Prognostic factors of conversion surgery for stage IV gastric cancer: A multi-institutional retrospective analysis

Background

Conversion surgery (CS) is a highly anticipated strategy for stage IV advanced gastric cancer (AGC) with a good response to chemotherapy. However, prognostic factors limiting R0 resection remain unclear. In this multi-institutional study, we investigated the clinical outcomes of CS for stage IV AGC and the prognostic factors of CS-limiting R0 resection and analyzed them according to metastatic patterns.

Methods

Clinical data on 210 patients who underwent CS for stage IV AGC at six institutions between 2007 and 2017 were retrospectively retrieved. The patient background, preoperative treatment, operative outcomes, and survival times were recorded. Prognostic factors for overall and recurrence-free survival were investigated using univariate and multivariate analyses for patients who underwent R0 resection.

Results

R0 resection was achieved in 146 (70%) patients. The median survival time was 32 months, and the 3-year survival rate was 45%. Patients who achieved R0 resection had significantly longer survival than those with R1/2 resection (median survival time: 41.5 months vs. 20.7 months). Multivariate analysis identified pathological N positivity for overall and relapse-free survival and pathological T4 for relapse-free survival as significant independent poor prognostic factors of R0 resected patients. There was no significant difference in survival among the peritoneum, liver, and lymph node groups regarding the initial metastatic sites.

Conclusions

CS with R0 resection for patients with stage IV AGC can lead to longer survival. Patients with pathological T4 and pathological N positivity were eligible for intensive adjuvant therapy after CS with R0 resection.

Investigation of the impact of COVID-19 on postoperative outcomes using a nationwide Japanese database of patients undergoing laparoscopic distal gastrectomy and low anterior resection for gastric cancer and rectal cancer

Background

The COVID-19 outbreak made conventional medical care impossible, forcing changes in both healthcare providers and patients. In Japan, COVID-19 infection began spreading in earnest in 2020 and exploded in 2021. There was concern that the medical impact of COVID-19 in 2021 would differ from that in 2020. We aimed to clarify the impact of COVID-19 on mortality and anastomotic leakage in laparoscopic surgery for gastric cancer and rectal cancer in Japan using the National Clinical Database (NCD).

Methods

We collected data from patients who underwent laparoscopic distal gastrectomy (LDG) and laparoscopic low anterior resection (LLAR) from January 2018 to December 2021 from the NCD, a web-based surgical registration system in Japan. The number of surgical cases, monthly incidence of mortality and morbidity (anastomotic leakage), standardized mortality ratio (SMR), and standardized morbidity-leakage ratio (SMLR [ratio of observed patients to expected patients calculated using the risk calculator established in the NCD]) were evaluated.

Results

The numbers of LDG and LLAR cases continued to decline in the first year of the pandemic in 2020 and were as low in 2021 as in 2020. Although the numbers of robot-assisted LDG and LLAR cases increased, the growth rate was lower than the rate of increase prior to the pandemic. Mortality and anastomotic leakage, two of the most important complications, as assessed by SMR and SMLR, did not worsen during the pandemic in comparison to the pre-pandemic period.

Conclusions

Laparoscopic surgeries were performed safely in Japan and were not affected by the COVID-19 pandemic.

Indications for neoadjuvant chemotherapy in older patients undergoing esophagectomy for esophageal cancer

PURPOSE

To investigate the indications for neoadjuvant chemotherapy (NAC) in esophageal cancer patients aged 75 years or older.

METHODS

We analyzed data, retrospectively, from 155 patients over 75 years old, who underwent esophagectomy for esophageal cancer between 2010 and 2020. Forty-one patients underwent upfront surgery (US group) and 114 were treated with NAC followed by surgery (NAC group). We compared the patient backgrounds and perioperative outcomes including prognosis, between the two groups.

RESULTS

The NAC group patients were significantly younger and had significantly more advanced clinical stage disease than the US group patients. The incidence of postoperative complications was similar in the two groups. Patients with a good pathological response to NAC had a significantly better prognosis than those with a poor response and those in the US group. Among patients with a performance status (PS) of 0, the 5-year OS rate was 56.5% in the NAC group and 38.1% in the US group (HR = 0.63, 95% CI 0.35-1.12). Among those with a PS of 1-2, the 5-year OS rates were 28.1% and 57.1%, respectively (HR = 1.69, 95% CI 0.99-2.89; P = 0.037 for interaction).

CONCLUSIONS

NAC did not improve the postoperative prognosis of older esophageal cancer patients with a PS of 1 or higher.

Prognostic factors and significance of postoperative adjuvant chemotherapy in patients with advanced gastric cancer undergoing neoadjuvant chemotherapy followed by gastrectomy

PURPOSE

In Japan, gastrectomy with D2 lymph node dissection and postoperative adjuvant chemotherapy are the standard treatments for locally advanced gastric cancer. Neoadjuvant chemotherapy (NAC) is not affected by postgastrectomy syndromes or postoperative complications. This multicenter retrospective study investigated the prognostic factors and significance of postoperative adjuvant chemotherapy in patients with advanced gastric cancer who underwent NAC followed by gastrectomy.

METHODS

Consecutive patients (n = 221) with advanced gastric cancer who underwent NAC followed by curative surgery were enrolled in this study. Prognostic factors including postoperative adjuvant chemotherapy were investigated using univariate and multivariate analyses.

RESULTS

A multivariate analysis revealed that pathological lymph node metastasis (ypN) status and postoperative adjuvant chemotherapy were independent prognostic factors for the overall and relapse-free survival. Forty-five patients (20.4%) did not receive postoperative adjuvant chemotherapy. There were no significant differences between patients with and without adjuvant chemotherapy for all factors, except age. The most common reason for not undergoing postoperative adjuvant chemotherapy was a poor condition (n = 23).

CONCLUSIONS

ypN status and postoperative adjuvant chemotherapy were independent prognostic factors in gastric cancer patients who underwent NAC followed by curative gastrectomy. It is important to maintain the patient's condition during NAC and the perioperative period so that they can receive postoperative adjuvant chemotherapy.

English version of Japanese Clinical Practice Guidelines 2022 for gastrointestinal stromal tumor (GIST) issued by the Japan Society of Clinical Oncology

The Japan Society of Clinical Oncology Clinical Practice Guidelines 2022 for gastrointestinal stromal tumor (GIST) have been published in accordance with the Minds Manual for Guideline Development 2014 and 2017. A specialized team independent of the working group for the revision performed a systematic review. Since GIST is a rare type of tumor, clinical evidence is not sufficient to answer several clinical and background questions. Thus, in these guidelines, we considered that consensus among the experts who manage GIST, the balance between benefits and harms, patients' wishes, medical economic perspective, etc. are important considerations in addition to the evidence. Although guidelines for the treatment of GIST have also been published by the National Comprehensive Cancer Network (NCCN) and the European Society for Medical Oncology (ESMO), there are some differences between the treatments proposed in those guidelines and the treatments in the present guidelines because of the differences in health insurance systems among countries.

Phase II Study of the Liposomal Formulation of Eribulin (E7389-LF) in Combination with Nivolumab: Results from the Gastric Cancer Cohort

PURPOSE

E7389-LF is a liposomal formulation of the microtubule dynamics inhibitor eribulin and has shown preliminary efficacy in the treatment of gastric cancer. Study 120, a phase Ib/II open-label study, assessed efficacy and safety of E7389-LF in combination with nivolumab, a programmed cell death (PD)-1 inhibitor. This report focuses on the gastric cancer cohort within the expansion phase.

PATIENTS AND METHODS

Eligible patients had unresectable, measurable gastric cancer, progression following a platinum drug plus fluoropyrimidine (1L), and a taxane-containing regimen (2L). The primary objective of the expansion phase was objective response rate, secondary objectives included safety and PFS, and exploratory objectives included overall survival and biomarker evaluation. Patients received E7389-LF 2.1 mg/m2 in combination with nivolumab 360 mg every 3 weeks, both as intravenous infusions. Tumor responses were assessed every 6 weeks by the investigators per RECIST v1.1. Plasma and tumor biomarkers were assessed.

