Gastric cancer treatment guidelines in Japan

Endoscopic and Surgical Treatment in Early Gastric Cancer: The Gray Zone in Treatment Decision-Making from the Perspectives of Endoscopists

To treat early gastric cancer, one must choose between endoscopic treatment and surgical treatment. Endoscopic treatment has been developing significantly since the late 1990s and has made great progress up to the present. However, many patients with early gastric cancer still undergo unnecessary surgery or endoscopic procedures. This is due to the existence of a "gray zone" of ambiguities between endoscopic and surgical treatment. These ambiguities arise because the important factors in determining the treatment for early gastric cancer can only be fully understood after endoscopic or surgical resection or because of discrepancies between the factors identifiable before treatment and those identifiable after treatment. This article aims to explore these ambiguous factors and discuss methods and efforts to reduce them.

Temporal changes in regional variations in cancer survival rates in Osaka, Japan (1997-2015)

The variation in survival rates among patients with cancer based on residential areas has become a significant concern globally. Japan's Basic Plan to Promote Cancer Control Programs (BPPCCP), implemented in 2007, aimed to reduce this variation by designating cancer care hospitals in each cancer medical area (CMA) where patients resided. From the Osaka Cancer Registry data, we extracted 407,489 patients aged 15-74 years with cancer who received treatment in Osaka Prefecture between 1997 and 2015 and analyzed regional variations in survival rates for each patient's residential CMA before and after the implementation of the BPPCCP. By standardizing the distribution of the patients' background factors (sex, age, stage, and socioeconomic status) to the distribution of the whole prefecture, 5-year relative survival rates for each CMA were calculated, and regional variations were assessed. Before BPPCCP, survival variation reached 2.00 percentage points (p-values < 0.05); post-BPPCCP, it decreased to 0.98 percentage points and was no longer significant. In conclusion, the introduction of the BPPCCP in 2007 may have reduced regional variation in the survival rate of patients with cancer in Osaka Prefecture. Measures such as the BPPCCP could potentially equalize the cancer care delivery system.

The clinical significance assessment of the transverse lymph node metastasis in gastric cancer: The establishment and validation of nomogram from a single clinical medical center

BACKGROUND

Lymph node metastasis is an important route for gastric cancer metastasis. The clinical significance of transverse lymph node metastasis (TLNM) is still unclear.

AIMS

This study investigates effects of TLNM on the prognosis of GC patients and establishes two nomograms for evaluating the prognosis of GC patients and for predicting the risk clinicopathological factors to TLNM based on a Chinese medical database.

METHODS

A total of 902 GC patients with lymph node metastasis (LNM) who underwent R0 gastrectomy was included in this study. According to results of Cox proportional hazards analyses and logistic regression analyses, the prognostic and the predictive nomograms were established and validated.

RESULTS

The overall survival of patients with TLNM was significantly worse than those without TLNM (P < 0.001) and similar to patients with extra-gastric LNM (P > 0.05). TLNM independently influenced prognosis of GC patients. Prognostic and predictive nomograms were established and validated. Both nomograms were proven that have high accuracy by calculating each AUC (Area Under Cure) value. Calibration curves aligned well with actual outcomes. DCA (Decision Curve Analyses) analyses indicated the high clinical utility.

CONCLUSION

These nomograms offer precise survival and TLNM occurrence predictions, which may aid clinical decisions.

Pathology and Clinical Relevance of Gastric Epithelial Dysplasia

Gastric dysplasia is defined as an unequivocally neoplastic epithelium. Dysplastic lesions are characterized by cellular atypia reflective of abnormal differentiation and disorganized glandular architecture. The last few years have been marked by a refinement of the prognosis and risk of progression of gastric dysplasia and the recognition of novel morphologic patterns of dysplasia. Determination of the correct diagnosis and grade of dysplasia are critical steps since it will be predicting the risk of malignant transformation and help tailor appropriate surveillance strategy. This review describes the morphologic characteristics of conventional dysplasia and nonconventional gastric dysplasia that have been more recently characterized.

