Stage-specific effect of adjuvant therapy following gastric cancer resection: a population-based analysis of 4,041 patients

A new scoring system to evaluate adjuvant chemotherapy for patients with T2N0M0 gastric cancer after D2 gastrectomy

BACKGROUND

At present, there is insufficient medical evidence to determine whether adjuvant chemotherapy is necessary for T2N0M0 gastric cancer.

AIM

To obtain a risk score to assess the need for adjuvant chemotherapy in patients with T2N0M0 gastric cancer.

METHODS

We identified 325 patients with pathological T2N0M0 stage primary gastric cancer at the National Cancer Center between 2011 and 2018. Univariate and multivariate Cox regression analyses were performed to predict factors affecting prognosis. Vascular invasion, tumor site, and body mass index were assessed, and a scoring system was established. We compared the survival outcomes and benefits of adjuvant chemotherapy between the different subgroups.

RESULTS

Five-year survival rates of the score 0, 1, 2, and 3 groups were 92%, 95%, 80%, and 50%, respectively (P < 0.001). In the score 2-3 group, five-year survival rates for patients in the adjuvant chemotherapy group and postoperative observation group were 95% and 61%, respectively (P = 0.021).

CONCLUSION

For patients with T2N0M0 stage gastric cancer and two or more risk factors, adjuvant chemotherapy after D2 gastrectomy may have a survival benefit.

GSTM3 deficiency impedes DNA mismatch repair to promote gastric tumorigenesis via CAND1/NRF2-KEAP1 signaling

Gastric cancer (GC) is one of the most severe gastric diseases worldwide. However, the molecular basis that drives tumorigenesis and progression is not completely understood, which hinders the efficacy and development of therapeutic options. Glutathione-S-transferases (GSTs) are a group of phase II detoxification enzymes that maintain redox homeostasis; however, their roles in cancers are not well defined. Here, we revealed that the expression of GST family members is significantly impaired in GC tissues. Glutathione-S-transferase mu 3 (GSTM3), a member of GST family, is dramatically downregulated in cancerous tissues and has been identified as an independent prognostic factor in GC associated with tumor differentiation, inhibiting GC cell proliferation and migration in vitro and in vivo. Mechanistically, GSTM3 is transcriptionally activated by NRF2/KEAP1 signaling. As a feedback loop, GSTM3 binds to Cullin-associated and neddylation-dissociated 1 protein (CAND1), an exchange factor for integrating Kelch-like ECH-associated protein 1 (KEAP1) into Cul3-RING ubiquitin ligases (CRL3), to disrupt nuclear factor-erythroid factor 2-related factor 2 (NRF2)/KEAP1 binding and prevent NRF2 ubiquitination and degradation, leading to its activation. A deficiency in glutathione S-Transferase Mu 3 (GSTM3) reduces DNA mismatch repair (MMR) gene expression and increases mutagenesis via CAND1/NRF2 binding. Importantly, GSTM3/NRF2 and KEAP1 were negatively and positively associated with the genomic signature for microsatellite instability, respectively. Clinically, GSTM3, NRF2, and MutS homolog 6 (MSH6) were positively correlated in the GC specimens. This study uncovered a reciprocal regulation between GSTM3 and NRF2 and established a functional and clinical link between GSTM3-NRF2/KEAP1 and MMR during GC cell proliferation and progression, thus providing potential therapeutic targets for GC.

Adjuvant Chemotherapy in pT2N0M0 Gastric Cancer: Findings From a Retrospective Study

Background: There is no global consensus on adjuvant chemotherapy (ACT) for pT2N0M0 gastric cancer. We conducted a retrospective study to reveal the role of ACT in such patients.

Methods: Patients with pT2N0M0 gastric cancer who underwent radical resection with D2 lymphadenectomy for primary gastric cancer between January 2012 and May 2016 were included. Kaplan–Meier and Cox regression were used to evaluate overall survival (OS), disease-specific survival (DSS) and predictors of prognosis. Stratified analysis based on high-risk factors was conducted.

Results: Of enrolled 307 patients, 111 patients underwent surgery alone and 196 patients received ACT. Surgery alone (HR = 2.913, 95% CI: 1.494-5.682, p = 0.002) and total gastrectomy (HR = 2.445, 95% CI: 1.279-4.675, p = 0.007) were independently associated with decreased OS. With the median follow-up of 73.1 months, the 5-year OS rate was 87.9% and 5-year DSS rate was 91.8%. Patients receiving ACT showed a better 5-year OS rate (92.9 vs. 79.3%, p < 0.001) and DSS rate (96.8 vs. 83.0%, p < 0.001) than patients underwent surgery alone. Patients receiving monotherapy (n = 130) had a relatively poor prognosis compared to patients receiving dual-drug (n = 66) without a significant difference (92.3 vs. 93.9%, p = 0.637). In patients without high-risk factors based on the Chinese Society of Clinical Oncology (CSCO) Guidelines, ACT also provided survival benefit (96.0 vs 82.9%, p = 0.038).