RESULTS

In the 31 patients who received E7389-LF in combination with nivolumab, the objective response rate was 25.8% [confidence interval (CI), 11.9-44.6]. The median progression-free survival was 2.69 months (95% CI, 1.91-2.99) and median overall survival was 7.85 months (95% CI, 4.47-not estimable). The most common treatment-related TEAE of any grade were neutropenia (77.4%), leukopenia (74.2%), and decreased appetite (51.6%). E7389-LF in combination with nivolumab significantly increased CD8-positive cells at C2D1 (P = 0.039), and six of seven vascular markers and four IFNγ-related markers showed increases from C1D1.

CONCLUSIONS

Promising antitumor activity was observed with E7389-LF in combination with nivolumab in patients with gastric cancer, and no new safety signals were observed, compared with either monotherapy.

Development of a new gastrointestinal endoscope forceps plug that can minimize gas leakage

Background and aims

In our previous study, we visualized and systematically evaluated gas leakage from the forceps plug of the gastrointestinal endoscope system using the Schlieren system. In order to minimize the potential risk of infection from gas leakage from the gastrointestinal endoscope, the development of a new forceps plug was considered urgent. In this study, we analyzed the structure of commercially available forceps plugs and attempted to develop new forceps plugs with improvements.

Methods

Microfocus computed tomography was used to nondestructively analyze the structural changes that occur when forceps are inserted into a commercially available forceps plug. Based on the findings, the basic structure of the newly developed forceps plug was set. We examined the airtightness of these newly developed plugs using the Schlieren system and also compared their fractional resistance with those of commercially available plugs.

Results

As a result of the nondestructive analysis, all of the commercially available plugs had a single valve, and the cleavage created in the valve during forceps, insertion was large in the case of plugs with slit-type entrances. In the newly developed forceps plugs, all four types of plugs showed less gas leakage and similar or better usability compared to the commercially available plugs.

Conclusions

The structural weaknesses of the existing gastrointestinal endoscopic forceps plugs were identified. Based on the findings, we froze the design of a prototype of a new forceps plug that was airtight and not inferior in usability compared to commercially available plugs.

Serum NY-ESO-1 antibody as a predictive biomarker for postoperative recurrence of gastric cancer: a multicenter prospective observational study

BACKGROUND

No reliable marker has been identified to predict postoperative recurrence of gastric cancer. We designed a clinical trial to investigate the utility of serum NY-ESO-1 antibody responses as a predictive marker for postoperative recurrence in gastric cancer.

METHODS

A multicenter prospective study was conducted between 2012 and 2021. Patients with resectable cT3-4 gastric cancer were included. Postoperative NY-ESO-1 and p53 antibody responses were serially evaluated every 3 months for 1 year in patients with positive preoperative antibody responses. The recurrence rate was assessed by the positivity of antibody responses at 3 and 12 months postoperatively.

RESULTS

Among 1001 patients, preoperative NY-ESO-1 and p53 antibody responses were positive in 12.6% and 18.1% of patients, respectively. NY-ESO-1 antibody responses became negative postoperatively in non-recurrent patients (negativity rates; 45% and 78% at 3 and 12 months, respectively), but remained positive in recurrent patients (negativity rates; 9% and 8%, respectively). p53 antibody responses remained positive in non-recurrent patients. In multivariate analysis, NY-ESO-1 antibody positivity at 3 months (P  < 0.03) and 12 months (P  < 0.001) were independent prognostic factors for a shorter recurrence-free interval.

CONCLUSIONS

Serum NY-ESO-1 antibodies may be a useful predictive marker for postoperative recurrence in gastric cancer.

CLINICAL TRIAL REGISTRATION

UMIN000007925.

A new scope warmer/cleaner for laparoscopic surgery: a disposable hot pack

BACKGROUND

Fogging and staining of a laparoscope lens negatively impact surgical visualization. We hypothesized that the disposable hot pack could not only warm but also clean laparoscopes. Hence, this study verified and developed the disposable hot pack with anti-fogging and cleaning function.

MATERIAL AND METHODS

The laparoscope was inserted into a swine abdominal cavity for five minutes. Then, the laparoscopic tip was heated with 65 °C saline or the folded disposable hot pack with nonwoven fabric coated surfactant for ten seconds (n = 15). Also, a laparoscopic tip with dirt was wiped with the prototype or conventional gauze for 10 s (n = 10). The dirt, fogging, and temperature of the laparoscopic tip were respectively evaluated after the laparoscope was inserted into the abdominal cavity.

RESULTS

The laparoscopic tip temperature five minutes after insertion into the abdominal cavity was similar (31.1 °C vs 31.2 °C, p = 0.748) and there was no fogging in both methods. The conventional gauze had significantly less temperature of the laparoscopic tip after cleaning and higher fogging occurrence than the prototype (29.5 °C vs 34.0 °C, p < 0.001, 30% vs 0%, p = 0.030, respectively), although there was no dirt left after both methods.

CONCLUSION

The disposable hot pack has a strong potential as an anti-fogging and cleaning device for use during laparoscopic surgery.

Association between fibrosis around the tumor and postoperative infectious complication in patients with esophageal cancer who underwent preoperative therapy

BACKGROUND

Multidisciplinary treatment combining chemotherapy, chemo radiation therapy (CRT), and surgery has been utilized for advanced esophageal cancer. However, preoperative treatment could cause postoperative inflammation and complications. We hypothesized that fibrosis surrounding tumor tissue caused by preoperative treatment could induce postoperative systemic inflammation and influence postoperative complications.

METHODS

Surgical specimens from patients with thoracic esophageal cancer who underwent preoperative CRT (38 cases) or chemotherapy (77 cases) and those who received no preoperative treatment (49 cases) were evaluated to measure the fibrotic area adjacent to the tumor (10 mm from the tumor edge) by applying Azan staining. Pleural effusion and peripheral blood serum interleukin-6 levels were analyzed to evaluate local and systemic postoperative inflammation in 37 patients.

RESULTS

The fibrotic areas around the tumors were significantly larger in patients who underwent preoperative CRT than in patients who underwent chemotherapy (p < 0.001) or who had received no preoperative therapy (p < 0.001). Infectious complications were higher in patients who underwent preoperative CRT than chemotherapy (p = 0.047) or surgery alone (p < 0.001). The patients with larger fibrotic areas had more infectious complications (p = 0.028). Multivariate analysis showed that both a large fibrotic area and preoperative CRT were correlated with infectious complications, but not significantly. Pleural effusion interleukin-6 was significantly higher in patients who underwent preoperative CRT than in patients who received no preoperative therapy (p = 0.013).

CONCLUSIONS

A large fibrotic peritumoral esophageal tissue area after preoperative treatment could cause postoperative inflammatory response and infectious complications.

Use of current automatic smoke evacuation system in flexible gastrointestinal endoscopy: Its feasibility and potential usefulness

Objectives

Flexible endoscopy does not have a system that can automatically evacuate surgical smoke generated in the gastrointestinal lumen. We aimed to investigate the feasibility and potential usefulness of automatic smoke evacuation systems in flexible endoscopy.

Methods

[Bench] After surgical smoke generated in the stomach was evacuated by the evacuator, the degree of residual smoke and gastric luminal collapse were evaluated to optimize the evacuator settings. [Animal] Insufflation, suction, and total operation time to complete the protocol of 10 cauterizations of the gastric mucosa were measured in three groups: "manual suction only," "manual suction with automatic evacuation (50% force)," and "manual suction with automatic evacuation (70% force)." The stability of endoscopic visualization and operability was evaluated by 10 endoscopists blinded to those suction settings, and the number of manual suctions, insufflations, and total operation time were measured.

