Meta-analysis of three randomized trials of capecitabine plus cisplatin (XP) versus S-1 plus cisplatin (SP) as first-line treatment for advanced gastric cancer

BACKGROUND

S-1 plus cisplatin (SP) and capecitabine plus cisplatin (XP) are standard first-line regimens for advanced gastric cancer (AGC) worldwide. We conducted a meta-analysis using individual participant data (IPD) to investigate which is more suitable.

METHODS

IPD from three randomized trials were collected. In these trials, patients with AGC were randomly allocated to SP (S-1 80-120 mg for 21 days plus cisplatin 60 mg/m2 (q5w)) or XP (capecitabine 2000 mg/m2 for 14 days plus cisplatin 80 mg/m2 (q3w)).

RESULTS

In 211 eligible patients, median overall survival (OS) for SP versus XP was 13.5 and 11.7 months (hazard ratio [HR], 0.787; p = 0.114), progression-free survival (PFS) was 6.2 and 5.1 months (HR, 0.767; P = 0.076), and TTF was 5.1 and 4.0 months (HR, 0.611; P = 0.001). The most common grade ≥ 3 adverse events with SP or XP were neutropenia (18% vs. 29%) and anorexia (16% vs.18%). Subgroup analysis demonstrated significant interaction between treatment effect and performance status > 1 (HR, 0.685; P = 0.036), measurable lesion (HR, 0.709; P = 0.049), primary upper third tumor (HR, 0.539; P = 0.040), and differentiated type (HR, 0.549; interaction, 0.236; P = 0.019). For the differentiated type, OS was significantly longer in the SP group (13.2 months) than in the XP group (11.1 months) (HR, 0.549; P = 0.019). For the undifferentiated type, OS was similar in the SP group (14.2 months) and in the XP group (12.4 months) (HR, 0.868; P = 0.476).

CONCLUSIONS

SP and XP were both effective and well tolerated. SP might be suitable for the pathological differentiated subtype of AGC.

CLINICAL TRIAL REGISTRATION

The HERBIS-2, HERBIS-4A, and XParTS II trials were registered with UMIN-CTR as UMIN000006105, UMIN000006755, and UMIN000006045, respectively.

Non-CpG sites preference in G:C > A:T transition of TP53 in gastric cancer of Eastern Europe (Poland, Romania and Hungary) compared to East Asian countries (China and Japan)

AIM

Mutation spectrum of TP53 in gastric cancer (GC) has been investigated world-widely, but a comparison of mutation spectrum among GCs from various regions in the world are still sparsely documented. In order to identify the difference of TP53 mutation spectrum in GCs in Eastern Europe and in East Asia, we sequenced TP53 in GCs from Eastern Europe, Lujiang (China), and Yokohama, Kanagawa (Japan) and identified the feature of TP53 mutations of GC in these regions.

SUBJECTS AND METHOD

In total, 689 tissue samples of GC were analyzed: 288 samples from East European populations (25 from Hungary, 71 from Poland and 192 from Romania), 268 from Yokohama, Kanagawa, Japan and 133 from Lujiang, Anhui province, China. DNA was extracted from FFPE tissue of Chinese, East European cases; and from frozen tissue of Japanese GCs. PCR products were direct-sequenced by Sanger method, and in ambiguous cases, PCR product was cloned and up to 8 clones were sequenced. We used No. NC_000017.11(hg38) as the reference sequence of TP53. Mutation patterns were categorized into nine groups: six base substitutions, insertion, deletion and deletion-insertion. Within G:C > A:T mutations the mutations in CpG and non-CpG sites were divided. The Cancer Genome Atlas data (TCGA, ver.R20, July, 2019) having somatic mutation list of GCs from Whites, Asians, and other ethnicities were used as a reference for our data.

RESULTS

The most frequent base substitutions were G:C > A:T transition in all the areas investigated. The G:C > A:T transition in non-CpG sites were prominent in East European GCs, compared with Asian ones. Mutation pattern from TCGA data revealed the same trend between GCs from White (TCGA category) vs Asian countries. Chinese and Japanese GCs showed higher ratio of G:C > A:T transition in CpG sites and A:T > G:C mutation was more prevalent in Asian countries.

CONCLUSION

The divergence in mutation spectrum of GC in different areas in the world may reflect various pathogeneses and etiologies of GC, region to region. Diversified mutation spectrum in GC in Eastern Europe may suggest GC in Europe has different carcinogenic pathway of those from Asia.

Histology Classification Highlights Differences in Efficacy of S-1 versus Capecitabine, in Combination with Cisplatin, for HER2-Negative Unresectable Advanced or Recurrent Gastric Cancer with Measurable Disease

It has been suggested that the therapeutic efficacy of S-1 + cisplatin (SP) and capecitabine + cisplatin (XP) may differ depending on the histology of the tumor, but no clear evidence exists. Individual participant data were obtained from three randomized phase II trials in which such patients received either SP (S-1 [40-60 mg twice daily for 21 days] plus cisplatin [60 mg/m² on day 8], every 5 weeks) or XP (capecitabine [1000 mg/m² twice daily for 14 days] plus cisplatin [80 mg/m² on day 1], every 3 weeks). A total of 162 patients were included, with 79 patients in the SP arm and 83 patients in the XP arm. Although there was also no difference between arms in ORR according to histological classification, differentiated tumors showed a significantly better OS (but not PFS) for SP versus XP that was associated with a deeper tumor shrinkage. Undifferentiated tumors showed a consistently better OS, and PFS for SP versus XP, likely because cases without tumor shrinkage tended to be fewer for SP. Our data thus showed that SP was superior to XP in this setting, but there were qualitative differences in therapeutic efficacy dependent on tumor histology.

Machine-learning model derived gene signature predictive of paclitaxel survival benefit in gastric cancer: results from the randomised phase III SAMIT trial

OBJECTIVE

To date, there are no predictive biomarkers to guide selection of patients with gastric cancer (GC) who benefit from paclitaxel. Stomach cancer Adjuvant Multi-Institutional group Trial (SAMIT) was a 2×2 factorial randomised phase III study in which patients with GC were randomised to Pac-S-1 (paclitaxel +S-1), Pac-UFT (paclitaxel +UFT), S-1 alone or UFT alone after curative surgery.

DESIGN

The primary objective of this study was to identify a gene signature that predicts survival benefit from paclitaxel chemotherapy in GC patients. SAMIT GC samples were profiled using a customised 476 gene NanoString panel. A random forest machine-learning model was applied on the NanoString profiles to develop a gene signature. An independent cohort of metastatic patients with GC treated with paclitaxel and ramucirumab (Pac-Ram) served as an external validation cohort.

RESULTS

From the SAMIT trial 499 samples were analysed in this study. From the Pac-S-1 training cohort, the random forest model generated a 19-gene signature assigning patients to two groups: Pac-Sensitive and Pac-Resistant. In the Pac-UFT validation cohort, Pac-Sensitive patients exhibited a significant improvement in disease free survival (DFS): 3-year DFS 66% vs 40% (HR 0.44, p=0.0029). There was no survival difference between Pac-Sensitive and Pac-Resistant in the UFT or S-1 alone arms, test of interaction p<0.001. In the external Pac-Ram validation cohort, the signature predicted benefit for Pac-Sensitive (median PFS 147 days vs 112 days, HR 0.48, p=0.022).

CONCLUSION

Using machine-learning techniques on one of the largest GC trials (SAMIT), we identify a gene signature representing the first predictive biomarker for paclitaxel benefit.

TRIAL REGISTRATION NUMBER

UMIN Clinical Trials Registry: C000000082 (SAMIT); ClinicalTrials.gov identifier, 02628951 (South Korean trial).

Preoperative risk factors for postoperative intra-abdominal infectious complication after gastrectomy for gastric cancer using a Japanese web-based nationwide database

BACKGROUND

Postoperative intra-abdominal infectious complication (PIIC) after gastrectomy for gastric cancer worsens in-hospital death or long-term survival. However, the methodology for PIIC preoperative risk assessment remains unestablished. We aimed to develop a preoperative risk model for postgastrectomy PIIC.

