Prognostic Impact of Post-operative Infectious Complications in Gastric Cancer Patients Receiving Neoadjuvant Chemotherapy: Post Hoc Analysis of a Randomized Controlled Trial, JCOG0501

PURPOSE

Post-operative infectious complication (IC) is a well-known negative prognostic factor, while showing neoadjuvant chemotherapy (NAC) may cancel out the negative influence of IC. This analysis compared the clinical impacts of IC according to the presence or absence of NAC in gastric cancer patients enrolled in the phase III clinical trial (JCOG0501) which compared upfront surgery (arm A) and NAC followed by surgery (arm B) in type 4 and large type 3 gastric cancer.

METHODS

The subjects were 224 patients who underwent R0 resection out of 316 patients enrolled in JCOG0501. The prognoses of the patients with or without ICs in each arm were investigated by univariable and multivariable Cox regression analyses.

RESULTS

There were 21 (20.0%) IC occurrences in arm A and 15 (12.6%) in arm B. In arm A, the overall survival (OS) of patients with ICs was slightly worse than those without IC (3-year OS, 57.1% in patients with ICs, 79.8% in those without ICs; adjusted hazard ratio (95% confidence interval), 1.292 (0.655-2.546)). In arm B, patients with ICs showed a trend of better survival than those without ICs (3-year OS, 80.0% in patients with IC, 74.0% in those without IC; adjusted hazard ratio, 0.573 (0.226-1.456)).

CONCLUSION

This study could not indicate the negative prognostic influence of ICs in gastric cancer patients receiving NAC, which might be canceled by NAC. To build exact evidence, further investigation with prospective and large numbers of data might be expected.

Key nodal stations for predicting splenic hilar nodal metastasis in upper advanced gastric cancer without invasion of the greater curvature

Background

Standard surgery for upper advanced gastric cancer without invasion of the greater curvature (UGC-GC) is spleen-preserving D2 total gastrectomy without dissection of the splenic-hilar nodes (#10). However, some patients with nodal metastasis to #10 survive more than 5 years due to nodal dissection of #10. If nodal metastasis to #10 is predictable based on the positivity of other nodes dissected by the current standard surgery without #10 nodal dissection, physicians may be able to consider #10 dissection.

Methods

This study retrospectively reviewed data from the National Cancer Center Hospital in Japan between 2000 and 2012. We selected cases that met the following criteria: (1) D2 or more total gastrectomy with splenectomy, (2) UGC-GC, and (3) histological type is gastric adenocarcinoma. We performed univariate and multivariate analyses concerning lymph node stations associated with #10 metastasis.

Results

A total of 366 patients were examined. A multivariate analysis revealed that #10 metastasis was associated with positivity of the nodes along the short gastric arteries (#4sa) and distal nodes along the splenic artery (#11d) (#4sa: p = 0.003, #11d: p = 0.016). When either key node was positive, the metastatic rate of #10 was 24.4%, and the therapeutic value index was 13.3.

Conclusions

#4sa and #11d were key lymph nodes predicting #10 nodal metastasis in UGC-GC. When these key nodes are positive on computed tomography before surgery or according to a rapid pathological examination during surgery, dissection of #10 should be considered even if upper advanced tumors are not invading the greater curvature.

Early endpoints of a randomized phase II trial of preoperative chemotherapy with S-1/CDDP with or without trastuzumab followed by surgery for HER2-positive resectable gastric or esophagogastric junction adenocarcinoma with extensive lymph node metastasis: Japan Clinical Oncology Group study JCOG1301C (Trigger Study)

BACKGROUND

This randomized phase II study explored the superiority of trastuzumab plus S-1 plus cisplatin (SP) over SP alone as neoadjuvant chemotherapy (NAC) for HER2-positive resectable gastric cancer with extensive lymph node metastasis.

METHODS

Eligible patients with HER2-positive gastric or esophagogastric junction cancer and extensive lymph node metastasis were randomized to receive three or four courses of preoperative chemotherapy with SP (arm A) or SP plus trastuzumab (arm B). Following gastrectomy, adjuvant chemotherapy with S-1 was administered for 1 year in both arms. The primary endpoint was overall survival, and the sample size was 130 patients in total. The trial is registered with the Japan Registry of Clinical Trials, jRCTs031180006.

RESULTS

This report elucidates the early endpoints, including pathological findings and safety. The study was terminated early due to slow patient accruals. In total, 46 patients were allocated to arm A (n = 22) and arm B (n = 24). NAC was completed in 20 patients (91%) in arm A and 23 patients (96%) in arm B, with similar incidences of grade 3-4 hematological and non-hematological adverse events. Objective response rates were 50% in arm A and 84% in arm B (p = 0·065). %R0 resection rates were 91% and 92%, and pathological response rates (≥ grade 1b in Japanese classification) were 23% and 50% (p = 0·072) in resected patients, respectively.

CONCLUSIONS

Trastuzumab can be safely added to platinum-containing doublet chemotherapy as NAC, and it has the potential to contribute to higher antitumor activity against locally advanced, HER2-positive gastric or esophagogastric junction cancer with extensive nodal metastasis.

Adjuvant and post-recurrent treatment patterns in patients with resectable gastric cancer in japan: a retrospective database cohort study

BACKGROUND

This study examined temporal shifts in adjuvant therapy patterns in Japanese patients with resectable gastric cancer (GC) and treatment patterns of first-line and subsequent therapy among those with recurrent disease.

METHODS

This retrospective analysis of hospital-based administrative claims data (April 1, 2008 to March 31, 2022) included adults (aged ≥ 20 years) with GC who started adjuvant therapy on or after October 1, 2008 (adjuvant cohort) and patients in the adjuvant cohort with disease recurrence (recurrent cohort), further defined by the time to recurrence (≤ 180 or > 180 days after adjuvant therapy).

RESULTS

In the adjuvant cohort (n = 17,062), the most common regimen during October 2008-May 2016 was tegafur/gimeracil/oteracil potassium (S-1; 95.7%). As new standard adjuvant regimen options were established, adjuvant S-1 use decreased to 65.0% and fluoropyrimidine plus oxaliplatin or docetaxel plus S-1 use increased to 15.0% and 20.0%, respectively, in September 2019-March 2022. In the recurrent cohort with no history of trastuzumab/trastuzumab deruxtecan treatment (n = 1257), the most common first-line regimens were paclitaxel plus ramucirumab (34.0%), capecitabine plus oxaliplatin (CapeOX; 17.0%), and nab-paclitaxel plus ramucirumab (10.1%) in patients with early recurrence, and S-1 plus oxaliplatin (26.3%), S-1 plus cisplatin (15.3%), CapeOX (14.0%), S-1 (13.2%), and paclitaxel plus ramucirumab (10.8%) in those with late recurrence.

CONCLUSIONS

This study demonstrated temporal shifts in adjuvant treatment patterns that followed the establishment of novel regimens, and confirmed that post-recurrent treatment patterns were consistent with the Japanese Gastric Cancer Association guideline recommendations.

Impact of D2 Total Gastrectomy Including Splenectomy for Scirrhous Gastric Cancer in the Era of Effective Adjuvant Chemotherapy

BACKGROUND

Total gastrectomy with D2 dissection including splenectomy (TGS) is usually selected for locally resectable scirrhous gastric cancer (SGC), which was established in the era of surgery alone. However, it remains unclear whether TGS for SGC is justified in the era of effective adjuvant chemotherapy.

METHODS

This study included 112 SGC patients, consisting of 60 cases treated between January 2000 and December 2006 (Former group), and 52 cases treated between January 2007 and December 2016 (Latter group). We collected clinicopathological data and then examined the survival and the therapeutic value indexes.

RESULTS

The background characteristics were well-balanced, except for sex and physical status. The Latter group might be characterized by frequent female (P = 0.037) and poorer physical status (P = 0.048). Adjuvant chemotherapy was administered to 86.5% of the Latter group and was 11.7% of the Former group (P < 0.001). The 5-year-overall survival rate of the Latter group was 58.7% (95% confidence interval: 43.5-71.1), seems better than that of the Former group (44.5%; 95% confidence interval 31.7-56.6) (hazard ratio = 0.758, P = 0.291). Improvement of the index from the Former group was observed in the Latter group at almost all stations. The ratio of the index between two groups was 1.42 at the D1 station and 1.67 at the D2 station. Index of splenic hilar node ranked similarly high in both groups.

CONCLUSION

The therapeutic value index was improved in almost all nodal stations by S-1 adjuvant chemotherapy, especially in D2 nodes. TGS would be more important for locally resectable SGC in the era of effective adjuvant chemotherapy.

Short-term outcomes of preoperative chemotherapy with docetaxel, oxaliplatin, and S-1 for gastric cancer with extensive lymph node metastasis (JCOG1704)

BACKGROUND

The prognosis for marginally resectable gastric cancer with extensive lymph node metastasis (ELM) remains unfavorable, even after R0 resection. To assess the safety and efficacy of preoperative docetaxel, oxaliplatin, and S-1 (DOS), we conducted a multicenter phase II trial.

METHODS

Eligibility criteria included histologically proven HER2-negative gastric adenocarcinoma with bulky nodal (bulky N) involvement around major branched arteries or para-aortic node (PAN) metastases. Patients received three cycles of docetaxel (40 mg/m2, day 1), oxaliplatin (100 mg/m2, day 1), and S-1 (80-120 mg/body, days 1-14), followed by gastrectomy with D2 plus PAN dissection. Subsequently, patients underwent postoperative chemotherapy with S-1 for 1 year. The primary endpoint was major (grade ≥ 2a) pathological response rate (pRR) according to the Japanese Classification of Gastric Carcinoma criteria.

RESULTS

Between October 2018 and March 2022, 47 patients (bulky N, 20; PAN, 17; both, 10) were enrolled in the trial. One patient was ineligible. Another declined any protocol treatments before initiation. Among the 45 eligible patients who initiated DOS chemotherapy, 44 (98%) completed 3 cycles and 42 (93%) underwent R0 resection. Major pRR and pathological complete response rates among the 46 eligible patients, including the patient who declined treatment, were 57% (26/46) and 24% (11/46), respectively. Common grade 3 or 4 toxicities were neutropenia (24%), anorexia (16%), febrile neutropenia (9%), and diarrhea (9%). No treatment-related deaths occurred.

CONCLUSIONS

Preoperative chemotherapy with DOS yielded favorable pathological responses with an acceptable toxicity profile. This multimodal approach is highly promising for treating gastric cancer with ELM.

Risk factors for abdominal surgical infectious complications after distal gastrectomy for gastric cancer: A post-hoc analysis of a randomized controlled trial (JCOG0912)

BACKGROUND

Abdominal surgical infectious complications (ASIC) after gastrectomy for gastric cancer impair patients' survival and quality of life. JCOG0912 was conducted to compare laparoscopy-assisted distal gastrectomy with open distal gastrectomy for clinical stage IA or IB gastric cancer. The present study aimed to identify risk factors for ASIC using prospectively collected data.