Results

[Bench] The degree of residual smoke and gastric luminal collapse were inversely correlated. [Animal] When the automatic evacuator was partially used, there was no difference in the insufflation time, but the suction time (vs 50%; p = 0.011, vs. 70%; p = 0.011) and total operation time (vs. 50%; p = 0.012, vs. 70%; p = 0.036) were significantly reduced compared to manual operation only. Furthermore, manual suction with automatic evacuation (50% force) significantly improved the stability of endoscopic visualization and operability compared to manual operation only (p = 0.041, p = 0.0085).

Conclusions

The automatic smoke evacuation in flexible gastrointestinal endoscopy was potentially feasible and useful by improving the device setting.

The role of anterior gastropexy in elderly Japanese hiatal hernia patients

PURPOSE

As Japanese society ages, the number of surgeries performed in elderly patients with hiatal hernia (HH) is increasing. In this study, we examined the feasibility, safety, and potential effectiveness of the addition of anterior gastropexy to hiatoplasty with or without mesh repair and/or fundoplication in elderly Japanese HH patients.

METHODS

We retrospectively evaluated 39 patients who underwent laparoscopic HH repair between 2010 and 2021. We divided them into 2 groups according to age: the "younger" group (< 75 years old, n = 21), and the "older" group (≥ 75 years old, n = 18). The patient characteristics, intraoperative data, and postoperative results were collected.

RESULTS

The median ages were 68 and 82 years old in the younger and older groups, respectively, and the female ratio was similar between the groups (younger vs. older: 67% vs. 78%, p = 0.44). The older group had more type III/IV HH cases than the younger group (19% vs. 83%, p < 0.001). The operation time was longer in the older group than in the younger group, but there was no significant difference in blood loss, perioperative complications, or postoperative length of stay between the groups. The older group had significantly more cases of anterior gastropexy (0% vs. 78%, p < 0.001) and less fundoplication (100% vs. 67%, p = 0.004) than the younger group. There was no significant difference in HH recurrence between the groups (5% vs. 11%, p = 0.46).

CONCLUSIONS

The addition of anterior gastropexy to other procedures is feasible, safe, and potentially effective in elderly Japanese patients with HH.

Long-Term Outcomes of Pylorus-Preserving Gastrectomy for Early Gastric Cancer

BACKGROUND

In the short term, pylorus-preserving gastrectomy (PPG) has been reported to have advantages over distal gastrectomy (DG) with regard to postprandial symptoms and dumping syndrome. We aimed to evaluate the quality of life after PPG for early gastric cancer in the long term in comparison to that after DG.

METHODS

Twenty-six patients who underwent gastrectomy (11 PPG, 15 DG) for early gastric cancer at Osaka University Hospital participated and were followed for more than 4 years. Body weight changes, nutritional status, dual-phase scintigraphy findings, endoscopic survey results, and questionnaire responses after gastrectomy were examined.

RESULTS

There were significantly lower ratios of weight changes in PPG than in DG, 5 years after surgery. There were no differences in the clinicopathological characteristics, nutritional parameters, questionnaire responses, and endoscopic findings between the two groups. Based on gastric scintigraphy, although the gastric emptying of liquids showed similar curves in the two groups, gastric emptying of solids was significantly slower in the PPG group than in the DG group (P = .039).

DISCUSSION

PPG had advantages with regard to long-term outcomes over DG in terms of weight maintenance and the prevention of rapid gastric emptying. PPG might be efficient in patients with early gastric cancer.

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.

Serum NY-ESO-1 and p53 antibodies as useful tumor markers in gastric cancer

Purpose

The NY-ESO-1 antigen is highly immunogenic and often spontaneously induces an immune response in patients with cancer. We conducted a large-scale multicenter cohort study to investigate the utility of serum NY-ESO-1 and p53 antibodies as predictive markers for the postoperative recurrence of gastric cancer. Here, we examined the usefulness of pre-treatment NY-ESO-1 and p53 antibodies as tumor markers for the diagnosis of gastric cancer in combination with carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9).

Methods

A total of 1031 patients with cT3-4 gastric cancer were enrolled in the study. NY-ESO-1 and p53 antibodies were assessed prior to treatment. The positivity of NY-ESO-1 and p53 antibodies, CEA, and CA19-9 was evaluated before treatment.

Results

Serum NY-ESO-1 and p53 antibodies were positive in 12.6% and 18.1% of the patients, respectively. Positive NY-ESO-1 antibody response was correlated with male gender, higher cStage, and upper tumor location. However, a positive p53 antibody response was not associated with tumor factors. The combination of NY-ESO-1 or p53 antibody response with CEA and CA19-9, or the 4-factors, was positive in 45.1%, 49.6%, and 53.8% of patients, respectively. Moreover, the 4-factor combination was able to detect >60% of cStage III-IV diseases, which was 14% higher than that with the combination of CEA and CA19-9.

Conclusion

The combination of NY-ESO-1 and p53 antibody responses to CEA and CA19-9 increases the diagnostic accuracy of gastric cancer. Serum NY-ESO-1 and p53 antibodies may be useful tumor markers for gastric cancer.

The impact of contour maps on estimating the risk of gastrointestinal stromal tumor recurrence: indications for adjuvant therapy: an analysis of the Kinki GIST registry

INTRODUCTION

Contour maps enable risk classification of GIST recurrence in individual patients within 10 postoperative years. Although contour maps have been referred to in Japanese guidelines, their usefulness and role in determining indications for adjuvant therapy is still unclear in Japanese patients. The aims of this study are to investigate the validity of contour maps in Japanese patients with GIST and explore the new strategy for adjuvant therapy.

MATERIALS AND METHODS

A total of 1426 Japanese GIST patients who were registered to the registry by the Kinki GIST Study Group between 2003 and 2012 were analyzed. Patients who had R0 surgery without perioperative therapy were included in this study. The accuracy of contour maps was validated.

RESULTS

Overall, 994 patients have concluded this study. Using contour maps, we validated the patients. The 5-year recurrence-free survival rates of patients within the GIST classification groups of 0-10%, 10-20%, 20-40%, 40-60%, 60-80%, 80-90%, and 90-100% were 98.1%, 96.6%, 92.3%, 48.0%, 37.3%, 41.0% and 42.4%, respectively. We confirmed that this classification by contour maps was well reflected recurrence prediction. Further, in the high-risk group stratified by the modified National Institutes of Health consensus criteria (m-NIHC), the 10-year RFS rate was remarkably changed at a cutoff of 40% (0-40% group vs. 40-100% group: 88.7% vs. 50.3%, p < 0.001).

CONCLUSION

Contour maps are effective in predicting individual recurrence rates. And it may be useful for the decision of individual strategy for high-risk patients combined with m-NIHC.

Innovative device for surgical wound irrigation: a preclinical testing and pilot clinical validation study

INTRODUCTION

Surgical site infection (SSI) poses a substantial postoperative challenge, affecting patient recovery and healthcare costs. While surgical wound irrigation is pivotal in SSI reduction, consensus on the optimal method remains elusive. We developed a novel device for surgical wound irrigation and conducted preclinical and clinical evaluations to evaluate its efficacy and safety.

METHODS

Two preclinical experiments using swine were performed. In the washability test, two contaminated wound model were established, and the cleansing rate between the device and the conventional method were compared. In the contamination test, the irrigation procedure with a fluorescent solution assessed the surrounding contamination of drapes. Subsequently, a clinical trial involving patients undergoing abdominal surgery was conducted.

RESULTS

The washability test demonstrated significantly higher cleansing rates with the device method (86.4% and 82.5%) compared to the conventional method (65.2% and 65.1%) in two contamination models. The contamination test revealed a smaller contaminated region with the device method than the conventional method. In the clinical trial involving 17 abdominal surgery cases, no superficial SSIs or adverse events related to device use were observed.