METHODS

We collected 183,936 patients' data on distal or total gastrectomy performed in 2013-2016 for gastric cancer from the Japanese National Clinical Database and divided into development (2013-2015; n = 140,558) and validation (2016; n = 43,378) cohort. The primary outcome was the incidence of PIIC. The risk model for PIIC was developed using 18 preoperative factors: age, sex, body mass index, activities of daily living, 12 comorbidity types, gastric cancer stage, and surgical procedure in the development cohort. Secondarily, we developed another model based on the new scoring system for clinical use using selected factors.

RESULTS

The overall incidence of PIIC was 4.7%, including 2.6%, 1.7%, and 1.3% in anastomotic leakage, pancreatic fistula, and intra-abdominal abscess, respectively. Among the 18 preoperative factors, male [odds ratio, (OR) 1.92], obesity (OR, 1.52-1.96), peripheral vascular disease (OR, 1.55), steroid use (OR, 1.83), and total gastrectomy (OR, 1.89) strongly correlated with PIIC incidence. The entire model using the 18 factors had good discrimination and calibration in the validation cohort. We selected eight relevant factors to create a simple scoring system, using which we categorized the patients into three risk groups, which showed good calibration.

CONCLUSION

Using nationwide clinical practice data, we created a preoperative risk model for postgastrectomy PIIC for gastric cancer.

Biomarker analysis to predict the pathological response to neoadjuvant chemotherapy in locally advanced gastric cancer: An exploratory biomarker study of COMPASS, a randomized phase II trial

Background: The findings of COMPASS, a randomized phase II study, suggested that the regimens and courses of neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer (GC) did not affect the pathological response. However, pathological complete response was achieved in 10% patients who received four courses of either S-1/cisplatin or paclitaxel/cisplatin. We hypothesized that if relevant biomarkers could be used to predict the suitable NAC regimen before treatment initiation, further improvements could be ensured in the outcomes of locally advanced GC.

Materials and Methods: mRNA extraction, real-time polymerase chain reaction, and immunohistochemical analyses were performed using endoscopic biopsy specimens of primary tumors, collected prior to NAC, to determine the clinically relevant biomarkers.

Results: TIMP1, DSG2, RRM1, MUC2, EGFR, ZDHHC14, and CLDN18.2 were identified as biomarker candidates, since their expression was significantly associated with the pathological responses to each NAC regimen. Furthermore, TIMP1 and DSG2 were identified as predictive biomarkers of the pathological response to each NAC regimen.

Conclusions: The effective prediction of the pathological response to NAC regimens in locally advanced GC using biomarkers identified from endoscopic biopsy specimens indicates the possibility of personalizing NAC based on biomarker analysis.

Differences in disease status between patients with progression after first-line chemotherapy versus early relapse after adjuvant chemotherapy who undergo second-line chemotherapy for gastric cancer: Exploratory analysis of the randomized phase III TRICS trial

BACKGROUND

Second-line chemotherapy (SLC) improves survival in advanced gastric cancer (AGC). Patients receiving SLC are categorized into two disease status groups: tumour progression after first-line chemotherapy and early recurrence after adjuvant chemotherapy. Differences between these groups have not yet been clarified.

PATIENTS AND METHODS

A total of 163 eligible patients registered in the randomized phase III TRICS trial evaluating SLC for patients with AGC was classified into the progressive disease (PD) group (n = 55) or the early relapse (ER) group (n = 108). We compared overall survival (OS), progression-free survival (PFS), overall response rate (ORR), and safety. Adjusted OS and adjusted PFS were estimated using inverse probability of treatment weighting (IPTW).

RESULTS

The ER group had a lower median age than the PD group (66 vs. 72 years; P = 0.016), performance status (PS) 0 was more frequently seen in the ER group (87% vs. 71%; P = 0.012). The adjusted median OS was 13.7 months in the ER group and 13.6 months in the PD group (IPTW hazard ratio [HR]: 1.023; P = 0.854). The adjusted median PFS was 4.9 months in the ER group and 4.4 months in the PD group (IPTW HR: 0.707; P = 0.004). ORR was significantly better in the ER group than the PD group (21.3% vs. 4.9%; P = 0.020). No significant differences were observed in the incidence of adverse events.

CONCLUSIONS

ER was associated with improved PFS and better ORR than PD, although no difference in survival was demonstrated. From the viewpoint of treatment outcome, it seems appropriate to treat patients with ER in the same way as patients with PD.

CLINICAL TRIAL REGISTRATION

UMIN 000002571.

Current status of perioperative chemotherapy for locally advanced gastric cancer and JCOG perspectives

Perioperative treatment for locally advanced gastric cancer has been inconsistent between Japan and the Western countries. In Japan, D2 gastrectomy followed by adjuvant chemotherapy is regarded as standard treatment, while neoadjuvant or perioperative chemotherapy is considered to be a standard in the Western countries. Stomach Cancer Study Group of Japan Clinical Oncology Group (JCOG) has conducted many perioperative chemotherapy trials. After the publishing of positive results of ACTS-GC trial, stage-specific adjuvant chemotherapy protocols are planned. JCOG1104 was conducted as to demonstrate the non-inferiority of four courses of S-1 to standard eight courses of S-1, because the efficacy of S-1 appears to be sufficient in stage II. The trial failed to demonstrate the non-inferiority of four courses of S-1. S-1 for 1 year is still recognized to be a standard for stage II gastric cancer. For stage III, studies with more intensive treatments were planned as the efficacy of S-1 monotherapy seems to be insufficient. As in the Western countries, JCOG planned the perioperative chemotherapy. However, the clinical staging is a serious issue to select optimal patients for perioperative chemotherapy. JCOG conducted a prospective cohort study to evaluate the validity of clinical staging in JCOG1302A. From the results of this study, cT3-4 and cN1-3 are selected as optimal candidate for perioperative chemotherapy. JCOG1509 was conducted to demonstrate the superiority of perioperative chemotherapy to adjuvant chemotherapy in these cohorts. Perioperative chemotherapy for marginally resectable tumours such as linitis plastica or extensive nodal disease and special type of cancer like HER2 positive are also conducted.

Meta-analysis of two randomized phase III trials (TCOG GI-0801 and ECRIN TRICS) of biweekly irinotecan plus cisplatin versus irinotecan alone as second-line treatment for advanced gastric cancer

BACKGROUND

Biweekly irinotecan (CPT-11) plus cisplatin (CDDP) combination (BIRIP) and CPT-11 alone are both expectable options for treating advanced gastric cancer (AGC) in a second-line setting. We conducted a meta-analysis to compare the efficacy and safety of these two regimens in patients enrolled two randomized phase III trials.

PATIENTS AND METHODS

Individual patient-level data from two randomized phase III trials were collected for this study. In both trials, patients with AGC refractory to S-1-based chemotherapy were randomly allocated to BIRIP (CPT-11, 60 mg/m²; CDDP, 30 mg/m², q2w) or to CPT-11 (150 mg/m², q2w).

RESULTS

Cumulative data from 290 eligible patients were evaluated. The OS was 12.3 months [95% confidence interval (CI) 10.5-14.1] in the BIRIP group and 11.3 months (95% CI 10.0-13.2) in the CPT-11 group (hazard ratio 0.87; 95% CI 0.68-1.12, P = 0.272), while PFS was significantly longer in the BIRIP group (4.3 months [95% CI 3.5-5.1]) than in the CPT-11 group (3.3 months [2.9-4.1]; HR 0.77; 95% CI 0.61-0.98, P = 0.035). The response rate was 20.5% in the BIRIP group and 16.0% in the CPT-11 group (P = 0.361). However, the disease control rate was significantly better in the BIRIP group (72.1%) than in the CPT-11 group (59.2%) (P = 0.032). The two groups did not differ significantly in the incidences of grade 3 or worse adverse events.

CONCLUSIONS

Both BIRIP and CPT-11 may be good therapeutic options for patients with AGC as second-line treatment.

CLINICAL TRIAL REGISTRATION

UMIN 000025367.

An integrated analysis of two phase II trials (JCOG0001 and JCOG0405) of preoperative chemotherapy followed by D3 gastrectomy for gastric cancer with extensive lymph node metastasis

BACKGROUND

Gastric cancer with extensive lymph node metastasis is commonly regarded as unresectable, while preoperative chemotherapy followed by gastrectomy has been tested since 2000 in JCOG (JCOG0001 and JCOG0405). The survivals were quite different between the trials despite the similar eligibility criteria. The aim of this study was to investigate if survival is still better in JCOG0405 after adjusting baseline factors and if there is any subset of patients who benefit more from either treatment.

