Updated analysis of SWOG-directed intergroup study 0116: a phase III trial of adjuvant radiochemotherapy versus observation after curative gastric cancer resection

In-Depth Analysis of the Necessity and Optimization Strategies for Adjuvant Radiotherapy Following Neoadjuvant Immunotherapy in the New Era of Esophageal Cancer Treatment

As immunotherapy rises to prominence in cancer treatment, the therapeutic approach to esophageal cancer is undergoing significant transformations. This review emphasizes the necessity and optimization pathways for adjuvant postoperative radiotherapy after neoadjuvant therapy in patients with esophageal cancer in the immunotherapy era. Initially, we review the advancements in neoadjuvant treatment strategies. Subsequently, we evaluate the role of postoperative radiotherapy and the latest advancements in radiotherapy target volume definition and dose optimization following neoadjuvant therapy, as well as the implications of tumor immunotherapy on postoperative radiotherapy strategies. In conclusion, in the new era of immunotherapy, postoperative radiotherapy following neoadjuvant therapy for esophageal cancer holds significant value. Optimization strategies should follow individualized treatment principles and comprehensively consider tumor biology, patient status, and treatment resources to achieve optimal therapeutic outcomes and quality of life, thereby driving continuous innovation in esophageal cancer treatment.

A Novel Transcriptomic Signature for Prediction of Response to Adjuvant Chemotherapy in Patients With Stages II and III Gastric Cancer

BACKGROUND

Predicting patients who will benefit from postoperative adjuvant chemotherapy is crucial for precision medicine. Therefore, this study comprehensively analyzed messenger RNA (mRNA) expression profiles to identify novel biomarkers and developed a prediction signature for postoperative adjuvant chemotherapy in patients with gastric cancer (GC).

METHODS

Biomarkers were discovered by analyzing two publicly available genome-wide datasets from 343 patients with pathologic stages (pStages) II and III GC. A novel prediction signature was developed based on a quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay using 137 pStages II and III GC frozen tissue specimens.

RESULTS

Nine novel mRNAs were identified as candidate biomarkers in biomarker discovery, and a Gene Expression-based ADJuvant chemotherapy Response prediction for stages II and III GC (GEx-ADJ-Res) signature was developed using these candidate biomarkers and key clinicopathologic features by qRT-PCR assay. The GEx-ADJ-Res signature robustly predicted postoperative recurrence in clinical tissue samples (area under the curve [AUC], 0.84). The signature demonstrated sufficient potential for predicting response to postoperative adjuvant chemotherapy (AUC, 0.82) and was shown to be an independent predictor of postoperative recurrence and survival in multivariate analysis. Finally, the GEx-ADJ-Res signature was successfully validated using independent multi-institutional datasets (AUC, 0.91, 0.85, and 0.78, respectively).

CONCLUSIONS

We identified the novel mRNA biomarkers and developed a novel signature that allowed robust prediction of response to postoperative adjuvant chemotherapy in patients with GC. This signature could become a precision medicine tool in GC treatment.

Gastric Carcinoma Patients with Advanced Pathological Lymph Node Stage Benefit from Postoperative Radiotherapy: A Retrospective Analysis

BACKGROUND

The relationship between regional pathological lymph node status and the benefit of postoperative radiotherapy for gastric cancer remains controversial.

METHODS

This study included all surgically treated patients diagnosed with positive histology and more than 15 examined lymph nodes between January 2007 and December 2019, using data from the SEER database. Patients who received adjuvant chemotherapy were compared by propensity score matching (PSM), with overall survival (OS) as the primary endpoint and adjuvant radiotherapy (RT) as the only variable. Results of subgroup analyses are presented in a forest plot.

RESULTS

We firstly analyzed the number of patients receiving adjuvant RT and observed a gradual decline from 2000 to 2021. A total of 1882 patients were included from 2007 to 2019, with 1301 (69.1%) in the adjuvant RT group and 581 (30.9%) in the no-adjuvant RT group. After PSM, each group included 573 patients. Overall, adjuvant RT did not significantly improve 3-year OS (55.5% vs. 51.1%, p = 0.07). However, in subgroups of patients with pathologic lymph node metastasis (pN3-stage), aged 55-70 years, with tumor size > 89 mm and T3-stage, adjuvant RT was associated with improved outcome (p < 0.05). Further PSM and survival analysis based on different pathological lymph node stages suggested an association between adjuvant RT and outcomes. Improved survival outcomes were observed in pathologically lymph node positive (pN +) and pN3 groups, but no similar effects were seen in pN1 and pN2 groups. For pN0 patients, although no statistical significance was found, the data suggest that adjuvant RT may not provide additional benefit.

CONCLUSION

Adjuvant RT was associated with significantly better prognosis in pN3-stage patients. More researches are needed to further validate the role of adjuvant RT in gastric cancer.

Association of HER2 amplification or overexpression with overall survival in advanced upper gastrointestinal adenocarcinomas

BACKGROUND

Advanced esophageal (EAC), gastroesophageal junction (GEJAC) and gastric (GAC) adenocarcinomas with HER2 amplification or overexpression (HER2+) are routinely treated with trastuzumab. However, it remains unclear if HER2+ is associated with superior overall survival (OS).

METHODS

The cohort included recurrent or de novo metastatic GAC, GEJAC and EAC from Kaiser Permanente Northern California. We used Cox regression modelling to examine association between HER2+ and OS, adjusting for demographics, performance status, CCI, receipt of chemotherapy and p53 (mutp53), KRAS (mutKRAS), CDKN2A, PIK3CA co-mutations and MYC amplification.

RESULTS

Of 875 total eligible patients, 173 had EAC, 276 had GEJAC and 426 had GAC. HER2+ was associated with better OS among the full cohort (HR = 0.74, 95% CI [0.60-0.93]), among EAC (HR = 0.62; [95% CI, 0.40-0.96]) and GEJAC (HR = 0.59; [95% CI, 0.38-0.87]), but not among GAC (HR = 0.89; [95% CI, 0.59-1.35]) patients. GEJAC had better OS than EAC (HR = 0.68, [95% CI, 0.54-0.86]). Trastuzumab treatment was associated with better OS (HR = 0.40, 95% CI [0.21-0.77]). In addition, HER2+ was associated with better OS across the molecular subgroups except that of KRAS mutation (mutKRAS). Our data also show that GEJAC, EAC and GAC were differentially associated with mutp53, mutKRAS and MYC amplification.

CONCLUSION

HER2+ and treatment with trastuzumab in HER2+ patients were associated with superior OS in upper gastrointestinal adenocarcinomas across molecular subgroups except that of mutKRAS. These results reaffirm the importance of anti-HER2 treatment in HER2+ patients and provide insight on the prognostic and biological divergence among these anatomically linked upper gastrointestinal adenocarcinomas.

Gastric cancer

Gastric cancer remains a major health challenge worldwide, with nearly 1 million new cases annually contributing to more than 650 000 deaths. Epidemiologically, gastric cancer shows substantial geographical variation in incidence, with higher rates in Asia, South America, and eastern Europe, and a rapid increase in early-onset cases among people younger than 50 years. Key risk factors for gastric cancer include Helicobacter pylori infection, diet, obesity, smoking, and genetic predisposition. Early detection through comprehensive diagnostic procedures is crucial for optimising treatment outcomes. Standard treatment approaches for locally advanced gastric cancer include surgical resection, particularly D2 lymphadenectomy, complemented by chemotherapy and radiotherapy. There is increasing implementation of minimally invasive surgical techniques for operable disease and integration of immune checkpoint inhibitors and targeted therapies for advanced stages. Emerging therapies, such as novel targeted treatments and next-generation immunotherapies, show promise in improving survival and quality of life. Future directions in the management of gastric cancer focus on precision medicine, continued advancement in immunotherapy, novel early detection methods, and a multidisciplinary approach to care. These strategies aim to enhance the overall effectiveness of treatment and prognosis worldwide.

Neoadjuvant Chemoradiotherapy in Locally Advanced Gastric Adenocarcinoma: Long-Term Results and Statistical Algorithm to Predict Individual Risk of Relapse

BACKGROUND

The purpose of this study was to evaluate the long-term outcomes of patients with locally advanced gastric adenocarcinoma (LAGC) intended to receive induction chemotherapy, chemoradiation and surgery and to develop an algorithm to estimate the individual risk of relapse in a population-based setting.

METHODS

Patients with LAGC (cT3-4 and/or N+) were retrospectively evaluated. A pathological response was graded according to the Becker criteria. The nodal regression grade was assessed by a 4-point scale (A-D). A comprehensive analysis of 155 individual patient variables was performed, and logistic regression (LR) was utilized to develop a predictive model for relapse risk.

RESULTS

From 2010 to 2024, 48 patients were analyzed. After a median follow-up of 49 months (range, 12-212), the 5-year actuarial PFS and OS rates were 44% and 48%, respectively. Four variables were identified as the most relevant features for training the LR model. Scores for the model accuracy, sensitivity and specificity (mean +/- sd) were 0.79 +/- 0.12, 0.74 +/- 0.221 and 0.88 +/- 0.14, respectively. For a validation dataset, the figures were 0.78, 0.88 and 0.73, respectively.