CONCLUSIONS

Our newly developed device exhibits potential for achieving more effective and safe SSI control compared to conventional wound irrigation.

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).

Phase II study of S-1 plus docetaxel as first-line treatment for older patients with advanced gastric cancer (OGSG 0902)

BACKGROUND

Although there is insufficient evidence for the treatment of older patients with advanced gastric cancer, fluorouracil combined with platinum chemotherapy has been recognized as a standard first-line treatment for such populations in Japan despite the lack of efficacy and toxicity data.

METHODS

Patients aged 75 years or older with advanced gastric cancer were enrolled. S-1 plus docetaxel (docetaxel: 40 mg/m2, day 1; S-1: 80 mg/m2, days 1-14; q21 days) was repeated every 3 weeks. The primary endpoint was overall response rate. Secondary endpoints were safety, progression-free survival, time to treatment failure, and overall survival. The sample size was calculated as 30 under the hypothesis of an expected response rate of 40% and a threshold response rate of 20%, at a power of 90% and a two-sided alpha value of 5%.

RESULTS

From February 2010 to January 2015, 31 patients were enrolled and assessed for efficacy and toxicity. The response rate was 45.2% (95% CI 27.3%-64.0%; p = 0.001) and it exceeded the expected response rate set at 40%. Median progression-free survival was 5.8 months, the 1-year survival rate was 58.1%, and the median survival time was 16.1 months. The major grade 3/4 adverse events were neutropenia (58%), febrile neutropenia (13%), anemia (10%), anorexia (10%), and fatigue (6%).

CONCLUSIONS

These findings indicate that S-1 plus docetaxel as first-line treatment for older patients is feasible and that it has promising efficacy against advanced gastric cancer.

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.

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.

Comparison of the effects of open and laparoscopic approach on body composition in gastrectomy for gastric cancer: A propensity score-matched study

Aim

To compare the effects of open (OG) and laparoscopic gastrectomy (LG) on body composition and muscle strength.

Methods

This study performed a propensity score matching analysis using cases from a large-scale, multicenter, phase III randomized controlled trial concerning oral nutritional supplements after gastrectomy and analyzed both the whole and matched cohorts. Measurements of body composition and hand grip strength (HGS) were performed at baseline (preoperatively) and at 1, 2, 3, 6, and 12 months after gastrectomy.

Results

Of 835 patients, 275 and 560 underwent OG and LG, respectively. Skeletal muscle mass (SMM) and HGS loss were significantly lesser in the LG group than in the OG group. The propensity score-matched analysis, including 120 pairs of patients, confirmed that the % SMM loss values at 1, 2, 3, 6, and 12 POM were -4.5%, -4.0%, -4.7%, -4.6%, and -5.8% in the OG group and -3.0%, -1.9%, -2.4%, -2.2%, and -2.7% in the LG group, respectively. The % SMM loss was significantly lesser in the LG group than in the OG group (repeated measures ANOVA p < 0.001). The HGS loss was non-significantly smaller in the LG group than in the OG group.

Conclusion

Skeletal muscle mass loss was significantly lesser in the LG group than in the OG group in both cohorts, indicating that LG may be more effective than OG for maintaining muscle mass.

Randomized controlled trial of new hemostatic material "sodium calcium alginate" in a preclinical model

BACKGROUND

The demand for nonbiological hemostatic materials has increased in surgical practice; however, few have sufficient hemostatic efficacy. This study investigated whether optimizing the composition of sodium calcium alginate, which forms a stable gel, improves hemostatic efficacy.

METHODS

The sodium calcium alginate was changed for each composition, including powder size, calcium substitution rate, molecular weight, and mannuronic/guluronic acid ratio. The hemostasis in liver punch-out injury and bleeding was evaluated using swine. For the study, sodium calcium alginate with different compositions was randomly applied to bleeding sites. Previous hemostatic materials, including cellulose and sodium alginate, were used as a control. We investigated hemostasis at 2 and 5 minutes after application.

RESULTS

Each powder size (53-150 μm, 150-250 μm, 53-250 μm) had a similar hemostatic effect. However, the hemostatic rate was significantly higher in sodium calcium alginate than in previous hemostatic materials (P value < .01). A 74.1% calcium substitution rate had the highest hemostasis at 2 and 5 minutes after application (2 minutes: 100%, 5 minutes: 95.2%). Regarding molecular weight, the hemostatic rate was significantly higher in 333,000 than in 50,000 (2 minutes: 95% vs 70%, 5 minutes: 95% vs 70%, P = .038). Moreover, a 1.9 mannuronic/guluronic acid ratio had the highest hemostasis compared with the 0.4 mannuronic/guluronic acid ratio (2 minutes: 58.8% vs 11.8%, 5 minutes: 58.8% vs 0%, P = .033) CONCLUSION: The composition of sodium calcium alginate with a high hemostatic effect was optimized. This new hemostatic material demonstrated potential usefulness for bleeding during surgery.

Laparoscopic Gastrectomy for Advanced Gastric Cancer

BACKGROUND

Application of laparoscopic gastrectomy (LG) to advanced gastric cancer is still controversial due to lack of sufficient surgical and oncological outcomes. The purpose of this study was to elucidate the feasibility of LG for advanced gastric cancer by multicenter prospective cohort study.

METHODS

A total of 98 patients with clinical stage II or III gastric cancer from 8 institutes were analyzed in this study. The primary endpoint was incidence of severe postoperative complications of Clavien-Dindo classification grade Ⅲa or higher.

RESULTS

Sixty-six patients underwent laparoscopic distal gastrectomy (LDG), 10 patients laparoscopic proximal gastrectomy (LPG), 21 patients laparoscopic total gastrectomy (LTG), and 1 patient received gastro-jejunostomy. Seven patients had positive lavage cytology (CY1) and R0 rate was 90.8%. Three patients (3.1%) required conversion to open surgery. The incidence of overall postoperative complications and severe postoperative complications were 17.3% and 9.2%, respectively, those were comparable to the data of open surgery for advanced gastric cancer previously published. By surgical procedure, the incidence of severe postoperative complications of LDG, LPG, and LTG were 4.6, 0, and 28.6% and the rate of severe anastomotic leakage of LDG, LPG, and LTG were 0, 0, and 9.5%, respectively. Total gastrectomy was an only independent risk factor of severe postoperative complications in LG for advanced gastric cancer (odds ratio 8.75; 95% confidence interval 1.70-56.69, P = .0092).

DISCUSSION

The incidence of severe postoperative complications after LG performed by qualified surgeons was acceptable even in cases of advanced gastric cancer; however, careful attention is required to adopt LTG. (UMIN000025733).

Accurate Preoperative Evaluation of the Location of Esophagogastric Junction Adenocarcinoma Using Positron Emission Tomography-Computed Tomography

BACKGROUND

The surgical procedure for esophagogastric junction (EGJ) adenocarcinoma usually depends on the location of its epicenter or proximal margin, but accurate evaluation of these positions is often difficult. The usefulness of positron emission tomography-computed tomography (PET-CT) for this purpose is unknown.

METHODS

Between June 2005 and February 2015, we enrolled 30 patients with cT2-4 EGJ adenocarcinoma (Siewert type I/II) who underwent surgical resection. We ascertained the sensitivity and specificity of preoperative PET-CT for identifying the primary tumor and regional lymph node metastasis, and compared PET-CT and pathological findings in terms of the distance from the EGJ to the tumor epicenter or proximal tumor margin.

RESULTS

PET-CT detected the primary tumor with a sensitivity of 97% (29/30), and detected lymph node metastasis with a sensitivity and specificity of 22% (4/18) and 100% (8/8), respectively. No significant association was observed between the maximal standardized uptake value and histological type, tumor size, or pT status. Regarding the accuracy of evaluating tumor location, the median differences between PET-CT and pathological measurements were .6 cm for the tumor epicenter and .5 cm for the proximal margin from the EGJ. PET-CT and pathological findings showed agreement regarding Siewert classification type (I or II) and lengths of esophageal involvement exceeding 4 cm or 2 cm in 77% (10/13), 85% (11/13), and 85% (11/13) of cases, respectively.