METHODS

We performed a post-hoc analysis of the risk factors for ASIC using the dataset from JCOG0912. All complications were evaluated according to the Clavien-Dindo classification (CD). ASIC was defined as CD grade I or higher anastomotic leakage, pancreatic fistula, abdominal abscess, and wound infection. Analyses were performed using the logistic regression model for univariable and multivariable analyses.

RESULTS

A total of 910 patients were included (median age, 63 years; male sex, 61 %). Among them, ASIC occurred in 5.8 % of patients. In the univariable analysis, male sex (odds ratio [OR] 2.855, P = 0.003), diabetes (OR 2.565, P = 0.029), and Roux-en-Y (R-Y) reconstruction (vs. Billroth Ⅰ, OR 2.707, P = 0.002) were significant risk factors for ASIC. In the multivariable analysis, male sex (OR 2.364, P = 0.028) and R-Y reconstruction (vs. Billroth Ⅰ, OR 2.310, P = 0.015) were independent risk factors for ASIC.

CONCLUSIONS

Male sex and R-Y reconstruction were risk factors for ASIC after distal gastrectomy. Therefore, when performing surgery on male patients or when R-Y reconstruction is selected after gastrectomy for gastric cancer, surgeons should pay special attention to prevent ASIC.

Protocol digest of a randomized controlled adaptive Phase II/III trial of neoadjuvant chemotherapy for Japanese patients with oesophagogastric junction adenocarcinoma: Japan Clinical Oncology Group Study JCOG2203 (NEO-JPEG)

Treatment strategies for oesophagogastric junction adenocarcinoma have not been standardized despite its poor prognosis due to differences in the incidence rates between Western countries and Asia. This randomized Phase II/III trial was initiated in June 2023 to determine which neoadjuvant chemotherapy regimen, docetaxel, oxaliplatin and S-1 or fluorouracil, oxaliplatin and docetaxel, is a more promising treatment in Phase II and confirm the superiority of neoadjuvant chemotherapy with docetaxel, oxaliplatin and S-1 or fluorouracil, oxaliplatin and docetaxel followed by surgery and postoperative chemotherapy over upfront surgery and postoperative chemotherapy in terms of overall survival in patients with Clinical Stage III or IVA oesophagogastric junction adenocarcinoma in Phase III. A total of 460 patients, including 150 patients in Phase II and 310 patients in Phase III, are planned to be enrolled from 85 hospitals in Japan over 5 years. This trial has been registered in the Japan Registry of Clinical Trials as jRCTs031230182 (https://jrct.niph.go.jp/latest-detail/jRCTs031230182).

Neoadjuvant and adjuvant pembrolizumab plus chemotherapy in locally advanced gastric or gastro-oesophageal cancer (KEYNOTE-585): an interim analysis of the multicentre, double-blind, randomised phase 3 study

BACKGROUND

The benefit of combination neoadjuvant and adjuvant chemotherapy and immune checkpoint inhibition in patients with locally advanced, resectable gastric or gastro-oesophageal adenocarcinoma is unknown. We assess the antitumor activity of neoadjuvant and adjuvant pembrolizumab plus chemotherapy in patients with locally advanced resectable gastric or gastro-oesophageal adenocarcinoma.

METHODS

The KEYNOTE-585 study is a multicentre, randomised, placebo-controlled, double-blind, phase 3 study done at 143 medical centres in 24 countries. Eligible patients were aged 18 years or older with untreated, locally advanced, resectable gastric or gastro-oesophageal adenocarcinoma, and an Eastern Cooperative Oncology Group performance status 0-1. Patients were randomly assigned (1:1) by an interactive voice response system and integrated web response system to neoadjuvant pembrolizumab 200 mg intravenously or placebo (saline) plus cisplatin-based doublet chemotherapy (main cohort) every 3 weeks for 3 cycles, followed by surgery, adjuvant pembrolizumab or placebo plus chemotherapy for 3 cycles, then adjuvant pembrolizumab or placebo for 11 cycles. A small cohort was also randomly assigned (1:1) to pembrolizumab or placebo plus fluorouracil, docetaxel, and oxaliplatin (FLOT)-based chemotherapy (FLOT cohort) every 2 weeks for four cycles, followed by surgery, adjuvant pembrolizumab, or placebo plus FLOT for four cycles, then adjuvant pembrolizumab or placebo for 11 cycles. Patients were stratified by geographic region, tumour stage, and chemotherapy backbone. Primary endpoints were pathological complete response (reviewed centrally), event-free survival (reviewed by the investigator), and overall survival in the intention-to-treat population, and safety assessed in all patients who received at least one dose of study treatment. The study is registered at ClinicalTrials.gov, NCT03221426, and is closed to accrual.

FINDINGS

Between Oct 9, 2017, and Jan 25, 2021, of 1254 patients screened, 804 were randomly assigned to the main cohort, of whom 402 were assigned to the pembrolizumab plus cisplatin-based chemotherapy group and 402 to the placebo plus cisplatin-based chemotherapy group, and 203 to the FLOT cohort, of whom 100 were assigned to the pembrolizumab plus FLOT group and 103 to placebo plus FLOT group. In the main cohort of 804 participants, 575 (72%) were male and 229 (28%) were female. In the main cohort, after median follow-up of 47·7 months (IQR 38·0-54·8), pembrolizumab was superior to placebo for pathological complete response (52 [12·9%; 95% CI 9·8-16·6] of 402 vs eight [2·0%; 0·9-3·9] of 402; difference 10·9%, 95% CI 7·5 to 14·8; p<0·00001). Median event-free survival was longer with pembrolizumab versus placebo (44·4 months, 95% CI 33·0 to not reached vs 25·3 months, 20·6 to 33·9; hazard ratio [HR] 0·81, 95% CI 0·67 to 0·99; p=0·0198) but did not meet the threshold for statistical significance (p=0·0178). Median overall survival was 60·7 months (95% CI 51·5 to not reached) in the pembrolizumab group versus 58·0 months (41·5 to not reached) in the placebo group (HR 0·90, 95% CI 0·73 to 1·12; p=0·174). Grade 3 or worse adverse events of any cause occurred in 312 (78%) of 399 patients in the pembrolizumab group and 297 (74%) of 400 patients in the placebo group; the most common were nausea (240 [60%] vs 247 [62%]), anaemia (168 [42%] vs 158 [40%]), and decreased appetite (163 [41%] vs 172 [43%]). Treatment-related serious adverse events were reported in 102 (26%) and 97 (24%) patients. Treatment-related adverse events that led to death occurred in four (1%) patients in the pembrolizumab group (interstitial ischaemia, pneumonia, decreased appetite, and acute kidney injury [n=1 each]) and two (<1%) patients in the placebo group (neutropenic sepsis and neutropenic colitis [n=1 each]).

INTERPRETATION

Although neoadjuvant and adjuvant pembrolizumab versus placebo improved the pathological complete response, it did not translate to significant improvement in event-free survival in patients with untreated, locally advanced resectable gastric or gastro-oesophageal cancer.

FUNDING

Merck Sharp & Dohme.

Precancerous nature of intestinal metaplasia with increased chance of conversion and accelerated DNA methylation

OBJECTIVE

The presence of intestinal metaplasia (IM) is a risk factor for gastric cancer. However, it is still controversial whether IM itself is precancerous or paracancerous. Here, we aimed to explore the precancerous nature of IM by analysing epigenetic alterations.

DESIGN

Genome-wide DNA methylation analysis was conducted by EPIC BeadArray using IM crypts isolated by Alcian blue staining. Chromatin immunoprecipitation sequencing for H3K27ac and single-cell assay for transposase-accessible chromatin by sequencing were conducted using IM mucosa. NOS2 was induced using Tet-on gene expression system in normal cells.

RESULTS

IM crypts had a methylation profile unique from non-IM crypts, showing extensive DNA hypermethylation in promoter CpG islands, including those of tumour-suppressor genes. Also, the IM-specific methylation profile, namely epigenetic footprint, was present in a fraction of gastric cancers with a higher frequency than expected, and suggested to be associated with good overall survival. IM organoids had remarkably high NOS2 expression, and NOS2 induction in normal cells led to accelerated induction of aberrant DNA methylation, namely epigenetic instability, by increasing DNA methyltransferase activity. IM mucosa showed dynamic enhancer reprogramming, including the regions involved in higher NOS2 expression. NOS2 had open chromatin in IM cells but not in gastric cells, and IM cells had frequent closed chromatin of tumour-suppressor genes, indicating their methylation-silencing. NOS2 expression in IM-derived organoids was upregulated by interleukin-17A, a cytokine secreted by extracellular bacterial infection.

CONCLUSIONS

IM cells were considered to have a precancerous nature potentially with an increased chance of converting into cancer cells, and an accelerated DNA methylation induction due to abnormal NOS2 expression.

5-year follow-up results of a JCOG1104 (OPAS-1) phase III non-inferiority trial to compare 4 courses and 8 courses of S-1 adjuvant chemotherapy for pathological stage II gastric cancer

BACKGROUND

Postoperative adjuvant chemotherapy with S-1 for 1 year (corresponding to eight courses) is the standard treatment for pathological stage II gastric cancer. The phase III trial (JCOG1104) investigating the non-inferiority of four courses of S-1 to eight courses was terminated due to futility at the first interim analysis. To confirm the primary results, we reported the results after a 5-years follow-up in JCOG1104.

METHODS

Patients histologically diagnosed with stage II gastric cancer after radical gastrectomy were randomly assigned to receive S-1 for eight or four courses. In detail, 80 mg/m2/day S-1 was administered for 4 weeks followed by a 2-week rest as a single course.

RESULTS

Between February 16, 2012, and March 19, 2017, 590 patients were enrolled and randomly assigned to 8-course (295 patients) and 4-course (295 patients) regimens. After a 5-years follow-up, the relapse-free survival at 3 years was 92.2% for the 8-course arm and 90.1% for the 4-course arm, and that at 5 years was 87.7% for the 8-course arm and 85.6% for the 4-course arm (hazard ratio 1.265, 95% CI 0.846-1.892). The overall survival at 3 years was 94.9% for the 8-course arm, 93.2% for the 4-course arm, and that at 5 years was 89.7% for the 8-course arm, and 88.6% for the 4-course arm (HR 1.121, 95% CI 0.719-1.749).

CONCLUSIONS

The survival of the four-course arm was slightly but consistently inferior to that of the eight-course arm. Eight-course S-1 should thus remain the standard adjuvant chemotherapy for pathological stage II gastric cancer.

Clinical impact of skeletal muscle mass change during the neoadjuvant chemotherapy period in patients with gastric cancer: An ancillary study of JCOG1002

BACKGROUND

Recent studies have revealed that sarcopenia is associated with postoperative complications and poor prognosis. Although neoadjuvant chemotherapy is a promising treatment for gastric cancer, its toxicity may lead to the loss of skeletal muscle mass. This study investigates the changes in skeletal muscle mass during neoadjuvant chemotherapy and its clinical impact on patients with locally advanced gastric cancer.