Conclusions: ACT was accompanied with higher 5-year OS and DSS rates of patients with pT2N0M0 gastric cancer. Patients with pT2N0M0 gastric cancer, regardless of high-risk factors based on the CSCO guidelines, might be considered candidates for ACT. In regard to the therapy regimen, monotherapy might be the optimal choice, considering the adverse events.

Adjuvant chemotherapy indications for stage I gastric cancer patients with negative lymph node

PURPOSE

Whether adjuvant chemotherapy (AC) has a survival benefit for pathological stage Ⅰ (T1N0 and T2N0) gastric cancer (GC) patients with negative lymph node (N0) remains controversial.

METHODS

Patients with surgically resected, histologically confirmed pT1N0 and pT2N0 GC between January 2011 and December 2017 at the National Cancer Center, China, were retrospectively reviewed.

RESULTS

A total of 1601 patients who met the inclusion criteria were identified. Independent risk factors for reduced overall survival (OS) identified in the Cox regression analysis were male sex (hazard ratio [HR] 1.454, 95% confidence interval [CI] 1.127-1.876), age ≥ 65 years (HR 1.367; 95% CI 1.071-1.744 ), T2 stage (HR 1.283; 95% CI 1.005-1.638), tumor size > 3 cm (HR 1.704; 95% CI 1.346-2.158), examined lymph nodes (EN) ≤ 15 (HR 1.327; 95% CI 1.058-1.664), and non-signet ring cell carcinoma (Non-SRCC) (HR 1.639; 95% CI 1.123-2.392). While only T2 stage (HR 1.410; 95% CI 1.026-1.936), tumor size > 3 cm (HR 1.755; 95% CI 1.285-2.397), examined lymph nodes (EN) ≤ 15 (HR 1.489; 95% CI 1.101-2.015) were independent risk factors for cause-specific survival (CSS). We divided patients with pT2N0 into four sub-categories according to two significant prognostic factors (size and EN) and found that only patient in group 3 (EN ≤ 15, size >3 cm) with improved CSS benefit from AC (p = 0.049). More significant CSS benefit from AC was identified in Non-SRCC patients within group 3 (p = 0.034).

CONCLUSION

An additional survival benefit related to AC is expected for selected pT2N0 patients. Non-SRCC patients with EN ≤ 15 and tumor size >3 cm may be particularly appropriate candidates for AC.

SPP1 Regulates Radiotherapy Sensitivity of Gastric Adenocarcinoma via the Wnt/Beta-Catenin Pathway

Purpose

Radiotherapy has been widely applied for the treatment of locally advanced and metastatic gastric adenocarcinoma (GAC). The aberrant expression of secreted phosphoprotein 1 (SPP1) is involved in radiosensitivity in a variety of cancers. The present study aims to characterize the clinical significance of SPP1 expression in GAC and its role and underlying mechanism of radiosensitivity.

Methods

The SPP1 expression in GAC tissues and pericarcinomatous tissues was determined by QRT-PCR and immunohistochemistry, and the SPP1 expression in GAC cell lines (BGC823, AGS, and SGC7901) and normal human gastric epithelial cell line (GES-1) was determined by western blot. T-test, one-way ANOVA, Cox regression model, and Kaplan–Meier plotter were applied to further assess the association between SPP1 expression and the prognosis of the patients with GAC. After irradiation and transfection with si-SPP1 combined with or without Wnt/β-catenin pathway inhibitor (XAV939), western blot, transwell, flow cytometry, and TOP-flash reporter assay were applied to detect DNA damage, invasion, apoptosis, cell cycle, and activation of Wnt/β-catenin pathway, respectively.

Results

SPP1 mRNA and protein levels in GAC tissues were both dramatically higher than those in pericarcinomatous tissues. SPP1 overexpression was positively associated with tumor size, nodal status, and histological grade of GAC patients. SPP1 overexpression, depth of invasion, and nodal status were independent prognostic factors for the patients. High SPP1 expression was negatively related to the overall survival in patients with GAC. We found that SPP1 knockdown enhanced the radiosensitivity of GAC cell lines (AGS and SGC7901). Increasing H2AX phosphorylation, apoptosis and G2/M phase arrest, and decreasing invasion were observed after the administration of si-SPP1 and irradiation. Radiosensitivity of SPP1 was mainly dependent on the Wnt/β-catenin signal pathway. XAV939 could enhance these phenomena induced by irradiation combined with SPP1 knockdown.

Conclusion

This study demonstrates that SPP1 suppresses Wnt/β-catenin signaling to enhance the radiosensitivity of GAC via inhibiting invasion and accelerating DNA damage, G2/M phase arrest, and apoptosis.

