Esophagogastric junction (EGJ) carcinomas develop along the border between the mediastinum and abdomen and can metastasize to both cavities due to anatomical characteristics. The endoscopic or surgical treatment for EGJ carcinoma is based on gastric carcinoma or esophageal carcinoma treatment depending on the medical institution. There are various opinions on the indication for additional treatments after endoscopic submucosal dissection and the extent of lymph node dissection during surgical treatment. EGJ carcinomas also have a feature that the clinical diagnosis (depth of invasion, location of tumor center, esophageal invasion length, etc.) is difficult, but important, for deciding the treatment method. In this session, speakers present the appropriate diagnosis, treatment algorithms, and treatment outcomes of each institution and assess the current state of treatment for EGJ carcinoma.

Currently, robotic gastric cancer surgery is performed only in limited number of institutions. Multi-degree of freedom in forceps and regulation system for tremor are raised as advantages, meanwhile, high cost, safety, and longer operation time are pointed out as drawbacks. There is no clear answer regarding its merits over conventional surgery. In Japan, a prospective study enrolling patients with cStage I/II gastric cancer was conducted as advanced medical treatment system, and accrual of patients has completed in 2017. Additionally, from now new surgical robots are expected to be on the market in a couple of years. In this symposium, advantages and disadvantages of robotic gastrectomy, as well as its future role will be presented.

The definition and indication about “conversion surgery” has been discussed for years. Stage IV gastric cancer patients with non-curative factor sometimes undergo surgery because of the recent development of intensive chemotherapy. However, detail of this treatment is still controversial. In this session, the current status and perspectives of “conversion surgery” is reported with outcome.

Experts from various countries will show state of the art of gastric cancer surgery.

Remarkable progress has been made in endoscopic diagnosis and treatment for gastric diseases in recent years. This session aims to provide a platform to discuss the current status and future directions on these topics with lectures by international distinguished experts.

Standard chemotherapy for gastric cancer includes cytotoxic agents, HER2 targeting therapy and VEGFR2 targeting therapy.
Also, immune check point inhibitors will be introduced in near future.
However, efficacy of these treatments is still not sufficient without patient’s enrichment and we have many negative trials with other agents.
So, more efficient strategy might be necessary based on its biology.
In this symposium, we discuss ongoing development of newer treatments for gastric cancer.

Progress in overall survival of patients with gastric cancer comes from not only development of new molecular targeting agents and immune-checkpoint inhibitors, but also development of new strategies with already approved agents. Clinical trials of neo-adjuvant chemotherapy and/or adjuvant chemotherapy, development of more powerful doublet or triplet chemotherapy, non-inferiority study for better QOL, trials for unfit patients and elderly patients, etc. are very important aiming at the best practice. These topics will be discussed among various regions and clinical trial groups.

To achieve "stop gastric cancer", development of precise risk diagnosis after H. pylori eradication, prediction of lymph node metastasis in early gastric cancers, prediction of responses to immune checkpoint inhibitors, and development of novel therapeutic strategy are important tasks. To address these tasks, clarification of molecular alterations in cancer cells have been considered important, but now growing attention is paid to immune cells infiltrating cancer tissues and fibroblasts present in cancer stromal tissues. Analytic technologies are also making constant progresses involving not only genomic analysis but also epigenomic analysis and immune cell characterization, and patient-derived xenografts (PDX) are now available. In this symposium, we will discuss research on multiple components of gastric cancer tissues to develop novel diagnostics and therapies.

The clinicopathology of gastric cancer is now changing dramatically as a result of introduction of companion diagnosis (CDx), genomic medicine, and AI technology into pathological diagnosis for patients’ management. Direction of future pathology of gastric cancer will be discussed in this symposium by researchers engaging in pathology.

The extent of dissection of mediastinal and abdominal lymph nodes, gastrectomy, and reconstruction methods should be appropriately selected according to the location and size of the tumor and histological type of esophagogastric junction (EGJ) carcinoma.
In addition to surgical treatment, preoperative and postoperative adjuvant chemotherapy are often performed in patients with advanced cancer. Squamous cell carcinoma is usually treated like esophageal cancer, and patients with adenocarcinoma are often treated according to the gastric cancer treatment. It is also useful for triplet combination chemotherapy and chemoradiotherapy to improve treatment outcomes for EGJ carcinoma. In this session, we discuss innovative ideas and new directions for treating EGJ carcinoma from minimally invasive surgery to multidisciplinary treatment.

The optimal therapeutic strategy for the gastric cancer patients with lavage cytology positive (CY1) has not been established. Surgery followed by adjuvant chemotherapy using S1 deems to be a standard therapy with the result of clinical trial (CCOG0301). Efficacy of neo-adjuvant chemotherapy will be evaluated by the result of JCOG0501. Recently doublet regimen is available as adjuvant chemotherapy. In this session, the therapeutic strategy for CY1 is discussed from the viewpoint of oncological outcomes.