CONCLUSIONS

This neoadjuvant strategy seems to correlate with a favorable long-term outcome in a subset of intestinal-type LAGA patients who achieve ypN0 features.

Potential Value of AURKA and CDK6 Amplification for the Response of Patients With Gastric Cancer to Neoadjuvant Chemotherapy

Many patients respond poorly to neoadjuvant chemotherapy (NACT), negatively affecting the surgical success rate. Identifying effective biomarkers and understanding the potential resistance mechanisms are urgently needed. Data of 18 patients with advanced stomach cancer who were treated with NACT categorized according to tumor regression grade into major histological response (MJHR) and nonhistological response (NHR) groups were retrospectively analyzed. Genomic signatures associated with the response to NACT were identified using whole-exome and RNA sequencing. Extraction of molecular signatures revealed increased deficient mismatch repair signature and tumor mutation levels in the NHR group. Compared to the MJHR group, the NHR group was also characterized by a greater number of copy number alterations (p = 0.08), which was further confirmed by RNA sequencing, and upregulation of aurora kinase A (AURKA) (p = 0.05) and cyclin-dependent kinase 6 (CDK6) (p = 0.049). Western blot analysis and immunohistochemical analyses further confirmed high CDK6 (p < 0.01/p < 0.0001) and AURKA (p < 0.01/p < 0.001) expression levels in the NHR group. Finally, palbociclib, an inhibitor of CDK4/6, effectively inhibited the proliferation (p < 0.05) and induced apoptosis of oxaliplatin-resistant gastric cancer cells (p < 0.01) in vitro. These findings support the potential value of AURKA and CDK6 amplification, as well as their effects on the tumor microenvironment, in predicting poor outcomes of NACT in patients with locally advanced gastric cancer. Thus, CDK4/6 inhibitors could be used to treat NACT-resistant patients with gastric cancer.

Long-Term Prognostic Analysis of Chemoradiation Therapy Versus Chemotherapy after D2 Resection for High-Risk Gastric Cancer: Results From a Prospective Randomized Control Study

PURPOSE

To explore the population of patients who could benefit from adjuvant radiation therapy (RT) and investigated the value of postoperative chemoradiation therapy (CRT) in patients with gastric cancer after D2 resection.

METHODS AND MATERIALS

This randomized clinical trial enrolled patients between October 1, 2011, and December 31, 2019. Patients with gastric cancer who underwent D2 gastrectomy were randomized (1:1) to receive postoperative CRT or adjuvant chemotherapy after surgery. The adjuvant chemotherapy group received 8 cycles of SOX (S-1 + oxaliplatin) chemotherapy. RT was given after 4 to 6 cycles of SOX chemotherapy. RT comprised 45 Gy in 25 fractions of 1.8 Gy over 5 weeks by intensity modulated RT concurrently with S-1 chemotherapy. The primary endpoint was 3-year disease-free survival (DFS).

RESULTS

A total of 312 patients (median [IQR] age, 58 [50-64] years) were enrolled, including 157 patients randomized to the adjuvant chemotherapy group and 155 patients randomized to the adjuvant CRT group. The 3-year DFS was 66.7% for the control arm and 70.7% for the experimental arm (hazard ratio [HR], 0.82; 95% CI, 0.54-1.25; P = .35). We defined patients with pN stage ≥ N2 and extraperigastric lymph node metastasis as the high-risk group and the remaining patients as the low-risk group. The 3-year DFS rates for the high-risk group and the low-risk group were 59.3% and 76.8%, respectively (HR, 2.11; 95% CI, 1.39-3.22; P < .01). For high-risk patients, the 3-year DFS rates in the adjuvant chemotherapy and adjuvant CRT groups were 53.0% and 71.0%, respectively (HR, 0.53; 95% CI, 0.29-0.97; P < .05). More grade 3 and 4 acute toxic effects were observed in the adjuvant chemotherapy group than in the CRT group (41 patients [26.1%] vs 28 patients [18.5%]; P = .11), but the difference was not significant.

CONCLUSIONS

Subgroup analysis of this randomized clinical trial revealed that high-risk patients can benefit from adjuvant CRT.

Minimally Invasive Gastrectomy

The surgical management of gastric cancer has changed significantly from the first open partial gastrectomy in 1881 to contemporary minimally invasive approaches. The approach has shifted from open surgeries to laparoscopic and robotic-assisted gastrectomies, with evidence of reduced pain, quicker recovery, and lower morbidity with these methods. Multiple randomized trials have confirmed that laparoscopic surgeries yield oncologically safe results. Moreover, robotic surgeries, while more expensive, provide similar outcomes with some procedural benefits. Herein, we discuss surgical techniques, preoperative planning, and postprocedure care, emphasizing the role of careful clinical assessment and tailored surgical approaches based on tumor location and patient condition.

Multimodality Treatment for Locally Advanced Gastric Adenocarcinoma

Gastric cancer is prevalent worldwide and is a leading cause of cancer-related death. Patients with GC often present at advanced stages at diagnosis. Patients with locally advanced diseases experience poor survival rates with surgery alone. Multimodality therapy, including peri-operative therapy and adjuvant therapy, has improved outcomes. However, there is no consensus on the optimal treatment approach. Molecular characteristics of GC may help guide treatment choices and studies are currently underway to evaluate other treatment modalities including immunotherapy and targeted therapy.

Phase 1 Trial of Total Neoadjuvant Therapy With Short-Course Chemoradiotherapy Followed by Chemotherapy for Patients With Potentially Resectable Gastric Cancer

PURPOSE

The purpose of this phase 1 trial was to evaluate the safety and toxicity of preoperative short-course chemoradiotherapy (CRT) as part of total neoadjuvant therapy (TNT) for patients with potentially resectable gastric or gastroesophageal adenocarcinoma.

METHODS AND MATERIALS

Patients were enrolled between March 2021 and December 2022 and received CRT (30 Gy radiation in 10 fractions with concurrent capecitabine or 5-fluorouracil), then received systemic therapy for 2 months, and then underwent surgery. The primary endpoint was CRT safety; secondary endpoints were pathologic complete response, perioperative complications, and overall survival (OS).

RESULTS

Of the 24 patients enrolled in the trial, 10 (42%) had bleeding, 3 (13%) had gastric outlet obstruction, and 2 (8%) had cirrhosis. Twelve patients (50%) had clinical nodal involvement. Twenty patients (83%) had poorly differentiated tumors, and 13 (54%) had signet ring cell histology. All patients completed CRT. CRT treatment-related toxic effects included grade 3 lymphopenia in 7 patients (29%), grade 4 lymphopenia in 1 (4%), and grade 3 anemia in 1 (4%). After CRT, 22 patients (92%) received chemotherapy, 1 patient (4%) with a microsatellite instability-high tumor received immunotherapy, and 1 patient (4%) underwent resection without systemic therapy. All patients underwent attempted resection, and gastrectomy was performed in 20 (83%). The R0 resection rate was 95%. Two patients had pathologic complete response, and an additional 5 had ≤1% viable tumor. Three patients had surgical complications [grade 1 in 1 patient (4%), grade 3b in 1 (4%), and grade 4a in 1 (4%)]; no patients died within 90 days. The median follow-up time was 28 months, and median OS was not reached. The 1- and 3-year OS rates were 96% and 85%, respectively.

CONCLUSION

Short-course CRT may be safely used as part of planned TNT for patients with potentially resectable gastric or gastroesophageal adenocarcinoma. The promising rates of treatment completion, pathologic response, and OS support further research of TNT for gastric cancer.

Neoadjuvant Chemotherapy Can Effectively Avoid Unnecessary Extended Resection for Gastric Cancer with Clinical Evidence of Duodenum or Pancreas Head Involvement

Purpose: This study aims to compare the efficacy of two treatment strategies for gastric cancer with clinical evidence of pancreatic head or duodenal involvement: gastrectomy combined with pancreaticoduodenectomy (GPD) and neoadjuvant chemotherapy followed by surgery (NCS). Methods: A retrospective analysis of patient data from January 2012 to January 2022 was conducted to evaluate the outcomes of these two treatment strategies. Results: The study included 284 patients, comprising 78 in the GPD group and 206 in the NCS group. In the NCS group, 119 patients required extended pancreaticoduodenectomy, a significantly smaller proportion compared to the GPD group (p < 0.001). The NCS group successfully avoided unnecessary extended pancreaticoduodenectomy. In contrast, 15 patients in the GPD group underwent surgery despite postoperative pathological confirmation of no pancreatic head or duodenal involvement (p < 0.001). The incidence of Clavien-Dindo grade ≥ IIIb complications was significantly greater in the GPD group than in the NCS group (10.3% vs. 3.3%, p = 0.034). Overall survival was significantly longer in the NCS group, with a median of 25 months compared to 20 months in the GPD group (p = 0.0005). Multivariate Cox regression analysis revealed that tumor diameter ≥7 cm and N3 stage were independent adverse prognostic factors. Conclusion: Neoadjuvant chemotherapy is recommended for patients with gastric cancer presenting clinical evidence of pancreatic head or duodenal involvement. This approach reduces unnecessary extended surgeries, lowers complication rates, and improves overall survival.