METHODS

Eligibility criteria for both trials included histologically proven gastric adenocarcinoma; bulky nodal involvement around the celiac artery and its major branches (bulky N) and/or para-aortic lymph node (PAN); cM0 (except PAN); negative lavage cytology; not linitis plastica type; PS of 0 or 1. Patients received two or three cycles of preoperative chemotherapy of irinotecan plus cisplatin in JCOG0001, or S-1 plus cisplatin in JCOG0405, followed by D3 gastrectomy. Multivariable analysis for overall survival adjusting baseline and treatment factors was performed with the Cox regression model.

RESULTS

After adjusting baseline factors, S-1 plus cisplatin was superior to irinotecan plus cisplatin for overall survival (HR = 0.39: 95% CI 0.22-0.67). The 5-year overall survival was poor for patients with bulky N+/PAN+ (19.2%) compared with bulky N+/PAN- (50.7%) or bulky N-/PAN+ (43.5%).

CONCLUSIONS

S-1 plus cisplatin was shown to be a favorable preoperative treatment for gastric cancer with extensive lymph node metastasis by multivariable analysis, while poor prognosis in patients having both bulky N+ and PAN+ may necessitate further treatment improvement.

Comprehensive biomarker analyses identifies HER2, EGFR, MET RNA expression and thymidylate synthase 5'UTR SNP as predictors of benefit from S-1 adjuvant chemotherapy in Japanese patients with stage II/III gastric cancer

Purpose: A comprehensive molecular analysis was conducted to identify prognostic and predictive markers for adjuvant S-1 chemotherapy in stage II/III Japanese gastric cancer (GC) patients and to evaluate their potential suitability for alternative cytotoxic or targeted drugs.

Experimental Design: We investigated genetic polymorphisms of enzymes potentially involved in 5-fluoruracil (5-FU) metabolism as well as platinum resistance, previously identified genomic subtypes potentially predicting 5-FU benefit, and mRNA expression levels of receptor tyrosine kinases and KRAS as potential treatment targets in a single institution cohort of 252 stage II/III GC patients treated with or without S-1 after D2 gastrectomy.

Results: 88% and 62% GC had a potentially 5-FU sensitive phenotype by SNP analyses of TS 3'UTR, and TS 5'UTR, respectively. 24%, 46%, 40%, 5%, and 44% GC had a potentially platinum sensitive phenotype by SNP analyses of GSTP1, ERCC1 rs11615, ERCC1 rs3212986, ERCC2, and XRCC1, respectively. High HER2, EGFR, FGFR2, or MET mRNA expression was observed in 49%, 66%, 72%, and 54% GC, respectively. High HER2 expression was the only significant prognosticator (HR=3.912, 95%CI: 1.706-8.973, p=0.0005). High HER2 (p=0.031), low EGFR (p=0.124), high MET (p=0.165) RNA expression, and TS 5'UTR subtype 2R/2R, 2R/3C, or 3C (p=0.058) were significant independent predictors for S-1 resistance.

Conclusions: The present study suggests that platinum-based or RTK targeted agents could be alternative treatment options for a substantial subgroup of Japanese GC patients currently treated with S-1. HER2, EGFR, MET, and TS 5'UTR SNP appear to be promising predictive markers for S-1 resistance warranting validation in an independent GC series.

Development and validation of grade-based prediction models for postoperative morbidity in gastric cancer resection using a Japanese web-based nationwide registry

AIM

Gastric cancer is the second leading cause of cancer death worldwide. Surgery is the mainstay treatment for gastric cancer. There are no prediction models that examine the severity of postoperative morbidity. Herein, we constructed prediction models that analyze the risk for postoperative morbidity based on severity.

METHODS

Perioperative data were retrieved from the National Clinical Database in patients who underwent elective gastric cancer resection between 2011 and 2012 in Japan. Severity of postoperative complications was determined by Clavien-Dindo classification. Patients were randomly divided into two groups, the development set and the validation set. Logistic regression analysis was used to build prediction models. Calibration powers of the models were assessed by a calibration plot in which linearity between the observed and predicted event rates in 10 risk bands was assessed by the Pearson R 2 statistic.

RESULTS

We obtained 154 278 patients for the analysis. Prediction models were constructed for grade ≥2, grade ≥3, grade ≥4, and grade 5 in the development set (n = 77 423). Calibration plots of these models showed significant linearity in the validation set (n = 76 855): R 2 = 0.995 for grade ≥2, R 2 = 0.997 for grade ≥3, R 2 = 0.998 for grade ≥4, and R 2 = 0.997 for grade 5 (all: P < 0.001).

CONCLUSION

Prediction models for postoperative morbidity based on grade will provide a comprehensive risk of surgery. These models may be useful for informed consent and surgical decision-making.

Detection of atypical data in multicenter clinical trials using unsupervised statistical monitoring

BACKGROUND/AIMS

A risk-based approach to clinical research may include a central statistical assessment of data quality. We investigated the operating characteristics of unsupervised statistical monitoring aimed at detecting atypical data in multicenter experiments. The approach is premised on the assumption that, save for random fluctuations and natural variations, data coming from all centers should be comparable and statistically consistent. Unsupervised statistical monitoring consists of performing as many statistical tests as possible on all trial data, in order to detect centers whose data are inconsistent with data from other centers.

METHODS

We conducted simulations using data from a large multicenter trial conducted in Japan for patients with advanced gastric cancer. The actual trial data were contaminated in computer simulations for varying percentages of centers, percentages of patients modified within each center and numbers and types of modified variables. The unsupervised statistical monitoring software was run by a blinded team on the contaminated data sets, with the purpose of detecting the centers with contaminated data. The operating characteristics (sensitivity, specificity and Youden's J-index) were calculated for three detection methods: one using the p-values of individual statistical tests after adjustment for multiplicity, one using a summary of all p-values for a given center, called the Data Inconsistency Score, and one using both of these methods.

RESULTS

The operating characteristics of the three methods were satisfactory in situations of data contamination likely to occur in practice, specifically when a single or a few centers were contaminated. As expected, the sensitivity increased for increasing proportions of patients and increasing numbers of variables contaminated. The three methods showed a specificity better than 93% in all scenarios of contamination. The method based on the Data Inconsistency Score and individual p-values adjusted for multiplicity generally had slightly higher sensitivity at the expense of a slightly lower specificity.

CONCLUSIONS

The use of brute force (a computer-intensive approach that generates large numbers of statistical tests) is an effective way to check data quality in multicenter clinical trials. It can provide a cost-effective complement to other data-management and monitoring techniques.

Identification of a high-risk subtype of intestinal-type Japanese gastric cancer by quantitative measurement of the luminal tumor proportion

Background

We hypothesized that the relative proportion of tumor (PoT) at the luminal surface can predict gastric cancer (GC) patient survival.

Methods

We measured the luminal PoT in resection specimens from 231 GC patients with stage II/III disease who had surgery at the Kanagawa Cancer Center, Yokohama, Japan. Tissue microarrays were used to assess the extent of immune cell infiltration by CD45 immunohistochemistry. Results were related to histopathological features and patient overall survival (OS).

Results

PoT was significantly lower in diffuse‐type (30%) compared to intestinal‐type GC (41%), P = 0.03. Patients with low PoT intestinal‐type GC survived significantly longer than patients with high PoT intestinal‐type GC (5 years OS: 78% vs 47%, P = 0.0112). Low PoT was an independent favorable prognostic factor in multivariate analysis in intestinal‐type GC. Low PoT was correlated with high content of CD45‐positive immune cells (P = 0.035). There was no relationship between PoT and survival in diffuse‐type GC.

Conclusions

This is the first study to identify a subgroup of patients with stage II/III intestinal‐type GC at high risk of recurrence by measuring PoT at the luminal surface. The relationship between PoT and immune cell content provides an initial insight into potential underlying biological mechanisms.

The clinical impact of Hangeshashinto (TJ-14) in the treatment of chemotherapy-induced oral mucositis in gastric cancer and colorectal cancer: Analyses of pooled data from two phase II randomized clinical trials (HANGESHA-G and HANGESHA-C)

Background: The current pooled analysis evaluated the efficacy of Hangeshashinto (TJ-14) in the prevention and/or treatment of chemotherapy-induced oral mucositis (COM) in gastric cancer and colorectal cancer using two prospective, multi-institutional, randomized, double-blind, placebo-controlled phase II trials.

