Two-Year Outcomes and Biomarker Analysis of Locally Advanced Gastric and Gastroesophageal Junction Adenocarcinoma After Neoadjuvant Chemotherapy and Immunotherapy from the Phase II WuhanUHGI001 Trial

BACKGROUND

This study reports the 2-year outcomes and biomarker analysis results of patients with locally advanced gastric and gastroesophageal junction (G/GEJ) adenocarcinoma who received neoadjuvant chemotherapy and immunotherapy in a phase II WuhanUHGI001 trial.

METHODS

Eligible patients with cT3/4aN+M0 locally advanced G/GEJ adenocarcinoma were screened, enrolled, and treated with 3 cycles of neoadjuvant tislelizumab and SOX followed by D2 gastrectomy and another 5 cycles of postoperative adjuvant SOX. The primary endpoint was major pathological response.

RESULTS

Of the 49 included patients, 24 (49.0%) achieved major pathological response and 13 (26.5%) achieved pathological complete response. During a median follow-up of 26.8 months, the 2-year progression-free survival (PFS) and overall survival (OS) rates were 69.4% and 81.2%, respectively. Grade 3-4 adverse events occurred in six patients (12.2%) during the neoadjuvant period, eight patients (17.0%) during the postoperative period, and seven patients (15.2%) during the adjuvant period. Biomarker analysis revealed that the pathological complete response showed no association with 2-year PFS and OS. Major pathological response showed a potentially strong association with improved 2-year PFS and OS rates. In addition, preoperative circulating tumor cells combined with pathological responses are helpful in prognosis assessment. In addition, our results showed that T downstaging, lymphocyte-to-monocyte ratio, and CD3+ T cells were independent factors that affect PFS. The signet ring cell component (SRCC), T downstaging, and neutrophil-to-lymphocyte ratio were independent factors affecting OS. Prognostic nomograms of PFS and OS constructed based on the multivariate Cox regression results demonstrated suitable calibration and discrimination ability.

CONCLUSIONS

Neoadjuvant tislelizumab plus SOX exhibits promising efficacy and acceptable toxicity in patients with locally advanced G/GEJ adenocarcinoma. In addition, our study established a prognostic risk signature and nomograms based on clinicopathological characteristics, which can accurately predict patient outcomes and aid in personalized treatment planning.

Current status of neoadjuvant immunotherapy for the treatment of gastric cancer

Gastric cancer is one of the most prevalent malignant tumors worldwide, characterized by high incidence and mortality rates. At present, comprehensive surgical treatment has enhanced the prognosis of locally advanced gastric cancer patients significantly. However, the postoperative recurrence rate remains high, and the long-term survival for patients is sub-optimal. In recent years, immunotherapy has garnered extensive attention as an innovative approach to the treatment of gastric cancer. Indeed, multiple studies have validated its therapeutic effects in advanced gastric cancer patients, leading to its incorporation into treatment guidelines. Currently, researchers are exploring the application of immunotherapy in the neoadjuvant setting globally in order to further adjust and refine neoadjuvant immunotherapy regimens for gastric cancer. This article summarizes the research progress and controversies associated with neoadjuvant immunotherapy in gastric cancer, aiming to optimize clinical benefits for gastric cancer patients undergoing this treatment approach. The retrieval methods of this study encompassed databases such as PubMed, Google Scholar, Web of Science, clinicaltrials.gov, etc. The retrieved articles included guidelines, consensus, meta-analyses, clinical trials, and reviews related to locally advanced gastric cancer published up to January 2024.

Perioperative chemotherapy with docetaxel plus oxaliplatin and S-1 (DOS) versus oxaliplatin plus S-1 (SOX) for the treatment of locally advanced gastric or gastro-esophageal junction adenocarcinoma (MATCH): an open-label, randomized, phase 2 clinical trial

BACKGROUND

It remains unclear whether addition of docetaxel to the combination of a platinum and fluoropyrimidine could provide more clinical benefits than doublet chemotherapies in the perioperative treatment for locally advanced gastric/gastro-esophageal junction (LAG/GEJ) cancer in Asia. In this randomized, phase 2 study, we assessed the efficacy and safety of perioperative docetaxel plus oxaliplatin and S-1 (DOS) versus oxaliplatin plus S-1 (SOX) in LAG/GEJ adenocarcinoma patients.

