pCR). Moreover, NCRT results in higher overall and recurrence-free survival rates than surgery alone; however, evidence on the survival benefits of NCRT versus neoadjuvant chemotherapy (NCT) remains conflicting. For noncardia gastric cancer, the efficacy of NCRT has mostly been reported in retrospective studies, and several large clinical trials are ongoing. Consequently, NCRT might play a more essential role in unresectable LAGC, for which NCT alone may not be adequate to attain disease control. The continual improvements in systemic treatments, radiotherapy techniques, and emerging biomarkers can also lead to improved personalized therapy for NCRT. To elucidate the contributions of NCRT to gastric cancer treatment in the future, the efficacy, potential toxicity, predictive biomarkers, and clinical considerations for implementing NCRT in different types of LAGC were reviewed.

Surgical Efficacy and Safety of Patients with Locally Advanced Gastric Cancer following Neoadjuvant Concurrent Chemoradiotherapy and Chemotherapy

Background

The safety and efficacy of gastrectomy for locally advanced gastric cancer (LAGC) following neoadjuvant therapy have gained increasing attention. In this article, we present our preliminary treatment results and compare the surgical safety and outcomes of neoadjuvant concurrent chemoradiotherapy (CCRT) with those of chemotherapy in patients with LAGC. Patients and Methods. Sixty-three patients with a diagnosis of LAGC (clinical staging cT3N2+, cT4aN+, or cT4b) who had received neoadjuvant therapy at any period from January 2014 to December 2020 were enrolled. Among 63 patients who received neoadjuvant therapy, 38 were treated with CCRT and 25 were treated with chemotherapy. They regularly received follow-up until July 2021. The patients' characteristics, including their clinical data, perioperative results, and pathologic outcomes, were analyzed.

Results

The CCRT and chemotherapy groups did not significantly differ with respect to age, sex, or clinical stage (all p > 0.05). Finally, radical gastrectomy was performed in 15 (39.5%) patients with neoadjuvant CCRT and 10 (40.0%) patients with neoadjuvant chemotherapy. Both groups did not significantly differ with respect to operation time, blood loss, operative morbidities, or postoperative length of stay (both p > 0.05). The patients in the CCRT group exhibited favorable pathologic responses after treatment: three patients exhibited a pathologic complete response (pCR) and four, seven, and one patients exhibited a response at pathologic stages I, II, and III, respectively. By contrast, among the patients in the chemotherapy group after treatment, one patient exhibited a pCR and one, four, and four patients exhibited a response at pathologic stages I, II, and III, respectively.

Conclusions

Radical resection in patients with LAGC is challenging. This study reports that neoadjuvant CCRT is associated with better pathologic response with no increase in serious postoperative complications. However, further prospective randomized trials involving patients with LAGC receiving neoadjuvant CCRT should be conducted to verify the findings of this retrospective study.

Clinical Effectiveness of Neoadjuvant Chemotherapy in Gastric Carcinoma and Exploration of Perioperative Imaging Assessment Parameters

BACKGROUND AND AIMS

Due to the difficulty in clinical staging, a simple and feasible perioperative assessment approach for guiding personalized neoadjuvant chemotherapy (NAC) is lacking. We investigated the clinical value of NAC in advanced gastric carcinoma (GC) and the concordance between perioperative imaging and postoperative pathological assessments.

METHODS

This study included 62 patients with advanced GC who received NAC between January 2012 and December 2018. The preoperative and postoperative T stages, postoperative pathological tumor regression grade (TRG), and changes in computed tomography (CT) values after NAC were assessed. Follow-ups were conducted to obtain the median survival time (MST), and Kaplan-Meier survival curves were plotted.

RESULTS

The T stages significantly differed between before and after NAC (p = 0.001). The MST of patients in the TRG0 group was significantly different from that of patients in the TRG1+2 and TRG3 groups (p = 0.223). The percentages of positive lymph nodes were 0%, 24.17%, and 27.64% in the TRG0, TRG1+2, and TRG3 groups, respectively. TRG was correlated with changes in CT values before and after NAC, and the extent of change was associated with patient prognosis.

CONCLUSIONS

Perioperative imaging can be used to assess the short-term effectiveness of NAC for patients with GC.