Risk factors for death from other diseases after curative gastrectomy and lymph node dissection for gastric cancer

BACKGROUND

Recent advances in treatment are expected to bring a cure to more patients with gastric cancer (GC). Focusing on the risk of death from other diseases (DOD) has become a crucial issue in patients cured of GC. The aim of this study was to elucidate the risk factors for DOD in patients who underwent curative gastrectomy with lymph node dissection for GC.

METHODS

We enrolled 810 patients who underwent curative gastrectomy with lymph node dissection for GC from January 1990 to December 2014 and had no recurrence or death of GC until December 2019. We investigated the risk factors for DOD defined as death excluding death from a malignant neoplasm, accident, or suicide after gastrectomy, focusing on the perioperative characteristics at gastrectomy.

RESULTS

Among 315 deaths from any cause, 210 died from diseases other than malignancy, accidents and suicide. The leading cause of DOD was pneumonia in 54 patients (25.7%). The actual survival period in 167 patients (79.5%) with DOD was shorter than their estimated life expectancy at gastrectomy. Multivariate analysis revealed that a high Charlson Comorbidity Index score (score 1-2: hazard ratio [HR] 2.192, 95% confidence interval [CI] 1.713-2.804, P < 0.001 and score ≥ 3: HR 4.813, 95% CI 3.022-7.668, P < 0.001), total gastrectomy (HR 1.620, 95% CI 1.195-2.197, P = 0.002) and the presence of postoperative complications (HR 1.402, 95% CI 1.024-1.919, P = 0.035) were significant independent risk factors for DOD after gastrectomy for GC, in addition to age of 70 years or higher, performance status of one or higher and body mass index less than 22.0 at gastrectomy.

CONCLUSIONS

Pneumonia is a leading cause of DOD after curative gastrectomy and lymph node dissection for GC. Paying attention to comorbidities, minimizing the choice of total gastrectomy and avoiding postoperative complications are essential to maintain the long-term prognosis after gastrectomy.

Differences of clinical features and outcomes between male and female elderly patients in gastric cancer

Although the average life span differs between males and females, little is known about differences in clinical features and short and long-term outcomes between elderly male and female gastric cancer patients. This study was designed to clarify these issues to identify the possibility for sex-based treatment strategies in elderly gastric cancer patients. This study included 295 consecutive elderly gastric cancer patients (75 years or older) who underwent curative gastrectomy between 1997 and 2016. We defined postoperative complications as Clavien-Dindo classification grade II or higher. Comorbidities were present in 67% of all patients. Males tended to have more comorbidities than females (P = 0.077). Male patients had significantly more upper gastric cancers (P = 0.001), a higher incidence of postoperative complications (P = 0.045), and poorer prognoses than females (P = 0.003). Multivariate analysis revealed that being male was an independent risk factor for postoperative complications (Odds ratio 2.5, P = 0.045) and a poor prognostic factor (Hazard ratio 1.81, P = 0.008). Patients who underwent limited surgery without postoperative complications tended to have a better prognosis than patients receiving standard surgery with postoperative complications (3-year overall survival: 78% vs. 55%, P = 0.156). Male was an independent risk factor for postoperative complications and an independent poor prognostic factor in elderly gastric cancer patients. To avoid postoperative complications, the limited surgery might be justified for high-risk elderly male patients.

Multimodal prehabilitation to improve the clinical outcomes of frail elderly patients with gastric cancer: a study protocol for a multicentre randomised controlled trial (GISSG+2201)

INTRODUCTION

Gastric cancer (GC) diagnosed in the elderly population has become a serious public health problem worldwide. Given the combined effects of frailty and the consequences of cancer treatment, older individuals with GC are more likely than young patients to suffer from postoperative complications and poor clinical outcomes. Nutrition, functional capacity and psychological state-based multimodal prehabilitation, which is dominated by Enhanced Recovery After Surgery (ERAS) pathway management, has been shown to reduce postoperative complications, promote functional recovery and decrease hospitalisation time in certain malignancies. However, no previous studies have investigated the clinical application of multimodal prehabilitation in frail older patients with GC.