Sedated and unsedated gastroscopy has no influence on the outcomes of patients with gastric cancer: a retrospective study

BACKGROUND

Different anesthetic drugs and techniques may affect survival outcomes for gastric cancer (GC) after surgery. In this study, we investigated the association between sedated and unsedated gastroscopy on survival outcomes in patients with GC after surgery.

METHODS

This was a retrospective study of patients who were diagnosed with GC by gastroscopy and underwent gastrectomy from January 2013 to December 2017. They were grouped based on the examination modality: propofol-based sedated gastroscopy or unsedated gastroscopy. Propensity score matching (PSM) was used to balance the baseline variables. Survival outcomes and distant metastases were compared between these two groups.

RESULTS

Finally, 673 patients were enrolled, 160 in the sedated gastroscopy group and 513 in the unsedated gastroscopy group. After PSM, there were 160 patients in each group. There was no significant difference in overall survival outcomes in the sedated gastroscopy group compared to the unsedated gastroscopy group before PSM (HR = 0.761, 95% CI: 0.531-1.091, P = 0.139) or after PSM (HR = 0.874, 95% CI: 0.564-1.355, P = 0.547). There was no significant difference in the incidence of distant metastases between the two groups before PSM (16.9% vs. 20.7%, P = 0.294) or after PSM (16.9% vs. 23.8%, P = 0.126). To confirm that our patients behaved similarly to other studies, we performed a multivariate analysis and the results showed that sex, pathological TNM stage, Borrmann type, adjuvant treatment, and surgical resection range were all independent factors affecting survival outcomes in our patients.

CONCLUSION

Our results showed no significant difference in the effects of sedated gastroscopy vs. unsedated gastroscopy on survival outcomes or distant metastases of patients after gastrectomy for GC.

Current National Treatment Trends for Gastric Adenocarcinoma in the United States

PURPOSE

The treatment of gastric adenocarcinoma (GA) continues to evolve. While neoadjuvant chemotherapy (NAC) has demonstrated emerging benefit, the optimal treatment regimen, and sequence remain to be firmly established.

METHODS

Patients with nonmetastatic GA who underwent resection were identified within the 2020 National Cancer Database. Patients were compared between the mutually exclusive treatment groups of NAC, neoadjuvant chemoradiotherapy (NCRT), adjuvant chemotherapy, adjuvant chemoradiotherapy (CRT), and surgery only. The primary endpoint was receipt of NAC or NCRT. Patients were 1-to-1 propensity score matched for receiving any neoadjuvant therapy. Multivariable logistic regression was used to identify predictors of receipt of any neoadjuvant therapy and receipt of any adjuvant therapy.

RESULTS

Twenty-five thousand and seventy-three patients were included in the analysis. Patients were treated with NAC (25.0%), NCRT (31.4%), adjuvant chemotherapy (6.5%), adjuvant CRT (12.6%), and surgery only (24.5%). Compared to 2006-2011, patients diagnosed between 2012 and 2017 experienced the greatest increases in NAC (18.6% vs. 29.0%; p < 0.001) and NCRT (25.0% vs. 35.5%; p < 0.001). Median OS was 44.9 months. OS was longest for patients who received any neoadjuvant therapy compared to those receiving adjuvant or surgery only (51.0 vs. 42.4 vs. 38.0 months, respectively; p < 0.001). Patients who were Black, in the lowest income quartile or treated at lower volume facilities were less likely to receive NAT (all p < 0.001).

CONCLUSIONS

There has been significant acceleration in the use of neoadjuvant therapy for GA. Currently, NCRT followed by surgery are the most common treatment sequences in the United States. Additional trials are needed to further define the optimal treatment sequence.

Long-term relative survival of patients with gastric cancer from a large-scale cohort: a period-analysis

BACKGROUND

Gastric cancer poses a significant global health challenge. We aim to use period analysis to assess the changes in gastric cancer treatment at our center over the past 15 years. This study reflects the current state of gastric cancer treatment at our center and provides valuable data to support clinical advancements.

METHOD

We used period analysis to evaluate the survival status of 3915 patients with gastric cancer at Nanfang Hospital, Southern Medical University, over a 15-year period spaning from 2008 to 2022. The 5-year relative survival rates were analyzed.

RESULT

Our findings indicate that the 5-year relative survival rate at our center from 2018 to 2022 is 71.4%. From 2018 to 2022, the 5-year relative survival rates for patients aged < 40, 40-54, 55-69, and ≥ 70 reached 67.5%, 73.5%, 72.0%, and 67.1%, respectively. For stage IV patients, the 5-year relative survival rate reached 29% in 2018-2022. For stage I-III patients, the 5-year relative survival rate reached 89.7% in 2018-2022. The five-year relative survival rate for patients who underwent laparoscopic surgery at our center rose from 50.3% in 2008-2012 to 71.4% in 2018-2022. Overall, there has been a notable increase in the 5-year relative survival rates, regardless of age, gender, region, or tumor stage.

CONCLUSION

Period analysis over the past 15 years shows significant improvement in the 5-year survival rate for gastric cancer at our center. This progress is due to standardized surgical techniques, perioperative management, and immunotherapy, providing robust data for evaluating the efficacy of recent treatments.

Multicriteria optimization achieves superior normal tissue sparing in volumetric modulated arc therapy for gastric cancer

OBJECTIVE

To evaluate the benefits of volumetric modulated arc therapy (VMAT) based on multicriteria optimization (MCO) for gastric cancer patients, particularly the protection of serial organs at risk (OARs) that overlap with the target volume.

METHODS

MCO and single-criterion optimization (SCO) VMAT plans were conducted among 30 gastric cancer patients, with a prescription dose of 50.4 Gy delivered in 28 fractions. All treatment plans underwent review, and a comparison was made between the active planning time and different dose-volume parameters.

RESULTS

Both the MCO and SCO VMAT plans achieved the target dose coverage, with no significant difference in the conformity index (CI) for the planning target volume (PTV), at median CI values of 0.887 and 0.891, respectively (P = 0.417). The MCO plans showed a slight but significant increase in the homogeneity index of the PTV, with a median increase of 0.029 (P < 0.001). Additionally, the MCO plans resulted in a lower D2% to the small intestine and duodenum, with reductions of 3.43 Gy and 0.3 Gy, respectively (P < 0.05). Furthermore, the Dmax to the small intestine correlated moderately with the overlapping volume between the small intestine and the target volume (ρ = 0.42, P = 0.023). Except for the mean dose to the liver, the MCO plans performed better in terms of dose indicators for other OARs. Moreover, compared to the SCO plans, the median active planning time in the MCO plans was significantly reduced by 53.2 min (P < 0.0001).

CONCLUSIONS

MCO can effectively help the physicians to quickly select an optimal treatment plan for patients with gastric cancer. It has been shown that MCO VMAT plans can significantly reduce the dose to OARs and shorten the active planning time, with acceptable target coverage. In addition, these plans take less dosimetric time, thereby streamlining the treatment planning process.

From twilight to starlight? Debating the role of chemoradiotherapy in gastric cancer in the D2 dissection era

Patients affected by resectable locally advanced gastric cancer (GC) should receive perioperative chemotherapy as a standard of care. However, an additional benefit of adjuvant chemoradiation (CRT) has been negated by modern trials in the era of extended surgical dissection, and CRT is currently only considered on an individual basis in case of suboptimal resection. However, the dismal prognosis of GC and the modest treatment completion rates of perioperative chemotherapy have pushed to reconsider CRT, particularly as a preoperative treatment, in light of modern treatment techniques, advances in the understanding of the immune landscape and development of targeted agents. The aim of this review is to critically assess the historical role of CRT, the limitations of current evidence and to debate its potential role in an integrated neoadjuvant strategy for patients with resectable GC.

SEOM-GEMCAD-TTD clinical guideline for the diagnosis and treatment of gastric cancer (2023)

Gastric cancer (GC) is the fifth most common cancer worldwide with a varied geographic distribution and an aggressive behavior. In Spain, the incidence is lower and GC represents the tenth most frequent tumor and the seventh cause of cancer mortality. Molecular biology knowledge allowed to better profile patients for a personalized therapeutic approach. In the localized setting, the multidisciplinary team discussion is fundamental for planning the therapeutic approach. Endoscopic resection in very early stage, perioperative chemotherapy in locally advanced tumors, and chemoradiation + surgery + adjuvant immunotherapy for the GEJ are current standards. For the metastatic setting, biomarker profiling including Her2, PD-L1, MSS status is needed. Chemotherapy in combination with checkpoint inhibitors had improved the outcomes for patients with PD-L1 expression. Her2 positive patients should receive antiHer2 therapy added to chemotherapy. We describe the different evidences and recommendations based on the literature.