DISCUSSION

PET-CT had high sensitivity for primary EGJ adenocarcinoma. It may effectively locate the tumor epicenter and proximal margin and thus help clinicians determine the optimal surgical procedure.

Oral frailty is a risk factor for body weight loss after gastrectomy: a single-center, retrospective study

BACKGROUND

Body weight loss (BWL) is a serious complication of gastrectomy in patients with gastric cancer (GC). Nutritional intervention alone is inadequate for preventing BWL, and a new approach is needed. Oral frailty among older adults has recently attracted attention. This study aimed to investigate masticatory ability and BWL after gastrectomy.

METHODS

This was a single-center, retrospective study. Functional tooth units (FTU) were used to measure masticatory ability. Patients with FTU < 4 were defined as low FTU group and FTU ≥ 4 as high FTU group. The BWL was compared between the two groups.

RESULTS

Sixty patients who underwent distal gastrectomy for GC from March 2022 to January 2023 were enrolled in this study. The median FTU was 3 (range 0-12). The low-FTU group (FTU < 4) included 29 patients, while the high-FTU group (FTU ≥ 4) included 31 patients. The %BWL in the low FTU group was significantly higher than that in the high-FTU group at 1 and 3 months (p = 0.003 and p = 0.017, respectively). The risk factors associated with a %BWL > 5 at 1 and 3 months after gastrectomy were analyzed using logistic regression analysis. Only FTU < 4 was an independent risk factor after gastrectomy for GC in univariate and multivariate analyses (p = 0.028 and p = 0.006, respectively).

CONCLUSIONS

Low FTU in patients with preoperative GC was a risk factor for %BWL 1 and 3 months postoperatively. Appropriate oral interventions may be useful in improving the postoperative nutritional status after gastrectomy.

A case of Barrett's esophageal adenocarcinoma and severe scoliosis with successful salvage esophagectomy after definitive chemoradiotherapy

BACKGROUND

Severe scoliosis can cause reflux esophagitis, and is a risk factor for Barrett's adenocarcinoma of the esophagus. Severe scoliosis is associated with respiratory dysfunction, impaired operative tolerance, and anatomical difficulty in surgical manipulation, and is, therefore, considered a high surgical risk. In this report, we describe the case of a young patient with Barrett's esophageal adenocarcinoma with severe scoliosis who underwent salvage surgery after radical chemoradiotherapy.

CASE PRESENTATION

The patient was a 39-year-old male. Although he had severe scoliosis and paraplegia of both lower limbs since childhood, he was independent in activities of daily living. His previous doctor, who diagnosed the esophageal cancer, determined that surgery was not indicated due to the coexistence of severe scoliosis, so he underwent chemoradiotherapy with curative intent. After chemoradiotherapy, the patient was referred to our hospital for a second opinion because of a tumor remnant. After various additional examinations, thoracoscopic and laparoscopic subtotal esophagectomy for esophageal cancer was performed, along with ante-thoracic route reconstruction using a narrow gastric tube. Although the patient had symptoms associated with postoperative reflux, he recovered well overall and was discharged home about 4 weeks after surgery.

CONCLUSIONS

We report the case of an esophageal cancer patient with severe scoliosis at high surgical risk who underwent successful minimally invasive esophagectomy.

Neoadjuvant chemotherapy for locally advanced gastric cancer in Japan: Consensus meeting at the 77th general meeting of the Japanese Society of Gastroenterological Surgery

Treatment strategy for locally advanced gastric cancer differs worldwide. Neoadjuvant chemotherapy (NAC) is considered one of the promising treatment options for locally advanced gastric cancer, even in Japan, and clinical trials have been conducted or are ongoing. A consensus meeting was organized at the 77th general meeting of the Japanese Society of Gastroenterological Surgery in 2022, in which the current status and future prospects of NAC for locally advanced gastric cancer were discussed. Participants at the meeting looked forward to the results of the JCOG1509 trial, providing solid evidence regarding NAC. The optimal indications and regimens for NAC were also debated. Patients with cStage III gastric cancer are the main targets of NAC in Japan, and a doublet regimen of S-1 and oxaliplatin was preferred by the participants. However, the feasibility of a triplet regimen with S-1, oxaliplatin, and docetaxel, and that with 5-FU, leucovorin, oxaliplatin, and docetaxel has been demonstrated, and these could become treatment options in Japan. Other points of discussion include perioperative chemotherapy to avoid peritoneal recurrence and for patients with dMMR/MSI-high tumors. The panel regarded NAC as a promising treatment option, and NAC will become the standard treatment for cStage III gastric cancer in Japan if an ongoing clinical trial successfully demonstrates its efficacy.

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.

Re-appraisal of the universal definition of tumor rupture among patients with high-risk gastrointestinal stromal tumors

Aim

Tumor rupture has been indicated as a risk factor for recurrence of gastrointestinal stromal tumors (GISTs). The universal definition of tumor rupture was proposed. This study evaluated whether the universal definition was more accurate in identification of GISTs with high recurrent risk than subjective judgment.

Methods

The study included 507 patients with high-risk GISTs who underwent complete resection between December 2012 and December 2015. We conducted a questionnaire survey in participating institutes to re-diagnose tumor rupture based on the universal definition according to their surgical and pathological findings. We compared the clinical outcomes of tumor rupture based on the definition to those based on the surgeon's judgment and clarified the clinical importance of the rupture.

Results

Sixty-four patients were initially registered to have tumor rupture by surgeon's judgment, and it became 90 patients who had tumor rupture after reevaluation. Although there were significant differences in recurrence-free survival (RFS) between no rupture and rupture for both initial registration and reevaluation (p = 0.002, <0.001, respectively), a significant difference in overall survival was only observed after reevaluation (p = 0.011). Tumor rupture was significantly associated with large tumor size, mixed cell type in histology, R1 resection, frequent adjuvant therapy and recurrence, but not with location, mitosis, and genotype. Adjuvant therapy more than 3 years improved RFS of patients with tumor rupture.

Conclusion

This study suggested that tumor rupture based on the universal definition more accurately identified GISTs with poor prognostic outcomes than the subjective judgment.

Association between circ_0004365 and cisplatin resistance in esophageal squamous cell carcinoma

Cisplatin is one of the most predominant drugs for the chemotherapy of esophageal squamous cell carcinoma (ESCC); however, the underlying resistance mechanisms are still almost unknown. The present study performed RNA sequencing of human circular RNA (circRNA) in TE11 cells and cisplatin-resistant TE11 cells (TE11R). The expression profiles determined using CIRCexplorer2 revealed that the expression of circ_0004365, mapped on the Semaphorin 3C gene, was significantly greater in TE11R compared with in TE11. In reverse transcription-quantitative PCR, circ_0004365 expression was observed in human ESCC and non-tumor tissues and was significantly upregulated in ESCC tumor tissues after chemotherapy. Circ_0004365 expression was significantly upregulated in patients with poor pathological response (P=0.02). Furthermore, patients with advanced pT stage showed an upregulation in circ_0004365 expression after chemotherapy (P=0.02). The MTT assay revealed that knockdown of circ_0003465 in TE11 significantly decreased resistance to cisplatin. In conclusion, the present study suggested that circ_0004365 was associated with cisplatin resistance in ESCC and can be used as both a novel biomarker and a therapeutic target.

Surgery for multiple gastric gastrointestinal stromal tumors and large esophageal diverticulum related to germline mutation of the KIT gene: a case report

BACKGROUND

Familial gastrointestinal stromal tumors (GISTs) are mesenchymal tumors of the digestive tract caused by germline gain-of-function mutations in the KIT gene or platelet-derived growth factor receptor alpha gene (PDGFRA). These mutations cause not only multiple GISTs but also diffuse hyperplasia of interstitial cells of Cajal (ICCs), which is related to esophageal motility disorder.