METHODS

Patients with cT3-4 Nany M0 G/GEJ adenocarcinoma were randomized (1:1) to receive 4 cycles of preoperative DOS or SOX followed by D2 gastrectomy and another 4 cycles of postoperative chemotherapy. The primary endpoint was major pathological response (MPR).

RESULTS

From Aug, 2015 to Dec, 2019,154 patients were enrolled and 147 patients included in final analysis, with a median age of 60 (26-73) years. DOS resulted in significantly higher MPR (25.4 vs. 11.8%, P = 0.04). R0 resection rate, the 3-year PFS and 3-year OS rates were 78.9 vs. 61.8% (P = 0.02), 52.3 vs. 35% (HR 0.667, 95% CI: 0.432-1.029, Log rank P = 0.07) and 57.5 vs. 49.2% (HR 0.685, 95% CI: 0.429-1.095, Log rank P = 0.11) in the DOS and SOX groups, respectively. Patients who acquired MPR experienced significantly better survival. DOS had similar tolerance to SOX.

CONCLUSIONS

Perioperative DOS improved MPR significantly and tended to produce longer PFS compared to SOX in LAG/GEJ cancer in Asia, and might be considered as a preferred option for perioperative chemotherapy and worth further investigation.

Neoadjuvant immunotherapy improves outcomes for resectable gastroesophageal junction cancer: A systematic review and meta-analysis

BACKGROUND

In recent years, neoadjuvant immunotherapy (NAIT) has developed rapidly in patients with gastroesophageal junction cancer (GEJC). The suggested neoadjuvant treatment regimens for patients with GEJC may vary in light of the efficacy and safety results.

METHODS

A search of the Cochrane Library, PubMed, Embase, and Web of Science was completed to locate studies examining the safety and effectiveness of NAIT for resectable GEJC. We analyzed the effect sizes (ES) and 95% confidence intervals (CI) in addition to subgroups and heterogeneity. Meta-analyses were performed using Stata BE17 software.

RESULTS

For these meta-analyses, 753 patients were chosen from 21 studies. The effectiveness of NAIT was assessed using the pathological complete response (pCR), major pathological response (MPR), and nodal downstage to ypN0 rate. The MPR, pCR, and nodal downstage to ypN0 rate values in NAIT were noticeably higher (MPR: ES = 0.45; 95% CI: 0.36-0.54; pCR: ES = 0.26; 95% CI: 0.21-0.32; nodal downstage to ypN0 rate: ES = 0.60; 95% CI: 0.48-0.72) than those of neoadjuvant chemotherapy (nCT) or neoadjuvant chemoradiotherapy (nCRT) (MPR < 30%; pCR: ES = 3%-17%; nodal downstage to ypN0 rate: ES = 21%-29%). Safety was assessed using the treatment-related adverse events (trAEs) incidence rate, surgical delay rate, surgical complications incidence rate, and surgical resection rate. In conclusion, the incidence of trAEs, incidence of surgical complications, and surgical delay rate had ES values of 0.66, 0.48, and 0.09, respectively. These rates were comparable to those from nCT or nCRT (95% CI: 0.60-0.70; 0.15-0.51; and 0, respectively). The reported resection rates of 85%-95% with nCT or nCRT were comparable to the mean surgical resection rate of 90%.

CONCLUSION

NAIT is an effective treatment for resectable GEJC; additionally, the level of NAIT toxicity is acceptable. The long-term effects of NAIT require further study.

Evaluation of neoadjuvant immunotherapy in resectable gastric/gastroesophageal junction tumors: a meta-analysis and systematic review

Background

Neoadjuvant therapy for resectable gastric cancer/gastroesophageal junction tumors is progressing slowly. Although immunotherapy for advanced gastric cancer/gastroesophageal junction tumors has made great progress, the efficacy and safety of neoadjuvant immunotherapy for locally resectable gastric cancer/gastroesophageal junction tumors have not been clearly demonstrated. Here, we conducted a systematic review and meta-analysis to assess the efficacy and safety of neoadjuvant immunotherapy and advance the current research.