Layer Analysis Based on RNA-Seq Reveals Molecular Complexity of Gastric Cancer

Gastric adenocarcinoma (GA) is a significant global health issue with poor prognosis, despite advancements in treatment. Although molecular classifications, such as The Cancer Genome Atlas (TCGA), provide valuable insights, their clinical utility remains limited. We performed a multi-layered functional analysis using TCGA RNA sequencing data to better define molecular subtypes and explore therapeutic implications. We reanalyzed TCGA RNA-seq data from 142 GA patients with localized disease who received adjuvant chemotherapy. Our approach included probabilistic graphical models and recurrent sparse k-means/consensus cluster algorithms for layer-based analysis. Our findings revealed survival differences among TCGA groups, with the GS subtype showing the poorest prognosis. We identified twelve functional nodes and seven biological layers, each with distinct functions. The combined molecular layer (CML) classification identified three prognostic groups that align with TCGA subtypes. CML2 (GS-like) displayed gene expression related to lipid metabolism, correlating with worse survival. Transcriptomic heterogeneity within the CIN subtype revealed clusters tied to proteolysis and lipid metabolism. We identified a subset of CIN tumors with profiles similar to MSI, termed CIN-MSI-like. Claudin-18, a key gene in proteolysis, was overexpressed across TCGA subtypes, suggesting it is a potential therapeutic target. Our study advances GA biology, enabling refined stratification and personalized treatment. Further studies are needed to translate these findings into clinical practice.

Report from the 25th Annual Western Canadian Gastrointestinal Cancer Consensus Conference on Gastric and Gastroesophageal Cancers, Winnipeg, Manitoba, 26-27 October 2023

The 25th Annual Western Canadian Gastrointestinal Cancer Consensus Conference (WCGCCC) was held in Winnipeg, Manitoba, on 26-27 October 2023. The WCGCCC is an interactive multidisciplinary conference that was attended by healthcare professionals from across Western Canada (British Columbia, Alberta, and Manitoba) who are involved in the care of patients with gastrointestinal cancer. Surgical, medical, and radiation oncologists; pathologists; oncology nurses; pharmacists; and a family physician in oncology (FPO) participated in presentation and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses current issues in the management of gastroesophageal cancers.

Survival Outcomes in Patients with Resectable Gastric Cancer Treated with Total Neoadjuvant Therapy

BACKGROUND

Perioperative chemotherapy has become the standard of care for locally advanced gastric cancer. Total neoadjuvant therapy (TNT), including both chemotherapy and chemoradiation, is utilized in other gastrointestinal malignancies. We determined survival in a contemporary cohort of gastric cancer patients treated with TNT.

METHODS

Using a prospective institutional database, patients diagnosed with cT2-4 or cN+ gastric adenocarcinoma (January 2012 to June 2022) who underwent staging laparoscopy, received TNT, and underwent gastrectomy were identified. Overall survival (OS) and disease-specific survival (DSS) were determined using standard statistical methods.

RESULTS

The study included 203 patients. The most common TNT sequence was induction chemotherapy followed by chemoradiation (n = 186 [91.6%]). A total of 195 (96.1%) patients completed planned neoadjuvant treatments. Surgery included total gastrectomy in 108 (53.2%), extended (D1+/D2) lymphadenectomy in 193 (95.1%), and adjacent organ resection in 19 (9.4%) patients. Pathologic complete response (pCR) was achieved in 32 (15.8%) patients. The 5-year OS rate was 65.2% (95% confidence interval [CI] 57.8-73.5%), and the 5-year DSS rate was 70.8% (95% CI 63.6-78.9%) in the study cohort. Among patients with pCR, the 5-year OS rate was 89.1% (95% CI 78.1-100.0%), and the 5-year DSS rate was 96.9% (95% CI 91-100%). Posttreatment pathologic N and M stages were the strongest prognostic indicators associated with both OS and DSS.

CONCLUSIONS

Total neoadjuvant therapy for resectable gastric cancer is associated with a high rate of treatment completion and promising survival outcomes. Prospective comparisons with perioperative treatment are needed to identify patients most likely to benefit from TNT.

Targeted and combination immunotherapies using biologics for gastric cancer: the state-of-the-art

INTRODUCTION

Gastric adenocarcinoma (GAC) remains a prevalent cancer worldwide and its incidence is increasing in South America. The heterogenous nature of GAC makes advances in management challenging.

AREAS COVERED

Despite challenges, recent therapeutic targets are individualizing treatment. For localized disease with microsatellite-instability-high/deficient mismatch repair, immunotherapy is now an adopted practice. In the advanced unresectable setting, those harboring human epidermal growth factor receptor-2 (HER2) expression continue to be a separate entity.

EXPERT OPINION

Future targets are developing. Among these include claudin 18.2 (CLDN18.2), fibroblast growth factor receptor 2b (FGFR2b), and trophoblast cell surface antigen-2 (TROP-2). FDA approval of zolbetuximab's, an anti-CLDN 18.2 monoclonal antibody, is expected soon. Additionally, bemarituzumab, ananti-FGFR2b monoclonal antibody, has shown improvements in combination with chemotherapy in those with HER2 negative GAC with FGFR2 overexpression. This combination is now being investigated in a phase 3 trial. Lastly, TROP-2 has emerged as an exciting solid tumor target and study is expected in GAC. All three of these therapeutic targets have seen an abundance of drug development in recent years, and we anticipate newer targeted agents driving therapeutic decisions in GAC in the coming years.

Comparison of treatment strategies based on clinical and pathological nodal status in resectable gastric adenocarcinoma

BACKGROUND

To determine the optimal multimodal treatment strategy between perioperative chemotherapy (PEC), postoperative chemoradiation therapy (POCR), and postoperative chemotherapy (POC) in resected gastric cancer (GC) patients based on nodal status.

METHODS

In this retrospective analysis, the National Cancer Database was used to identify resected non-metastatic GC (2006-2016). Patients were stratified by clinical nodal status-negative (cLN-) and positive (cLN+). In patients with cLN- disease who underwent upfront resection and were upstaged to pathological LN+, overall survival (OS) was compared between POC and POCR. In patients with cLN- and cLN+ disease, OS was compared between PEC, POCR, and POC. Kaplan-Meier survival estimate, log-rank test, and multivariable Cox proportional hazards analysis were performed.

RESULTS

We identified 7827 patients (cLN- 4828; cLN+ 2999). On multivariable analysis in patients with cLN- disease who underwent upfront resection (n = 4314) and were upstaged to pLN+ disease (70%), POCR (n = 2300, aHR 0.78, 95% CI 0.70-0.87, p < 0.001) was associated with improved OS compared to POC (n = 907). No significant difference was noted between POCR (n = 766, aHR 1.11, 95% CI 0.88-1.40, p = 0.39) and POC (n = 341) in patients with pLN- disease. On multivariable analysis in all patients with cLN- disease, POCR (n = 3066) was significantly associated with improved OS (aHR 0.84, 95% CI 0.75-0.92, p < 0.01) compared to POC (n = 1248). No significant difference was noted between POCR (aHR 1.0, 95% CI 0.70-1.01, p = 0.958) and PEC (n = 514). These results remained consistent in patients with cLN+ disease (POCR = 1602, POC = 720, PEC = 677).

CONCLUSION

Postoperative chemoradiation is associated with improved survival in GC patients upstaged from clinically node-negative disease to pathologically node-positive disease. Negative clinical nodal disease status is not a reliable indicator of pathological nodal disease.

Gastrectomies for the treatment of gastric cancer in a reference cancer center present better pathological results and survival compared to non-specialized hospitals

BACKGROUND

Some studies have shown that gastrectomy performed by experienced surgeons in high-volume specialized hospitals with the possibility of complete treatment has better results. This study aimed to compare the results of patients who underwent surgery at a reference center with non-specialized centers.

METHODS

Patients with gastric adenocarcinoma stage as pTNM II and III who underwent curative gastrectomy and were referred for adjuvant chemotherapy between 2009 and 2018 were included. Patients were divided into two groups: patients operated on in a reference center with complete oncological treatment (Reference Group); and those operated on in an external Hospital and referred for adjuvant treatment at the reference center (External Group).

RESULTS

A total of 643 patients were evaluated, 307 in the external group and 336 in the reference group. Patients in the external group were younger (58.9 vs. 62.6 years; p < 0.001) and with fewer comorbidities according to the Charlson-Deyo index (p < 0.001). The pathological result showed more dissected lymph nodes (41.4 vs. 23.5; p < 0.001) and a higher R0 resection rate (98.5% vs. 95.1%; p = 0.013) in the reference group. Patients of the external group underwent more adjuvant radiotherapy (49.5% vs. 33.9%; p < 0.001) with no difference concerning adjuvant chemotherapy (p = 0.066). Peritoneal recurrence was more common in the external group (63.2% vs 38.7%, p < 0.001). The disease-free survival rate was higher in the reference group (p < 0.001) as well as overall survival (p = 0.01).