CASE PRESENTATION

A 53-year-old man was referred to our hospital because of anemia and dysphagia. Fifteen years earlier, he had undergone a laparoscopic partial gastrectomy for multiple gastric GISTs with a germline mutation in exon 17 of the KIT gene. An upper gastrointestinal endoscopy revealed that the patient had multiple gastric GISTs and a large esophageal diverticulum directly above the esophagogastric junction. The largest gastric tumor was 7 cm, with a delle that might cause bleeding. Because the patient presented with dysphagia, we performed video-assisted thoracic esophagectomy and laparoscopic-assisted proximal gastrectomy simultaneously. The patient had survived without metastasis for 4 years after surgery and dysphagia had improved.

CONCLUSIONS

This is the first report of successful laparoscopic-thoracoscopic surgery for a patient with familial gastric GISTs accompanied with a large esophageal diverticulum.

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.

Impact of MRI on the post-therapeutic diagnosis of T4 esophageal cancer

BACKGROUND

Opportunities for T4b esophageal cancer patients to receive curative surgery are increasing with the development of multidisciplinary treatments. However, the best modality to accurately diagnose infiltration to the organs surrounding T4b esophageal cancer is still unknown. The aim of this study was to determine the performance of CT and MRI in diagnosing T stage in T4b esophageal cancer, with reference to the pathological diagnosis.

METHODS

A retrospective medical records review of patients with T4b esophageal cancer patients from January 2017 to December 2021 was conducted. Among 125 patients who were treated for cT4b esophageal cancer in Osaka University Hospital, 30 patients were diagnosed with cT4b esophageal cancer by CT, ycT staging with CT (contrast-enhanced images) and MRI (T2-FSE images), and curative R0 resection was performed. Preoperative MRI staging was independently performed by two experienced radiologists. The diagnostic performance of CT and MRI were examined using McNemar's test.

RESULTS

Nineteen and 12 patients were diagnosed with ycT4b by CT and MRI, respectively. Combined T4b organ resection was performed in 15 patients. A pathological diagnosis of ypT4b was made in 11 cases. In comparison to CT, MRI showed a higher diagnostic performance, specificity (47% vs. 89%, p = 0.013), and accuracy (60% vs. 90%, p = 0.015) for CT vs. MRI.

CONCLUSIONS

Our results-with reference to the pathological diagnosis-revealed that MRI had a superior diagnostic performance to CT for diagnosing T4b esophageal cancer invading the surrounding organs. An accurate diagnosis of T4b esophageal cancer may facilitate the implementation of appropriate treatment strategies.

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

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

Long-term outcomes of a phase II study of neoadjuvant imatinib in large gastrointestinal stromal tumors of the stomach

BACKGROUND

Neoadjuvant treatment is recommended for large GISTs due to their friability and risk of extensive operations; however, studies on the indications and long-term results of this approach are lacking.

METHODS

Patients with large (≥ 10 cm) gastric GISTs were enrolled from multiple centers in Korea and Japan after a pathologic confirmation of c-KIT ( +) GISTs. Imatinib (400 mg/d) was given for 6-9 months preoperatively, and R0 resection was intended. Postoperative imatinib was given for at least 12 months and recommended for 3 years.

RESULTS

A total of 56 patients were enrolled in this study, with 53 patients receiving imatinib treatment at least once and 48 patients undergoing R0 resection. The 5-year overall survival and progression-free survival rates were 94.3% and 61.6%, respectively. Even patients with stable disease by RECIST criteria responded well to preoperative imatinib treatment and could undergo R0 resection, with most being evaluated as partial response by CHOI criteria. The optimal reduction in tumor size was achieved with preoperative imatinib treatment for 24 weeks or more. No resumption of imatinib treatment was identified as an independent prognostic factor for recurrence after R0 resection. No additional size criteria for a higher risk of recurrence were identified in this cohort with a size of 10 cm or more.

CONCLUSIONS

Neoadjuvant imatinib treatment is an effective treatment option for gastric GISTs 10 cm or larger. Postoperative imatinib treatment is recommended even after R0 resection to minimize recurrence.

Phase I dose-escalation study on irinotecan, cisplatin, and S-1 combination in chemotherapy-naïve patients with HER2-negative advanced gastric cancer (HERBIS-4B, OGSG 1106)

BACKGROUND

The development of triplet regimens for advanced gastric cancer is challenging. The aim of this phase I dose-escalation study was to determine the maximum tolerated dose and recommended dose of the combination of irinotecan, cisplatin, and S-1 in chemotherapy-naïve patients with HER2-negative advanced gastric cancer.

METHODS

The 3 + 3 design was adopted. Every 4 weeks, patients received an escalating dose of intravenous irinotecan (100-150 mg/m2) on day 1 and fixed doses of intravenous cisplatin (60 mg/m2) on day 1 and oral S-1 (80 mg/m2) on days 1 to 14.

RESULTS

Twelve patients were enrolled in two dose level cohorts. In the level 1 cohort (irinotecan 100 mg/m2, cisplatin 60 mg/m2, and S-1 80 mg/m2), dose-limiting toxicity including grade 4 neutropenia and febrile neutropenia occurred in one of six patients, whereas in the level 2 cohort (irinotecan 125 mg/m2, cisplatin 60 mg/m2, and S-1 80 mg/m2), dose-limiting toxicities including grade 4 neutropenia developed in two of six patients. Thus, the level 1 and 2 doses were determined to be the recommended and maximum tolerated doses, respectively. Common grade 3 or higher adverse events were neutropenia (75%; n = 9), anemia (25%; n = 3), anorexia (8%; n = 1), and febrile neutropenia (17%; n = 2). Irinotecan, cisplatin, and S-1 combination therapy achieved an overall response rate of 67% with a median progression-free survival and overall survival of 19.3 and 22.4 months, respectively.

CONCLUSIONS

The potential treatment efficacy of this triplet regimen in HER2-negative advanced gastric cancer warrants further evaluation, especially in patients requiring intensive chemotherapy.

Effect of the number of cycles of docetaxel + S-1 therapy on long-term survival in adjuvant chemotherapy for stage III gastric cancer. A pooled analysis of the OGSG0604 and OGSG1002 trials

BACKGROUND

S-1 plus docetaxel (DS) therapy followed by S-1 is the standard of care in Japan in postoperative adjuvant chemotherapy for stage III gastric cancer, but long-term survival and the number of DS cycles required are unclear. The purpose of this study was to investigate the impact of the number of cycles of DS therapy on the 5-year survival in stage III gastric cancer in a pooled analysis of two phase II trials (OGSG0604 and OGSG1002).

PATIENTS AND METHODS

Patients with histologically confirmed stage III gastric cancer who underwent gastrectomy with D2 lymphadenectomy were enrolled in this pooled analysis. They received DS therapy for four or eight cycles, followed by S-1 until 1 year postgastrectomy. The 5-year overall survival (OS) and the 5-year disease free survival (DFS) by the landmark analysis was evaluated.

RESULTS

In total, 113 patients from the OGSG0604 and OGSG1002 trials were enrolled in this study. The landmark analysis showed a 5-year OS that was better with four to eight cycles of DS therapy than with one to three cycles of DS therapy, with the best 5-year OS of 77.4% (95% confidence interval, 66.5-90.1%) for eight cycles. The 5-year DFS was approximately 66% when four or eight cycles of DS therapy were given.

CONCLUSION

Although eight cycles of DS therapy may prolong prognosis, the present study did not provide a clear conclusion as to how many DS therapy cycles are needed to improve prognosis after D2 gastrectomy for stage III gastric cancer.

TRIAL REGISTRATION

Registration number: UMIN00000714 and UMIN000004440.