Methods

Original articles describing the safety and efficacy of neoadjuvant immunotherapy for resectable gastric cancer/gastroesophageal junction tumors published up until October 15, 2023 were retrieved from PubMed, Embase, the Cochrane Library, and other major databases. The odds ratios (OR) and 95% confidence intervals (CIs) were calculated for heterogeneity and subgroup analysis.

Results

A total of 1074 patients from 33 studies were included. The effectiveness of neoadjuvant immunotherapy was mainly evaluated using pathological complete remission (PCR), major pathological remission (MPR), and tumor regression grade (TRG). Among the included patients, 1015 underwent surgical treatment and 847 achieved R0 resection. Of the patients treated with neoadjuvant immunotherapy, 24% (95% CI: 19%-28%) achieved PCR and 49% (95% CI: 38%-61%) achieved MPR. Safety was assessed by a surgical resection rate of 0.89 (95% CI: 85%-93%), incidence of ≥ 3 treatment-related adverse events (TRAEs) of 28% (95% CI: 17%-40%), and incidence of ≥ 3 immune-related adverse events (irAEs) of 19% (95% CI: 11%-27%).

Conclusion

Neoadjuvant immunotherapy, especially neoadjuvant dual-immunotherapy combinations, is effective and safe for resectable gastric/gastroesophageal junction tumors in the short term. Nevertheless, further multicenter randomized trials are required to demonstrate which combination model is more beneficial.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=358752, identifier CRD42022358752.

Neoadjuvant camrelizumab and apatinib combined with chemotherapy versus chemotherapy alone for locally advanced gastric cancer: a multicenter randomized phase 2 trial

Prospective evidence regarding the combination of programmed cell death (PD)-1 and angiogenesis inhibitors in treating locally advanced gastric cancer (LAGC) is limited. In this multicenter, randomized, phase 2 trial (NCT04195828), patients with gastric adenocarcinoma (clinical T2-4N + M0) were randomly assigned (1:1) to receive neoadjuvant camrelizumab and apatinib combined with nab-paclitaxel plus S-1 (CA-SAP) or chemotherapy SAP alone (SAP) for 3 cycles. The primary endpoint was the major pathological response (MPR), defined as <10% residual tumor cells in resection specimens. Secondary endpoints included R0 resection rate, radiologic response, safety, overall survival, and progression-free survival. The modified intention-to-treat population was analyzed (CA-SAP [n = 51] versus SAP [n = 53]). The trial has met pre-specified endpoints. CA-SAP was associated with a significantly higher MPR rate (33.3%) than SAP (17.0%, P = 0.044). The CA-SAP group had a significantly higher objective response rate (66.0% versus 43.4%, P = 0.017) and R0 resection rate (94.1% versus 81.1%, P = 0.042) than the SAP group. Nonsurgical grade 3-4 adverse events were observed in 17 patients (33.3%) in the CA-SAP group and 14 (26.4%) in the SAP group. Survival results were not reported due to immature data. Camrelizumab and apatinib combined with chemotherapy as a neoadjuvant regimen was tolerable and associated with favorable responses for LAGC.

Combining neoadjuvant chemotherapy with PD-1/PD-L1 inhibitors for locally advanced, resectable gastric or gastroesophageal junction adenocarcinoma: A systematic review and meta-analysis

Background

Immune checkpoint inhibitors (ICIs) have shown promising prospects in locally advanced, resectable gastric or gastroesophageal junction adenocarcinoma (GC/GEJC) immunotherapy, but their efficacy in neoadjuvant settings remains unclear. This study aimed to assess the efficacy and safety of integrating programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) inhibitors into neoadjuvant chemotherapy (NACT) of GC/GEJC treatment.

Methods

PubMed, Cochrane Library, Embase, ClinicalTrials.gov, and main oncology conference databases were systematically searched up to 19 November 2022, and randomized controlled trials (RCTs) and cohort studies that evaluated the efficacy and safety of PD-1/PD-L1 inhibitors plus NACT were included. The main outcomes were pathological complete response (pCR), major pathological response (MPR), R0 resection rate, and treatment-related adverse events (TRAEs).