Challenges surrounding postoperative adjuvant chemotherapy for T2N0 gastric cancer

Determining the requirement for adjuvant chemotherapy in patients with stage IB gastric cancer (GC), and particularly for those with stage T2N0 (muscularis propria) disease, remains challenging. Patients with stage II/III disease benefit from postoperative adjuvant therapy; however, the randomized trials examining whether such therapy affords any survival benefit to patients with T2N0 disease are not sufficient. Current evidence suggests that not all patients with T2N0 disease should undergo such treatment, but only those with a high risk. To date, a number of retrospective studies have attempted to identify factors that are predictive of increased risk in an effort to guide adjuvant therapy-related clinical decision making. The National Comprehensive Cancer Network and the Chinese Society of Clinical Oncology have published guidelines regarding factors associated with increased patient risk. As a result, treatment decisions for patients with stage T2N0 disease are currently determined on an individualized basis, in light of risk factors and the potential benefits of treatment. The present review surveyed current evidence related to the treatment of patients with high-risk GC and highlighted the potential avenues for future investigated.

Comparative effectiveness of adjuvant chemoradiotherapy after gastrectomy among older patients with gastric adenocarcinoma: a SEER-Medicare study

BACKGROUND

Since the INT-0116 trial reported a survival advantage, postoperative chemoradiotherapy (CRT) has been a care standard for US patients in whom gastric adenocarcinoma has been diagnosed. We sought to estimate the association between treatment and survival among the older US Medicare population.

METHODS

This is a retrospective cohort study of Medicare beneficiaries aged 65-79 years with stage IB-III gastric adenocarcinoma diagnosed between 2002 and 2009 in a Surveillance, Epidemiology, and End Results region. Patients were categorized on the basis of treatment: (1) gastrectomy only and (2) gastrectomy plus adjuvant CRT. We examined factors associated with receipt of adjuvant CRT, including stage at diagnosis, comorbidity, and tumor subtype. Overall survival was measured from 90 days after gastrectomy until death or the censoring date of December 31, 2010.

RESULTS

Of the 1519 patients who underwent gastrectomy, 41.7% received adjuvant CRT. Factors associated with adjuvant CRT included age younger than 75 years at cancer diagnosis and stage II or stage III cancer. The median overall survival from the time of gastrectomy was 25.1 months (interquartile range 43.7 months) for gastrectomy only and 26.9 months (interquartile range 40.9 months) for adjuvant CRT. Multivariable and propensity-score-stratified models demonstrated a survival benefit associated with adjuvant CRT [hazard ratio (HR) 0.58; 95% confidence interval (CI) 0.50-0.67], although the magnitude was greater for stage II tumors (HR 0.50; 95% CI 0.39-0.61) and stage III tumors (HR 0.58; 95% CI 0.45-0.73) than for stage IB tumors (HR 1.02; 95% CI 0.71-1.45).

CONCLUSIONS

Adjuvant CRT, in conjunction with gastrectomy, was associated with a survival benefit among older patients with stage II or stage III tumors.

The role of adjuvant chemotherapy for patients with stage II and stage III gastric adenocarcinoma after surgery plus D2 lymph node dissection: a real-world observation

Background

The influence of adjuvant chemotherapy on the survival of gastric adenocarcinoma patients in a stage-specific manner is controversial.

Methods

To further explore this topic, we retrospectively analyzed the impact of adjuvant chemotherapy on the clinical outcomes of 77 stage II and 117 stage III patients diagnosed between January 2008 and December 2012.

Results

All 194 patients underwent radical operation plus D2 dissection, and were followed a median time of 23.3 (range 0.4–80.2) months. Median patient age was 67.7 (range 33.9–97.5) years. Adjuvant chemotherapy prolonged the relapse-free survival [22.9 (95 % confidence interval 9.4–36.4) vs. 14.2 (95 % CI 8.6–19.8) months, P = 0.009] and overall survival [32.3 (95 % CI 22.6–42.0) vs. 13.4 (95 % CI 9.5–17.2) months, P < 0.001] for patients with stage III, but not stage II, disease. Higher overall survival from adjuvant chemotherapy in stage II patients with node involvement did not reach the level of statistical significance (P = 0.102). To reduce the selection bias, 142 patients aged <75 years were included in a subgroup analysis in which the benefit of adjuvant chemotherapy on relapse-free survival and overall survival were demonstrated for patients with stage III disease.

Conclusions

Adjuvant chemotherapy prolongs relapse-free and overall survival for patients with stage III gastric cancer in a real-world situation. Tailoring therapy based on different characteristics for patients with stage II gastric cancer may produce better outcomes.