METHODS

Fifty patients who completed two courses of neoadjuvant chemotherapy followed by surgery were included. Skeletal muscle mass was measured using computed tomography images before and after chemotherapy. The proportion of skeletal muscle mass change (%SMC) during neoadjuvant chemotherapy and its cutoff value was explored using the receiver operating characteristic for the overall survival of patients undergoing R0 resection. Risk factors of skeletal muscle mass loss were also evaluated.

RESULTS

Overall, 64% of patients had skeletal muscle mass loss during neoadjuvant chemotherapy (median %SMC -3.4%; range: -18.9% to 10.3%). Multivariable analysis identified older age (≥70 years) as an independent predictor of skeletal muscle mass loss (mean [95% confidence interval]: -4.70% [-8.83 to -0.58], p = 0.026). Among 43 patients undergoing R0 resection, %SMC <-6.9% was an independent poor prognostic factor for overall survival (hazard ratio, 11.53; 95% confidence interval, 2.78-47.80) and relapse-free survival (hazard ratio 4.54, 95% confidence interval 1.50-13.81).

CONCLUSIONS

Skeletal muscle mass loss occurs frequently during neoadjuvant chemotherapy for locally advanced gastric cancer and could adversely affect survival outcomes.

Association between the antiadhesion membrane and small bowel obstruction after open gastrectomy: A supplemental analysis of the randomized controlled JCOG1001 trial

Aim

Postoperative small bowel obstruction (SBO) is one of the major complications that is mainly caused by postoperative adhesion. Recently, the antiadhesion membrane has become popular for postoperative SBO prevention. However, its efficacy is yet to be confirmed in the gastric cancer surgery field. Here, we conducted the supplemental analysis of the randomized controlled trial JCOG1001 to investigate the efficacy of the antiadhesion membrane on SBO prevention in patients with open gastrectomy for gastric cancer.

Methods

Of the 1204 patients enrolled in JCOG1001, 1200 patients were included. The development of SBO of Grade ≥ IIIa according to the Clavien-Dindo classification was recorded. Univariable and multivariable analyses were performed using the Fine and Gray model to determine the risk factors for SBO.

Results

Fifty-one patients developed SBO (median follow-up duration: 5.6 years). Total gastrectomy, combined resection, and blood loss significantly increased the risk for SBO development in the univariable analysis. Large amount of blood loss was independently associated with SBO development in the multivariable analysis (hazard ratio [HR], 3.089; 95% confidence interval [CI], 1.562-6.109, p = 0.0012). Antiadhesion membrane did not reduce the risk for SBO (HR, 1.299; 95% CI 0.683-2.470; p = 0.4246). In the patients belonging to subgroup analyses who received distal and total gastrectomy, the antiadhesion membrane was not associated with the incidence of SBO.

Conclusions

Antiadhesion membrane did not decrease SBO occurrence rate after open gastrectomy. Therefore, the use of antiadhesion membrane would not be effective for preventing SBO in gastric cancer surgery.

A nonrandomized controlled trial: long-term outcomes of LATG/LAPG for cStage I gastric cancer: Japan Clinical Oncology Group Study JCOG1401

BACKGROUND

A previous report confirmed the safety of laparoscopy-assisted total and proximal gastrectomies (LATG and LAPG) (JCOG1401). This report demonstrates the 5-year relapse-free survival (RFS) and overall survival (OS) after long-term follow-up to confirm the efficacy of these surgical methods as key secondary endpoints for cStage I gastric cancer.

METHODS

This study enrolled patients who had histologically proven gastric adenocarcinoma and were diagnosed with clinical T1N0, T1N(+), or T2N0 tumors according to the 14th edition of the Japanese Classification of Gastric Carcinoma (3rd English edition).

RESULTS

Between April 2015 and February 2017, 246 patients were enrolled, although one patient was excluded because of misregistration. Meticulous follow-up was continued for > 5 years for each patient, and the data were analyzed in March 2022. The 5-year RFS was 90.0% (95% confidence interval [CI] 85.5-93.2%), and the 5-year OS was 91.2% (95% CI 86.9-94.2%) in all enrolled patients. Grade 3 or 4 late postoperative complications were detected in 12.7% of patients.

CONCLUSIONS

This single-arm study showed that the long-term outcomes of LATG/LAPG for cStage I gastric cancer were acceptable, which is considered one of the standard treatments when performed by experienced surgeons. Trail registration UMIN000017155 ( http://www.umin.ac.jp/ctr/ ).

[Gentle Method to Elevate Left Liver Lobe in Robot Assisted Gastrectomy]

Robot-assisted gastrectomy with the Davinci XiTM has been performed in our department since August 2019. This technique requires elevation of the left liver lobe. In order to prevent perioperative liver injury and expansion of postoperative subcutaneous emphysema, we use a silicone disc(HAKKO MEDICAL Co., Ltd.)and thread to elevate the liver. After docking the Davinci system, we move the needle as follows:(ⅰ). left side peritoneum near the left triangular ligament, (ⅱ). silicone rubber(, ⅲ). center of crus(, ⅳ). silicone rubber(, ⅴ). hepatic cirrus, and(ⅵ). right side peritoneum. Both ends of the thread are guided out of the abdominal cavity from both hepatic circumflex by end-close, forming a V-shape with the center of crus at the bottom, which provides a stable and effective view of the liver. Fifty-three cases were performed after introduction of this elevation technique. Median AST and ALT on postoperative day 1 were 37(14-1,556)IU/L and 30(10- 1,676)IU/L, respectively, although small subcutaneous emphysema confined to the anterior chest and upper abdominal wall was observed in 2 patients(3.8%). No cases of extensive subcutaneous emphysema involving the neck or extremities were observed. This elevation technique protects the liver and may reduce the incidence of postoperative subcutaneous emphysema.

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.

A discrimination model by machine learning to avoid gastrectomy for early gastric cancer

Aim

Gastrectomy is recommended for patients with early gastric cancer (EGC) because the possibility of lymph node metastasis (LNM) cannot be completely denied. The aim of this study was to develop a discrimination model to select patients who do not require surgery using machine learning.

Methods

Data from 382 patients who received gastrectomy for gastric cancer and who were diagnosed with pT1b were extracted for developing a discrimination model. For the validation of this discrimination model, data from 140 consecutive patients who underwent endoscopic resection followed by gastrectomy, with a diagnosis of pT1b EGC, were extracted. We applied XGBoost to develop a discrimination model for clinical and pathological variables. The performance of the discrimination model was evaluated based on the number of cases classified as true negatives for LNM, with no false negatives for LNM allowed.

Results

Lymph node metastasis was observed in 95 patients (25%) in the development cohort and 11 patients (8%) in the validation cohort. The discrimination model was developed to identify 27 (7%) patients with no indications for additional surgery due to the prediction of an LNM-negative status with no false negatives. In the validation cohort, 13 (9%) patients were identified as having no indications for additional surgery and no patients with LNM were classified into this group.

Conclusion

The discrimination model using XGBoost algorithms could select patients with no risk of LNM from patients with pT1b EGC. This discrimination model was considered promising for clinical decision-making in relation to patients with EGC.

Randomized controlled phase III trial to investigate superiority of robot-assisted gastrectomy over laparoscopic gastrectomy for clinical stage T1-4aN0-3 gastric cancer patients (JCOG1907, MONA LISA study): a study protocol

BACKGROUND

Laparoscopic gastrectomy (LG) is considered a standard treatment for clinical stage I gastric cancer. Nevertheless, LG has some drawbacks, such as motion restriction and difficulties in spatial perception. Robot-assisted gastrectomy (RG) overcomes these drawbacks by using articulated forceps, tremor-filtering capability, and high-resolution three-dimensional imaging, and it is expected to enable more precise and safer procedures than LG for gastric cancer. However, robust evidence based on a large-scale randomized study is lacking.

METHODS

We are performing a randomized controlled phase III study to investigate the superiority of RG over LG for clinical T1-2N0-2 gastric cancer in terms of safety. In total, 1,040 patients are planned to be enrolled from 46 Japanese institutions over 5 years. The primary endpoint is the incidence of postoperative intra-abdominal infectious complications, including anastomotic leakage, pancreatic fistula, and intra-abdominal abscess of Clavien-Dindo (CD) grade ≥ II. The secondary endpoints are the incidence of all CD grade ≥ II and ≥ IIIA postoperative complications, the incidence of CD grade ≥ IIIA postoperative intra-abdominal infectious complications, relapse-free survival, overall survival, the proportion of RG completion, the proportion of LG completion, the proportion of conversion to open surgery, the proportion of operation-related death, and short-term surgical outcomes. The Japan Clinical Oncology Group Protocol Review Committee approved this study protocol in January 2020. Approval from the institutional review board was obtained before starting patient enrollment in each institution. Patient enrollment began in March 2020. We revised the protocol to expand the eligibility criteria to T1-4aN0-3 in July 2022 based on the results of randomized trials of LG demonstrating non-inferiority of LG to open surgery for survival outcomes in advanced gastric cancer.

DISCUSSION

This is the first multicenter randomized controlled trial to confirm the superiority of RG over LG in terms of safety. This study will demonstrate whether RG is superior for gastric cancer.

TRIAL REGISTRATION

The protocol of JCOG1907 was registered in the UMIN Clinical Trials Registry as UMIN000039825 ( http://www.umin.ac.jp/ctr/index.htm ). Date of Registration: March 16, 2020. Date of First Participant Enrollment: April 1, 2020.

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

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

Clinical and endoscopic features of metachronous gastric cancer with possible lymph node metastasis after endoscopic submucosal dissection and Helicobacter pylori eradication

BACKGROUND

Several studies have reported the metachronous gastric cancers (MGCs) with possible lymph node metastasis (LNM) after endoscopic submucosal dissection (ESD) and Helicobacter pylori (H. pylori) eradication in which a curative ESD had not been achieved. There have been no published reports of evaluations of the features of patients with MGC with possible LNM after ESD and H. pylori eradication.

METHODS

We identified 264 patients with 369 MGCs after H. pylori eradication among the 4354 patients with 5059 early gastric cancers (EGCs) who underwent ESD between 1999 and 2017 and divided them into two groups: patients with MGCs with possible LNM (Group I) and patients with MGCs undergone curative ESD (Group II). We retrospectively compared the features of patients with MGCs and patients with EGCs at index ESD in the two groups.

RESULT

Group I consisted of 20 patients with 21 MGCs, and Group II consisted of 244 patients with 348 MGCs. Group I lesions were significantly more common in the posterior wall than in the lesser curvature (odds ratio [OR] = 3.97; 95% confidence intervals [CI] 1.20-13.10). Development of Group I was significantly more common in patients with a body mass index (BMI) < 19.0 kg/m2 than in patients with a BMI ≥ 19.0 kg/m2 at index ESD (OR = 4.44; 95% CI 1.30-15.20).

CONCLUSIONS

During surveillance endoscopy after gastric ESD and H. pylori eradication, the posterior wall should be carefully examined to detect MGCs early. Lower BMI may be associated with the development of MGCs with possible LNM.