Results

A total of 753 patients from 20 prospective studies were included in this meta-analysis. The pooled pCR and MPR rates from studies reporting were 21.7% [95% confidence interval (CI), 18.1%-25.5%] and 44.0% (95% CI, 34.1%-53.8%), respectively. The pooled incidence rate of total TRAEs was 89.1% (95% CI, 82.7%-94.3%), and the incidence rate of grade 3 to 4 TRAEs was 34.4% (95% CI, 17.8%-66.5%). The pooled R0 resection rate was reported to be 98.9% (95% CI, 97.0%-99.9%). Subgroup analysis has not found significant differences in efficacy and safety among different PD-1/PD-L1 inhibitors. Moreover, the efficacy in patients with positive PD-L1 expression (combined positive score ≥1) was comparable with that in the entire study population [pCR, 22.5% vs. 21.2% (p > 0.05); MPR, 48.6% vs. 43.7% (p > 0.05)].

Conclusion

This systematic review and meta-analysis found that PD-1/PD-L1 inhibitors combined with NACT for locally advanced GC/GEJC were well tolerated and may confer therapeutic advantages. The integration of ICIs into NACT has shown the potential for application in any PD-L1 expression population.

Neoadjuvant therapy with immune checkpoint blockade, antiangiogenesis, and chemotherapy for locally advanced gastric cancer

Despite neoadjuvant/conversion chemotherapy, the prognosis of cT4a/bN+ gastric cancer is poor. Immune checkpoint inhibitors (ICIs) and antiangiogenic agents have shown activity in late-stage gastric cancer, but their efficacy in the neoadjuvant/conversion setting is unclear. In this single-armed, phase II, exploratory trial (NCT03878472), we evaluate the efficacy of a combination of ICI (camrelizumab), antiangiogenesis (apatinib), and chemotherapy (S-1 ± oxaliplatin) for neoadjuvant/conversion treatment of cT4a/bN+ gastric cancer. The primary endpoints are pathological responses and their potential biomarkers. Secondary endpoints include safety, objective response, progression-free survival, and overall survival. Complete and major pathological response rates are 15.8% and 26.3%. Pathological responses correlate significantly with microsatellite instability status, PD-L1 expression, and tumor mutational burden. In addition, multi-omics examination reveals several putative biomarkers for pathological responses, including RREB1 and SSPO mutation, immune-related signatures, and a peripheral T cell expansion score. Multi-omics also demonstrates dynamic changes in dominant tumor subclones, immune microenvironments, and T cell receptor repertoires during neoadjuvant immunotherapy. The toxicity and post-surgery complications are limited. These data support further validation of ICI- and antiangiogenesis-based neoadjuvant/conversion therapy in large randomized trials and provide candidate biomarkers.

The Neo-PLANET phase II trial of neoadjuvant camrelizumab plus concurrent chemoradiotherapy in locally advanced adenocarcinoma of stomach or gastroesophageal junction

The synergistic effect of neoadjuvant immunotherapy and chemoradiotherapy in gastric adenocarcinoma is unclear. This phase II trial (NCT03631615) investigated this neoadjuvant combination in locally advanced adenocarcinoma of stomach or gastroesophageal junction. Thirty-six patients received capecitabine 850 mg/m2 twice daily and simultaneous radiotherapy for 5 weeks, sandwiched by a 21-day cycle of oxaliplatin 130 mg/m2 (day 1) plus capecitabine 1000 mg/m2 twice daily (days 1-14), respectively, followed by surgery. Camrelizumab 200 mg (day 1) was given for 5 cycles since initiating chemotherapy. Primary endpoint was pathological complete response (pCR, ypT0) rate. Secondary endpoints included total pCR (tpCR, ypT0N0) rate, major pathological response (MPR, < 10% residual tumor cells) rate, margin-free (R0) resection rate, downstaging, progression-free survival (PFS), overall survival (OS), and safety. The pCR rate was 33.3% (95% CI, 18.6-51.0), meeting pre-specified endpoint. TpCR, MPR, and R0 resection rates were 33.3%, 44.4%, and 91.7%, respectively. Twenty-eight (77.8%) patients reached ypN0. Two-year PFS and OS rates were 66.9% and 76.1%, respectively. The most common grade 3-4 adverse event was decreased lymphocyte count (27 [75.0%]). Neoadjuvant camrelizumab plus concurrent chemoradiotherapy exhibits promising pathological response in patients with locally advanced gastric adenocarcinoma, with an acceptable safety profile.