β-elemene enhances the radiosensitivity of gastric cancer cells by inhibiting Pak1 activation

AIM: To explore the potential of β-elemene as a radiosensitizer for gastric cancer cells and the underlying mechanisms.

METHODS: SGC7901, MKN45, MKN28, N87, and AGS human gastric cancer cell lines were used to screen for radioresistant gastric cancer cell lines. A 3-(4,5-dimeth-ylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay was used to determine the effects of β-elemene and IPA-3 on cell viability in MKN45 and SGC7901 gastric cancer cell lines. A clonogenic survival assay and annexin V-FITC/PI apoptosis detection assay were used to evaluate cellular radiosensitivity and radiation-induced cell death, respectively. A proteomic method, isobaric tags for relative and absolute quantitation (iTRAQ), was employed to screen the proteins regulated by β-elemene pretreatment prior to ionizing radiation (IR) in SGC7901 gastric cancer cell line. IPA-3 was used as a specific small molecule inhibitor of p21-activated protein kinase 1 (Pak1) to target Pak1 signaling. Protein levels of PAK1IP1 (p21-activated protein kinase-interacting protein 1), total Pak1 (t-Pak1), phospho-Pak1 (T423), phospho-ERK1/2 (Thr202/Tyr204), and cleaved caspase-3 (17 kDa) were assessed by western blotting.

RESULTS: MKN45 and SGC7901 gastric cancer cell lines were relatively more resistant to IR. β-elemene pretreatment decreased clonogenic survival following IR in MKN45 and SGC7901 gastric cancer cell lines. Additionally, β-elemene pretreatment prior to IR increased radiation-induced cell death compared with IR alone in MKN45 (10.4% ± 0.9% vs 34.8% ± 2.8%, P < 0.05) and SGC7901 (11.6% ± 0.9% vs 46.7% ± 5.2%, P < 0.05) human gastric cancer cell lines, respectively, consistent with the level of cleaved caspase-3 (17 kDa). Through iTRAQ analysis and western blot validation, we found that β-elemene upregulated PAK1IP1 and downregulated phospho-Pak1 (T423) and phospho-ERK1/2 in SGC7901 gastric cancer cells. IR increased the level of phospho-Pak1 (T423). Pretreatment with β-elemene decreased radiation-induced Pak1 and ERK1/2 phosphorylation. Inhibition of Pak1 using IPA-3 decreased clonogenic survival following IR. In addition, IPA-3 increased radiation-induced cell death in MKN45 (13.4% ± 0.3% vs 26.6% ± 1.0%, P < 0.05) and SGC7901 (16.0% ± 0.6% vs 37.3% ± 1.7%, P < 0.05) gastric cancer cell lines, respectively, consistent with the level of cleaved caspase-3 (17 kDa). Western blotting showed that IPA-3 decreased radiation-induced Pak1 and ERK1/2 phosphorylation.

CONCLUSION: This is the first demonstration that β-elemene enhances radiosensitivity of gastric cancer cells, and that the mechanism involves inhibition of Pak1 signaling.

Proton therapy in adjuvant treatment of gastric cancer: planning comparison with advanced x-ray therapy and feasibility report

BACKGROUND

Adjuvant chemoradiotherapy improves both overall- and relapse-free survival in patients with resected gastric cancer. However, this comes at the cost of increased treatment-related toxicity. Proton therapy (PT) has distinct dosimetric characteristics that may reduce dose to normal tissues, improving the therapeutic ratio. The purpose of this treatment planning study is to compare PT and intensity-modulated x-ray therapy (IMXT) in gastric cancer with regards to normal tissue sparing.

MATERIAL AND METHODS

The patient population consisted of resected gastric cancer patients treated at a single institution between 2008 and 2013. Patients who had undergone 4D CT simulation were replanned to the originally delivered doses (45-54 Gy in 25-30 daily fractions) using six-field photon IMXT and 2-3-field PT (double scattering-uniform scanning techniques).

RESULTS

Thirteen patients were eligible for the planning comparison. IMXT provided slightly higher homogeneity indices (median values 0.04 ± 0.01 vs. 0.07 ± 0.01, p = 0.03). PT resulted in significantly (p < 0.05) lower intermediate-low doses for all the normal tissues examined (small bowel V15 82 ml vs. 133 ml, liver mean doses Gy 11.9 vs. 14.4 Gy, left/right kidney mean doses 5/0.9 Gy vs. 7.8/3.1 Gy, heart mean doses 7.4 Gy vs. 9.5 Gy). The total energy deposited outside the target volume was significantly lower with PT (median integral dose 90.1 J vs. 129 J). Four patients were treated with PT: treatment was feasible and verifications scans showed that target coverage was robust.

CONCLUSION

PT can contribute to normal tissue sparing in the adjuvant treatment of gastric cancer, with a potential benefit in terms of compliance to treatment, acute and late toxicities.