Efficacy of Pembrolizumab Monotherapy in Japanese Patients with Advanced Gastric or Gastroesophageal Junction Cancer

PURPOSE

Pembrolizumab demonstrated antitumor activity in programmed death ligand 1 positive (combined positive score (CPS) ≥ 1) gastric/gastroesophageal junction cancer in KEYNOTE-059 (third line or beyond), KEYNOTE-061 (second line), and KEYNOTE-062 (first line). We characterized efficacy and safety of pembrolizumab monotherapy in Japanese patients across several lines of therapy in these studies.

METHODS

This analysis was conducted in 34 patients from KEYNOTE-059 cohort 1 (all pembrolizumab), including 13 patients with CPS ≥ 1, 65 patients with CPS ≥ 1 from KEYNOTE-061 (pembrolizumab, n = 27; chemotherapy, n = 38), and 70 patients with CPS ≥ 1 from KEYNOTE-062 (pembrolizumab, n = 38; chemotherapy, n = 32). Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and safety were evaluated.

RESULTS

In KEYNOTE-059, ORR with pembrolizumab was 9%, median PFS was 2 months, and median OS was 10 months. In KEYNOTE-061, median OS was 12 months with pembrolizumab versus 10 months with chemotherapy (hazard ratio (HR), 0.67; 95% confidence interval (CI), 0.39-1.15). Median PFS (pembrolizumab vs. chemotherapy) was 2 months versus 4 months (HR, 1.21; 95% CI, 0.69-2.13); ORR was 7% versus 18%. In KEYNOTE-062, median OS was 20 months with pembrolizumab versus 18 months with chemotherapy (HR, 0.76; 95% CI, 0.43-1.33). Median PFS (pembrolizumab vs. chemotherapy) was 6 months versus 7 months (HR, 1.03; 95% CI, 0.61-1.74); ORR was 29% versus 34%.

CONCLUSIONS

The current analysis provides valuable information that anti-PD-1 therapies are worthy of further assessment for gastric cancer.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02335411 (KEYNOTE-059), NCT02370498 (KEYNOTE-061), and NCT02494583 (KEYNOTE-062).

Role of reduction gastrectomy in patients with gastric cancer with a single non-curable factor: Supplementary analysis of REGATTA trial

Background

REGATTA trial failed to demonstrate the survival benefit of reduction gastrectomy in patients with advanced gastric cancer with a single non-curable factor. However, a significant interaction was found between the treatment effect and tumor location in the subset analysis. Additionally, the treatment effect appeared to be different between Japan and Korea. This supplementary analysis aimed to elucidate the effect of reduction surgery based on tumor location and country.

Methods

Multivariable Cox regression analyses in each subgroup were performed to estimate the hazard ratio (HRadj), including the following variables as explanatory variables: country, age, sex, incurable factor, cT, cN, primary tumor, performance status, histological type, and macroscopic type.

Results

Patients (95 in Japan and 80 in Korea) were randomized to chemotherapy alone (86 patients) or gastrectomy plus chemotherapy (89 patients). The subgroup analysis according to the country revealed a worse overall survival in gastrectomy plus chemotherapy arm in Japan (hazard ratio: 1.32, 95% confidence interval: 0.85-2.05), but not in Korea (hazard ratio: 0.85.95% confidence interval: 0.52-1.40). Overall survival was better in distal gastrectomy plus chemotherapy compared with chemotherapy alone (hazard ratio = 0.69, 95% confidence interval: 0.42-1.13), and worse in total gastrectomy plus chemotherapy compared with chemotherapy alone (hazard ratio = 1.34, 95% CI: 0.93-1.94), which was more remarkable in Korea than in Japan.

Conclusions

Primary chemotherapy is a standard of care for advanced gastric cancer; however, the survival benefits from reduction by distal gastrectomy remained controversial.

Deep learning-based subtyping of gastric cancer histology predicts clinical outcome: a multi-institutional retrospective study

INTRODUCTION

The Laurén classification is widely used for Gastric Cancer (GC) histology subtyping. However, this classification is prone to interobserver variability and its prognostic value remains controversial. Deep Learning (DL)-based assessment of hematoxylin and eosin (H&E) stained slides is a potentially useful tool to provide an additional layer of clinically relevant information, but has not been systematically assessed in GC.

OBJECTIVE

We aimed to train, test and externally validate a deep learning-based classifier for GC histology subtyping using routine H&E stained tissue sections from gastric adenocarcinomas and to assess its potential prognostic utility.

METHODS

We trained a binary classifier on intestinal and diffuse type GC whole slide images for a subset of the TCGA cohort (N = 166) using attention-based multiple instance learning. The ground truth of 166 GC was obtained by two expert pathologists. We deployed the model on two external GC patient cohorts, one from Europe (N = 322) and one from Japan (N = 243). We assessed classification performance using the Area Under the Receiver Operating Characteristic Curve (AUROC) and prognostic value (overall, cancer specific and disease free survival) of the DL-based classifier with uni- and multivariate Cox proportional hazard models and Kaplan-Meier curves with log-rank test statistics.

RESULTS

Internal validation using the TCGA GC cohort using five-fold cross-validation achieved a mean AUROC of 0.93 ± 0.07. External validation showed that the DL-based classifier can better stratify GC patients' 5-year survival compared to pathologist-based Laurén classification for all survival endpoints, despite frequently divergent model-pathologist classifications. Univariate overall survival Hazard Ratios (HRs) of pathologist-based Laurén classification (diffuse type versus intestinal type) were 1.14 (95% Confidence Interval (CI) 0.66-1.44, p-value = 0.51) and 1.23 (95% CI 0.96-1.43, p-value = 0.09) in the Japanese and European cohorts, respectively. DL-based histology classification resulted in HR of 1.46 (95% CI 1.18-1.65, p-value < 0.005) and 1.41 (95% CI 1.20-1.57, p-value < 0.005), in the Japanese and European cohorts, respectively. In diffuse type GC (as defined by the pathologist), classifying patients using the DL diffuse and intestinal classifications provided a superior survival stratification, and demonstrated statistically significant survival stratification when combined with pathologist classification for both the Asian (overall survival log-rank test p-value < 0.005, HR 1.43 (95% CI 1.05-1.66, p-value = 0.03) and European cohorts (overall survival log-rank test p-value < 0.005, HR 1.56 (95% CI 1.16-1.76, p-value < 0.005)).

CONCLUSION

Our study shows that gastric adenocarcinoma subtyping using pathologist's Laurén classification as ground truth can be performed using current state of the art DL techniques. Patient survival stratification seems to be better by DL-based histology typing compared with expert pathologist histology typing. DL-based GC histology typing has potential as an aid in subtyping. Further investigations are warranted to fully understand the underlying biological mechanisms for the improved survival stratification despite apparent imperfect classification by the DL algorithm.

Acceleration of sarcopenia in elderly patients who develop asymptomatic pneumonia shadow within one year after surgery for early gastric cancer

BACKGROUND

Although early gastric cancer is curable with local treatment, the overall survival in elderly patients did not reach 80% at five years after surgery. The major cause of death in elderly patients with early gastric cancer is not cancer itself but is related to postoperative sarcopenia. Elderly patients frequently develop postoperative asymptomatic pneumonia shadow, which is associated with a poor prognosis. However, why asymptomatic pneumonia shadow worsens the prognosis remains unclear. We investigated whether sarcopenia is accelerated in patients who developed asymptomatic pneumonia shadow.

METHODS

We retrospectively examined patients of > 75 years of age who underwent R0 gastrectomy for gastric cancer and were diagnosed with T1 disease at National Cancer Center Hospital between 2005 and 2012. The diagnosis of asymptomatic pneumonia shadow was defined by diagnostic findings of pneumonia (consolidation type, reticular type, and nodular type) which were newly observed on chest computed tomography performed one year after surgery in comparison to preoperative computed tomography. Postoperative muscle loss was assessed by a computed tomography-based analysis using the L3 skeletal muscle index before and two years after surgery and the rate of decrease was calculated. Patients were classified into two groups according to the rate of decrease (cut-off value: 10%).

RESULTS

Of the 3412 patients who underwent gastrectomy in our hospital during the study period, 142 were included in this study. Asymptomatic pneumonia shadow was found in 26 patients (18%). Patients who developed asymptomatic pneumonia shadow showed a significantly greater loss of muscle volume in comparison to patients who did not develop asymptomatic pneumonia shadow. In the multivariate analysis, total gastrectomy and asymptomatic pneumonia shadow were the independent risk factors for severe muscle loss. However, there was no significant difference in prognosis between the two groups.

CONCLUSIONS

Sarcopenia was accelerated in elderly patients who developed asymptomatic pneumonia shadow after surgery for early gastric cancer. However, the poor prognosis in these patients may not be related to accelerated sarcopenia.

Incidence and risk factors for venous thromboembolism in the Cancer-VTE Registry stomach cancer subcohort

BACKGROUND

The Cancer-VTE Registry was a large-scale, multicenter, prospective registry designed to investigate real-world data on venous thromboembolism (VTE) incidence and risk factors in adult Japanese patients with solid tumors. This pre-specified subgroup analysis aimed to estimate the incidence of VTE, including VTE types other than symptomatic VTE, and identify risk factors of VTE in stomach cancer from the Cancer-VTE Registry.

METHODS

Stage II-IV stomach cancer patients who planned to initiate cancer therapy and underwent VTE screening within 2 months before registration were enrolled.

RESULTS

Of 1,896 patients enrolled, 131 (6.9%) had VTE at baseline, but 96.2% were asymptomatic. Female sex, age ≥ 65 years, VTE history, and D-dimer > 1.2 μg/mL were independent risk factors of VTE at baseline. Notably, patients with D-dimer > 1.2 µg/mL at the time of cancer diagnosis had an approximately 20-fold risk of VTE. During follow-up, event incidences were symptomatic VTE, 0.3%; incidental VTE requiring treatment, 1.1%; composite VTE, 1.4%; bleeding, 1.6%; cerebral infarction/transient ischemic attack/systemic embolic events, 0.7%; and all-cause death, 15.0%. The incidence of all-cause death was higher in patients with VTE vs without VTE at baseline (adjusted hazard ratio 1.67; 95% confidence interval 1.21-2.32; p = 0.002).

CONCLUSIONS

VTE prevalence at the time of cancer diagnosis was not negligible and was extremely high when the patients had high D-dimer. VTE screening by D-dimer before starting cancer treatment is advisable, even for asymptomatic patients, regardless of whether the patient is undergoing surgery or chemotherapy.

TRIAL REGISTRATION

UMIN000024942.

Perioperative TAS-118 plus oxaliplatin in patients with locally advanced gastric cancer: APOLLO-11 study

BACKGROUND

We investigated the feasibility of perioperative chemotherapy with S-1 and leucovorin (TAS-118) plus oxaliplatin in patients with locally advanced gastric cancer.

METHODS

Patients with clinical T3-4N1-3M0 gastric cancer received four courses of TAS-118 (40-60 mg/body, orally, twice daily for seven days) plus oxaliplatin (85 mg/m2, intravenously, day one) every two weeks preoperatively followed by gastrectomy with D2 lymphadenectomy, followed by postoperative chemotherapy with either 12 courses of TAS-118 monotherapy (Step 1) or eight courses of TAS-118 plus oxaliplatin (Step 2). The primary endpoints were completion rates of preoperative chemotherapy with TAS-118 plus oxaliplatin and postoperative chemotherapy with TAS-118 monotherapy (Step 1) or TAS-118 plus oxaliplatin (Step 2).