Long-term survival and prognostic factors associated with curative conversion surgery for ct4b esophageal squamous cell carcinoma: Analysis of 200 consecutive cases

BACKGROUND

The optimal treatment strategy for cT4b esophageal cancer has not been established yet. Although curative surgery is sometimes performed after induction treatments, the prognostic factor of cT4b esophageal cancer cases who underwent R0 resection remains unknown.

METHODS

A total of 200 patients with cT4b esophageal cancer who underwent R0 resection after induction treatments between 2001 and 2020 in our institute were included in the present study. The relationship between clinicopathological factors and patient survival is evaluated to identify useful prognostic factors.

RESULTS

The median and 2-year overall survival were 40.1 months and 62.8%, respectively. Disease recurrence occurred in 98 (49%) patients after surgery. Compared to induction chemotherapy alone, chemoradiation-based induction treatments were associated with decreased locoregional recurrence (34.0% vs 60.8%, P = .0077) but increased pulmonary metastases (27.7% vs 9.8%, P = .0210) and dissemination (19.1% vs 3.9%, P = .0139) after surgery. Multivariate analysis of overall survival identified the preoperative C-reactive protein/albumin ratio (hazard ratio 1.7957, P = .0031), response to induction treatments (hazard ratio 2.9663, P = .0009), postoperative pneumonia (hazard ratio 2.3784, P = .0010), and pN (2-3) (hazard ratio 1.5693, P = .0355) as independent prognostic factors. Preoperative C-reactive protein/albumin ratio (hazard ratio 1.6760, P = .0068) and postoperative pneumonia (hazard ratio 1.8365, P = .0200) were also independent prognostic factors for recurrence-free survival.

CONCLUSION

Curative surgery after induction therapy for cT4b esophageal cancer achieved favorable survival. Preoperative C-reactive protein/albumin ratio, postoperative pneumonia, response to induction treatments, and pN were useful prognostic factors.

Essential updates 2021/2022: Perioperative and surgical treatments for gastric and esophagogastric junction cancer

In recent years, important clinical trials for gastric cancer (GC) and esophagogastric junction cancer (EGJC) have been reported, changing the strategies of surgical and perioperative treatment. Although laparoscopic gastrectomy has already been shown to be effective for early-stage cancer, recent evidence from both Asia (JLSSG0901, CLASS-01 and KLASS-02) and Europe (LOGICA and STOMACH trials) has demonstrated that it is useful for advanced GC. Robotic surgery has been rapidly gaining popularity in recent years, and randomized controlled trials are ongoing to evaluate its efficacy. A prospective nationwide multicenter study mapped sites with frequent metastasis and revealed lymphatic flow specific to EGJC, thus establishing the optimal lymph node dissection area and surgical approach based on esophageal involvement. Perioperative chemotherapy, the mainstay of treatment in Europe, also has been established in Asia by the PRODIGY and RESOLVE studies. New clinical trials have been conducted to evaluate the efficacy of combining immunotherapy or molecular-targeted therapy with perioperative chemotherapy or chemoradiotherapy. In this review, we present important recent clinical trials regarding the treatment of GC and EGJC published in 2021 or 2022.

Clinical Significance of Intramural Metastasis as an Independent Prognostic Factor in Esophageal Squamous Cell Carcinoma

BACKGROUND

Although intramural metastasis (IM) in esophageal cancer is considered a poor prognostic factor, there are only limited reports detailing its clinicopathologic characteristics and prognostic impact.

PATIENTS AND METHODS

We retrospectively included patients with esophageal squamous cell carcinoma (ESCC) with esophagectomy at our institution between 2010 and 2016. We compared patients with intramural metastases (IMs) (IM group) versus those without IMs (non-IM group) to clarify the clinical significance of intramural metastasis in ESCC.

RESULTS

A total of 23 (3.9%) out of all 597 patients were identified to have IM. The IMs were located on the cranial side in 13 (56.5%) and caudal side in 10 (43.5%) of the primary tumor, with two multiple cases. The IM group, compared with the non-IM group, was associated with higher percentage of cN-positive (91.3 versus 67.9%, P = 0.02), pN-positive (82.6 versus 55.9%, P = 0.04), and pM(lym)-positive (30.4 versus 12.5%, P = 0.02) cases. Five-year recurrence-free survival (RFS) was significantly worse in the IM group than the non-IM group (14.9 versus 55.0 %, P < 0.001). Multivariable analysis of recurrence-free survival identified pT (HR 1.74, 95% CI 1.36-2.23, P < 0.001), pN (HR 2.11, 95% CI 1.60-2.78, P < 0.001), histological classification (HR 1.68, 95% CI 1.21-2.35, P = 0.002), and pM(LYM) (HR 1.64, 95% CI 1.64-2.95, P < 0.001), along with presence of IM (HR 2.24, 95% CI 1.37-3.64, P < 0.001) to be independent prognostic factors. Lymphatic (65.2 versus 24.9%, P < 0.001) and hepatic (26.1 versus 6.8%, P = 0.005) recurrences were significantly more common in the IM group than in the non-IM group.

CONCLUSIONS

IM was shown to be associated with dismal survival after surgery. A treatment strategy emphasizing more intensive systemic control should be considered for patients with ESCC with IM.

Management of abdominal gas leakage from surgical trocars in laparoscopic surgery: a preclinical study

Introduction: There is an ongoing concern about the potential infectious risk due to pneumoperitoneal gas leakage from surgical trocars in laparoscopic surgery. We aimed to visually confirm the presence of leakage from trocars and investigate the changes in the leakage scale according to intra-abdominal pressures and trocar types. Material and methods: We established a porcine pneumoperitoneum model and performed experimental forceps manipulation using 5-mm grasping forceps with 12-mm trocars. The gas leakage, if any, was imaged using a Schlieren optical system, which can visualize minute gas flow invisible to the naked eye. For measuring the scale, we calculated the gas leakage velocity and area using image analysis software. Four types of unused and exhausted disposable trocars were compared. Results: Gas leakage was observed from trocars during forceps insertion and removal. Both the gas leakage velocity and area increased as the intra-abdominal pressure increased. Every type of trocar we handled was associated with gas leakage, and exhausted disposable trocars had the largest scale gas leakage. Conclusions: We confirmed gas leakage from trocars during device traffic. The scale of leakage increased with high intra-abdominal pressure and with the use of exhausted trocars. Current protection against gas leakage may not be sufficient and new surgical safety measures and device development may be needed in the future.

The clinical impact of COVID-19 on endoscopic surgery in Japan: Analysis of data from the National Clinical Database

Aim

This study aimed to evaluate the impact of the coronavirus disease (COVID-19) pandemic on elective endoscopic surgeries in Japan using the National Clinical Database.

Methods

We retrospectively analyzed the clinicopathological factors and surgical outcomes of laparoscopic cholecystectomy (LC), laparoscopic distal gastrectomy (LDG), and laparoscopic low anterior resection (LLAR) and compared the monthly numbers of each procedure performed in 2020 with those in 2018 and 2019. The degree of infection in prefectures was classified into low and high groups.

Results

In 2020, the number of LCs (except for acute cholecystitis) was 76 079 (93.0% of that in 2019), the number of LDGs was 14 271 (85.9% of that in 2019), and the number of LLARs was 19 570 (88.1% of that in 2019). Although the number of robot-assisted LDG and LLAR cases increased in 2020, the growth rate was mild compared with that in 2019. There was little difference in the number of cases in the degree of infection in the prefectures. The numbers of LC, LDG, and LLAR cases decreased from May to June and recovered gradually. In late 2020, the proportion of T4 and N2 cases of gastric cancer and the number of T4 cases of rectal cancer increased compared with those in 2019. There was little difference between the proportions of postoperative complications and mortality in the three procedures between 2019 and 2020.

Conclusion

The number of endoscopic surgeries decreased in 2020 as a result of the COVID-19 pandemic. However, the procedures were performed safely in Japan.

