Explore the vast range of titles available.

The sixth edition of the Japanese Gastric Cancer Treatment Guidelines was completed in July 2021, incorporating new evidence that emerged after publication of the previous edition. It consists of a text-based “Treatments” part and a “Clinical Questions” part including recommendations and explanations for clinical questions. The treatments parts include a comprehensive description regarding surgery, endoscopic resection and chemotherapy for gastric cancer. The clinical question part is based on the literature search and evaluation by an independent systematic review team. Consequently, not only evidence for each therapeutic recommendation was clearly shown, but it also identified the research fields that require further evaluation to provide appropriate recommendations.

Background Robotic gastrectomy (RG) using the da Vinci Surgical System for gastric cancer was approved for national medical insurance coverage in Japan in April 2018, and its number has been rapidly increasing since then. Aim We reviewed and compared current evidence on RG and conventional laparoscopic gastrectomy (LG) to identify the differences in surgical outcomes. Methods Three independent reviewers systematically reviewed the data collected from a comprehensive literature search by an independent organization, focusing on the following nine endpoints: mortality, morbidity, operative time, estimated blood loss volume, length of postoperative hospital stay, long-term oncologic outcome, quality of life, learning curve, and cost. Results Compared to LG, RG has lower intraoperative blood loss volume, shorter length of hospital stay, and shorter learning curve, but both procedures have similar mortality. Contrarily, its disadvantages include longer procedural time and higher costs. Although the morbidity rate and long-term outcomes are almost comparable, RG showed superior potentials. Currently, the outcomes of RG are considered comparable to or better than LG. Conclusion RG might be applicable to all gastric cancer patients who fulfill the indication of LG at institutions that meet specific criteria and are approved to claim the National Health Insurance costs for the use of the surgical robot in Japan.

BackgroundRobotic gastrectomy (RG) for gastric cancer (GC) has been increasingly performed for a decade; however, evidence for its use as a standard treatment has not yet been established. The present study aimed to determine the safety, feasibility, and effectiveness of RG for GC.MethodsThis multi-institutional, single-arm prospective study, which included 330 patients from 15 institutions, was designed to compare morbidity rate of RG with that of a historical control (conventional laparoscopic gastrectomy, LG). This trial was approved for Advanced Medical Technology (“Senshiniryo”) B. The included patients were operable patients with cStage I/II GC. The primary endpoint was morbidity (Clavien–Dindo Grade ≥ IIIa). The specific hypothesis was that RG could reduce the morbidity rate to less than half of that with LG (6.4%). A sample size of 330 was considered sufficient (one-sided alpha 0.05, power 80%).ResultsAmong the 330 study patients, the protocol treatment was suspended in 4 patients. Thus, 326 patients fully enrolled and completed the study. The median patient age and BMI were 66 years and 22.4 kg/m2, respectively. Distal gastrectomy was performed in 253 (77.6%) patients. The median operative time and estimated blood loss were 313 min and 20 mL, respectively. No 30-day mortality was seen, and morbidity showed a significant reduction to 2.45% with RG (p = 0.0018).ConclusionsRG for cStage I/II GC is safe and feasible. It may be effective in reducing morbidity with LG.

After the initial achievement by Billroth in 1881, surgery for gastric cancer has become increasingly extended. However, it turned out to be limited in Western countries after the publication that denied the role of extended surgery in the 1960s. While surgeons in Japan were still enthusiastic about extended surgery, the Japan Clinical Oncology Group (JCOG) conducted clinical trials to validate the role of extended surgery. Contrary to expectations, the efficacy of extended surgery was not demonstrated. In gastric cancer surgery, postoperative complications were reported to be associated with poor survival. A survival benefit could not be obtained by extended surgery, with high morbidity. Therefore, the paradigm had been changed from extended surgery to minimally invasive surgery (MIS). As an MIS for gastric cancer, laparoscopic surgery has been considered a practical method. Initial laparoscopic gastrectomy (LG) was first performed by Kitano in 1991. Thereafter, LG became increasingly common. Several clinical trials demonstrated the noninferiority of LG to open gastrectomy. LG is now regarded as the standard for cStage I gastric cancer, and the indication is expanding to advanced cancer. However, LG has some drawbacks owing to the restriction of movement caused by straight‐shaped forceps. Robotic gastrectomy (RG) is considered a major breakthrough to circumvent the drawbacks in LG using articulated devices. However, the solid evidence demonstrating the advantage of RG has not been proved yet. The JCOG is now conducting a randomized controlled trial to evaluate the superiority of RG to LG in terms of reducing morbidity.