Although a super-extended dissection can be safely performed with acceptable operative risks in Japan, advanced gastric cancer with para-aortic nodal involvement has a poor prognosis even after radical surgery. Currently preoperative chemotherapy with curative intent is essential for patients with PAN involvement. Up to the present date, the most common preoperative chemotherapy regimen is a combination of S1 and cisplatin. However, there are still some issues to be solved to obtain further improving. We would invite you to discuss future issues, based on the experiences in each facility.

Regarding reconstructive procedure after gastrectomy for gastric cancer, there are several methods depending on the type of gastric resection. Japanese gastric cancer treatment guidelines have no description about the standard reconstruction method. There are some reports of clinical trials comparing quality of life (QOL) and morbidity / mortality rate by BI and RY reconstruction after distal gastrectomy. However necessary and sufficient consideration has not been made on the reconstructive procedure after total or proximal gastrectomy. RY reconstruction is in widespread clinical use after total gastrectomy, while there is a plurality of options in case of proximal gastrectomy. In this session, we discuss the short and long term outcome after total or proximal gastrectomy corresponding to the difference in reconstruction with an emphasis on patient’s QOL.

There is no clear evidence of prospective trials on laparoscopic surgery for advanced gastric cancer. Therefore, the indication of laparoscopic surgery for advanced gastric cancer is still controversial. However, in some institutions, laparoscopic gastrectomy is applied to stage II, III tumor. Speakers discuss the two points. One is how to handle the tumor and to develop the surgical field. The other is the indication at the moment, problems and its solution based on middle, long term outcomes.

Postoperative adjuvant chemotherapy using S-1 has been established as a standard treatment for advanced gastric cancer patients these ten years. Recently, XELOX has been introduced as another standard regimen. ACTS-GC was carried out based on the 13th edition of Japanese Classification, but new classification (15th) has been proposed with modification staging system mainly in stage III. In order to establish new therapeutic strategy including pre or post-operative adjuvant chemotherapy for advanced gastric cancer patients, recent survival data based on 15th classification should be analyzed very soon. In this session, institutional analysis with the effect of postoperative adjuvant chemotherapy will be presented.

Life expectancy has been extended due to high standard of medical care in Asia. The proportion of elderly patients in gastric cancer gradually increased against a background of rapid graying of society. Hence, to develop treatment strategy for elderly gastric cancer patients is a vitally important issue. While discussions have been growing for an aggressive management to be extended, there are many difficult discussions that we should revise their strategy of focusing on untreated or supportive palliation since comorbidities or functional impairment are more prevalent. We hope that this session will allow for genuine discussions with all in attendance on what kinds of ethical and safe treatments will be provided to the further society.

Surgery for gastric stump cancer (GSC) has a high degree of difficulty. The range of lymph node dissection is different depending on the reconstruction method of initial surgery and its pathological result. It is sometimes necessary to perform combined resection of adjacent organs to complete radical operation. In recent years, it is reported that advanced GSC has poor prognosis compared to primary gastric cancer located in upper body. To verify a therapeutic efficiency of GSC is an important issue since completion gastrectomy applied to most advanced GSC leads to poor performance status and poor compliance with post-surgical treatment. This session will allow vigorous discussions with all in attendance focused on future multidisciplinary therapy for GSC.

Peritoneal dissemination has been estimated as non-curative factor hard to be overcome. Survival time can be elongated by the development of intraperitoneal treatment and systemic chemotherapy. In this session, current status and new challenge for this disease will be reported from various standpoints such as molecular biology, chemotherapy and surgery.

The optimal resection range for esophagogastric junction (EGJ) carcinoma remains controversial. The surgical procedures that can be selected include the proximal gastrectomy, lower esophagectomy with lower mediastinal lymph node dissection, and subtotal esophagectomy with upper and middle mediastinal lymph node dissection. In this session, speakers present videos for laparoscopic or thoracoscopic surgical techniques (lymph node dissection, reconstruction methods with consideration for quality of life, etc.) for EGJ carcinoma.

Following the results of JCOG 0110, in total gastrectomy for proximal gastric cancer that does not invade the greater curvature, splenectomy should be avoided as it increases operative morbidity without improving survival. Therefore, laparoscopic total gastrectomy will spread widely in the future, and could be indicated to advanced gastric cancer. However, in advanced proximal gastric cancer that invades greater curvature, splenectomy is necessary for complete dissection of the No.10 LNs. In this session, Expert surgeons show the knacks and pitfalls of total gastrectomy with splenectomy.

The reconstruction method of LATG is more difficult than that of LADG. Various reconstruction methods are proposed, however, an optimal procedure has yet to be established . Through this session, experts show the knacks and pitfalls of reconstruction and compare pros and cons of each reconstruction method.

GISTs are mostly caused by gain-of-function mutations either in the c-kit or PDGFRA gene. Imatinib, a molecularly targeted agent for these tyrosine kinases, has revolutionized the treatment of GISTs, resulting in the remarkably improved prognosis of GIST patients. The guidelines from NCCN and ESMO have been available since 2004, however, it is considered that these guidelines are not always adaptable and sometimes unsuitable for Asian GIST patients. Finally, in 2016, the Asian GIST guidelines has been published. In this great session, we will have outstanding Asian GIST experts to present the current status and future directions of the diagnosis and treatment of GISTs.