Patients and Methods: HANGESHA-G and HANGESHA-C randomly assigned patients with gastric cancer or colorectal cancer who developed moderate to severe COM (grade ≥1) during any cycle of chemotherapy to receive either TJ-14 or a placebo as a double-blind trial. The patients received a placebo or TJ-14 for four to six weeks, according to the chemotherapy regimen, from the start of their next course of chemotherapy. The primary endpoint was the incidence of grade ≥2 COM in the protocol treatment course, and the secondary endpoints were the time to disappearance of COM and the incidence of adverse events.

Results: The pooled population included 181 patients. The incidence of grade ≥2 COM in the TJ-14 group was 55.7% (49 patients), while that in the placebo group was 53.8% (50 patients); there was no significant difference between the two groups (p=0.796). The median time to remission of grade ≥2 COM to grade <1 was 8 days in the TJ-14 group and 15 days in the placebo group (p= 0.072). The hazard ratio was 1.54 [1.02 to 2.31] in favor of TJ-14. Treatment with TJ-14 was associated with marginally significant reduction in the duration of severe grade ≥2 COM in comparison to patients receiving placebo indicating the effect of TJ-14 in reducing the severity of COM.

Conclusion: The present-pooled analysis showed that TJ-14 had a treatment effect in gastric cancer and colorectal cancer patients with COM in comparison to a placebo. Further phase III studies with a larger sample size are needed to clarify the protective effects of TJ-14 against COM.

Alterations of plasma glutamine and surgical stress in gastric cancer surgery

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Background: The plasma glutamine levels are known to decrease after major surgery, which is related to a negative clinical outcome. However, the influence of surgical stress on the decrease in the plasma glutamine concentration is unclear. The aim of this study was to evaluate the change in glutamine in relation to the types of gastrectomy and approaches as well as the amount of surgical stress evaluated by serum interleukin-6(IL-6) as an objective indicator. Methods: This was a prospective observational study. The eligibility criteria were (1) gastric adenocarcinoma of the stomach confirmed by pathology and (2) patients scheduled to receive gastrectomy with D1 or D2 lymphadenectomy for gastric cancer. Blood samples were taken at 7 AM on the day of surgery and at 12 h after surgery to measure the plasma glutamine and interleukin-6 (IL-6) levels. Results: Between May 2011 and December 2011, 81 consecutive patients were enrolled in this study. The plasma glutamine level was significantly decreased in all patients, regardless of distal or total gastrectomy and laparoscopic or open surgery. No significant differences were observed in the IL-6 level between total and distal gastrectomy patients or between patients treated via a laparoscopic or open approach. Decreases in the plasma glutamine level were positively correlated with the logarithmically transformed-plasma IL-6 (logIL6) (r = 0.471, p < 0.001) overall. Conclusions: Decreases in the glutamine concentration depended on the amount of surgical stress. When conducting a clinical trial to evaluate glutamine administration, personalized adjustment may be key to avoiding glutamine depletion in response to surgical stress.

Survival of second-line irinotecan-based chemotherapy in early relapse patients with gastric cancer after adjuvant chemotherapy: Exploratory subgroup analysis of TRICS trial

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Background: Second-line chemotherapy (SLC) was reported to improve the survival of advanced gastric cancer (AGC). The TRICS trial which a randomized phase III study of second-line irinotecan plus cisplatin versus irinotecan alone in patients with AGC refractory to S-1 monotherapy, revealed that both irinotecan based chemotherapies were effective with favorable long-term survivals and generally well tolerated. Eligible patients included patients with recurrence within 6 months after the completion of adjuvant therapy with S-1 (early relapse cases), or patients with tumor progression after first-line S-1 for an advanced cancer (progressive cases), in this trial. However, it is unclear whether survivals in early relapse cases were different from these in progressive cases or not. Methods: A total of 168 patients registered to the TRICS trial were classified as early relapse group (n = 111) or progressive group (n = 57), and 168 (irinotecan plus cisplatin, early relapse 56/83, 67%; irinotecan alone, 55/85, 65%) and 163 (55/81, 68%; 53/82, 65%) patients were analyzed for survival. Adjusted OS and adjusted PFS were constructed adjusted Kaplan-Meier curve with inverse probability weight, and were estimated by inverse probability of treatment weighting method (IPTW). Results: In baseline characteristics, PS 0 were more frequently seen in early relapse group than in progressive group (86% vs 72%, p = 0.0328), and median age of early relapse group was younger than progressive group (66 vs 72, p = 0.0162). The median OS was 13.9 months in early relapse group and 10.0 months in progressive group (HR:0.746, p = 0.1019). The adjusted median OS was 14.0 months in early relapse group and 10.6 months in progressive group (IPTW HR:0.864, p = 0.1019). Early relapse group showed better trends in PFS compared to the progressive group (4.7M vs 3.6M, HR: 0.650, p = 0.0149). The adjusted median PFS was 4.8 months in early relapse group and 3.7 months in progressive group (IPTW HR:0.673, p = 0.0008). Conclusions: Irinotecan based chemotherapies were effective especially in early relapse cases after adjuvant therapy with S-1, in second-line setting of AGC.

Abstract A042: Genomic predictors of chemotherapy efficacy in gastric cancer in the GC0301/TOP002 phase III trial

Recent gastric cancer (GC) clinical trials have aimed to establish the efficacy of combination therapy over monotherapy; however, a role for genomic biomarkers in these trials has remained largely unexplored. Here, using the NanoString expression platform, we analyzed 105 gastric tumors from a randomized phase III Japanese clinical trial (GC0301/TOP002) testing efficacy of irinotecan plus S-1 over S-1 chemotherapy. We found that previously established proliferative subtype signatures were associated with older patients (&gt;65 years) and liver metastasis, while mesenchymal subtype signatures were associated with younger patients (≤65 years) and peritoneal metastasis. Genes associated with the tumor microenvironment (CD14, DPYD), oncogenic signaling (Wnt5A, PTRF), and chemokines (CCL5, CXCL12, CCL19) were significantly associated with patient age, Lauren’s histologic classification, tumor status, measurable lesions, and metastasis. We identified Wnt5A downregulation as a candidate predictor of improved progression-free survival (PFS) (&gt;8 weeks) in fluorouracil (S-1) monotherapy-treated patients, but not in irinotecan plus S-1 (IRI-S) combined treatment. Although not achieving statistical significance, we observed a trend for mesenchymal subtype showing a treatment interaction with IRI-S for efficacy. These findings highlight promising genomic markers that could be useful predictors of chemotherapy efficacy for better prognosis and survival outcome in gastric cancer.

Citation Format: Kakoli Das, Masataka Taguri, Akira Tsuburaya, Patrick Tan. Genomic predictors of chemotherapy efficacy in gastric cancer in the GC0301/TOP002 phase III trial [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A042.

Genomic predictors of chemotherapy efficacy in advanced or recurrent gastric cancer in the GC0301/TOP002 phase III clinical trial

Recent gastric cancer clinical trials have aimed to establish the efficacy of combination therapy over monotherapy, however, the role for genomic biomarkers in these trials has remained largely unexplored. Here, using the NanoString expression platform, we analyzed 105 gastric tumors from a randomized phase III Japanese clinical trial (GC0301/TOP002) testing the efficacy of irinotecan plus S-1(IRI-S) versus S-1 therapy. We found that previously established proliferative subtype signatures, were associated with older patients (>65 years) and liver metastasis while mesenchymal subtype signatures were associated with younger patients (≤65 years) and peritoneal metastasis. Genes associated with tumor microenvironment (CD4, CD14, ADAMTS1, CCL5, CXCL12, CCL19), therapeutic implications (DPYD) and oncogenic signaling (Wnt5A, PTRF) were significantly associated with patient age, histology, tumor status, measurable lesions and metastasis. We identified Wnt5A downregulation as a candidate predictor of improved progression free survival (>8 weeks) in S-1 but not in IRI-S treatment. Although statistical significance was not achieved, mesenchymal subtype showed a trend for treatment interaction with IRI-S for efficacy. These findings highlight promising genomic markers that could be useful predictors of chemotherapy efficacy for better prognosis and survival outcome in gastric cancer.