Location, size, and distance: criteria for quality in esophagogastroduodenos copy reporting for pre-operative gastric cancer evaluation

BACKGROUND

There is a lack of existing literature regarding the quality of esophagogastroduodenoscopy (EGD) reporting for gastric cancer evaluation. This study aims to determine criteria for quality endoscopic evaluation of gastric cancer in North America by identifying important features of the EGD report for pre-operative evaluation of gastric cancer and assessing inclusion of these features in existing reports.

METHODS

Semi-structured interviews were conducted with experienced endoscopists from community and academic hospitals affiliated with the University of Toronto to identify essential elements for an EGD report. Then, 225 EGD reports from 2005 to 2008 were evaluated by two trained reviewers for inclusion of recommended EGD report elements and global assessment of report quality and adequacy for surgical planning.

RESULTS

Essential elements recommended by interviewed endoscopists include tumor size, location, and distance from gastroesophageal junction (GEJ). Approximately 95 % of all reports documented the location of lesions, <5 % documented distance from the GEJ, and <15 % documented tumor size. Overall report quality was rated as excellent for 4-5 % of reports; 20-42 % of all reports were deemed to be adequate for surgical planning. All surgeons interviewed as part of the endoscopist panel indicated that they would repeat the EGD before consulting with patients regarding surgical planning.

CONCLUSIONS

For pre-operative evaluation of gastric cancer, tumor size, location, and distance from key anatomical landmarks were proposed as essential elements of a quality EGD report. Most of the reviewed reports did not document these elements. Report quality is perceived to be poor and may lead to repeat endoscopy. Developing a standardized EGD reporting format based on inclusion of individual parameters can improve the quality of gastric cancer management.

Insights into cancer surveillance in Central and Eastern Europe, Israel and Turkey

The current cancer landscape within transitional economies in central and Eastern Europe and the Mediterranean area is not particularly optimistic. Current perceptions are often based on extrapolations from other countries and regions; and hence the authors collaborated with the South Eastern Europe Oncology Group (SEEROG) to collect information on cancer registration in Central and Eastern Europe, Israel and Turkey. Healthcare authorities and specialist oncology centres in 21 countries in the region were contacted for information on cancer registries in their countries. Based on this information, the authors believe that the recording and reporting of data on cancer in the region is at an acceptable level. The authors discuss and compare institution- and population-based registries, and present opinions on elements of an 'ideal registry' based on the survey replies and comparisons with other registries. A comparison with the sources used for GLOBOCAN 2008 illustrates the need for consistent data to be communicated, published and utilised throughout the region and the oncology community. The authors conclude by considering the potential value of collaboration between health authorities across the region, as well as between the clinical and epidemiological communities, to ensure that cancer data are consistently collected, verified and made public.

Population-based outcome of stage IA-IIA resected gastric adenocarcinoma: who should get adjuvant treatment?

BACKGROUND

The benefit of adjuvant treatment in gastric adenocarcinoma was demonstrated by randomized, controlled trials of patients with locally advanced tumors. Thus, its role for stage IIB-IIIC disease is widely accepted. We aimed to identify patients with stage IA-IIA gastric adenocarcinoma who have a poor prognosis and thus may benefit from adjuvant treatment.

METHODS

Patients with gastric adenocarcinoma who underwent surgical resection with pathological evaluation of ≥15 lymph nodes and had available disease-specific survival (DSS) data were identified from the Surveillance Epidemiology and End Results Registry. Survival differences were evaluated with the log-rank test and Cox multivariate analysis.

RESULTS

Stage and TN grouping strongly predicted DSS (P < 0.001, P < 0.001). Stage IA tumors had an excellent outcome: 91 ± 1.2 % 5-year DSS. The TN groupings of stages IB and IIA had the next best outcomes with 5-year DSS from 66 ± 4.6 % to 81 ± 2.3 %. Older age (P < 0.001), higher grade (P = 0.004), larger tumor size (P < 0.001), and proximal tumor location (P < 0.001) were independent predictors of worse DSS in stage IB-IIA tumors. We devised a risk stratification scheme for stage IB-IIA tumors where 1 point was assigned for age >60 years, tumor size >5 cm, proximal tumor location, and grade other than well-differentiated. Five-year DSS was 100 % for patients with 0 points; 86 ± 4.3 %, 1 point; 76 ± 3 %, 2 points; 72 ± 2.8 %, 3 points; and 48 ± 4.9 %, 4 points (P < 0.001).

CONCLUSIONS

Patients with stage IB-IIA gastric adenocarcinoma and ≥2 adverse features (age >60 years, tumor size >5 cm, proximal location, and high-grade) have 5-year DSS ≤76 %. Adjuvant therapy may be warranted for these patients.