BackgroundsLaparoscopy-assisted distal gastrectomy (LADG) for gastric cancer is safe and feasible. In contrast, no prospective study evaluating the safety and efficacy of laparoscopy-assisted total gastrectomy (LATG) or laparoscopy-assisted proximal gastrectomy (LAPG) has been completed. We conducted a single-arm confirmatory trial to evaluate the safety of LATG/LAPG for clinical stage I (T1N0/T1N1/T2N0) proximal gastric cancer.MethodsThe extent of lymphadenectomy was selected based on the Japanese Gastric Cancer Treatment Guidelines. The mini-laparotomy incision was required to be ≤ 6 cm. The primary endpoint was the proportion of grade 2–4 (CTCAE ver. 4.0) esophagojejunal anastomotic leakage. The planned sample size was 245 considering a threshold of 8% and one-sided alpha of 2.5%.ResultsBetween April 2015 and February 2017, 244 eligible patients were enrolled. LATG/LAPG was performed in 195/49. The proportion of conversions was 1.7%. Clinical T1N0/T1N1/T2N0 was 212/9/23. The extents of lymphadenectomy were as follows: D1+: 229; D2: 15. The median operation time was 309 min (IQR 265–353). The median blood loss was 30 ml (IQR 10–86). Grade 2–4 esophagojejunal anastomotic leakage was 2.5% (6/244; 95% CI 0.9–5.3). The overall proportion of in-hospital grade 3–4 adverse events was 29% (71/244). The proportions of intraabdominal abscess and pancreatic fistula were 3.7% and 2.0%, respectively. There were no treatment-related deaths.ConclusionsThis trial confirmed the safety of LATG/LAPG. After the non-inferiority of LADG is confirmed in our phase III trial (JCOG0912), LATG/LAPG is expected to be established as one of the standard treatments for clinical stage I gastric cancer.

BackgroundPreoperative malnutrition can worsen morbidity and mortality; however, the role of postgastrectomy nutritional status remains unclear. Our purpose was to clarify whether malnutrition after gastrectomy could predict long-term survival.MethodsPatients with pathological stage I, II, and III gastric cancer who underwent gastrectomy between 2002 and 2013 were included. The nutrition risk index (NRI) was evaluated before and at 1, 3, 6 and 12 months after gastrectomy. The patients were divided into normal (NRI > 97.5) or malnutrition (NRI ≤ 97.5) groups, and we compared the correlations of clinicopathological characteristics, surgical treatment, and overall survival between the two groups.ResultsAmong the 760 participants, patients in the malnutrition group were significantly older and had higher incidences of comorbidity and advanced cancer than the patients in the normal group. Multivariate analysis showed that overall survival was poorer in the malnutrition group before gastrectomy [hazard ratio (HR) 1.68] and at 1 month (HR 1.77), 3 months (HR 2.18), 6 months (HR 1.81) and 12 months (HR 2.17) after gastrectomy (all p < 0.01). Malnutrition at 1 and 3 months after gastrectomy was significantly associated with poor cause-specific survival. Total gastrectomy, preoperative malnutrition, older age, and adjuvant chemotherapy were independent risk factors of postoperative malnutrition at 12 months postgastrectomy.ConclusionsMalnutrition before gastrectomy and at 1, 3, 6 and 12 months after gastrectomy significantly and adversely affects overall survival. Nutritional interventions to lessen the impact of postoperative malnutrition offer hope for prolonged survival.