Initial Evaluation of [18F]FAPI-74 PET for Various Histopathologically Confirmed Cancers and Benign Lesions

The ¹⁸F-labeled fibroblast activation protein inhibitor (FAPI) [¹⁸F]FAPI-74 has the benefit of a higher synthetic yield and better image resolution than ⁶⁸Ga-labeled FAPI. We preliminarily evaluated the diagnostic performance of [¹⁸F]FAPI-74 PET in patients with various histopathologically confirmed cancers or suspected malignancies. Methods: We enrolled 31 patients (17 men and 14 women) with lung cancer (n = 7), breast cancer (n = 5), gastric cancer (n = 5), pancreatic cancer (n = 3), other cancers (n = 5), and benign tumors (n = 6). Twenty-seven of the 31 patients were treatment-naïve or preoperative, whereas recurrence was suspected in the remaining 4 patients. Histopathologic confirmation was obtained for the primary lesions of 29 of the 31 patients. In the remaining 2 patients, the final diagnosis was based on the clinical course. [¹⁸F]FAPI-74 PET scanning was performed 60 min after the intravenous injection of [¹⁸F]FAPI-74 (240 ± 31 MBq). The [¹⁸F]FAPI-74 PET images were compared between the primary or local recurrent lesions of malignant tumors (n = 21) and nonmalignant lesions (n = 8: type-B1 thymomas, granuloma, solitary fibrous tumor, and postoperative or posttherapeutic changes). The uptake and number of detected lesions on [¹⁸F]FAPI-74 PET were also compared with those on [¹⁸F]FDG PET for available patients (n = 19). Results: [¹⁸F]FAPI-74 PET showed higher uptake in primary lesions of various cancers than in nonmalignant lesions (median SUV_max, 9.39 [range, 1.83-25.28] vs. 3.49 [range, 2.21-15.58]; P = 0.053), but some of the nonmalignant lesions showed high uptake. [¹⁸F]FAPI-74 PET also showed significantly higher uptake than [¹⁸F]FDG PET (median SUV_max, 9.44 [range, 2.50-25.28] vs. 5.45 [range, 1.22-15.06] in primary lesions [P = 0.010], 8.86 [range, 3.51-23.33] vs. 3.84 [range, 1.01-9.75] in lymph node metastases [P = 0.002], and 6.39 [range, 0.55-12.78] vs. 1.88 [range, 0.73-8.35] in other metastases [P = 0.046], respectively). In 6 patients, [¹⁸F]FAPI-74 PET detected more metastatic lesions than [¹⁸F]FDG PET. Conclusion: [¹⁸F]FAPI-74 PET showed higher uptake and detection rates in primary and metastatic lesions than did [¹⁸F]FDG PET. [¹⁸F]FAPI-74 PET is a promising novel diagnostic modality for various tumors, especially for precise staging before treatment, including characterization of tumor lesions before surgery. Moreover, ¹⁸F-labeled FAPI ligand might serve a higher demand in clinical care in the future.

Nano-particulate Toll-like Receptor 9 Agonist Potentiates the Antitumor Activity of Anti-Glypican-1 Antibody

BACKGROUND/AIM

Monoclonal antibodies (mAbs) that target tumor antigens have recently been developed. Their antitumor activity is mainly achieved through antibody-dependent cellular cytotoxicity (ADCC) via effector cells such as tumor-infiltrated macrophages and natural killer (NK) cells. CpG oligodeoxynucleotides (ODNs) have potent antitumor activity and are considered to increase the tumor infiltration of macrophages and NK cells; however, a completely solubilized novel CpG-schizophyllan (SPG) complex, K3-SPG, displays more potent antitumor activity. We recently reported the significant antitumor activity of anti-glypican-1 (GPC1) mAb against GPC1-positive esophageal squamous cell carcinoma (ESCC) via ADCC. The aim of this study was to evaluate the potential synergistic antitumor activity of anti-GPC1 mAb and K3-SPG and elucidate the underlying mechanisms using a xenograft model of GPC1-positive human ESCC cells.

MATERIALS AND METHODS

The established human esophageal cancer cell line TE14 was subcutaneously injected into SCID mice. Xenograft mice were treated with anti-GPC1 mAb, K3-SPG, or their combination. Antitumor activity was evaluated by measuring the tumor volume. For FACS analysis, agents were administrated, and tumors were resected 1 day after the final treatment.

RESULTS

Anti-GPC1 mAb or K3-SPG monotherapy showed dose-dependent antitumor activity, and combination therapy with anti-GPC1 mAb and K3-SPG showed antitumor activity (p=0.0859). Flow cytometry revealed significantly increased numbers of macrophages (p=0.0133) and of the ratio of activated NK cells/total NK cells (p=0.0058) following K3-SPG or combination therapy.

CONCLUSION

Combination therapy with K3-SPG and anti-GPC1 mAb or another antitumor mAb may represent a new cancer treatment option acting via ADCC.

Density and maturity of peritumoral tertiary lymphoid structures in oesophageal squamous cell carcinoma predicts patient survival and response to immune checkpoint inhibitors

BACKGROUND

Tertiary lymphoid structures (TLSs) are ectopic lymphoid aggregates in non-lymphoid tissues, which are associated with improved prognosis in some cancer types. This study aimed to investigate the clinical significance of TLSs in oesophageal cancer (EC).

METHODS

In a series of 316 EC surgical specimens from two different institutes, we evaluated the density and maturity of peritumoral TLSs using haematoxylin/eosin, immunohistochemistry, and multiplex immunofluorescence staining. We analysed the association between TLSs and clinicopathological parameters. The clinical significance of TLSs was further evaluated in a different cohort of 34 patients with recurrent EC treated with anti-PD-1 antibody.

RESULTS

Tumours with high TLS density predominantly consisted of matured TLSs. High TLS density was significantly associated with less advanced tumour stage, absence of lymphatic/vascular invasion, better serum nutrition parameters (neutrophils count, albumin, neutrophil-to-lymphocyte ratio, and prognostic nutritional index), and prolonged survival. This survival trend was more remarkable in cases with matured TLSs, which represented an increased population of CD138+ plasma cells. In the second EC cohort, TLS density predicted the clinical response to anti-PD-1 antibody and patient survival.

CONCLUSION

The density and maturity of peritumoral TLSs are useful parameters for predicting long-term survival and response to anti-PD-1 antibody treatment in EC patients.

Long-term response to pimitespib in postoperative recurrent gastrointestinal stromal tumors with PDGFRA D842V mutation: a case report

BACKGROUND

Exon 18 D842V, which is a point mutation from aspartic acid to valine at codon 842, is the most frequent mutation in Platelet-Derived Growth Factor Receptor alpha (PDGFRA)-mutated gastrointestinal stromal tumor (GIST). In the Japanese GIST guidelines, no standard systematic therapy is available for this type of GIST, which is refractory after recurrence. Recently, pimitespib (PIMI), a novel heat shock protein 90 (HSP90) inhibitor, was approved for the treatment of advanced GIST in a phase III study. This report presents a case of a long-term response to PIMI in GIST with PDGFRA D842V mutation.

CASE PRESENTATION

A 55-year-old woman was diagnosed with primary GIST of the stomach and underwent partial gastrectomy. Eight years after the operation, recurrent GISTs were identified as multiple recurrent peritoneal GISTs in the upper right abdomen and pelvic cavity. We administered tyrosine kinase inhibitors, but they achieved poor effects. After failure of the standard treatment, PIMI was administered and achieved a partial response in the patient. The highest reduction rate was 32.7%. After PIMI failed, we performed multiplex gene panel testing, which revealed the PDGFRA D842V mutation.

CONCLUSIONS

We report the first case of long-term response to PIMI in PDGFRA D842V mutant GIST. Pimitespib may be effective for treating GIST harboring this mutation by inhibiting HSP90.