Controversies and challenging therapeutic modalities in gastric cancer

Gastric cancer is still the fourth common neoplasm worldwide. Gastric ulcers, adenomatous polyps, and intestinal metaplasia have been associated with an increased relative risk. Tissue diagnosis and anatomic localization of the primary tumor are best obtained by upper gastrointestinal endoscopy. Despite new screening techniques peritoneal tumor spread and occult liver and lymph node metastases are only detected intra-operatively. Therapy is becoming more and more complex comprising surgical resection, investigational neoadjuvant, adjuvant or palliative chemotherapy, or supportive care. Complete surgical eradication of a tumor with resection of adjacent lymph nodes represents the best chance for long-term survival. The choice of operation depends upon the location of the tumor, the clinical stage, and the histologic type. Chemotherapy can provide symptom palliation, improve quality of life, and prolong survival in patients with advanced gastric cancer. Preoperative radiation therapy may allow for tumor downstaging and reduced probability of residual microscopic disease at surgery.

Adjuvant radiation therapy increases overall survival in node-positive gastric cancer patients with aggressive surgical resection and lymph node dissection: a SEER database analysis

OBJECTIVES

To determine the outcomes of postoperative radiation therapy on survival in gastric cancer.

METHODS

An analysis of patients with surgically resected and nonmetastatic gastric cancer from the Surveillance, Epidemiology, and End Results database from 1990 to 2003 was carried out. Survival curves were calculated according to the Kaplan-Meier method. Multivariate analysis was carried out by the Cox proportional hazard model.

RESULTS

We identified 11,630 patients who met inclusion criteria. Radiation therapy was associated with increased survival in patients with American Joint Committee on Cancer stage IB to IV. The median survival for stage IB and II patients treated with radiation was 96 months and 37 months, respectively, versus 56 months and 23 months for patients who did not receive adjuvant radiation (P=0.0281 for stage IB and <0.0001 for stage II). The 5-year overall survival for node-positive patients treated with radiation was 30.4% versus 21.4% for patients who did not receive adjuvant radiation (P<0.0001). The survival benefit of radiation therapy was maintained even if ≥15 lymph nodes were removed for N1 and N2 disease and if ≥30 lymph nodes were removed for N3 disease. For node-positive patients with ≥15 lymph nodes removed, adjuvant radiation was linked to increase survival in patients who underwent partial gastrectomy, total gastrectomy, and en bloc gastrectomy with other organs removed. Radiation was a strong independent factor for survival on multivariate analysis.

CONCLUSIONS

There is a correlation between survival and radiation therapy in node-positive gastric cancer patients and is independent of the extent of surgical resection and lymph node dissection.

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

PURPOSE

Surgical resection of gastric cancer has produced suboptimal survival despite multiple randomized trials that used postoperative chemotherapy or more aggressive surgical procedures. We performed a randomized phase III trial of postoperative radiochemotherapy in those at moderate risk of locoregional failure (LRF) following surgery. We originally reported results with 4-year median follow-up. This update, with a more than 10-year median follow-up, presents data on failure patterns and second malignancies and explores selected subset analyses.

PATIENTS AND METHODS

In all, 559 patients with primaries ≥ T3 and/or node-positive gastric cancer were randomly assigned to observation versus radiochemotherapy after R0 resection. Fluorouracil and leucovorin were administered before, during, and after radiotherapy. Radiotherapy was given to all LRF sites to a dose of 45 Gy.

RESULTS

Overall survival (OS) and relapse-free survival (RFS) data demonstrate continued strong benefit from postoperative radiochemotherapy. The hazard ratio (HR) for OS is 1.32 (95% CI, 1.10 to 1.60; P = .0046). The HR for RFS is 1.51 (95% CI, 1.25 to 1.83; P < .001). Adjuvant radiochemotherapy produced substantial reduction in both overall relapse and locoregional relapse. Second malignancies were observed in 21 patients with radiotherapy versus eight with observation (P = .21). Subset analyses show robust treatment benefit in most subsets, with the exception of patients with diffuse histology who exhibited minimal nonsignificant treatment effect.

CONCLUSION

Intergroup 0116 (INT-0116) demonstrates strong persistent benefit from adjuvant radiochemotherapy. Toxicities, including second malignancies, appear acceptable, given the magnitude of RFS and OS improvement. LRF reduction may account for the majority of overall relapse reduction. Adjuvant radiochemotherapy remains a rational standard therapy for curatively resected gastric cancer with primaries T3 or greater and/or positive nodes.