Usefulness of Surgical Apgar Score on Predicting Survival After Surgery for Gastric Cancer

BACKGROUND

Complete surgical resection is essential for a cure for most gastric cancer. Recently it was reported that surgical Apgar score (SAS) can predict postoperative complication and that postoperative complication is associated with poor long-term survival. The aim of this study is to assess whether SAS can predict overall survival (OS) after surgery for gastric cancer.

METHODS

We retrospectively compared clinicopathological characteristics and survival between high and low SAS score groups in patients who underwent gastrectomy for gastric cancer.

RESULTS

Low-scored SAS group (group L) was significantly more common among ASA-PS 2, open approach, total gastrectomy, D2 lymph node dissection, postoperative complication grade 2-4, deep tumor invasion, lymph node metastases, and advanced pathological TNM stage than high-scored SAS group (group H). The 5-year OS of group H and group L were 81.6 and 55.9 %, respectively (p < .001); OS of group L tended to be poorer than that of group H in stage III patients (p = .060) and in stage IV patients (p < .001). In multivariate analysis, pathological stage and SAS were identified as independent predictors for OS.

CONCLUSIONS

SAS is useful for predicting survival after surgery for gastric cancer.

Surgical advantages of reduced-port laparoscopic gastrectomy in gastric cancer

BACKGROUND

Although a few studies have reported the use of reduced-port laparoscopic gastrectomy (RPG) in gastric cancer patients, the feasibility of routinely using this technique remains unclear. It is therefore important to evaluate the surgical advantages of this technique in this patient group.

METHODS

Between August 2010 and July 2015, 165 patients underwent RPGs at our hospital, performed by a single surgeon. Of these patients, 88 underwent reduced-port laparoscopic distal gastrectomy (RPLDG) and 77 underwent reduced-port laparoscopic total gastrectomy (RPLTG). In addition to short-term surgical outcomes after RPG, survival times and the surgical learning curve were also evaluated.

RESULTS

Blood losses during lymph node dissection in the RPLDG and RPLTG groups were not significantly different (p = 0.160). Conversion to open surgery was necessary in only two patients. Postoperative morbidities were observed in 14.8 % of the RPLDG group and 14.3 % of the RPLTG group, but there were no deaths. Most patients expressed high cosmetic satisfaction in both groups. In the RPLDG group, operation time during reconstruction decreased over the first 50 cases and then plateaued, as the surgeon's experience of the technique increased. In contrast, in the RPLTG group, operation times dropped with surgical experience for both lymph node dissection, plateauing after 40 cases, and for reconstruction, plateauing after 30 cases. Only three patients died of gastric cancer in the follow-up period and three patients died of other diseases. Five-year overall survival and 5-year disease-specific survival were 95.6 and 98.0 %, respectively.

CONCLUSIONS

We have shown that reduced-port gastrectomy (RPG) could be an acceptable and satisfactory procedure for treating gastric cancer for an experienced laparoscopic gastric surgeon who has sufficient previous experience of conventional laparoscopic gastrectomies.

Feasibility and Safety of Transhiatal Approach and D2 Total Gastrectomy after Neoadjuvant Chemotherapy for Adenocarcinoma of the Esophago-Gastric Junction: A Subset Analysis of the COMPASS Trial

BACKGROUND

It was unclear whether the transhiatal approach and D2 total gastrectomy after neoadjuvant chemotherapy (NAC) for adenocarcinoma of the esophago-gastric (AEG) junction are as feasible and safe as D2 gastrectomy following NAC.

PATIENTS AND METHODS

We clarified the short-term surgical results in AEG and non-AEG patients in a subset analysis of the COMPASS trial.

RESULTS

Eighty-three patients, 24 with AEG and 59 with non-AEG, were registered in the study. Among 24 patients with AEG, 5 were classified to have Siewert type I, 11 to have type II and 8 to have type III. The tumor progression, completion of NAC, and clinical and pathological responses were similar between the groups. Twenty-four AEG and 51 non-AEG patients proceeded to surgery. The extent of dissection (D1/D2) was 3/21 in the AEG and 3/48 in the non-AEG patients. The R0 resection rate was 69% in the non-AEG and 88% in the AEG patients. Neither grade 3b/4 morbidity nor surgical mortality was observed in either group.

CONCLUSIONS

The transhiatal approach and D2 total gastrectomy after NAC seem to be as safe and feasible as D2 gastrectomy for non-AEG cancer.

[A Case of Resected Advanced Gastric Cancer Exhibiting Pathological Complete Response after Neoadjuvant Che-motherapy(DTX/CDDP/S-1:DCS)]

A 71-year-old man was diagnosed with gastric cancer (LM, Less, type 2, T4aN2M0, cStageⅢb). A diagnostic laparoscopic surgery revealed serosal invasion without peritoneal dissemination. Two courses of neoadjuvant chemotherapy (NAC) for locally advanced gastric cancer using DCS (DTX: 20 mg/m2 on day 1, CDDP: 50 mg/m2 on day 1, S-1: 120 mg/day, twice a day on days 1-14) was performed, which resulted in a clinical partial response. Consequently, distal gastrectomy with D2 lymph node dissection, and BillrothⅠreconstruction were carried out. Histopathological examination revealed no residual cancer cells both in the primary lesion and in the lymph nodes, indicating a pathological complete response (grade 3). Six courses of S-1 (120 mg/day on days 1-28, followed by 2 weeks of rest) were administered as adjuvant chemotherapy. At the 2 years 10 months follow-up after adjuvant therapy, the patient has had no recurrence. Combination chemotherapy with NAC-DCS can be a safe and effective regimen for locally advanced gastric cancer.

[A Case of Advanced Gastric Cancer Responding to Neoadjuvant Docetaxel/CDDP/S-1 Therapy with Metallic Stent Placement, Leading to Curative Surgery]

A 59-year-old man presented with epigastralgia. A diagnosis of advanced gastric cancer MLU, Circ, Type 3, 160 mm, tub2, cT4b (SI: panc), cN1, cM0, cH0, cP0, cCY0, cStage ⅢB was made. Because of difficulty with oral intake due to malignant outlet obstruction and tumor bleeding, endoscopic self-expanding metallic stent placement was performed. We administered chemotherapy involving docetaxel, cisplatin, and S-1(DCS). After 2 courses of chemotherapy, the primary lesion and regional lymph nodes had reduced in size. His response was judged as SD according to the RECIST criteria. The patient elected to undergo explorative laparotomy for assessment of the gastric cancer. The intraoperative findings showed that there was no pancreatic invasion, peritoneal dissemination, or distal metastasis, so a total gastrectomy and D2 lymph node dissection was performed. The pathological findings showed that there were very few cancer cells in the primary lesion, and a lymph node metastasis was found. The final stage was gastric cancer MLU, Circ, Type 3, 100 mm, muc, ypT4a(SE), ypN3a (13/51), ypM0, ypH0, ypP0, ypCY0, ypStage ⅢC. The therapy evaluation was Grade 1b. In summary, we encountered a patient with gastric cancer in whom curative surgery was made possible by undergoing chemotherapy and metallic stent placement.

Signatures of tumour immunity distinguish Asian and non-Asian gastric adenocarcinomas

OBJECTIVE

Differences in gastric cancer (GC) clinical outcomes between patients in Asian and non-Asian countries has been historically attributed to variability in clinical management. However, recent international Phase III trials suggest that even with standardised treatments, GC outcomes differ by geography. Here, we investigated gene expression differences between Asian and non-Asian GCs, and if these molecular differences might influence clinical outcome.

DESIGN

We compared gene expression profiles of 1016 GCs from six Asian and three non-Asian GC cohorts, using a two-stage meta-analysis design and a novel biostatistical method (RUV-4) to adjust for technical variation between cohorts. We further validated our findings by computerised immunohistochemical analysis on two independent tissue microarray (TMA) cohorts from Asian and non-Asian localities (n=665).

RESULTS

Gene signatures differentially expressed between Asians and non-Asian GCs were related to immune function and inflammation. Non-Asian GCs were significantly enriched in signatures related to T-cell biology, including CTLA-4 signalling. Similarly, in the TMA cohorts, non-Asian GCs showed significantly higher expression of T-cell markers (CD3, CD45R0, CD8) and lower expression of the immunosuppressive T-regulatory cell marker FOXP3 compared to Asian GCs (p<0.05). Inflammatory cell markers CD66b and CD68 also exhibited significant cohort differences (p<0.05). Exploratory analyses revealed a significant relationship between tumour immunity factors, geographic locality-specific prognosis, and postchemotherapy outcomes.