CONCLUSION

Patients who received full oncological treatment at a reference center had better survival outcomes compared to those operated in external services.

PERIOPERATIVE CHEMOTHERAPY, ADJUVANT CHEMOTHERAPY AND ADJUVANT CHEMORADIOTHERAPY IN THE SURGICAL TREATMENT OF GASTRIC CANCER IN A HOSPITAL OF THE BRAZILIAN UNIFIED HEALTH SYSTEM

BACKGROUND

Despite the preference for multimodal treatment for gastric cancer, abandonment of chemotherapy treatment as well as the need for upfront surgery in obstructed patients brings negative impacts on the treatment. The difficulty of accessing treatment in specialized centers in the Brazilian Unified National Health System (SUS) scenario is an aggravating factor.

AIMS

To identify advantages, prognostic factors, complications, and neoadjuvant and adjuvant therapies survival in gastric cancer treatment in SUS setting.

METHODS

The retrospective study included 81 patients with gastric adenocarcinoma who underwent treatment according to INT0116 trial (adjuvant chemoradiotherapy), CLASSIC trial (adjuvant chemotherapy), FLOT4-AIO trial (perioperative chemotherapy), and surgery with curative intention (R0 resection and D2 lymphadenectomy) in a single cancer center between 2015 and 2020. Individuals with other histological types, gastric stump, esophageal cancer, other treatment protocols, and stage Ia or IV were excluded.

RESULTS

Patients were grouped into FLOT4-AIO (26 patients), CLASSIC (25 patients), and INT0116 (30 patients). The average age was 61 years old. More than 60% of patients had pathological stage III. The treatment completion rate was 56%. The pathological complete response rate of the FLOT4-AIO group was 7.7%. Among the prognostic factors that impacted overall survival and disease-free survival were alcoholism, early postoperative complications, and anatomopathological status pN2 and pN3. The 3-year overall survival rate was 64.9%, with the CLASSIC subgroup having the best survival (79.8%).

CONCLUSIONS

The treatment strategy for gastric cancer varies according to the need for initial surgery. The CLASSIC subgroup had better overall survival and disease-free survival. The INT0116 regimen also protected against mortality, but not with statistical significance. Although FLOT4-AIO is the preferred treatment, the difficulty in carrying out neoadjuvant treatment in SUS scenario had a negative impact on the results due to the criticality of food intake and worse treatment tolerance.

Locally Advanced Gastric Cancer Management: A Cost-Effectiveness Analysis

Across the nation, patients with locally advanced gastric cancer (LAGC) are managed with modalities including upfront surgery (US) and perioperative chemotherapy (PCT). Preoperative therapies have demonstrated survival benefits over US and thus long-term outcomes are expected to vary between the options. However, as these 2 modalities continue to be regularly employed, we sought to perform a decision analysis comparing the costs and quality-of-life associated with the treatment of patients with LAGC to identify the most cost-effective option. We designed a decision tree model to investigate the survival and costs associated with the most commonly utilized management modalities for LAGC in the United States: US and PCT. The tree described costs and treatment strategies over a 6-month time horizon. Costs were derived from 2022 Medicare reimbursement rates using the third-party payer perspective for physicians and hospitals. Effectiveness was represented using quality-adjusted life-years (QALYs). One-way, two-way, and probabilistic sensitivity analyses were utilized to test the robustness of our findings. PCT was the most cost-effective treatment modality for patients with LAGC over US with a cost of $40,792.16 yielding 3.11 QALYs. US has a cost of $55,575.57 while yielding 3.15 QALYs; the incremental cost-effectiveness ratio (ICER) was $369,585.25. One-way and two-way sensitivity analyses favored PCT in all variations of variables across their standard deviations. Across 100,000 Monte Carlo simulations, 100% of trials favored PCT. In our model simulating patients with LAGC, the most cost-effective treatment strategy was PCT. While US demonstrated improved QALYs over PCT, the associated cost was too great to justify its use.

Role of Preoperative Radiation Therapy for Resectable Gastric Cancer

PURPOSE

While surgery is the primary curative treatment for resectable gastric and gastroesophageal junction (GEJ) cancer, rates of locoregional and distant recurrence remain high with surgery alone, especially in more advanced disease. Multimodal approaches with perioperative therapy including chemotherapy and/or radiation therapy (RT) have thus evolved as ways to reduce the rates of disease recurrence and improve survival outcomes. This review article provides a comprehensive literature review on the role of preoperative RT for resectable gastric and GEJ cancer.

METHODS

A literature review on the role of preoperative RT for resectable gastric and GEJ cancer was conducted.

RESULTS

Preoperative RT has the potential to facilitate tumor downstaging and improved R0 resection, allowing for better locoregional control and thereby survival. For resectable locally advanced GEJ cancer, preoperative chemoradiotherapy (CRT) is currently a standard of care option along with perioperative chemotherapy, based on evidence from randomized trials. In resectable gastric cancer, however, the role of preoperative CRT is less defined with no randomized data to date, although phase II single-arm studies have shown promising results. Current standard of care for gastric cancer remains perioperative chemotherapy, with consideration for preoperative CRT in select cases.

CONCLUSION

Results from ongoing and future randomized controlled trials are expected to help define the role of preoperative CRT compared to perioperative chemotherapy alone as well as postoperative CRT for gastric and GEJ cancer.

Esophagogastric Cancer: The Current Role of Radiation Therapy

Radiation therapy is an effective treatment modality in the management of patients with esophageal cancer regardless of tumor location (proximal, middle, or distal esophagus) or histology (squamous cell vs adenocarcinoma). The addition of neoadjuvant CRT to surgery in patients who are surgical candidates has consistently shown a benefit in terms of locoregional recurrence, pathologic downstaging, and overall survival. For patients who are not surgical candidates, CRT has a role as definitive treatment.

Comparison of different treatment strategies for T3N1-3 stage gastric cancer based on the SEER database

Treatment options for T3N1 stage gastric cancer exhibit regional variation, with optimal approach remaining unclear. We derived our data from the SEER database, using Cox proportional risk regression models for univariate and multivariate analyses of 5-years overall survival (5yOS) and 5-years cancer-specific survival (5yCSS). The results showed that younger age, female, non-white race, highly differentiated histologic grade, non-Signet ring cell adenocarcinoma, low N stage, lesser curvature of the stomach, OP followed by adjuvant C/T with or without RT, partial gastrectomy, C/T and others, Radiation therapy, and Chemotherapy were significantly associated with better 5yOS and 5yCSS. For patients with stage T3N1-3 gastric cancer, multimodal treatment regimens demonstrate superior survival outcomes compared to surgery or radiotherapy alone. Among them, OP followed by adjuvant C/T with or without RT emerges as particularly efficacious, potentially offering enhanced benefits for non-Asian populations.

Adjuvant Concurrent Chemoradiotherapy (CRT) plus Docetaxel-Cisplatin-Fluorouracil (DCF) versus CRT plus Fluorouracil-Folinic Acid (FUFA) in Stage III Gastric Cancer

INTRODUCTION

Adjuvant chemoradiotherapy (CRT) is the optimal management strategy in resectable gastric cancer. There is a debate about the efficacy of more aggressive CRT plus chemotherapy regimens in adjuvant setting. This study aimed to compare the efficacy of adjuvant CRT plus docetaxel-cisplatin-fluorouracil (DCF) versus CRT plus fluorouracil-folinic acid (FUFA) in stage III gastric cancer.

METHODS

Patients with a diagnosis of stage III gastric cancer treated with adjuvant therapy after curative resection were analyzed. Patients' disease characteristics and impacts of the regimens on median disease-free survival (DFS) and median overall survival (OS) were analyzed retrospectively.

RESULTS

One hundred sixty-one patients (102 in FUFA arm and 59 in DCF arm) with a median age of 56.0 (29-79) were evaluated. In the DCF arm, there were more renal toxicities (31.6% vs 6.4% P < 0.001), emergency department admissions (64.9% vs 23.7%, P < 0.001), and dose reductions/treatment modifications in the DCF arm (51.6% vs 37.2, P < 0.001). The median follow-up was 23 months (1-124) in the FUFA arm and 26.0 months (1-77) in the DCF arm. The median DFS was 25.0 months (%95 CI, 12.7-37.2) in the DCF arm and 17.0 months (%95 CI, 2.6-31.3) in the FUFA arm, P = 0.66. The median OS was 28.0 months (%95 CI, 17.0-38.9) in the DCF arm and 25.0 months (%95 CI, 11.9-36.0) in the FUFA arm, P = 0.70.

CONCLUSION

In conclusion, when compared with FUFA regimen, more aggressive therapy with DCF was more toxic and did not improve OS in adjuvant setting of stage III gastric cancer.