Postoperative chemotherapy in gastric cancer, consisting of etoposide, doxorubicin and cisplatin, followed by radiotherapy with concomitant cisplatin: A feasibility study

The prognosis following surgical treatment of gastric carcinoma (GC) or gastroesophageal junction (GEJ) adenocarcinoma remains poor. Although adjuvant chemo-radiotherapy with 5-fluorouracil has been shown to be beneficial, a high rate of distant failure has been reported. Thus, the toxicity profile and efficacy of an intensified chemo-radiotherapy regimen following complete or near-complete resection of GC was evaluated. Patients who underwent surgery for GC were eligible for evaluation. Treatment consisted of four cycles of modified EAP: etoposide 100 mg/m(2), days 1-3; cisplatin 27 mg/m(2), days 1-3; and adriamycin 40 mg/m(2), day 1; every 21 days, followed by a course of radiotherapy (45 Gy; 1.8 Gy/fr) combined with weekly cisplatin 40 mg/m(2). In total, 40 patients were included in the analysis. Median follow-up was 34 months from the onset of chemotherapy. Microscopic stage IV disease and/or R1 resection were found in 11 patients. For these patients, the median progression-free survival was 6.5 months, and overall survival 9.5 months, compared to 25 and 54 months, respectively, for the remaining 29 patients. In the latter subgroup, longer disease-free survival was associated with average dose intensity of >90% for the four cycles of EAP. The predominant grade 3-4 toxicities during EAP-chemotherapy were hematological adverse events. Nevertheless, the rate of severe non-hematologic toxicity reached 60%. There was one toxicity-related mortality. During the chemo-radiotherapy course, 39% of patients experienced grade 3-4 non-hematologic toxicities. It was concluded that the high toxicity rate of this regimen does not justify further evaluation of this postoperative protocol. Chemo-radiotherapy for R1 or pathological microscopic M1 patients does not appear to be justified.

Chemotherapy for operable gastric cancer: current perspectives

The majority of gastric cancer patients present with advanced, incurable disease and only a minority have localised disease that is suitable for radical treatment. A benefit has generally been demonstrated from adding chemotherapy to surgery for early disease though there are marked differences in how this is done globally. Whilst a perioperative approach, with chemotherapy given before and after gastric surgery is commonly used in the Europe and Australia most patients with operable gastric cancer in North America are treated with surgery and postoperative chemoradiation. In contrast, in East Asia, adjuvant fluoropyrimidine chemotherapy alone is used following D2 gastric resection surgery. However, despite the multimodality treatments, outcomes remain suboptimal as the majority of those treated for localised disease eventually relapse with incurable loco-regional or distant metastases. At the current time, an unmet need exists to further understand the biology of this aggressive disease and develop more efficacious therapies that can improve outcomes from this aggressive disease.

Adjuvant therapy for elderly patients with resected gastric adenocarcinoma: population-based practices and treatment effectiveness

BACKGROUND

A study was undertaken to determine the survival benefit of postoperative chemoradiation therapy for elderly patients with resected gastric adenocarcinoma.

METHODS

The authors identified 1023 individuals aged 65 years and older (median = 76) who underwent gastrectomy for nonmetastatic stage IB-IV gastric adenocarcinoma diagnosed between 2000 and 2002 in the linked Surveillance, Epidemiology, and End Results-Medicare database. They examined factors associated with receiving postoperative chemoradiation and analyzed the survival benefit associated with receiving postoperative chemoradiation.

RESULTS

Thirty percent of patients received adjuvant chemoradiation. On multivariate analysis, younger age (P < .0001), lymph node involvement (P < .0001), and more recent diagnosis (P = .0284) were associated with receiving chemoradiation. There was a trend toward increased use among patients with less comorbidity (P = .0515). The median follow-up was 25.5 months, and 62% died. On multivariate survival analysis, older patients (P < .0001) and those with lymph node involvement (P < .0001), T3 or T4 disease (P = .0472), higher grade disease (P = .0355), and more comorbidity (P = .0411) were more likely to die. After adjustment for other factors, receipt of adjuvant chemoradiation therapy did not significantly increase survival (hazard ratio, 0.90; 95% confidence interval, 0.72-1.12; P = .3453) and did not increase survival in a multivariate analysis that included propensity scores (P = .2090).

CONCLUSIONS

The authors did not detect a survival benefit, suggesting that some elderly patients with resected gastric adenocarcinoma may not gain a survival benefit from the administration of adjuvant chemoradiation. The analysis had limitations, and the results are hypothesis generating. Future gastric cancer trials should enroll more elderly patients and stratify patients by age to better understand the impact of treatment regimens on older patients.

Improved survival in patients with lymph node-positive gastric cancer who received preoperative radiation: an analysis of the Surveillance, Epidemiology, and End Results database

BACKGROUND

Several trials have been conducted to determine the feasibility of preoperative radiotherapy (RT) for gastric cancer. However, the absolute benefit from radiotherapy remains to be defined. In this study, the authors examined the use of preoperative RT (Pre-RT) and postoperative RT (PORT) in patients with gastric cancer from the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

The overall survival of patients who had nonmetastatic, resected gastric cancer between 2000 and 2006 was analyzed from the SEER database. Kaplan-Meier survival curves comparing Pre-RT, PORT, and no RT (No-RT) were analyzed using the log-rank test. A multivariate analysis (MVA) was conducted using Cox proportional hazards regression.

