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.

Ovarian serous borderline tumors with recurrent or extraovarian lesions: a Japanese, retrospective, multi-institutional, population-based study

BACKGROUND

Ovarian serous borderline tumors (SBT) are typically unilateral and are primarily treated using hysterectomy and bilateral salpingooophorectomy (SO). However, most young patients prefer fertility-sparing surgeries (FSS) with tumorectomy or unilateral SO. Micropapillary morphology and invasive implants have been designated as histopathological risk indicators for recurrence or metastasis, but their clinical impact remains controversial because of limitations like diagnostic inconsistency and incomplete surgical staging.

METHODS

A nationwide multi-institutional population-based retrospective surveillance was conducted with a thorough central pathology review to reveal the clinical features of SBT. Of 313 SBT patients enrolled in the Japanese Society of Clinical Oncology's Surveillance of Gynecologic Rare Tumors, 289 patient records were reviewed for clinical outcomes. The glass slides of patients at stage II-IV or with recurrence or death were re-evaluated by three gynecological pathologists.

RESULT

The 10-year overall and progression-free survival (PFS) rates were 98.6% and 92.3%. The median recurrence period was 40 months and 77.0% was observed in the contralateral ovary within 60 months. Patients aged ≤ 35 years underwent FSS more frequently and relapsed more (p < .001). A clinic-pathological analysis revealed diagnosis during pregnancy, FSS, and treatment at non-university institutes as well as advanced stage and large diameter were independent risk factors of recurrence. Among patients having pathologically confirmed SBTs, PFS was not influenced by the presence of micropapillary pattern or invasive implants.

CONCLUSION

The recurrence rate was lower in this cohort than previous reports, but the clinical impacts of incomplete resection and misclassification of the tumor were still significant on the treatment of SBT.

A virtual audit system for intensity-modulated radiation therapy credentialing in Japan Clinical Oncology Group clinical trials: A pilot study

PURPOSE

The Medical Physics Working Group of the Radiation Therapy Study Group at the Japan Clinical Oncology Group is currently developing a virtual audit system for intensity-modulated radiation therapy dosimetry credentialing. The target dosimeters include films and array detectors, such as ArcCHECK (Sun Nuclear Corporation, Melbourne, Florida, USA) and Delta4 (ScandiDos, Uppsala, Sweden). This pilot study investigated the feasibility of our virtual audit system using previously acquired data.

METHODS

We analyzed 46 films (32 and 14 in the axial and coronal planes, respectively) from 29 institutions. Global gamma analysis between measured and planned dose distributions used the following settings: 3%/3 mm criteria (the dose denominator was 2 Gy), 30% threshold dose, no scaling of the datasets, and 90% tolerance level. In addition, 21 datasets from nine institutions were obtained for array evaluation. Five institutions used ArcCHECK, while the others used Delta4. Global gamma analysis was performed with 3%/2 mm criteria (the dose denominator was the maximum calculated dose), 10% threshold dose, and 95% tolerance level. The film calibration and gamma analysis were conducted with in-house software developed using Python (version 3.9.2).

RESULTS

The means ± standard deviations of the gamma passing rates were 99.4 ± 1.5% (range, 92.8%-100%) and 99.2 ± 1.0% (range, 97.0%-100%) in the film and array evaluations, respectively.

CONCLUSION

This pilot study demonstrated the feasibility of virtual audits. The proposed virtual audit system will contribute to more efficient, cheaper, and more rapid trial credentialing than on-site and postal audits; however, the limitations should be considered when operating our virtual audit system.

Patient-reported outcome and quality of life research policy: Japan Clinical Oncology Group (JCOG) policy

Assessments of patient-reported outcomes and health-related quality of life in cancer clinical trials have been increasingly emphasized recently because patient and public involvement in cancer treatment development has been promoted by regulatory authorities and academic societies. To assess patient experiences during and after cancer treatment, there is interest in implementing patient-reported outcome and health-related quality of life assessments into cancer clinical trials. The Japan Clinical Oncology Group quality of life ad hoc committee previously created a version of the Quality of Life Assessment Policy in 2006. Recently, there has been increasing demand from Japan Clinical Oncology Group researchers to assess patient-reported outcome/health-related quality of life in clinical trials. Although guidelines are available regarding planning and reporting clinical trials that include patient-reported outcome/health-related quality of life as an endpoint, there are still issues regarding the lack of consensus on standardized methods for analysing and interpreting the results. Hence, it was considered necessary to reorganize the Japan Clinical Oncology Group patient-reported outcome/quality of life research committee and to revise the former patient-reported outcome/quality of life research policy to promote patient-reported outcome/health-related quality of life research in future Japan Clinical Oncology Group trials. The purpose of this Japan Clinical Oncology Group patient-reported outcome/quality of life research policy is to define patient-reported outcome/health-related quality of life research and provide guidelines for including patient-reported outcome/health-related quality of life as an endpoint in Japan Clinical Oncology Group trials.

Comparison of the International Workshop Criteria and the Response Evaluation Criteria in Solid Tumors for indolent B-cell lymphoma

BACKGROUND

[¹⁸F] fluorodeoxyglucose-positron emission tomography is incorporated in response criteria currently used for lymphoma; however, the primary endpoint in earlier phase study is an overall response, which includes the partial response of 50% shrinkage in two dimensions. Therefore, the measurement of target lesions is still prerequisite to determine the destiny of new, promising agents. Since required is calculating the sum of the product of bidimensional diameters of maximal six target lesions, the International Workshop Criteria (IWC) used as response evaluation in lymphoma is more time-consuming than the Response Evaluation Criteria in Solid Tumors (RECIST). This study aimed to examine whether the RECIST could replace the IWC using data from a phase II/III study of R-CHOP-21 versus R-CHOP-14 for advanced-stage indolent B-cell lymphoma, JCOG0203.