Efficacy and safety of perioperative therapy for locally resectable gastric cancer: A network meta-analysis of randomized clinical trials

BACKGROUND

Gastric cancer (GC) is the fifth most commonly diagnosed malignancy worldwide, with over 1 million new cases per year, and the third leading cause of cancer-related death.

AIM

To determine the optimal perioperative treatment regimen for patients with locally resectable GC.

METHODS

A comprehensive literature search was conducted, focusing on phase II/III randomized controlled trials (RCTs) assessing perioperative chemotherapy and chemoradiotherapy in treating locally resectable GC. The R0 resection rate, overall survival (OS), disease-free survival (DFS), and incidence of grade 3 or higher nonsurgical severe adverse events (SAEs) associated with various perioperative regimens were analyzed. A Bayesian network meta-analysis was performed to compare treatment regimens and rank their efficacy.

RESULTS

Thirty RCTs involving 8346 patients were included in this study. Neoadjuvant XELOX plus neoadjuvant radiotherapy and neoadjuvant CF were found to significantly improve the R0 resection rate compared with surgery alone, and the former had the highest probability of being the most effective option in this context. Neoadjuvant plus adjuvant FLOT was associated with the highest probability of being the best regimen for improving OS. Owing to limited data, no definitive ranking could be determined for DFS. Considering nonsurgical SAEs, FLO has emerged as the safest treatment regimen.

CONCLUSION

This study provides valuable insights for clinicians when selecting perioperative treatment regimens for patients with locally resectable GC. Further studies are required to validate these findings.

Survival Benefit of Induction Chemotherapy with Paclitaxel and Carboplatin Followed by Chemoradiation Versus Postoperative Treatment in Locally Advanced Gastric Cancer: A Retrospective Cohort Study

BACKGROUND

Gastric cancer remains a prevalent worldwide illness that lacks a definitive cure. Recently, induction chemotherapy followed by concurrent chemoradiation has shown promising results in achieving a significant pathological response in locally advanced gastric cancer and improving survival rates. However, the optimal regimen for this approach continues to be a subject of discussion.

METHODS

This retrospective cohort study was conducted on treatment-naïve patients with locally advanced gastric cancer who were referred to Imam Hossain General Hospital in Tehran, Iran, between April 2016 and March 2019. Eligible patients met the criteria of clinical T3-4 or nodal-positive stage, or both, and had non-metastatic resectable tumors. The patients were categorized into two groups: (a) the neoadjuvant group, which received induction chemotherapy (carboplatin AUC 2 and paclitaxel 50 mg/m2 weekly for 12 cycles) followed by concurrent neoadjuvant chemoradiation (radiotherapy 45-50 Gy/1.8 Gy per fraction concurrent with capecitabine 500 mg/m2 BID and oxaliplatin 40 mg/m2 weekly), and (b) the adjuvant group, which was treated with standard chemoradiation or chemotherapy regimens. The two groups were compared regarding the 3-year recurrence rate and 3-year overall survival.

RESULTS

A total of 102 patients were included in the study (63.7% male, mean age ± standard deviation 56 ± 13 years). Among these, 45 patients received neoadjuvant treatment, and 57 received adjuvant treatment. The neoadjuvant group had a higher proportion of patients with advanced disease (stage III: 91.1% vs. 57.9%, P = 0.001). In the neoadjuvant group, 20 patients (44.4%) achieved a complete pathologic response, and all underwent curative surgery. The neoadjuvant group exhibited a lower 3-year recurrence rate (13 [28.9%] vs. 33 [57.9%], P = 0.003) and a higher 3-year overall survival rate (36 [80%] vs. 32 [56.1%], P = 0.003).

CONCLUSIONS

Patients receiving induction chemotherapy with paclitaxel and carboplatin followed by chemoradiation demonstrated enhanced disease control and survival compared to standard adjuvant regimens. In addition, patients treated with the applied preoperative regimen in this study showed higher pathologic response and overall survival rates than in previous studies.

Adjuvant and neoadjuvant chemotherapy for MSI early gastric cancer: a systematic review and meta-analysis

Background

Perioperative chemotherapy (CT) is an established therapeutic approach for patients diagnosed with stage IB-III gastric cancer (GC).

Objectives

This study aimed to investigate the efficacy of this approach in individuals with GC exhibiting high microsatellite instability (MSI-H).

Design

A systematic review was conducted, including studies that provided data on (neo)adjuvant CT outcomes in patients with MSI-H GC.

Methods

Systematic searches were conducted in PubMed, Cochrane Central of Controlled Trials, and Embase databases. Data were aggregated using hazard ratios (HRs) to compare overall survival between CT and surgery.

Results

Data analysis from 23 studies, including 22,011 patients, revealed that the prevalence of MSI-H is 9.8%. Administration of adjuvant or perioperative CT did not significantly reduce the risk of death or relapse in patients with MSI-H GC (HR = 0.8, 95% CI 0.54-1.16; p = 0.24 and HR = 0.84, 95% CI 0.59-1.18; p = 0.31, respectively).

Conclusion

Chemotherapy did not benefit patients diagnosed with MSI-H nonmetastatic GC but rather will be integrated with immune checkpoint inhibitors in the near future.

Neoadjuvant versus adjuvant radiotherapy for resectable locally advanced gastric cancer: A SEER population analysis

Background

There is a lack of evidence on whether resectable locally advanced gastric cancer (LAGC) patients could benefit from neoadjuvant or adjuvant radiotherapy (RT).

Methods

Patients with surgically diagnosed LAGC from 2004 to 2015 were retrieved from the SEER database. Kaplan-Meier method and the log-rank test were used to evaluate survival analysis between neoadjuvant and adjuvant RT. Univariate Cox regression was used to evaluate the hazard ratio (HR) and 95 % confidence interval (CI).

Results

A total of 4790 LAGC patients who treated with surgery and RT were identified, including 3187 patients with intestinal subtype and 1603 patients with diffuse subtype. For patients with both intestinal and diffuse subtypes, median cancer-specific survival (mCSS) was better with adjuvant RT or neoadjuvant RT. Moreover, patients benefited more from adjuvant RT than neoadjuvant RT (intestinal subtype: mCSS 49 vs. 36 months, P < 0.001; diffuse subtype: mCSS 32 vs. 26 months, P = 0.050). Further analyses showed that patients with intestinal subtype and T1-2N+, T3N-, T3N+ subgroups, as well as patients with diffuse subtype and T1-2N+ and T3N+ subgroups benefited more from adjuvant RT than those with neoadjuvant RT. Patients in the diffuse subtype and T3N- subgroups also tended benifit from adjuvant RT and survive. There was no difference in survival between the T4N- and T4N + subgroups of the two subtypes. After propensity score matching, subgroup analysis identified an improved survival in favor of adjuvant RT in the age ≥65 years and female subgroups in diffuse subtypes and T4N+ patients.

Conclusions

For patients with resectable LAGC in the T1-2N+, T3N-, T3N+ clinical subgroups, adjuvant RT yields more benefits than neoadjuvant RT or no RT, which is worthy of prospective clinical trial.

Patterns of Recurrence After Poor Response to Neoadjuvant Chemotherapy in Gastric Cancer and the Role for Adjuvant Radiation

BACKGROUND

Improved treatment strategies are needed for patients with locally advanced gastric cancer with poor response to neoadjuvant chemotherapy. We aimed to describe patterns of failure for patients with no or partial response (NR, PR) to preoperative chemotherapy.

PATIENTS AND METHODS

We analyzed patients with locally advanced gastric cancer treated from 2008 to 2022 with preoperative chemotherapy followed by surgery with D2 resection. We excluded patients who received radiation. Cumulative incidence of locoregional failure (LRF) and distant metastases (DM) were calculated. For patients with recurrent abdominal disease, hypothetical radiation clinical treatment volumes (CTV) were contoured on postoperative scans and compared with patterns of recurrence.

RESULTS

A total of 60 patients were identified. The most used preoperative chemotherapy was FLOT (38.6%), followed by FOLFOX (30%) and ECF/ECX/EOX (23.3%). Four (6.7%), 40 (66.7%), and 9 patients (15%) had a complete pathologic response (CR), PR, and NR to neoadjuvant therapy, respectively. Among patients without a CR, 3-year overall and progression-free survival rates were 62.3% (95% CI 48-76.6%) and 51.3% (95% CI 36.9-65.7%), respectively. Three-year cumulative incidence of LRF and DM were 8.4% (95% CI 0.4-16.4%) and 41.0% (95% CI 26.3-55.4%), respectively. Absolute rates of patients having the first site of recurrence encompassed by a postoperative radiation CTV was 2.0% for patients without a CR and 0% for patients with NR.

CONCLUSIONS

Patients with locally advanced gastric cancer with less than a CR to chemotherapy have poor outcomes due to high rates of DM. Adjuvant locoregional therapy such as radiation is unlikely to affect survival.