RESULTS

Among 45 patients enrolled, the preoperative chemotherapy completion rate was 88.9% (90% CI 78.0-95.5). Major grade ≥ 3 adverse events (AEs) were diarrhoea (17.8%) and neutropenia (8.9%). The R0 resection rate was 95.6% (90% CI 86.7-99.2). Complete pathological response was achieved in 6 patients (13.3%). Dose-limiting toxicity was not observed in 31 patients receiving postoperative chemotherapy (Step 1, n = 11; Step 2, n = 20), and completion rates were 90.9% (95% CI 63.6-99.5) for Step 1 and 80.0% (95% CI 59.9-92.9) for Step 2. No more than 10% of grade ≥ 3 AEs were observed in  patients receiving Step 1. Hypokalaemia and neutropenia occurred in 3 and 2 patients, respectively, receiving Step 2. The 3-year recurrence-free and overall survival rates were 66.7% (95% CI 50.9-78.4) and 84.4% (95% CI 70.1-92.3), respectively.

CONCLUSIONS

Perioperative chemotherapy with TAS-118 plus oxaliplatin with D2 gastrectomy is feasible.

Feasibility and Safety of Adjuvant Chemotherapy for Resected Colorectal Cancer in Patients With Renal Insufficiency: A Pooled Analysis of Individual Patient Data from Five Japanese Large-scale Clinical Trials

BACKGROUND/AIM

The incidence of chemotherapy-related adverse events in colorectal cancer patients with renal insufficiency has been compared to patients with normal renal function in only a few studies. The purpose of this analysis was to verify the feasibility and safety of adjuvant chemotherapy for postoperative colorectal cancer patients with renal insufficiency.

PATIENTS AND METHODS

Adverse events and discontinuation of adjuvant chemotherapy for patients with curatively resected locally advanced colorectal cancer were examined using a combined database of individual patient data obtained from five large-scale clinical trials (n=4,106). The renal function of patients was classified into Level (L) 1-2: ≥60 ml/min and L3-4: <60 ml/min.

RESULTS

As Grade 3 adverse events, hematological toxicities, such as neutropenia and anemia, and gastrointestinal disorders, such as diarrhea and vomiting, were significantly more frequent in the L3-4 group. Moreover, the time-to-treatment discontinuation in the L3-4 group was higher (hazard ratio=1.21, p=0.0012). T factor, N factor, and creatinine clearance level were found to be independent risk factors for the discontinuation of adjuvant chemotherapy. In the subgroup analysis of FOLFOX, neutropenia and diarrhea were significantly common in the L3-4 group, but neurotoxicities were not different. There was no significant difference in the discontinuation of adjuvant FOLFOX.

CONCLUSION

Adverse events of adjuvant chemotherapy in patients with resected colorectal cancer were associated with renal insufficiencies. Since adverse events have the potential to shorten the duration of treatment, especially when using chemotherapy without oxaliplatin, careful management, including dose reduction, may be important in patients with renal insufficiency.

Can Clinical Stage in the 8th Edition of the Union for International Cancer Control TNM Classification Stratify the Prognosis of Patients Undergoing Curative Surgery for Siewert Type II/III Adenocarcinoma of the Esophagogastric Junction?

BACKGROUND/AIM

Clinical staging in the eighth edition of the Union for International Cancer Control TNM classification (TNM8) is reported to predict the prognosis of patients with gastric cancer. However, there have been no reports on using the TNM8 for prognostic stratification of patients with adenocarcinoma of the esophagogastric junction (AEG). This study aimed to investigate whether it was possible to stratify the prognosis of patients who underwent curative surgery for Siewert type II/III AEG according to the TNM8 clinical stage (cStage).

PATIENTS AND METHODS

This study included patients with Siewert type II/III AEG who underwent curative surgery between 2000 and 2019 at Kanagawa Cancer Center. Those who received neoadjuvant chemotherapy were excluded. We investigated the survival of patients with AEG of each TNM8 cStage.

RESULTS

This study included 138 patients, among whom 102 (74%) had Siewert type II and 36 (26%) had Siewert type III AEG. A total of 50, 38, 43, and seven patients were classified with cStage I, II, III, and IV, respectively. The median duration of follow-up of the survivors was 54.7 months. The 5-year overall survival rate of the entire cohort was 65.8%, whereas for patients with cStage I, II, III and IV was 81.6%, 69.0%, 54.3% and 14.3%, respectively. The hazard ratio with reference to cStage I was 1.83, 3.07, and 8.13 for cStage I, III, and IV, respectively, increasing in a stepwise manner.

CONCLUSION

TNM8 Clinical staging is able to stratify the prognosis of patients with Siewert type II/III AEG.

The clinical impacts of postoperative complications after colon cancer surgery for the clinical course of adjuvant treatment and survival

AIM

We investigated whether or not postoperative complications (POCs) themselves have a negative survival impact or indirectly worsen the survival due to insufficient adjuvant chemotherapy in a pooled analysis of two large phase III studies performed in Japan PATIENTS AND METHODS: The study examined the patients who enrolled in 1304, phase III study comparing the efficacy of 6 and 12 months of capecitabine as adjuvant chemotherapy for stage III colon cancer patients and in 882, a phase III study to confirm the tolerability of oxaliplatin, fluorouracil, and l-leucovorin in Japanese stage II/III colon cancer patients. In our study, POCs were defined as the following major surgical complications: anastomotic leakage, pneumonia, bowel obstruction/ileus, surgical site infection, postoperative bleeding, urinary tract infection, and fistula. Patients were classified as those with POCs (C group) and those without POCs (NC group).

RESULTS

A total of 2095 patients were examined in the present study. POCs were observed in 169 patients (8.1%). The overall survival (OS) rates at 5 years after surgery were 75.3% in the C group and 86.5% in the NC group (p = 0.0017). The hazard ratio of POCs for the OS in multivariate analysis was 1.70 (95% confidence interval, 1.19 to 2.45; p = 0.0040). The time to adjuvant treatment failure (TTF) of adjuvant chemotherapy was similar between the groups, being 68.6% in the C group and 67.1% in the NC group for the 6-month continuation rate of adjuvant chemotherapy. The dose reduction rate of adjuvant chemotherapy and adjuvant treatment suspension rate were also similar between the groups (C vs. NC groups: 45.0% vs. 48.7%, p = 0.3520; and 52.7% vs. 55.0%, p = 0.5522, respectively).

CONCLUSION

POCs were associated with a poor prognosis but did not affect the intensity of adjuvant chemotherapy. These results suggested that POCs themselves negatively influence the survival.

Possible candidates for splenic hilar nodal dissection among patients with upper advanced gastric cancer without invasion of the greater curvature

BACKGROUND

Spleen preserving D2 total gastrectomy without dissection of the splenic hilar nodes (#10) is a standard operation for upper advanced gastric cancer without invasion of the greater curvature (UGC-wGC). However, some patients with #10 metastasis have survived after splenectomy with dissection of #10. This study explored possible candidates for dissection of #10 among patients with UGC-wGC by examining the metastatic rate and the therapeutic index.

METHODS

This study retrospectively reviewed data of patients treated in National Cancer Center Hospital (Japan) between 2000 and 2012. We applied the following inclusion criteria: (1) ≥ D2 total gastrectomy with splenectomy, (2) UGC-wGC, and (3) gastric adenocarcinoma histology. Univariate and multivariate analyses were performed to identify risk factors for #10 metastasis.

RESULTS

A total of 366 patients were examined; #10 metastasis was observed in 4.4% (16/366). The multivariate analysis revealed that location (posterior vs. others, P = 0.025) and histology (undifferentiated vs. differentiated, P = 0.048) were significant factors for #10 metastasis among sex, age, tumor size, dominant circumferential location, macroscopic type, depth of invasion, and histology. The incidence of #10 metastasis was 14.9% (7/47) for tumors located on the posterior wall with undifferentiated type histology. The 5-year overall survival rate of these patients was 42.9%, and the therapeutic index was 6.38, which was the second highest value among the second-tier nodal stations.

CONCLUSION

Even for upper advanced gastric cancer without invasion of the greater curvature, dissection of #10 could be justified for tumors located on the posterior wall with undifferentiated type histology.

Pembrolizumab or pembrolizumab plus chemotherapy versus standard of care chemotherapy in patients with advanced gastric or gastroesophageal junction adenocarcinoma: Asian subgroup analysis of KEYNOTE-062

OBJECTIVE

First-line pembrolizumab with/without chemotherapy versus chemotherapy was evaluated in programmed death ligand 1 combined positive score ≥1, locally advanced/unresectable or metastatic gastric cancer/gastrooesophageal junction cancer in the KEYNOTE-062 study. We present results for patients enrolled in Asia.

METHODS

Eligible patients were randomly assigned 1:1:1 to pembrolizumab 200 mg, pembrolizumab plus chemotherapy (cisplatin + 5-fluorouracil or capecitabine) or placebo plus chemotherapy Q3W. End points included overall survival (primary) in combined positive score ≥1 and combined positive score ≥10 populations and safety and tolerability (secondary).

RESULTS

A total of 187 patients were enrolled in Asia (pembrolizumab, n = 62; pembrolizumab plus chemotherapy, n = 64; chemotherapy, n = 61). Compared with the global population, higher proportions of patients had Eastern Cooperative Oncology Group performance status 0 and a diagnosis of stomach cancer. In the programmed death ligand 1 combined positive score ≥1 population, median overall survival was numerically longer with pembrolizumab versus chemotherapy (22.7 vs 13.8 months; hazard ratio, 0.54; 95% confidence interval, 0.35-0.82) and pembrolizumab plus chemotherapy versus chemotherapy (16.5 vs 13.8 months; hazard ratio, 0.78; 95% confidence interval, 0.53-1.16). In the programmed death ligand 1 combined positive score ≥10 population, median overall survival was also numerically longer with pembrolizumab versus chemotherapy (28.5 vs 14.8 months; hazard ratio, 0.43; 95% confidence interval, 0.21-0.89) and pembrolizumab plus chemotherapy versus chemotherapy (17.5 vs 14.8 months; hazard ratio, 0.86; 95% confidence interval, 0.45-1.64). The grade 3-5 treatment-related adverse event rate was 19.4%, 75.8% and 64.9% for patients receiving pembrolizumab, pembrolizumab plus chemotherapy and chemotherapy, respectively.

CONCLUSIONS

This post hoc analysis showed pembrolizumab monotherapy was associated with numerically improved overall survival and a favourable tolerability profile versus chemotherapy in Asians with programmed death ligand 1-positive advanced gastric cancer/gastrooesophageal junction cancer.This study is registered with ClinicalTrials.gov, NCT02494583.