BackgroundThe prognosis of patients with linitis plastica (type 4) and large (≥ 8 cm) ulcero-invasive-type (type 3) gastric cancer is extremely poor, even after extended surgery and adjuvant chemotherapy. Given the promising results of our previous phase II study evaluating neoadjuvant chemotherapy (NAC) with S-1 plus cisplatin (JCOG0210), we performed a phase III study to confirm the efficacy of NAC in these patients, with the safety and surgical results are presented here.MethodsEligible patients were randomized to gastrectomy plus adjuvant chemotherapy with S-1 (Arm A) or NAC followed by gastrectomy + adjuvant chemotherapy (Arm B). The primary endpoint was the overall survival (OS). This trial is registered at the UMIN Clinical Trials Registry as C000000279.ResultsFrom February 2007 to July 2013, 300 patients were randomized (Arm A 149, Arm B 151). NAC was completed in 133 patients (88%). Major grade 3/4 adverse events during NAC were neutropenia (29.3%), nausea (5.4%), diarrhea (4.8%), and fatigue (2.7%). Gastrectomy was performed in 147 patients (99%) in Arm A and 139 patients (92%) in Arm B. The operation time was significantly shorter in Arm B than in Arm A (median 255 vs. 240 min, respectively; p = 0.024). There were no significant differences in Grade 2–4 morbidity and mortality (25.2% and 1.3% in Arm A and 15.8% and 0.7% in Arm B, respectively).ConclusionsNAC for type 4 and large type 3 gastric cancer followed by D2 gastrectomy can be safely performed without increasing the morbidity or mortality.

This study aimed to establish the Japanese Cancer Genome Atlas (JCGA) using data from fresh frozen tumor tissues obtained from 5143 Japanese cancer patients, including those with colorectal cancer (31.6%), lung cancer (16.5%), gastric cancer (10.8%) and other cancers (41.1%). The results are part of a single‐center study called “High‐tech Omics‐based Patient Evaluation” or “Project HOPE” conducted at the Shizuoka Cancer Center, Japan. All DNA samples and most RNA samples were analyzed using whole‐exome sequencing, cancer gene panel sequencing, fusion gene panel sequencing and microarray gene expression profiling, and the results were annotated using an analysis pipeline termed “Shizuoka Multi‐omics Analysis Protocol” developed in‐house. Somatic driver alterations were identified in 72.2% of samples in 362 genes (average, 2.3 driver events per sample). Actionable information on drugs that is applicable in the current clinical setting was associated with 11.3% of samples. When including those drugs that are used for investigative purposes, actionable information was assigned to 55.0% of samples. Germline analysis revealed pathogenic mutations in hereditary cancer genes in 9.2% of samples, among which 12.2% were confirmed as pathogenic mutations by confirmatory test. Pathogenic mutations associated with non–cancerous hereditary diseases were detected in 0.4% of samples. Tumor mutation burden (TMB) analysis revealed 5.4% of samples as having the hypermutator phenotype (TMB ≥ 20). Clonal hematopoiesis was observed in 8.4% of samples. Thus, the JCGA dataset and the analytical procedures constitute a fundamental resource for genomic medicine for Japanese cancer patients. The present study aims to establish the Japanese Cancer Genome Atlas (JCGA) by analyzing fresh frozen tumor tissues obtained from 5143 Japanese cancer patients. Somatic driver and druggable alterations were detected in 72.2% and 11.3% of samples, respectively, and germline pathogenic mutations in hereditary cancer genes were identified in 9.2% of samples. The JCGA dataset and analytical procedures constitute a fundamental resource for genomic medicine for Japanese cancer patients.

Aim Much attention has been paid to conversion therapy for stage IV gastric cancer, however, its operative comorbidities and survival benefit have not yet been clarified. CONVO‐GC‐1, an international retrospective cohort study, was designed to investigate the role of conversion surgery in Japan, Korea, and China. Methods The rate of operative complications was the primary endpoint and the overall survival (OS), according to the four‐category criteria previously published (Gastric Cancer:19; 2016), was analyzed as the secondary endpoint. Results A total of 1206 patients underwent surgery after chemotherapy with curative intent. Operative complications were observed in 290 (24.0%) patients in all grades, including pancreatic fistula and surgical site infection. The median survival time (MST) of all resected patients was 36.7 mo (M) and those of R0, R1, and R2 resection were 56.6 M, 25.8 M, and 21.7 M, respectively. Moreover, the MST of R0 patients were 47.8 M, 116.7 M, 44.8 M in categories 1, 2, and 3, respectively, and not reached in category 4. Interestingly, the MST of P1 patients was as favorable as that of P0CY1 patients if R0 resection was achieved. The MST of patients with liver metastasis was also favorable regardless of the number of lesions, and the MST of patients with para‐aortic lymph node (LN) No 16a1/b2 metastasis was not inferior to that of patients with para‐aortic LN No 16a2/b1 metastasis. Conclusion Conversion therapy for stage IV gastric cancer is safe and could be a new therapeutic strategy to improve the survival of patients, especially those with R0 resection. R0 resection of conversion therapy can be a new strategy for gastric cancer.