METHODS AND ANALYSIS

The study is a prospective, multicentre randomised controlled trial in which a total of 368 participants who meet the inclusion criteria will be randomised into either a prehabilitation group or an ERAS group. The prehabilitation group will receive multimodal prehabilitation combined with ERAS at least 2 weeks before the gastrectomy is performed, including physical and respiratory training, nutritional support, and therapy and psychosocial treatment. The ERAS group patients will be treated according to the ERAS pathway. All interventions will be supervised by family members. The primary outcome measures are the incidence and severity of postoperative complications. Secondary outcomes include survival, functional capacity and other short-term postoperative outcomes. Overall, the multimodal prehabilitation protocol may improve functional capacity, reduce the surgical stress response and concomitant systemic inflammation, and potentially modulate the tumour microenvironment to improve short-term and long-term clinical outcomes and patients' quality of life.

ETHICS AND DISSEMINATION

All procedures and participating centres of this study were approved by their respective ethics committees (QYFYKYLL 916111920). The final study results will be published separately in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05352802.

Gastric Cancer: Correlation of Histologic Type with Commonly Used Prognostic Variables

Background: Gastric cancer is one of the most common cancers among Iranian men and women. Objectives: The aim here was to investigate different histopathologic types and features of this cancer in association with selected prognostic variables. Methods: A retrospective cross-sectional study was performed to reevaluate the pathologic samples of 100 cases of gastric cancer referred to Shohadaye Tajrish Hospital, Tehran, Iran from 2017 to 2022. Results: We evaluated 100 cases of gastric cancer in this study. They had a mean age of 62.4 ± 13.44 years old (range 28 - 84 years) and were mostly men (n = 66, 66 %). On histopathologic evaluation, tubular carcinoma was the most common type (n = 45, 45%). We found a statistically significant correlation between the histologic type and perineural invasion (P-value = 0.024), lymphovascular invasion (P-value < 0.001), tumoral involvement of surgical margin (P-value = 0.012 ), infiltration depth of the primary tumor (pT) (P-value = 0.049) , number of metastatic lymph nodes (pN) (P-value = < 0.001) , tumor location in the antrum (P-value=0.033) and body (P-value = 0.013) , and tumor size (P-value = 0.002 and P-value = 0.031 in small and large size groups respectively). Conclusions: According to the findings, histologic type of gastric cancer correlates with perineural invasion, lymphovascular invasion, tumoral involvement of the surgical margin, pT, pN, and tumor location and size.

The Predictive Value of a New Inflammatory-Nutritional Score for Quality of Life after Laparoscopic Distal Gastrectomy for Gastric Cancer

We explored the predictive value of various inflammatory-nutritional indicators for postoperative quality of life (QoL) in gastric cancer (GC) patients undergoing laparoscopic distal gastrectomy (LDG) and developed a novel inflammatory-nutritional score (INS). In this study, 156 GC patients who underwent LDG were included. We used multiple linear regression to analyze the correlation between postoperative QoL and inflammatory-nutritional indicators. Least absolute shrinkage and selection operator (LASSO) regression analysis was performed to construct INS. Hemoglobin was positively correlated with physical functioning (β =8.5; p = 0.003) and cognitive functioning (β = 3.5; p = 0.038) 3 mo, after surgery. Prognostic nutritional index (PNI) was positively associated with global health status (β =5.8; p = 0.043). Albumin-alkaline phosphatase ratio (AAPR) was negatively correlated with emotional functioning 12 mo, after surgery (β = -5.7; p = 0.024). Neutrophil-lymphocyte ratio (NLR), Lymphocyte- monocyte ratio (LMR), AAPR, hemoglobin and PNI were selected using LASSO regression analysis to construct INS. The C-index values of the model in the training group and the validation group were 0.806 (95% CI, 0.719-0.893) and 0.758 (95% CI: 0.591-0.925), respectively. INS had particular predictive value for postoperative QoL in patients undergoing LDG and provided a reference for risk stratification and clinical practice.