Frequency of lymph node metastasis according to tumor location in clinical T1 early gastric cancer: supplementary analysis of the Japan Clinical Oncology Group study (JCOG0912)

BACKGROUND

The frequency of lymph node metastases per lymph node site in early gastric cancer has not been well clarified from the data based on prospective studies. This exploratory analysis aimed to determine the frequency and location of lymph node metastases in clinical T1 gastric cancer using the data from JCOG0912 to investigate the validity of the extent of standard lymph node dissection defined in Japanese guidelines.

METHODS

This analysis included 815 patients with clinical T1 gastric cancer. The proportion of pathological metastasis was identified for each lymph node site per tumor location (middle third and lower third) and four equal parts of the gastric circumference. The secondary aim was identification of the risk factor for lymph node metastasis.

RESULTS

Eighty-nine patients (10.9%) had pathologically positive lymph node metastases. Although the overall frequency of metastases was low (0.3-5.4%), metastases were widely located in each lymph node sites when primary lesion was in the middle third of the stomach. No. 4sb and 9 showed no metastasis when primary lesion was in the lower third of the stomach. Lymph node dissection of metastatic nodes resulted in a 5-year survival in more than 50% of patients. A tumor greater than 3 cm and a T1b tumor were associated with lymph node metastasis.

CONCLUSIONS

This supplementary analysis demonstrated that nodal metastasis from early gastric cancer is widely and disorderly not depending on the location. Thus, systematic lymph node dissection is necessary to cure the early gastric cancer.

Five-year follow-up results of a randomized phase III trial comparing 4 and 8 courses of S-1 adjuvant chemotherapy for pathological stage II gastric cancer: JCOG1104 (OPAS-1)

381

Background: Postoperative S-1 (80 mg/m2/day for 4 weeks and 2 weeks rest in one course) for 1 year corresponding to 8 courses is a standard adjuvant chemotherapy for pathological stage (pStage) II gastric cancer. To shorten the duration of S-1 chemotherapy, we conducted a phase III trial to confirm non-inferiority in relapse-free survival (RFS) of 4 courses of S-1 to 8 courses of S-1 for pStage II gastric cancer. When 590 patients were enrolled, the study was closed at the first interim analysis because of futility. The RFS at 3 years was 89.8% for 4-courses and 93.1% for 8-courses (HR 1.84, 95% confidence interval (CI) 0.93-3.63). This is a final 5-year follow-up results of this study. Methods: Key eligibility criteria were pStage II except for T1 and T3N0 (7th edition of TNM), ECOG performance status 0-1, R0 resection with D2 lymph node dissection for >clinical stage (cStage) II or D1+ lymph node dissection for cStage I, within 7 weeks after surgery, and age between 20 and 80 years. The total sample size was determined to be 1,000 with a 3-year RFS of 85% in both arms and non-inferiority margin of hazard ratio (HR) of 1.37, with one-sided alpha of 5% and 80% power. Results: Between Feb 2012 and Mar 2017, 590 patients, 295 for each arm, were enrolled. When closing the study, the patients who were allocated to the 4-courses arm were informed of the primary results and the recommendation to continue S-1 until 8 courses as an off-protocol when they were receiving S-1. The cut-off date for the final follow-up data was March 22, 2022 with a median follow-up period for surviving patients of 6.0 years (IQR; 5.0-7.2). In 4-courses arm, 27 patients were receiving S-1 when the study was closed at the interim analysis. Among them, 22 patients expressed their will to continue until 8 courses. The RFS at 3/5 years was 90.1%/85.6% for 4-courses and 92.2%/87.7% for 8-courses (HR 1.27, 95% CI 0.85-1.89). The overall survival at 3/5 years was 93.2%/88.6 for 4-courses and 94.9%/89.7 for the 8-courses (HR 1.12, 95% CI 0.72-1.75). The HR of the cumulative incidence of the recurrence was 1.38 (95% CI 0.85-2.24) for the 4-courses against 8-courses. Recurrence was frequently observed in patients who received up to 4 courses of S-1 (38 for 4-courses vs. 28 for 8 courses). The HR of the cumulative incidence of the peritoneal recurrence was 1.54 (95% CI 0.82-2.89) for the 4-courses against 8-courses. Conclusions: This final follow-up data confirmed the primary results presented at the interim analysis. S-1 adjuvant chemotherapy for 1 year for pStage II gastric cancer is highly recommended. Clinical trial information: 000007306 .

Survival results by the prospectively determined clinical staging for locally advanced gastric cancer: An ancillary study of JCOG1302A (JCOG1302A2)

392

Background: Recently, neoadjuvant chemotherapy has been recognized as a promising strategy to improve the survival of patients with advanced gastric cancer. On the other hand, given the adverse events and treatment cost of chemotherapy, the candidate for NAC should be limited to patients who can benefit from NAC. In fact, as previously reported, the proportion of pathological stage I tumors was 50.4% in cT2N0, 38.7% in cT2N(+), 26.7% in cT3N0, 10.6% in cT3N(+), 9.0% in cT4aN0, and 3.0% in cT4aN(+). Therefore, clinical staging before initiation of treatment is increasingly important for determining therapeutic strategy. However, the long-term survival stratified by the prospectively-determined clinical stage has not been fully investigated. Methods: Between July 2013 and November 2014, the JCOG1302A examined 1260 patients with a clinical diagnosis of cT2/T3/T4, cN0/N1/N2/N3, M0, except for diffuse large tumors like linitis plastica and extensive bulky nodal diseases according to the Japanese Classification of Gastric Carcinoma (3rd English edition). The cT diagnosis was made by upper gastrointestinal endoscopy and comprehensive findings on upper abdominal contrast CT scan with 1 or 5 mm slice thickness. Lymph nodes with a shortest dimension greater than 8 mm or a longest dimension greater than 10 mm were defined as positive for metastasis. In this follow-up study, the survival data by stratifying the clinical staging were evaluated. Results: Among 1260 patients, survival data of 1177 were analyzed. With a median follow-up for 821 surviving patients of 6.0 years, the 5y-OS was 82.1% (95% CI, 77.3-85.9) in cT2 (n=319), 72.7% (68.2-76.6) in cT3 (n=450), 60.0% (54.9-64.7) in cT4a (n=401), and 40.0% (5.2-75.3) in cT4b (n=6), while that was 78.0% (74.2-81.2) in cN0 (n=560), 70.6% (65.4-75.2) in cN1 (n=350), 59.1% (52.5-65.1) in cN2 (n=241), and 28.4% (12.7-46.5) in cN3 (n=26), respectively. When combined with cT and cN, 5y-OS was 83.5% (77.8-87.8) in cT2N0 (n=226), 77.2% (71.0-82.2) in cT3N0 (n=232), 66.8% (56.3-75.2) in cT4aN0 (n=100), 100% in cT4bN0 (n=1), 78.7% (68.6-85.8) in cT2N(+)(n=93), 68.0% (61.1-73.8) in cT3N(+)(n=218), 57.7% (51.7-63.2) in cT4aN(+)(n=301), and 25.0% (0.9-66.5) in cT4bN(+)(n=5). Conclusions: Both the survival and the proportion of overdiagnosis of stage I patients in patients with cT4aN0, categorized as cstage IIB, was almost same as in those cT3N(+) categorized as cstage III. In considering the candidate for further treatment development of NAC with high toxic regime in future, cT3N(+) and cT4aN0 should be considered as equivalent category.

The optimal extent of lymph node dissection for gastric cancer with para-aortic lymph node metastases

413

Background: Gastric cancer (GC) with para-aortic lymph node (PAN) metastasis is diagnosed as stage IV and basically treated with chemotherapy. Recently, D2 and PAN dissection after neoadjuvant chemotherapy (NAC) was reportedly effective when PAN metastasis was limited within #16a2/b1 area. However, PAN dissection is highly invasive surgical procedure and it still remains unclear whether PAN dissection contributes to the survival for these tumors. This study aimed to determine the optimal extent of lymph node dissection for these tumors focusing on survival benefit of PAN dissection. Methods: The study examined patients who received radical gastrectomy with D2 and PAN dissection after NAC for gastric cancer with PAN metastasis (#16a2/b1) from 2004 to 2015. Survival benefit of lymph node dissection was estimated using therapeutic value index (TI). TI was calculated by multiplication of incidence of metastasis and 5-year survival rate of patients with metastasis for each lymph node area. TI of D2 dissection area (TI-D2) and PAN area (TI-PAN) was calculated separately. Overall survival (OS) was calculated in patients who had metastasis to PAN pathologically after surgery (pPAN+ group) and those who had not (pPAN- group). The recurrence site was also examined. Results: Thirty-two patients were analyzed. TI-D2 and TI-PAN were 15.6 and 0.0, respectively. 5y-OS was 81.0% in pPAN- group (21 cases) but was 0.0% in pPAN+ group (11 cases). The most frequent recurrence site was the lymph nodes (82.4% of all recurrences). Among lymph node recurrence, almost all recurrence patterns included the PANs (85.7% of lymph node recurrence). Conclusions: The prognosis was extremely poor when tumor cells remained on PAN after NAC. In these cases, PAN recurrence was seen most frequently even after PANs had been dissected. Patients with PAN could have the chance for the cure only when tumor cells on PAN was completely eliminated by NAC. It is unclear whether they actually needed PAN dissection for pathologically negative PAN. The optimal extent of lymph node dissection after NAC might be D2 for GC with PAN metastasis.

A phase II study of preoperative chemotherapy with docetaxel, oxaliplatin, and S-1 followed by gastrectomy with D2 plus para-aortic nodal dissection for gastric cancer with extensive lymph node metastasis: JCOG1704

354

Background: Prognosis of gastric cancer (GC) with extensive lymph node metastasis (ELM) is poor due to unresectability even without distant metastases. We conducted a phase II study to evaluate the safety and efficacy of preoperative chemotherapy with docetaxel (D), oxaliplatin (O), and S-1 (S) followed by extended gastrectomy. Methods: Eligibility criteria included histologically proven adenocarcinoma of the stomach; bulky nodal involvement around major branched arteries to the stomach (Bulky N) and/or para-aortic nodal metastases (PAN); cM0 (except para-aortic nodes); negative lavage cytology; not linitis plastica type; PS of 0 or 1; 20-75 years old. Patients received three 21-day cycles of preoperative chemotherapy of D (40 mg/m2 on day 1), O (100 mg/m2 on day 1), and S (80-120 mg /body from day 1 to day 14), and then underwent gastrectomy with D2 plus para-aortic nodal dissection. After surgery, patients received adjuvant chemotherapy with S-1 for 1 year. Primary endpoint was major pathological response rate, defined by the disappearance of more than two-thirds of the primary tumor. Expected and threshold value of major pathological response was set at 40% and 25%, respectively. Sample size was calculated to be 50 based on a one-sided alpha of 0.1, power of 0.8 and single-arm phase II study using a Southwest Oncology Group (SWOG) two-stage design. Results: Between Oct 2018 and Mar 2022, 47 patients were enrolled, of whom 46 were eligible for efficacy analysis. The median age was 67 years. The pathological type was differentiated in 33 patients and undifferentiated in 14. Twenty patients had only bulky N, 17 had only PAN, and 10 had both of bulky N and PAN. Clinical stage was III in 19 and IV in 28 patients. Except one patient refused chemotherapy, 46 patients (45 in three cycles and 1 in one cycle) completed preoperative DOS. Forty-four patients (94%) underwent gastrectomy, including 23 distal gastrectomy and 21 total gastrectomy, and 43 (91%) had an R0 resection. Major pathological response was confirmed in 26 of 46 patients (57% with 80% CI: 46-67), including pCR of 24%, which met the statistical significance (p<0.0001). According to the Becker’s criteria, grade 3 was 13, grade 2 was 12, grade 1b was 7, and grade 1a was 11. DOS-related grade 3/4 toxicities included neutropenia in 11 patients (24%), anorexia in 7 (16%), diarrhea in 4 (9%), and febrile neutropenia in 4 (9%). Surgery-related grade 3/4 toxicities were abdominal abscess in 5 (12%) and pancreatic fistula in 3 (7%). No treatment-related death was observed. Conclusions: Preoperative DOS followed by gastrectomy with D2 plus para-aortic nodal dissection is safe, feasible, and effective for GC with ELM. Clinical trial information: jRCTs031180028 .