RESULTS

The authors identified 10,251 patients. There was no survival benefit for patients who received Pre-RT or PORT compared with No-RT patients for the entire cohort. Conversely, among lymph node-positive patients, there was a significant survival benefit from both Pre-RT and PORT compared with No-RT (log-rank test: PORT, P < .0001; Pre-RT, P = .0261). The median survival and 5-year overall survival among lymph node-positive patients were 22 months and 24%, respectively, for Pre-RT;29 months and 34%, respectively, for PORT; and 19 months and 20%, respectively, for No-RT. MVA demonstrated that Pre-RT, PORT, and removing ≥ 15 lymph nodes were independent predictors of improved survival, whereas tumor classification, lymph node status, tumor size, and tumor location were independent predictors of death.

CONCLUSIONS

The current results supported the use of Pre-RT in select patients with gastric cancer. However, additional trials will be needed to confirm these findings.

Does chemoradiotherapy improve outcomes for surgically resected adenocarcinoma of the stomach or esophagus?

BACKGROUND

To use a population-based registry to evaluate the effect of chemotherapy or radiation on survival for patients undergoing curative-intent surgery for adenocarcinoma of the esophagus or stomach.

METHODS

A linked data set between the Florida Cancer Data System and the Florida Agency for Health Care Administration from 1998 to 2003 was queried.

RESULTS

Overall, 3,378 patients underwent surgical extirpation with curative intent, 636 patients had esophageal adenocarcinoma (EAC), and 2,742 patients had gastric adenocarcinoma (GAC). Outcomes were adjusted for patient comorbidities and hospital teaching status. Overall, no benefit was observed for adjuvant therapies for EAC patients. A small improvement in survival was observed with adjuvant therapies for GAC. For localized EAC or GAC there was no additional survival benefit associated with adjuvant therapies. For patients with regional EAC, chemotherapy (20.0 vs. 13.0 months, P < .001) and radiation (18.6 vs. 13.5 months, P = .007) were associated with a statistically significant survival benefit. In multivariate analysis, independent predictors of improved survival for regional EAC include chemotherapy (hazard ratio [HR] .535, P < .001) and radiotherapy (HR .656, P = .01). For GAC, patients with regional disease showed an improved median survival with chemotherapy (21.1 vs. 11.2 months, P < .001) and radiotherapy (22.6 vs. 12.3 months, P < .001). In multivariate analysis, independent predictors of improved survival for regional GAC include chemotherapy (HR .629, P < .001) and radiation (HR .603, P < .001).

CONCLUSIONS

Patients with regional adenocarcinoma of the esophagus or stomach, but not those with localized disease, derive a statistically significant survival benefit from the addition of chemotherapy and radiation to surgical resection.

Use of adjuvant 5-fluorouracil and radiation therapy after gastric cancer resection among the elderly and impact on survival

PURPOSE

In randomized trials patients with resected nonmetastatic gastric cancer who received adjuvant chemotherapy and radiotherapy (chemoRT) had better survival than those who did not. We investigated the effectiveness of adjuvant chemoRT after gastric cancer resection in an elderly general population and its effects by stage.

METHODS AND MATERIALS

We identified individuals in the Surveillance, Epidemiology, and End Results-Medicare database aged 65 years or older with Stage IB through Stage IV (M0) gastric cancer, from 1991 to 2002, who underwent gastric resection, using multivariate modeling to analyze predictors of chemoRT use and survival.

RESULTS

Among 1,993 patients who received combined chemoRT or no adjuvant therapy after resection, having a later year of diagnosis, having a more advanced stage, being younger, being white, being married, and having fewer comorbidities were associated with combined treatment. Among 1,476 patients aged less than 85 years who survived more than 4 months, the 313 who received combined treatment had a lower mortality rate (hazard ratio, 0.83; 95% confidence interval, 0.71-0.98) than the 1,163 who received surgery alone. Adjuvant therapy significantly reduced the mortality rate for Stages III and IV (M0), trended toward improved survival for Stage II, and showed no benefit for Stage IB. We observed trends toward improved survival in all age categories except 80 to 85 years.

CONCLUSIONS

The association of combined adjuvant chemoRT with improved survival in an overall analysis of Stage IB through Stage IV (M0) resected gastric cancer is consistent with clinical trial results and suggests that, in an elderly population, adjuvant chemoradiotherapy is effective. However, our observational data suggest that adjuvant treatment may not be effective for Stage IB cancer, is possibly appropriate for Stage II, and shows significant survival benefits for Stages III and IV (M0) for those aged less than 80 years.