Current standards of surgical management of gastric cancer: an appraisal

PURPOSE

Gastric cancer (GC) is the fifth most common malignancy worldwide and portends a grim prognosis due to a lack of appreciable improvement in 5-year survival. We aimed to analyze the available literature and summarize the current standards of surgical care for curative and palliative intent treatment of GC.

METHODS

We conducted a systematic search on the PubMed database for studies on the management of GC.

RESULTS

Endoscopic resection is an acceptable treatment option for T1a tumors. The role of optimal resection margin for GC remains unclear. D2 lymph node dissection remains the standard of care with splenectomy needed selectively for splenic hilum involvement. A distal pancreatic resection should be avoided. The advantage of bursectomy and omentectomy in GC surgery is not clear. Multi-visceral resection may be considered for locally advanced GC in carefully selected patients. Minimally invasive approaches are non-inferior to open surgery. Surgery should be abandoned prior even in metastatic GC within the frame of multimodal therapy approach.

CONCLUSION

Various trials have conclusively shown improved patient outcomes when well-established surgical standards are followed.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Prognosis of Stage IV Gastric Cancer Patients

Aim. This study evaluated the survival of gastric cancer patients with metastasis to the hepatoduodenal, retropancreatic, mesenteric, and para-aortic lymph nodes. Materials and methods. We analyzed the survival rate of 435 gastric cancer patients who underwent operation from 2001 to 2010 at the Department of Surgery, Chonnam National University Hospital. There were 43, 25, 16, and 55 patients with metastasis to the hepatoduodenal, retropancreatic, mesenteric, and para-aortic nodes, respectively. Results. Based on tumor location, metastasis to the para-aortic lymph nodes was more common in upper-third cancer, and that to the hepatoduodenal lymph nodes was more common in lower-third cancer. The survival rate of patients with non-regional lymph node metastasis was better than that of patients with hepatic metastasis or peritoneal dissemination (p < 0.05). Conclusion. We recommend performing a more extended lymphadenectomy than a D2 lymphadenectomy in patients with advanced gastric cancer those having metastasis to the hepatoduodenal nodes.

Characteristics of gastric cancer gut microbiome according to tumor stage and age segmentation

With the development of 16S rRNA technology, gut microbiome evaluation has been performed in many diseases, including gastrointestinal tumors. Among these cancers, gastric cancer (GC) exhibits high morbidity and mortality and has been extensively studied in its pathogenesis and diagnosis techniques. The current researches have proved that the gut microbiome may have the potential to distinguish GC patients from healthy patients. However, the change of the gut microbiome according to tumor node metastasis classification (TNM) has not been clarified. Besides, the characteristics of gut microbiome in GC patients and their ages of onset are also ambiguous. To address the above shortcomings, we investigated 226 fecal samples and divided them according to their tumor stage and onset age. The findings revealed that surgery and tumor stage can change the characteristic of GC patients' gut microbiota. In specific, the effect of surgery on early gastric cancer (EGC) was greater than that on advanced gastric cancer (AGC), and the comparison of postoperative microflora with healthy people indicated that EGC has more differential bacteria than AGC. Besides, we found that Collinsella, Blautia, Anaerostipes, Dorea, and Lachnospiraceae_ND3007_group expressed differently between EGC and AGC. More importantly, it is the first time revealed that the composition of gut microbiota in GC is different between different onset ages. KEY POINTS: •Gut microbiota of gastric cancer (GC) patients are either highly associated with TNM stage and surgery or not. It shows surgery has more significant changes in early gastric cancer (EGC) than advanced gastric cancer (AGC). •There existed specific gut microbiota between EGC and AGC which may have potential to distinguish the early or advanced GC. •Onset age of GC may influence the gut microbiota: the composition of gut microbiota of early-onset gastric cancer (EOGC) and late-onset gastric cancer (LOGC) is significantly different.