The new prognostic index of advanced gastric cancer using the data from JCOG1013

342

Background: We previously reported that performance status (PS) ≥1, no prior gastrectomy, number of metastatic sites ≥2, and high serum ALP level are poor prognosis factors and proposed a JCOG prognostic index by analyzing the data of advanced gastric cancer (AGC) patients enrolled in JCOG9912 (Takahari D et al. Oncologist 2014). Recently, Neutrocyte/ Lymphocyte Ratio (NLR) and diffuse type of cancer have also been reported to be prognostic factors of AGC. Methods: Prognostic factors were assessed in patients with AGC who enrolled in JCOG1013, the phase III study comparing docetaxel, cisplatin, and S-1 (DCS) versus cisplatin and S-1 (CS) in first-line treatment (Yamada Y et al. Lancet Gastroenterol Hepatol. 2019) was retrospectively evaluated using a Cox proportional regression model. The overall adequacy of risk prediction in the modified JCOG prognostic index and the original index were assessed by C-statistics. Results: Among 741 patients, 730 with all data for this analysis were selected. The median overall survival (OS) was 14.9 months (95% confidence interval [CI], 14.1–15.8). The median OS of the good (n=233), moderate (n=444), and poor (n=53) risk groups by the original JCOG index was 19.0, 14.2, and 9.1 months, respectively. The HRs compared with the good group were 1.59 [95% CI, 1.33–1.89; p < 0.0001] in the moderate group, and 2.47 [95% CI, 1.81–3.38; p < 0.0001] in the poor group with C-statistics of 0.572. In the multivariable analysis of 7 factors which showed p<0.1 in univariable analysis, PS ≥1 (hazard ratio [HR], 1.490; 95% CI, 1.264–1.755; p < 0.0001), diffuse type (HR, 1.337; 95% CI, 1.122–1.594; p = 0.012), number of metastatic sites ≥2 (HR, 1.256; 95% CI, 1.058–1.492; p = 0.0093), and NLR≥3.1 (HR, 1.539; 95% CI, 1.309–1.809; p < 0.0001) were significantly associated with worse prognosis, whereas no prior gastrectomy, peritoneal metastasis, and high serum ALP level were not. As the modified JCOG prognostic index, patients were classified into three groups according to the number of these four newly identified prognostic risk factors: good (no), moderate (1 or 2), and poor (3 or 4). Median OS of the good (n=221), moderate (n=441), and poor (n=68) risk groups was 20.6, 13.7, and 9.4 months, respectively. The HRs compared with the good group were 1.70 [95% CI, 1.42–2.03; p < 0.0001] in the moderate group, and 3.11 [95% CI, 2.33–4.14; p < 0.0001] in the poor group with C-statistics of 0.591. Three groups by the modified JCOG prognostic index also showed clear separation of OS in either subgroup of DCS or CS. Conclusions: Modified JCOG prognostic index, including NLR ≥3.1 and diffuse type instead of no prior gastrectomy and high serum ALP level, showed clear stratification of OS in JCOG1013.

Single-arm phase II trial to evaluate the safety of laparoscopic/robotic total gastrectomy with spleen-preserving splenic hilar dissection for locally advanced proximal gastric cancer that invades the greater curvature: JCOG1809

TPS479

Background: The standard treatment for locally advanced proximal gastric cancer invading the greater curvature is “open total gastrectomy combined with splenectomy” (OTG+S) aiming for whole clearance of the splenic hilar lymph nodes. However, its pertinent postoperative severe complication (e.g. pancreatic fistula) is problematic. An objective of this study is to evaluate the safety of “laparoscopic or robotic total gastrectomy with spleen-preserving splenic hilar dissection” (LRSHD) as a new treatment option which has a potential to reduce surgical morbidity, subsequently to replace the current standard treatment, OTG+S. Methods: This is a multicenter single-arm phase II trial. The main eligibility criteria are as follows; clinical T2-4a resectable locally advanced proximal gastric adenocarcinoma that invades the greater curvature; without obvious lymph node metastasis at the splenic hilum nor direct invasion to the spleen/splenogastric ligament. Protocol treatment is laparoscopic or robotic total gastrectomy with splenic hilar lymph node dissection (D2 + No.10 lymphadenectomy according to the Japanese guidelines) in which the spleen is preserved with skeletonizing the splenic vessels. Quality control of surgery is assured by surgeon’s qualification and central peer review of intraoperative photo at the splenic hilum after dissection. The primary endpoint is the proportion of postoperative pancreatic fistula and/or intra-abdominal abscess formation with Clavien-Dindo Grade III or higher (within 30 days after surgery). Secondary endpoints are intraoperative blood loss, operation time, mortality, overall postoperative complication, number of yield splenic hilar nodes, number of metastatic splenic hilar nodes, conversion to splenectomy, conversion to laparotomy, relapse-free survival, and overall survival. Sample size was set as 85 patients to obtain 80% power considering that 15% of patients are judged as unresectable intraoperatively, with the hypothesis that the primary endpoint would have an expected value of 7% and a threshold value of 16% in one-sided alpha of 0.1. Planned accrual period is 5 years. The accrual began in August 2019. As of August 2022, 53 of the planned 85 patients (62.4%) have been enrolled. When the safety of LRSHD is proved by this study, a non-inferiority phase III trial will be consequently launched. Clinical trial registry number: UMIN000037580. Clinical trial information: UMIN000037580 .

Long-term outcomes after laparoscopy-assisted total or proximal gastrectomy with nodal dissection for clinical stage I gastric cancer: Japan Clinical Oncology Group study (JCOG1401)

305

Background: JCOG0912 supports the non-inferiority of laparoscopy-assisted distal gastrectomy (LADG) compared with open distal gastrectomy (ODG) for clinical stage I gastric cancer relapse-free survival (RFS), suggesting that LADG should be considered a standard treatment option when performed by experienced surgeons. No prospective study evaluating laparoscopy-assisted total gastrectomy (LATG) and laparoscopy-assisted proximal gastrectomy (LAPG) has been completed in terms of both safety and long-term survival. Considering that the results of the phase III trial to evaluate the long-term outcome of LADG (JCOG0912) could guarantee that of LATG/LAPG, we conducted a single-arm confirmatory trial (JCOG1401) to evaluate the safety of LATG/LAPG for clinical stage I proximal gastric cancer and JCOG1401 confirmed the safety of LATG/LAPG. Long-term outcomes as the secondary endpoints of this study are reported here after 5-year follow-up period. Methods: Laparoscopic operators were limited to credentialed surgeons. The extent of nodal dissection was selected based on the Gastric Cancer Treatment Guidelines in Japan. The primary endpoint was the proportion of grade 2 (CTCAE ver. 4.0) or greater esophageal anastomotic leak. The sample size was determined to be 245 considering a threshold of 8% and expected value of 3% with a one-sided alpha error of 2.5% and statistical power of 90%. The secondary endpoints were overall survival (OS) and RFS. Results: Between April 2015 and February 2017, 245 patients were enrolled. Among them, 1 patient was excluded from safety analysis due to ineligible. LATG/LAPG was performed in 195/49. 170/47/17/8/2 patients had pStage IA/IB/II/IIIA/IIIB disease and 190/31/15/8 patients had pT1/T2/T3/T4 disease, respectively. Grade 2 or greater esophageal anastomotic leak was 2.5% (6/244) (95% CI 0.9-5.3), as previously reported. 5-year OS was 91.2% (95% CI 86.9-94.2). 5-year RFS was 90.0% (95% CI 85.5-93.2). Among 22 deaths, 14 patients died without recurrence and 8 patients died with recurrence. Twelve recurrences were observed in 5/2/4/1 patients for pT1/T2/T3/T4. The sites of recurrence were peritoneal metastasis in 2 cases, hematogenous metastasis in 9 cases (liver: 6, bone: 2, lung: 1), and other in 1 case. Conclusions: The long-term outcomes of LATG/LAPG for Stage I gastric cancer patients were excellent and seem comparable to those of open procedures. Similar to JCOG0912, JCOG1401 guarantee the long-term survival of LATG/LAPG. Clinical trial information: UMIN000017155 .

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.

Should the splenic hilar lymph node be dissected for the management of adenocarcinoma of the esophagogastric junction?

BACKGROUND

Splenic hilar lymphadenectomy is not recommended for advanced proximal gastric cancer that does not invade the greater curvature according to the results of the previous studies. The efficacy of splenic hilar lymphadenectomy for type II and type III adenocarcinomas of the esophagogastric junction and easy spread to the greater curvature of the stomach remains unclear. This study aimed to investigate the efficacy of splenic hilar lymphadenectomy and identify the risk factors for metastasis to splenic hilar nodes.

METHODS

We examined patients who underwent R0/1 gastrectomy for Siewert types II and III at a single high-volume center in Japan. We analyzed the metastatic incidence, therapeutic value index, and risk factors for splenic hilar lymph node metastasis.

RESULTS

We examined 126 patients (74, type II; 52, type III). Splenectomy was performed in 76 patients. Metastatic incidence and the therapeutic value index of splenic hilar lymph nodes in patients with type II and type III tumors were 4.5% and 0, and 21.9% and 9.4, respectively. In the patients who underwent splenectomy, we identified Siewert type III tumors (odds ratio: 6.93, 95% confidence interval: 1.24-38.8, p = 0.027) and tumor location other than the lesser curvature (odds ratio: 7.36, 95% confidence interval: 1.32-41.1, p = 0.023) to be independent risk factors. The metastatic incidence (46.2%) and therapeutic value index (15.4) were high in patients with both risk factors.

CONCLUSIONS

Splenic hilar lymphadenectomy may contribute to the survival of patients with Siewert type III tumors, especially when the predominant location is not the lesser curvature.