CONCLUSIONS

Analyses of >1600 GCs suggest that Asian and non-Asian GCs exhibit distinct tumour immunity signatures related to T-cell function. These differences may influence geographical differences in clinical outcome, and the design of future trials particularly in immuno-oncology.

[Clinical Experience of Nutritional Support in Patients Treated with Chemoradiotherapy for Locally Advanced Esophageal Cancer]

BACKGROUND

We investigated the efficacy of nutritional support in patients treated with chemoradiotherapy (CRT) for locally advanced esophageal cancer (LAEC).

METHODS

Eleven patients treated with CRT for locally advanced esophageal squamous cell carcinoma were included. Oral intake energy expenditure (OIE) and total energy expenditure (TEE) of all patients were calculated. Oral nutrition supplementations (ONSs) were utilized as nutritional therapy for the patients with malnutrition (OIE/TEE<0.6). Enteral nutrition (EN) was used in the patients with tumor obstruction.

RESULT

Two patients (18.9%) received ONS and 2 other patients received EN. Seven patients were able to take enough energy in the meal. The mean energy charge was increased from 67.9%to 84.9%. Nine patients (81.8%) completed the treatment regimen. During the CRT period, the prognostic nutritional index (PNI) and C-reactive protein level (mg/dL) were not significantly different. The body mass index decreased to 0.39 kg/m2 (p=0.039) and the mean weight loss was 1.57%. The overall response rate was 81.8%.

CONCLUSION

The nutritional support in the patients treated with CRT for LAEC is effective for maintaining nutritional status. Moreover, the response rate is satisfactory.

[A Case of Resected Gastric Cancer Invading the Esophagus with Esophageal Recurrence That Responded to Weekly Docetaxel／Cisplatin Chemotherapy]

A 77-year-old man underwent total gastrectomy with D1+ lymph node dissection after being diagnosed with cT4aN2M0, cStage ⅢB gastric cancer. Peritoneal dissemination was detected in the bursa omentalis. The pathological diagnosis after surgery was pT4aN3b (21/41) M1 (P1). He was treated with 6 courses of S-1 chemotherapy. Two years after surgery, upper gastrointestinal endoscopy revealed the presence of a tumor in the mid-thoracic esophagus. It was diagnosed to as metastatic esophageal cancer and treated with combination chemotherapy consisting of docetaxel (25 mg/m2, days 1, 8, 15) and cisplatin (25 mg/m2, days 1, 8, 15) in a 28-day cycle. A clinically complete response was observed after 5 courses of chemotherapy. Currently, the patient is alive with no signs of recurrence 12 months after the initial recurrence.

HER2 expression in locally advanced gastric cancer with extensive lymph node (bulky N2 or paraaortic) metastasis (JCOG1005-A trial)

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) is likely overexpressed and/or amplified in locally advanced gastric cancer with extensive (bulky N2 or paraaortic) lymph node metastasis, and patients may benefit from treatment with anti-HER2 antibodies. This study evaluated the frequency of HER2 overexpression and amplification in The Japanese Gastric Cancer Association (JGCA)-N3 and JGCA-bulky N2 tumors and the correlation between HER2 status and survival.

METHODS

HER2 status was assessed using immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in tumor tissue samples from 89 patients with gastric adenocarcinoma enrolled in the phase II JCOG0001 and JCOG0405 trials. HER2 positivity was defined as IHC3+ or IHC2+ with confirmatory FISH results.

RESULTS

Of the 89 tumor samples, 24 (27 %) showed HER2 positivity, including 16 scored as IHC3+ and 8 as IHC2+ and FISH positive. Multivariate analysis showed that the HER2 positivity rate was significantly higher in evaluable differentiated tumors than in undifferentiated tumors [18/44 (40.9 %) vs. 5/42 (11.9 %)]. Although the apparent OS curve of HER2 positive was superior to that of HER2 negative patients, HER2 status was not a statistically significant prognostic factor in multivariate analysis.

CONCLUSION

The HER2 positivity rate was relatively high in patients with JGCA-bulky N2 and JGCA-N3 gastric adenocarcinoma, suggesting that HER2 evaluation is essential to select the therapeutic regimen for neoadjuvant chemotherapy for this group of patients.

Randomised phase III trial of second-line irinotecan plus cisplatin versus irinotecan alone in patients with advanced gastric cancer refractory to S-1 monotherapy: TRICS trial

AIM

The optimal second-line regimen for treating advanced gastric cancer (AGC) remains unclear. While irinotecan (CPT-11) plus cisplatin (CDDP) combination therapy and CPT-11 monotherapy have been explored in the second-line setting, the superiority of second-line platinum-based therapies for AGC patients initially treated with S-1 monotherapy has not yet been evaluated; therefore, we aimed to examine the survival benefit of CPT-11/CDDP combination over CPT-11 monotherapy.

METHODS

AGC patients showing progression after S-1 monotherapy for advanced cancer or recurrence within 6 months after completion of S-1 adjuvant therapy were randomly allocated to CPT-11/CDDP (CPT-11, 60 mg/m(2); CDDP, 30 mg/m(2), q2w) or CPT-11 (150 mg/m(2), q2w).

RESULTS

Sixty-eight advanced and 95 recurrent cases were evaluated. The median overall survivals were 13.9 (95% confidence interval [CI]: 10.8-17.6) and 12.7 (95% CI: 10.3-17.2) months for CPT-11/CDDP and CPT-11, respectively (hazard ratio: 0.834; 95% CI: 0.596-1.167, P = 0.288). No significant differences were observed in the secondary end-points, including progression-free survival (4.6 [95% CI: 3.4-5.9] versus 4.1 [95% CI: 3.3-4.9]months) and response rate (16.9% [95% CI: 8.8-28.3] versus 15.4% [95% CI: 7.6-26.5]). The incidences of grade 3-4 anaemia (16% versus 4%) and elevated serum lactate dehydrogenase levels (5% versus 0%) were higher for CPT-11/CDDP than for CPT-11. Exploratory subgroup analysis revealed that CPT-11/CDDP was significantly more effective for intestinal-type AGC, compared with CPT-11 (overall survival: 15.8 versus 14.0 months; P = 0.019).

CONCLUSION

No survival benefit was observed upon adding CDDP to CPT-11 after S-1 monotherapy failure.

Technical reproducibility of single-nucleotide and size-based DNA biomarker assessment using DNA extracted from formalin-fixed, paraffin-embedded tissues

DNA extracted from formalin-fixed, paraffin-embedded (FFPE) tissues has been used in the past to analyze genetic polymorphisms. We evaluated the technical reproducibility of different types of assays for gene polymorphisms using DNA extracted from FFPE material. By using the MassARRAY iPLEX system, we investigated polymorphisms in DPYD (rs1801159 and rs3918290), UMPS (rs1801019), ERCC1 (rs11615), ERCC1 (rs3212986), and ERCC2 (rs13181) in 56 FFPE DNA samples. By using PCR, followed by size-based gel electrophoresis, we also examined TYMS 5' untranslated region 2R/3R repeats and GSTT1 deletions in 50 FFPE DNA samples and 34 DNAs extracted from fresh-frozen tissues and cell lines. Each polymorphism was analyzed by two independent runs. We found that iPLEX biomarker assays measuring single-nucleotide polymorphisms provided consistent concordant results. However, by using FFPE DNA, size-based PCR biomarkers (GSTT1 and TYMS 5' untranslated region) were discrepant in 32.7% (16/49, with exact 95% CI, 19.9%-47.5%; exact binomial confidence limit test) and 4.2% (2/48, with exact 95% CI, 0.5%-14.3%) of cases, respectively, whereas no discrepancies were observed using intact genomic DNA. Our findings suggest that DNA from FFPE material can be used to reliably test single-nucleotide polymorphisms. However, results based on size-based PCR biomarkers, and particularly GSTT1 deletions, using FFPE DNA need to be interpreted with caution. Independent repeated assays should be performed on all cases to assess potential discrepancies.

Validity of response assessment criteria in neoadjuvant chemotherapy for gastric cancer (JCOG0507-A)

BACKGROUND

Neoadjuvant chemotherapy may improve outcomes in gastric cancer. Tumor responses can be evaluated with RECIST, Japanese Classification of Gastric Carcinoma (JCGC), and histological criteria. These approaches have not yet been compared.