The Trends of Gastric Cancer in China From 1990 to 2019 and Predictions to 2040: A Bayesian Age-Period-Cohort Prediction Study

OBJECTIVES

This study aims to provide the most up-to-date temporal trends in incidence, mortality, and disability-adjusted life years (DALYs) of total gastric cancer in China from 1990 to 2019, and to predict the gastric cancer trends up to 2040.

METHODS

Data for the incidence, mortality, and DALYs of stomach cancer in China from 1990 to 2019 were extracted from Global Burden of Disease Study 2019 (GBD 2019). We conducted joinpoint regression analysis to explore possible segmented changes in gastric cancer trends. We predicted gastric cancer trends up to 2040 using a Bayesian age-period-cohort model.

RESULTS

The absolute incidence, mortality, and DALYs of gastric cancer increased from 1990 to 2019 in China. However, the age-standardized rates (ASRs) of incidence, mortality, and DALYs for gastric cancer decreased between 1990 and 2019, and the reductions were more pronounced for mortality and DALYs for gastric cancer.

CONCLUSION

Our study generally reveals favorable declining trends of gastric cancer incidence and predicts that this will continue to 2040. However, the high contemporary incidence combined with China's aging population will likely slow or even reverse the declining trend in gastric cancer mortality.

Great Debate: Chemoradiation Should be Added to Chemotherapy as a Neoadjuvant Treatment Strategy for Resectable Gastric Adenocarcinoma

BACKGROUND

Most patients with resectable gastric cancer present with locally advanced disease and warrant neoadjuvant chemotherapy based on level 1 evidence. However, the incremental benefit of adding radiation to chemotherapy as a neoadjuvant treatment strategy for these patients is less clear.

METHODS

While awaiting the results of two ongoing randomized clinical trials attempting to specifically address this question (TOPGEAR and CRITICS-II), this article presents the debate between two gastric cancer surgery experts supporting each side of the argument on the use or omission of neoadjuvant radiation in this setting.

RESULTS

On the one hand, neoadjuvant radiation may be better tolerated compared with modern triplet chemotherapy and may be associated with higher rates of major pathologic response. Additionally, there is evidence to suggest that radiation may offer a survival benefit when the tumor is located at the gastroesophageal junction or there is concern for a margin-positive resection. However, in the setting of adequate surgery, no survival benefit has been demonstrated by adding radiation to modern chemotherapy, likely reflecting the fact that death from gastric cancer is a result of distant recurrence, which is not addressed by local treatment such as radiotherapy.

CONCLUSION

While awaiting the results of the TOPGEAR and CRITICS-II trials, this discussion of current evidence can facilitate the refinement of an optimal neoadjuvant therapy strategy in patients with resectable gastric cancer.

Postoperative chemoradiotherapy in patients with locally advanced gastric cancer with poor pathologic response to neoadjuvant chemotherapy

PURPOSE

To evaluate the effect of postoperative chemoradiotherapy (CRT) in patients with locally advanced gastric cancer (LAGC) who respond poorly to neoadjuvant chemotherapy (ChT).

MATERIALS AND METHODS

The database of a tertiary medical center (2009-2020) was retrospectively reviewed for patients with LAGC in whom the initial treatment strategy consisted of perioperative ChT and surgery. Those who were subsequently referred for postoperative CRT because of a poor pathologic primary-tumor response (ypT3-4, ypN2-3, R1 resection) were selected for the study. CRT consisted of 45 Gy in 25 fractions of 1.8 Gy combined with capecitabine 825 mg/m2 twice daily on radiotherapy days or continuous infusion of 5-fluorouracil 180 mg/m2/day.

RESULTS

The cohort included 26 patients of median age 61 years with LAGC (clinical stage IIA-III) after surgery with D1-D2 lymphadenectomy. R0 resection was achieved in 15 (58%). The pathological stage was III in 69% (IIA-IVA). Treatment was well tolerated. During a median follow-up time of 39 months, recurrences were documented in 14 patients (54%): 11 distant and 3 locoregional. Median progression-free survival was 23 months, and median overall survival was 65 months. Estimated 5-year survival rates were 42 and 54%, respectively.

CONCLUSIONS

This small retrospective study suggests that in patients with LAGC who show a poor pathologic response to neoadjuvant ChT, a good outcome relative to reference arms in randomized trials can still be achieved with the addition of postoperative CRT. Further studies of the benefit of a tailored adaptive treatment approach to LAGC based on the response to neoadjuvant ChT are warranted.

A meta-analysis of the association between adjuvant chemoradiotherapy and disease-free survival in gastric cancer according to the histology

BACKGROUND

There are biological distinctions between gastric cancers from Eastern and Western nations, and therapeutic strategies may differ regionally. Perioperative chemotherapy, adjuvant chemotherapy, and adjuvant chemoradiotherapy (CRT) have all been demonstrated to be effective in the treatment of gastric cancer. The goal of this study was to do a meta-analysis of published studies that were eligible to see if adjuvant chemoradiotherapy was helpful for gastric cancer based on the cancer's histology.

METHOD

From inception to May 4, 2022, manual searches were conducted to identify all eligible literature using the PubMed database for the published phase III clinical trial and a randomize-controlled trial testing the role of adjuvant chemoradiotherapy in operable gastric cancer.

RESULTS

Two trials with a total of 1004 patients were selected as a result. Adjuvant CRT was found to have no effect on disease-free survival (DFS) in gastric cancer patients treated with D2 surgery (HR: 0.70 (0.62-1.02), p: 0.07). However, patients with intestinal-type gastric cancers exhibited significantly longer DFS (HR: 0.58 (0.37-0.92), p = 0.02).

DISCUSSION

After D2 dissection, adjuvant CRT improved DFS in patients with intestinal-type gastric cancers but not in those with diffuse-type gastric cancers.

Survival Outcomes and Patterns of Care for Stage II or III Resected Gastric Cancer by Race and Ethnicity

Importance

Many multimodality treatment regimens exist for gastric adenocarcinoma, including neoadjuvant vs adjuvant chemotherapy, radiation, or both. Neoadjuvant therapy is recommended in the United States for patients with locally advanced gastric cancer; however, it is unknown whether the outcomes of neoadjuvant therapy are associated with race and ethnicity.

Objective

To evaluate the differences in outcomes by race and ethnicity of patients with noncardia gastric cancer undergoing surgical procedures with and without neoadjuvant therapy.

Design, Setting, and Participants

This retrospective cohort study examined the National Cancer Database from the American College of Surgeons for patients with clinical stage II or III gastric adenocarcinoma, excluding gastric cardia tumors, undergoing surgical resection procedures from January 2006 to December 2019. Statistical analysis was performed from December 2021 to May 2023.

Exposure

Patients were stratified by race and ethnicity, and their outcomes were analyzed for those who received and did not receive neoadjuvant therapy.

Main Outcomes and Measures

The Cox proportional hazard model was used to compare overall survival (OS) between racial and ethnic groups (Asian, Black, Hispanic, and White) overall and according to receipt of neoadjuvant therapy. Among those who received neoadjuvant therapy, proportional differences in pathological responses were calculated in each group.

Results

Among a total of 6938 patients in the cohort, 4266 (61.4%) were male; mean (SD) age was 65.9 (12.8) years; 1046 (15.8%) were Asian, 1606 (24.3%) were Black, 1175 (17.8%) were Hispanic, and 3540 (53.6%) were White. Compared with other races and ethnicities, the group of White patients had significantly more who were 65 years or older with more comorbidities. White patients underwent surgical resection procedures alone without neoadjuvant or adjuvant therapy more frequently than other races and ethnicities. Asian and Black patients had the highest proportion of being downstaged or achieving pathological complete response after neoadjuvant therapy. In multivariate models, perioperative chemotherapy was associated with improved OS (HR, 0.79 [95% CI, 0.69-0.90]), whereas number of positive lymph nodes and surgical margins were associated with the largest decreases in OS. Asian and Hispanic race and ethnicity were associated with significantly improved OS compared with Black and White races (eg, Asian patients: HR, 0.64 [95% CI, 0.58-0.72]; and Hispanic patients: HR, 0.77 [95% CI, 0.69-0.85]). Black race was associated with improved OS compared with White race when receiving neoadjuvant therapy (HR, 0.78 [95% CI, 0.67-0.90]).

Conclusions and Relevance

In this large nationwide cohort study of survival outcomes among patients with resected clinical stage II or III gastric cancer, there were significant differences in response to treatment and OS between different racial and ethnic groups.

Survival and Recurrence Patterns in Patients With Stomach Adenocarcinoma Receiving Chemotherapy or Chemoradiotherapy After D2 Gastrectomy in a Tertiary Care Cancer Institute: A Retrospective Real-World Evidence Cohort Study

Purpose

Clinical trials comparing the efficacy of adjuvant chemotherapy (CT) and chemo radiation therapy (CTRT) for stomach adenocarcinoma have reported equivocal results. Hence, the current retrospective cohort study assessed the long-term survival and recurrence outcomes of these therapies, to generate evidence in a real-world scenario.