Establishment of preanalytical conditions for microRNA profile analysis of clinical plasma samples

The relationship between the expression of microRNAs (miRNAs) in blood and a variety of diseases has been investigated. MiRNA-based liquid biopsy has attracted much attention, and cancer-specific miRNAs have been reported. However, the results of analyses of the expression of these miRNAs vary among studies. The reproduction of results regarding miRNA expression levels could be difficult if there are differences in the data acquisition process. Previous studies have shown that the anticoagulant type used during plasma preparation and sample storage conditions could contribute to differences in measured miRNA levels. Thus, the impact of these preanalytical conditions on comprehensive miRNA expression profiles was examined. First, the miRNA expression profiles of samples obtained from healthy volunteers were analyzed using next-generation sequencing. Based on an analysis of the library concentration, human genome identification rate, ratio of unique sequences and expression profiles, the optimal preanalytical conditions for obtaining highly reproducible miRNA expression profiles were established. The optimal preanalytical conditions were as follows: ethylenediaminetetraacetic acid (EDTA) as the anticoagulant, whole-blood storage at room temperature within 6 hours, and plasma storage at 4°C or -20°C within 30 days. Next, plasma samples were collected from 60 cancer patients (3 facilities × 20 patients/facility), and miRNA expression profiles were analyzed. There were no significant differences in measurements except in the expression of erythrocyte-derived hsa-miR-451a. However, the variation in hsa-miR-451a levels was smaller among facilities than among individuals. This finding suggests that samples obtained from the same facility could show significantly different degrees of hemolysis across individuals. We found that the standardization of anticoagulant use and storage conditions contributed to reducing the variation in sample quality across facilities. The findings from this study could be useful in developing protocols for collecting samples from multiple facilities for cancer screening tests.

Late complication after gastrectomy for clinical stage I cancer: supplementary analysis of JCOG0912

BACKGROUND

Late complications following gastric cancer surgery, including postgastrectomy syndromes, are complex problems requiring a solution. Reported risk factors for developing late complications include surgery-related factors, such as the surgical approach and the extent of resection and reconstruction. However, this has not been assessed in a prospective study with a large sample size. Therefore, this study aimed to evaluate associations between surgery-related factors and the development of late complications. Data from the JCOG0912 trial were used. It compared laparoscopy-assisted distal gastrectomy (LADG) to open distal gastrectomy (ODG) in clinical stage I gastric cancer patients.

METHODS

This study included 881/921 patients enrolled in the JCOG0912 trial. The incidence of late complications was compared between the ODG and the LADG arms. In addition, associations between surgery-related factors and the development of late complications were assessed by multivariable analyses using the proportional odds model to identify relevant risk factors.

RESULTS

There was no difference in the type or number of patients with late complications between the LADG and the ODG arms. The multivariable analysis for each late complication revealed that the Billroth-I reconstruction (vs. R-en-Y or Billroth-II) had a lower risk of cholecystitis [odds ratio (OR) 0.187, 95% confidence interval (CI) 0.039-0.905, P = 0.037] or ileus (OR 0.116, 95%CI 0.033-0.406, P < 0.001), and pylorus-preserving gastrectomy (vs. R-en-Y or Billroth-II) had a higher risk of reflux esophagitis (OR 3.348, 95% CI 1.371-8.176, P = 0.008). The surgical approach was not a risk factor for any late complications.

CONCLUSION

Differences in surgical approaches did not constitute a risk for developing late complications after gastrectomy. Billroth-I reconstruction reduced the risk of ileus and cholecystitis, but pylorus-preserving gastrectomy carried a risk for reflux esophagitis.

Five-year follow-up of a randomized clinical trial comparing bursectomy and omentectomy alone for resectable gastric cancer (JCOG1001)

BACKGROUND

Bursectomy, the total resection of the bursa omentalis, is a standard procedure in gastrectomy for resectable gastric cancer. A phase III trial (JCOG1001) comparing bursectomy and omentectomy alone was terminated early at the interim analysis. The final results of the updated analysis after a minimum follow-up of 5 years are reported here.

METHODS

Patients with histologically proven adenocarcinoma of the stomach (cT3-T4a) were randomized (1 : 1) during surgery to bursectomy or omentectomy-alone groups and then underwent D2 gastrectomy. The primary endpoint was overall survival, analysed on an intention-to-treat basis.

RESULTS

A total of 1204 patients (602 bursectomy and 602 omentectomy alone) were enrolled between June 2010 and March 2015. The bursectomy group had a significantly higher incidence of Clavien-Dindo grade III-IV intra-abdominal abscess than the omentectomy-alone group (5.5 versus 2.5 per cent respectively; P = 0.008). The updated 5-year overall survival rates were 74.9 (95 per cent c.i. 71.2 to 78.2) per cent in the bursectomy group and 76.5 (72.8 to 79.7) per cent in the omentectomy-alone group; the adjusted HR for death in the bursectomy group was 1.03 (95 per cent c.i. 0.83 to 1.27) (1-sided P = 0.598). Bursectomy did not decrease peritoneal recurrence (12.1 versus 12.3 per cent respectively; P = 1.000). In a multivariable analysis, old age (above 65 years), tumour located in the lower third or posterior wall of the stomach, macroscopic type 3/5, total gastrectomy, and cT4a were independent predictors of poor overall survival, but omentectomy alone was not.

CONCLUSION

In D2 gastrectomy, bursectomy is not recommended as a standard procedure for cT3-T4a gastric cancer. Registration number: UMIN000003688 (https://www.umin.ac.jp/ctr/).

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.

Protocol digest of a phase III trial to evaluate the efficacy of preoperative chemotherapy with S-1 plus oxaliplatin followed by D2 gastrectomy with postoperative S-1 in locally advanced gastric cancer: Japan Clinical Oncology Group study JCOG1509 (NAGISA Trial)

In Japan, postoperative chemotherapy is a standard care for stage II/III gastric cancer after curative resection with D2 lymph node dissection, and the clinical outcomes of patients with stage III gastric cancer are unsatisfactory. A combination of oral S-1 and oxaliplatin, that is the standard chemotherapy regimen for unresectable advanced/recurrent gastric cancer associated with a high response rate, was considered the most promising preoperative chemotherapy regimen. This randomized phase III trial was started in September 2016 to confirm the superiority of preoperative chemotherapy with S-1 plus oxaliplatin followed by D2 gastrectomy with postoperative chemotherapy compared with D2 gastrectomy with postoperative chemotherapy for patients with clinical T3–4N1–3 M0 locally advanced gastric cancer in terms of overall survival. A total of 470 patients will be enrolled from 63 hospitals in Japan for 8.5 years. This trial has been registered in the Japan Registry of Clinical Trials as jRCTs031180350 [https://jrct.niph.go.jp/latest-detail/jRCTs031180350].

Increasing the class of foundational medication for heart failure is associated with improved prognosis in hospitalized patients with heart failure with reduced or mildly reduced ejection fraction

Aim

To clarify the association between changes in the number of foundational medications for heart failure (FMHF) during hospitalization for worsening heart failure and post-discharge prognosis.

Methods and results

We retrospectively analyzed a combined dataset of three large-scale registries of hospitalized patients with heart failure in Japan (NARA-HF, WET-HF, and REALITY-AHF) and included patients already diagnosed with heart failure with reduced or mildly reduced left ventricular ejection fraction (HFr/mrEF) before admission. Patients were stratified by changes in the number of prescribed FMHF classes, namely angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, beta blockers, and mineralocorticoid receptor blockers, from admission to discharge. The primary endpoint was defined as the combined endpoint of heart failure rehospitalization and all-cause death within 1-year of discharge. The cohort consisted of 1,113 patients, and 482 combined endpoints were observed. In total, 413 (37.1%) patients were on increased FMHF (increased group), 607 (54.5%) remained unchanged (unchanged group), and 93 (8.4%) had a decreased number of FMHF (decreased group) at discharge compared to the time of admission. In multivariable analysis, the increased group was associated with a significantly lower incidence of the primary endpoint compared with the unchanged group (hazard ratio 0.56, 95% confidence interval 0.45–0.60; P&lt;0.001) and decreased group (hazard ratio 0.58, 95% confidence interval 0.40–0.84; P=0.004).

Conclusion

Increasing the number of FMHF cases during heart failure hospitalization is associated with a better prognosis in patients with HFr/mrEF.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): REALITY registry was funded by the Cardiovascular Research Fund of Japan.WET-HF registry was supported by a Grant-in-Aid for Young Scientists (Y.S. JSPS KAKENHI, 18K15860).

Prognostic Impact of Long-term Postoperative Pneumonia in Elderly Patients with Early Gastric Cancer

Background: Elderly patients with stage I gastric cancer, a disease that is curable by surgery, easily develop long-term postoperative pneumonia (LTPP) within two years after surgery despite showing no active symptoms. The present study assessed whether or not LTPP determines the later prognosis among elderly patients.

Methods: We retrospectively examined patients >75 years old who underwent R0 gastrectomy for gastric cancer and were diagnosed with T1 disease at National Cancer Center Hospital between 2005 and 2012. LTPP was evaluated by chest computed tomography every year until two years after surgery.

Results: Of the 3412 patients who underwent gastrectomy in our hospital during this period, 159 were included in this study. The elderly patients who developed LTPP had a worse prognosis than those who did not. Furthermore, their comorbidities and LTPP were significant independent risk factors for a poor prognosis. Patients who developed LTPP had a significantly higher risk of dying due to respiratory disease or cardiovascular disease than those without pneumonia.

Conclusions: LTPP was significantly related to a poor survival and death from respiratory disease. To improve the prognosis, not only nutritional support but also exercise and rehabilitation program may be required for patients who develop LTPP within two years after surgery.

Feasibility and Safety of Oral Nutritional Supplementation with High-Density Liquid Diet After Total Gastrectomy for Gastric Cancer

INTRODUCTION

Patients requiring total gastrectomy for gastric cancer experience a decrease in food intake leading to severe body weight loss after surgery. This loss may be prevented using a high-density liquid diet of high caloric content and minimal volume. This phase II study evaluated the feasibility and safety of a high-density liquid diet (UpLead^®; Terumo Corporation, Tokyo, Japan) after total gastrectomy.

METHODS

UpLead^® (1 pack, 100 mL, 400 kcal/day) was administered after surgery for 28 days. The primary endpoint was the % relative dose intensity of 28 days of UpLead intake^®. The secondary endpoint was % body weight loss at 1 and 3 months after surgery. The sample size was 35 considering expected and threshold values of 80 and 60%, respectively, with a one-sided alpha error of 10% and statistical power of 80%.

RESULTS

Among 35 patients enrolled before surgery between April 2018 and December 2019, 29 patients who could initiate UpLead^® after surgery were analyzed. Seven patients had interrupted UpLead^® intake due to taste intolerance (n = 6) and due to a duodenal stump fistula (n = 1). The remaining 22 patients completed 28 days of UpLead^® intake, including temporary interruption, with no associated adverse events. The median relative dose intensity was 25.8% (95% confidence interval: 20.6-42.0%). The median body weight loss at 1 and 3 months after surgery was 7.2% (range: 3.2-13.9%) and 13.1% (range: 2.5-20.4%), respectively.

CONCLUSIONS

Oral nutritional supplementation with a high-density liquid diet (UpLead^®) was safely administered but was not feasible after total gastrectomy for gastric cancer. Clinical trial registration number UMIN000032291.