METHODS

We analyzed two phase II trials of neoadjuvant chemotherapy using S-1 plus cisplatin. JCOG0210 included patients with linitis plastica and large ulcero-invasive tumors, whereas JCOG0405 comprised those with para-aortic or bulky lymph node metastases. Radiologic evaluations were conducted using RECIST in JCOG0405 and JCGC criteria in JCOG0210, because the latter included many patients without measurable lesions. A histological responder was defined as a patient in whom one third or more of the tumor was affected. The hazard ratios (HR) for death between responders and non-responders and response rate differences between short- and long-term survivors were estimated.

RESULTS

In JCOG0210 (n = 49), HR was 0.54 in JCGC responders (P = 0.059) and 0.40 in histological responders (P = 0.005). The difference in response rates between short- and long-term survivors using histological criteria (34 %, P = 0.023) was greater than that using JCGC criteria (24 %, P = 0.15). In JCOG0405 (n = 51), HR was 0.67 in RECIST responders (P = 0.35) and 0.39 in histological responders (P = 0.030). In short- and long-term survivors, respectively, RECIST response rates were 62  and 67 % (P = 0.77), whereas histological response rates were 33  and 63 % (P = 0.048).

CONCLUSIONS

Histological criteria showed higher response assessment validity than RECIST or JCGC criteria and yielded the best surrogate endpoint for overall survival.

A phase II trial of capecitabine plus cisplatin (XP) for patients with advanced gastric cancer who relapsed after S-1 adjuvant therapy, XP after TS-1 adjuvant failure (XParTS)

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Background: For gastric cancer, standard regimens including S-1 for adjuvant and first-line chemotherapy have been established in Japan, while for early relapse after adjuvant therapy there is no standard treatment. In our retrospective analysis, relapse-free interval of less than 6 months was associated with poor progression-free survival (PFS) and overall survival (OS). To evaluate the efficacy and safety of capecitabine plus cisplatin (XP) treatment, for patients with advanced gastric cancer who relapsed within 6 months after S-1 adjuvant therapy, we conducted a multicenter phase II trial in Japan (NCT Identifier: NCT01412294). Methods: Patients who had received adjuvant chemotherapy for gastric cancer including S-1 for more than 12 weeks, thereafter relapsed within 6 months, 20–74 years of age and HER2- negative, were assigned to receive capecitabine 1000 mg/m2 bid for 14 days plus cisplatin 80 mg/m2 (day 1) every 3-week. The primary endpoint was PFS and the secondary endpoints were OS, time to treatment failure, overall response rate (ORR) and safety. Planned sample size was 40 according to median PFS threshold of 2 months. Results: From June 2011 to April 2014, 40 patients were assigned. Median age was 64, 32 males (80%); adjuvant chemotherapy: regimen, S-1 monotherapy (n=34, 85%), and median number of course was 7.0 (3-18). In 40 patients median PFS was 20 weeks (95%CI, 17-24), which was longer than protocol-specified threshold of 2 months. Median OS was 77 weeks (95%CI, 34-NE), ORR was 8/40 (22% including 12 NE cases; 95%CI, 44-74). Most common grade ≥3 adverse events (AEs) were neutropenia (23%), anemia (18%), hypercreatinine (18%), fatigue (13%), diarrhea (7.5%), and anorexia (7.5%). Conclusions: XP was safe and effective for those patients with relatively poor prognosis after S-1 adjuvant failure. Since profile of S-1 and capecitabine was different, XP can be recommended rather than S-1 plus cisplatin, Japanese standard first- line regimen. Clinical trial information: NCT01412294.

A randomized phase II trial of capecitabine plus cisplatin (XP) versus S-1 plus cisplatin (SP) as a first-line treatment for advanced gastric cancer: XP ascertainment versus SP randomized PII trial (XParTS II)

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Background: Capecitabine plus cisplatin (XP) is a standard global regimen for first-line treatment of advanced gastric cancer, however its efficacy compared to S-1 plus cisplatin (SP), a standard treatment in Japan has not been reported. To evaluate the efficacy of XP treatment, we conducted a multicenter randomized phase II trial comparing XP with SP for patients with advanced gastric cancer (ClinicalTrials.gov Identifier NCT0140624). Methods: Patients with unresectable metastatic or recurrent gastric cancer, 20–74 years of age and HER2-negative, were assigned to receive either S-1 40 mg/m2 bid for 21 days plus cisplatin 60 mg/m2 (day 8) every 5-week cycle or capecitabine 1000 mg/m2 bid for 14 days plus cisplatin 80 mg/m2 (day 1) every 3-week cycle. The primary endpoint was progression-free survival (PFS). Secondary endpoints were overall survival (OS), time to treatment failure, overall response rate (ORR) and safety. Planned sample size was 100 (50 in each arm) according to PFS at 24-weeks. Immunohistochemical evaluation of biomarkers was also implemented. Results: From November 2011 to June 2013, 116 patients were randomized: median age, 65 years; 79 (68%) male; 63 intestinal and 53 diffuse cancer subtypes. In 109 eligible patients, 24-week %PFS was higher in both groups than the protocol-specified threshold of 40%. Median PFS for SP vs. XP was 25 weeks vs. 23 weeks (HR, 0.76; 95%CI, 0.5-1.16; p=0.203); OS was 58 weeks vs. 56 weeks (HR, 0.90; 95%CI, 0.52-1.57; p=0.712); and ORR was 27.5% vs. 32.7% (p=0.562), respectively. Sub-group analysis by histological classification showed that SP gave better PFS than XP in the diffuse type (HR, 0.42; 95%CI, 0.20-0.86; p=0.015) with no other statistical difference. Most common grade ≥3 adverse events with SP and XP were anemia (16%/ 19%), neutropenia (9%/17%), anorexia (18%/13%), diarrhea (11%/0%), nausea or vomiting (11%/15%), fatigue (5%/6%) and hyponatremia (7%/13%), respectively. Conclusions: XP and SP are comparable and can be recommended as 1st line treatments for advanced gastric cancer. Further analysis for biomarkers related to histology is warranted. Clinical trial information: NCT0140624.

A randomized 2X2 phase II trial comparing two and four courses of S-1/cisplatin (SC) and paclitaxel/cisplatin (PC) as neoadjuvant chemotherapy for locally resectable advanced gastric cancer: Survival results of COMPASS

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Background: The prognosis for stage III gastric cancer is not satisfactory even by S-1 adjuvant chemotherapy. Neoadjuvant chemotherapy is a promising approach but its optimal duration and regimen have not been established yet. Methods: We conducted a randomized phase II trial to compare two or four courses and regimen of SC or PC using a two-by-two factorial design.Key eligibility criteria was (i) T2-3/N+ or T4aN0 in case of schirrhous or junctional tumors, T2-3 with N+ to the major branched artery, T4aN+, T4b, para-aortic nodal metastases, or resectable minimal peritoneal metastases confirmed by laparoscopy and (ii) no other distant metastasis. Patients received S-1 (80 mg/m2 for 21 days with 1 week rest) / cisplatin (60 mg/m2 at day 8) or paclitaxel / cisplatin (80 mg/m2 and 25 mg/m2, respectively, on days 1, 8, and 15 with 1 week rest) as neoadjuvant chemotherapy. Then, patients received D2 gastrectomy with curative intent. The primary endpoint was 3-year overall survival. The planned sample size was 80 eligible patients in total so that the treatment group with the superior observed 3-year OS rate by 10% increase was to be selected with a probability of 88% or higher. Results: Eighty-three patients were assigned to SC (n=41, two courses in 21 and four courses in 20) and PC (n=42, two courses in 21 and four courses in 21). Pathological response rate was 42% (17/41) in SC and 33% (14/42) in PC, and 36% (15/42) in the two courses and 39% (16/41) in the four courses. Pathological CR was 0% (0/42) in the two courses and 10% (4/41) in the four courses. Grade 3/4 adverse events by chemotherapy and grade 3/4 surgical morbidities defined by Clavien-Dindo classification were both less than 10% in each arm without treatment-related death. The 3-year OS was 60.9% (95% CI, 44.3-73.9%) in SC and 64.3% (95% CI, 47.9-76.7%) in PC, and 64.3% (95% CI, 47.9-76.7%) in the two courses and 61.0% (95% CI, 44.4-74.0%) in the four courses. Conclusions: Two courses of SC as neoadjuvant chemotherapy is recommended for a test arm of future phase III study for patients with locally resectable advanced gastric cancer. Clinical trial information: UMIN000002595.