Methods and Materials

Pathologically confirmed patients with stomach adenocarcinoma aged ≥18 years who underwent gastrectomy and D2 lymph nodal dissection at a tertiary cancer hospital from January 2010 to October 2017 were enrolled. Hospital-based follow-up was performed until December 2021. Data were gathered from electronic medical records, supplemented by telephonic interviews for patients who could not come for physical follow-up. CT-alone and CTRT cohorts were compared in terms of survival and recurrence outcomes.

Results

The analysis included 158 patients (mean age, 56.42 years; 63.9% male; CT-alone cohort, 69; CTRT cohort, 89). Patients in the CTRT cohort had significantly worse tumor characteristics at baseline (29.2% had the diffuse type of tumor, 94.4% had stage II or III, 68.5% had lympho-vascular space invasion, and 85.4% had lymph node involvement). Recurrence was observed in 13 (19.7%) of the 76 followed-up patients. Although locoregional recurrence was higher in the CT-alone cohort (7 vs 2), distant metastasis was higher in the CTRT cohort (3 vs 1). The overall 5-year survival was 67.0% (SE, 5.0%) and 5-year recurrence-free survival (RFS) was 75.0% (SE, 5.0%). On multivariate Cox regression, no variable was significantly associated with the overall survival, whereas age, positive lymph nodes without extracapsular extension, and lymph node-negative were significantly associated with RFS. The CTRT cohort had significantly (84.0%) higher RFS (hazard ratio, 0.161; 95% CI, 0.056-0.464; P < .001).

Conclusions

Patients who received adjuvant CTRT after D2 dissection showed similar overall survival but significantly higher RFS than the CT-alone cohort, despite having worse baseline tumor characteristics.

ABBV-744 induces autophagy in gastric cancer cells by regulating PI3K/AKT/mTOR/p70S6k and MAPK signaling pathways

The mortality rates of gastric cancer remain high due to limited therapeutic strategies. As a highly selective inhibitor of the BD2 domain of BET family proteins, ABBV-744 has potent chemotherapeutic activity against various human solid tumors. However, whether ABBV-744 has potential anti-tumor effects in gastric cancer remain largely unknown. In this study, we evaluated the effect of ABBV-744 on gastric cancer cells and explored the possible underlying mechanisms. We found that ABBV-744 inhibited the growth of gastric cancer cells and patient-derived tumor organoids in a dose-dependent manner. Cellular experiments revealed that ABBV-744 induced mitochondria damage, reactive oxygen species accumulation, cell cycle arrest and apoptotic cell death in gastric cancer cells. Transcriptomic analysis using RNA-sequencing data identified autophagy as a crucial pathway involved in the cell death caused by ABBV-744. Mechanically, further studies showed that ABBV-744 induced autophagy flux in gastric cancer cells by inactivating PI3K/AKT/mTOR/p70S6k and activating the MAPK signaling pathways. In vivo mouse xenograft studies demonstrated that ABBV-744 significantly suppressed the growth of gastric cancer cells via inducing autophagy. Taken together, our results suggest that ABBV-744 is a novel drug candidate for gastric cancer.

Updated Adjuvant Chemotherapy for Gastric Cancer

Surgical resection is currently the best curative approach for gastric cancer (GC); however, the prognosis of patients with advanced GC remains poor even with curative resection. For this reason, perioperative chemotherapy has been combined with surgery to reduce the risk of postoperative recurrence. Standard perioperative chemotherapy for resectable advanced GC varies from region to region. Postoperative S-1 therapy was standardized via the ACTS-GC study in East Asia, perioperative ECF (Epirubicin + Cisplatin + Fluorouracil) was standardized via the MAGIC study in Europe, and postoperative chemoradiotherapy was standardized via the US intergroup study in North America. Since then, more intensive regimens have been developed. In recent years, perioperative therapy using novel agents, such as molecular-targeted drugs and immune checkpoint inhibitors (ICIs), has also been tested and evaluated in the three major regions (East Asia, Europe, and North America) with promising results. Perioperative chemotherapy has become an integral part of many treatment strategies and requires continued research and evaluation.

Perioperative chemotherapy versus adjuvant chemotherapy treatment for resectable locally advanced gastric cancer: a retrospective cohort study

BACKGROUND

Neoadjuvant chemotherapy (NAC) is increasingly used in locally advanced gastric cancer (LAGC), but the clinical safety and efficacy are still controversial. This study aims to compare perioperative chemotherapy (PEC) with adjuvant chemotherapy (AC) for resectable LAGC.

METHODS

Patients who underwent D2 gastrectomy for resectable LAGC were retrospectively reviewed, and divided into NSA group (NAC plus surgery and AC) and SA group (surgery followed by AC). The baseline characteristics and perioperative data were compared. Survival analysis was based on Kaplan-Meier method. Multivariate analyses for prognostic factors were based on the Cox regression.

RESULTS

A total of 450 patients were eligible for this study. 218 patients received NAC plus surgery and AC, while 232 upfront surgery followed by AC. The baseline characteristics were comparable between the two groups. NSA group showed significant superiority in R0 resection rate (P = 0.014), excised tumor size (P = 0.038), and tumor downstage (all P < 0.001). NAC did not affect postoperative complications or AC-related grade 3/4 adverse events. Patients in NSA group achieved significantly longer OS (P = 0.021) and DFS (P = 0.002). The Cox regression model showed that NAC was independently associated with better OS (HR 0.245, P = 0.039) and DFS (HR 0.591, P = 0.031).

CONCLUSIONS

Compared with SA, the administration of NSA was considered safe and feasible for achieving higher R0 resection rate without increasing the postoperative complications or AC-related grade 3/4 adverse events, and NAC was independently associated with better OS and DFS for resectable LAGC.

Treatment Outcomes and Prognostic Factors in N3 Stage Gastric Cancer After Curative Resection: A Real World Data

Purpose

N3 gastric cancer is characterized by a fairly high lymph node metastasis burden and poor outcome despite optimal therapy. Given the limitations of TNM classification, a comprehensive evaluation tool is necessary to predict the prognosis of patients with N3 gastric cancer who underwent curative surgery. This study aims to explore the outcomes and clinicopathologic prognostic factors affecting the overall survival (OS) of patients with N3 gastric cancer after surgery.

Methods

Data on patients with N3 gastric cancer who underwent (sub)total gastrectomy and regional lymph node dissection between November 2005 and September 2018 (n = 169) were analyzed by Cox regression to determine the independent prognostic factors for OS.

Results

The multivariable analysis established that gender, patient performance status, metastatic lymph node ratio (MLNR), tumor grade, and adjuvant chemotherapy are significantly associated with OS. The five-year OS of the study population was 15%. Adjuvant chemoradiotherapy was applied to 72% of the patients, which resulted in an improvement in recurrence-free survival but not OS. Recurrence occurred in 103 (75%) patients, in which the most frequent recurrence site was distant metastasis.

Conclusion

Male gender, poor performance status, grade 3 tumor, MLNR > 0.37, and not receiving adjuvant chemotherapy are predictors of poor prognosis in N3 gastric cancer after curative resection. Considering the high recurrence rates of this group, prospective studies are needed to optimize treatment strategies.

Randomized phase II study comparing neoadjuvant 5-fluorouracil/oxaliplatin/docetaxel versus docetaxel/oxaliplatin/S-1 for patients with type 4 or large type 3 gastric cancer

Macroscopic type 4 and large type 3 gastric cancer, mostly overlapping with scirrhous or linitis plastica type, exhibit a highly invasive nature and show unfavorable prognosis after curative surgery, even with adjuvant chemotherapy. A randomized phase III trial (JCOG0501) failed to demonstrate a survival advantage of neoadjuvant chemotherapy with S-1 plus cisplatin for this population. The current authors initiated a randomized phase II study comparing neoadjuvant chemotherapy with 5-fluorouracil/oxaliplatin/docetaxel versus docetaxel/oxaliplatin/S-1 for type 4 and large type 3 gastric cancer. 76 patients are planned to be enrolled over two years. The primary end point is the proportion of patients with a pathological response (grade 1b or higher) and secondary end points include overall survival and adverse events. Clinical Trial Registration: jRCTs031230231 (rctportal.niph.go.jp).

Tumor Differentiation as a Prognostic Marker in Clinically Staged T1bN0 Esophageal Adenocarcinoma

Current guidelines recommend that clinically staged T1N0 esophageal cancers are to be referred to surgery or endoscopic resection. Using the National Cancer Database, we identified 733 individuals with clinically staged T1N0 esophageal carcinoma, who underwent upfront surgery and did not receive any prior treatment. We assessed upstaging, which was defined as ≥ T2 disease or positive lymph nodes. Poorly differentiated adenocarcinomas were associated with upstaging, whereas squamous cell carcinomas were not. Specifically, the percentage of upstaging among individuals with clinically staged T1b and poorly differentiated tumor was 33.8%. Therefore, clinically staged T1bN0 poorly differentiated esophageal adenocarcinomas are at high risk for upstaging following surgery.