METHODS

To evaluate the degree of agreement between them, the Kappa coefficient (KC) was calculated. Excluding patients without target lesions for the RECIST following central pathological review, 269 patients were evaluable. We determined which criterion was more predictive for progression-free survival. The criterion showing the lower point estimate of the hazard ratio (HR) of a complete response (CR) vs. a non-CR was defined as more useful.

RESULTS

The KC between them was 0.34 (95% confidence interval [CI] 0.26-0.42); namely, indicating poor agreement. The HR of the IWC (0.47: 95% CI 0.33-0.68, log-rank test p < 0.001) was lower than that of the RECIST (0.64: 95% CI 0.45-0.89, p = 0.0075).

CONCLUSION

We conclude that unidimensional measurements cannot be substituted for the bidimensional ones for indolent lymphoma.

Geriatric Research Policy: Japan Clinical Oncology Group (JCOG) policy

Due to the rapid aging of Japan’s population, clinical research focusing on older patients with cancer is urgently needed. The Japan Clinical Oncology Group (JCOG) has conducted several such clinical trials, but there has been no formal policy for geriatric research. We have therefore established a JCOG policy for geriatric cancer research.

We defined the patient selection policy based on treatment tolerance and chronological age. Older patients are categorized into three conceptual groups: ‘fit patients’ who can undergo the same standard treatment given to younger patients, ‘frail patients’ for whom best supportive or palliative care is indicated and ‘vulnerable patients’ who fall between the fit and frail categories. Unmet needs often exist for vulnerable patients.

The policy recommends that study endpoints include not only survival but also other endpoints such as physical and cognitive function because the objective of therapy in older patients is not only extended life expectancy but also maintenance of the patient’s general condition. In this viewpoint, co-primary or composite endpoints that incorporate geriatric assessment in the study design are often applicable.

Study design will differ depending on the study population, clinical question, and treatment. Even for older patients, a randomized clinical trial is still the gold standard when the clinical question asks which treatment is better. An observational study of a broader population is applicable for investigating actual conditions of older patients.

This JCOG Geriatric Research Policy includes several practical solutions for various issues in geriatric research. We plan to revise this policy periodically to guide future geriatric research.

Multidisciplinary management of stage II-III gastric and gastro-oesophageal junction cancer

The aim of this manuscript is to discuss the viewpoint of the European Organisation for Research and Treatment of Cancer (EORTC) Gastric Cancer Taskforce and Japan Clinical Oncology Group (JCOG) Gastric Cancer Study Group on the current challenges in the multidisciplinary management of stage II-III gastric and gastro-oesophageal junction (GEJ) cancer. We seek to outline how these challenges are addressed in current trials of both groups. Key elements of future trials of EORTC and JCOG in this indication are described, and a joint vision on how multidisciplinary research of gastric and GEJ cancer patients should be organised is outlined.

Study risk assessment of Japan Clinical Oncology Group (JCOG) clinical trials using the European Organisation for Research and Treatment of Cancer (EORTC) study risk calculator

BACKGROUND

New Japanese ethical guidelines for medical researches and the Clinical Trials Act have come into effect and monitoring is mandated for intervention studies. Methods of monitoring can be modified according to a study risk, but there is no established method in Japan regarding how to assess a study risk. EORTC assesses a study risk using their own study risk calculator and classifies their trials into three categories. For each category, different levels of monitoring are applied. This project is aimed to assess the study risks of JCOG trials using the EORTC calculator.

METHODS

We selected clinical trials open to patient recruitment in JCOG as of Nov 2014. Each trial was scored based on the EORTC study risk calculator and classified into three risk categories; low, medium and high.

RESULTS

A total of 40 studies were included in the assessment. Twenty-seven studies (67.5%) were classified into low risk group, 12 (30%) in medium risk group, and only 1 (2.5%) in high risk group. Clinical trials evaluating multimodality therapy and/or using unapproved drugs tended to be scored higher and most of them were classified into medium or high risk group.

CONCLUSIONS

JCOG conducts central monitoring and site visit audit with sampling source data verification for every trial, which are almost compatible with the way in EORTC for the medium risk group. Because most of the JCOG studies were classified into low or medium risk group, the intensity of monitoring and audit in JCOG was considered as reasonable even from the EORTC perspective.

Current management of liver metastases from gastric cancer: what is common practice? New challenge of EORTC and JCOG

The role of multidisciplinary treatment including surgery for liver metastases from gastric cancer (LMGC) is controversial. Studies to answer this clinical question are increasing in number, but all published data thus far are based on retrospective analyses with limited sample sizes. Thus, the European Organisation for Research and Treatment of Cancer (EORTC) Gastrointestinal Tract Cancer Group (GITCG) and the Japan Clinical Oncology Group (JCOG) Stomach Cancer Study Group (SCSG) initiated a collaboration to develop an optimal treatment strategy for LMGC. Before planning a prospective study, a questionnaire was sent out to the network members of both groups in June 2016 to clarify current common practice in each region. Sixty-seven sites from 17 countries in the EORTC network and 55 sites from Japan responded. According to the survey, for patients with resectable LMGC without extrahepatic metastases, preoperative chemotherapy followed by resection of both primary (if still in place) and liver lesions was the preferred option for both the synchronous and the metachronous setting. For patients with unresectable LMGC, most of the sites recommended chemotherapy only. In this article, the detailed results of this survey are reported, shedding light on current community practice, and a joint EORTC-JCOG strategy of investigation is delineated.