Feasibility of enhanced recovery after surgery in gastric surgery: a retrospective study

BACKGROUND

Enhanced recovery after surgery (ERAS) programs have been reported to be feasible and useful for maintaining physiological function and facilitating recovery after colorectal surgery. The feasibility of such programs in gastric surgery remains unclear. This study assessed whether an ERAS program is feasible in patients who undergo gastric surgery.

METHODS

The subjects were patients who underwent gastric surgery between June 2009 and February 2011 at the Department of Gastrointestinal Surgery, Kanagawa Cancer Center. They received perioperative care according to an ERAS program. All data were retrieved retrospectively. The primary end point was the incidence of postoperative complications. The secondary end point was postoperative outcomes.

RESULTS

A total of 203 patients were studied. According to the Clavien-Dindo classification, the incidence of ≥ grade 2 postoperative complications was 10.8% and that of ≥ grade 3 complications was 3.9%. Nearly all patients did not require delay of meal step-up (95.1%). Only 6 patients (3.0%) underwent reoperation. The median postoperative hospital stay was 9 days. Only 4 patients (2.0%) required readmission. There was no mortality.

CONCLUSIONS

Our results suggest that our ERAS program is feasible in patients who undergo gastric surgery.

Double-blind, placebo-controlled, randomized phase II study of TJ-14 (hangeshashinto) for gastric cancer chemotherapy-induced oral mucositis

BACKGROUND

Hangeshashinto (TJ-14, a Kampo medicine), which reduces the level of prostaglandin E2 and affects the cyclooxygenase activity, alleviates chemotherapy-induced oral mucositis (COM). We conducted a randomized comparative trial to investigate whether TJ-14 prevents and controls COM in patients with gastric cancer.

METHODS

We randomly assigned patients with gastric cancer who developed moderate-to-severe oral mucositis (CTCAE v4.0 grade ≧1) during any cycle of chemotherapy to receive either TJ-14 or a placebo as a double-blind trial. The patients received a placebo or TJ-14 for 2-6 weeks according to the chemotherapy regimen from the beginning of the next course of chemotherapy. The primary end point was the incidence of grade ≧2 oral mucositis in the protocol treatment course, and the secondary end points were the time to disappearance of oral mucositis and the incidence of adverse events.

RESULTS

Following the key opening of the blinding protocol, we analyzed 91 eligible patients (TJ-14: 45, placebo: 46) using a "per protocol set" analysis. The incidence of ≧grade 2 COM was 40.0 % in the TJ-14 group and 41.3 % in the placebo group (p = 0.588). The median duration of ≧grade 2 COM was 14 days in the TJ-14 group and 16 days in the placebo group (p = 0.894). Meanwhile, the median duration of any grade of COM was 9 days in the TJ-14 group and 17 days in the placebo group among the patients who developed grade 1 symptoms during the screening cycle [hazard ratio 0.60; 95 % CI (0.23-1.59), p = 0.290].

CONCLUSIONS

Although TJ-14 treatment did not reduce the incidence of ≥2 COM in the patients who developed mucositis during chemotherapy for gastric cancer, a trend was observed in which TJ-14 reduced the risk of COM in the patients who developed grade 1 COM during the screening cycle. Further, phase III studies with a larger sample size are needed to clarify the protective effects of TJ-14 for COM.

Low creatinine clearance is a risk factor for D2 gastrectomy after neoadjuvant chemotherapy

BACKGROUND

The feasibility and safety of D2 surgery following neoadjuvant chemotherapy (NAC) has not been fully evaluated in patients with gastric cancer. Moreover, risk factor for surgical complications after D2 gastrectomy following NAC is also unknown. The purpose of the present study was to identify risk factors of postoperative complications after D2 surgery following NAC.

METHODS

This study was conducted as an exploratory analysis of a prospective, randomized Phase II trial of NAC. The surgical complications were assessed and classified according to the Clavien-Dindo classification. A uni- and multivariate logistic regression analyses were performed to identify risk factors for morbidity.

RESULTS

Among 83 patients who were registered to the Phase II trial, 69 patients received the NAC and D2 gastrectomy. Postoperative complications were identified in 18 patients and the overall morbidity rate was 26.1 %. The results of univariate and multivariate analyses of various factors for overall operative morbidity, creatinine clearance (CCr) ≤ 60 ml/min (P = 0.016) was identified as sole significant independent risk factor for overall morbidity. Occurrence of pancreatic fistula was significantly higher in the patients with a low CCr than in those with a high CCr.

CONCLUSIONS

Low CCr was a significant risk factor for surgical complications in D2 gastrectomy after NAC. Careful attention is required for these patients.

High false-negative proportion of intraoperative histological examination as a serious problem for clinical application of sentinel node biopsy for early gastric cancer: final results of the Japan Clinical Oncology Group multicenter trial JCOG0302

BACKGROUND

To evaluate the feasibility and accuracy of diagnosis using sentinel node (SN) biopsy in T1 gastric cancer, a multicenter trial was conducted by the Japan Clinical Oncology Group (JCOG).

METHODS

Sentinel node biopsy with indocyanine green (ICG) was performed in patients with T1 gastric cancer. Green-stained nodes (GNs), representing SNs, were removed first, and gastrectomy with lymphadenectomy was then performed. GNs in one plane (with the largest dimension) were histologically examined intraoperatively by frozen section with hematoxylin and eosin (H&E) stain. All harvested lymph nodes (GNs and non-GNs) were histologically examined by paraffin section after surgery. The primary endpoint was to determine the proportion of false negatives, which was defined as the number of patients with negative GNs by frozen section divided by those with positive GNs and/or positive non-GNs by paraffin section. The sample size was set at 1,550, based on the expected and threshold value as 5 and 10 % in the proportion of false negatives.

RESULTS

Accrual was suspended when 440 patients were enrolled because the proportion of false negatives was high. In the primary analysis, the proportion of false negatives was 46 % (13/28) after a learning period with 5 patients for each institution. Seven of 13 patients had nodal metastases outside the lymphatic basin. False negatives remained at 14 % (4/28) even by examining additional sections of GNs by paraffin section.

CONCLUSIONS

The proportion of false negatives was much higher than expected. Intraoperative histological examination using only one plane is not an appropriate method for clinical application of SN biopsy in gastric cancer surgery.

Neoadjuvant chemotherapy with S-1 and cisplatin followed by D2 gastrectomy with para-aortic lymph node dissection for gastric cancer with extensive lymph node metastasis

BACKGROUND

Locally advanced gastric cancer with extensive regional and/or para-aortic lymph node (PAN) metastases is typically unresectable and associated with poor outcomes. This study investigated the safety and efficacy of S-1 plus cisplatin followed by extended surgery with PAN dissection for gastric cancer with extensive lymph node metastasis.

METHODS

Patients with gastric cancer with bulky lymph node metastasis along the coeliac artery and its branches and/or PAN metastasis received two or three 28-day cycles of S-1 plus cisplatin, followed by gastrectomy with D2 plus PAN dissection. The primary endpoint was the percentage of complete resections with clear margins in the primary tumour (R0 resection). A target sample size of 50 with one-sided α of 0.105 and β of approximately 0.2 corresponded to an expected R0 rate of 65 per cent and a threshold of 50 per cent.

RESULTS

Between February 2005 and June 2007, 53 patients were enrolled, of whom 51 were eligible. The R0 resection rate was 82 per cent. Clinical and pathological response rates were 65 and 51 per cent respectively. The 3- and 5-year overall survival rates were 59 and 53 per cent respectively. During chemotherapy, grade 3/4 neutropenia occurred in 19 per cent and grade 3/4 non-haematological adverse events in 15.4 per cent. The incidence of grade 3/4 adverse events related to surgery was 12 per cent. There were no reoperations or treatment-related deaths.

CONCLUSION

For locally advanced gastric cancer with extensive lymph node metastasis, 4-weekly S-1 plus cisplatin followed by surgery including PAN dissection was safe and effective for some patients. Further investigation of this treatment strategy is warranted.