Does the addition of Braun anastomosis to Billroth II reconstruction on laparoscopic-assisted distal gastrectomy benefit patients?

BACKGROUND

Operation is the primary therapeutic option for patients with distal gastrectomy. Braun anastomosis is usually performed after Billroth II reconstruction, which is wildly applied on distal gastrectomy because it is believed to benefit patients. However, studies are needed to confirm that.

AIM

To identify whether the addition of Braun anastomosis to Billroth II reconstruction on laparoscopy-assisted distal gastrectomy benefits patients.

METHODS

A total of 143 patients with gastric cancer underwent laparoscopy-assisted distal gastrectomy at Centre 1 of PLA general hospital between January 2015 and December 2019. Clinical data of the patients were collected, and 93 of the 143 patients were followed up. These 93 patients were divided into two groups: Group 1 (Billroth II reconstruction, 33 patients); and Group 2 (Billroth II reconstruction combined with Braun anastomosis, 60 patients). Postoperative complication follow-up data and relevant clinical data were compared between the two groups.

RESULTS

There were no significant differences between Group 1 and Group 2 in postoperative complications (6.1% vs 6.7%, P = 0.679), anal exhaust time or blood loss. The follow-up prevalence of reflux gastritis indicated no significant difference between Group 1 and Group 2 (68.2% vs 51.7%, P = 0.109). The follow-up European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 scores revealed no evident difference between Group 1 and Group 2 as well. Group 1 had a shorter operating time than Group 2 on average (234.6 min vs 262.0 min, P = 0.017).

CONCLUSION

Combined with Billroth II reconstruction, Braun anastomosis has been applied due to its ability to reduce the prevalence of reflux gastritis. Whereas in this study, the prevalence of reflux gastritis showed no significant difference, leading to a conclusion that under the circumstance of Braun anastomosis costing more time and more money, simple Billroth II reconstruction should be widely applied.

Adverse impact of postoperative intra-abdominal infectious complications on cancer recurrence-related survival after curative gastric cancer surgery

BACKGROUND

This study aimed to evaluate the impact of postoperative intra-abdominal infectious complications (PICs) on survival after surgery for gastric cancer.

METHODS

A total of 152 patients who underwent curative gastrectomy for gastric cancer were included. The effect of clinicopathological features and PICs on recurrence-free survival (RFS) and overall survival (OS) were investigated.

RESULTS

The median age was 67 years. The pathological stage was stage I (61), II (40), and III (51). Thirty-two patients (21.1%) had PICs: 9, pancreatic fistula; 14, anastomotic leakage; and 17, intra-abdominal abscess. The five-year RFS and OS rates were significantly lower in patients with PICs than in those without PICs (63.4 vs. 85.6%; p < 0.01 and 56.4 vs. 80.3%; p < 0.01, respectively). In multivariate analysis, intraoperative blood loss was an independent prognostic factor for PICs.

CONCLUSIONS

Patients with PICs had worse clinical outcomes. Reducing intraoperative bleeding may improve the prognosis of gastric cancer.

Extensive Dissection at No. 12 Station During D2 Lymphadenectomy Improves Survival for Advanced Lower-Third Gastric Cancer: A Retrospective Study From a Single Center in Southern China

BACKGROUND

D2 lymphadenectomy including No. 12a dissection has been accepted as a standard surgical management of advanced lower-third gastric cancer (GC). The necessity of extensive No. 12 nodes (No. 12a, 12b, and 12p) dissection remains controversial. This study aims to explore its impact on long-term survival for resectable GC.

METHODS

From 2009 to 2016, 353 advanced lower-third GC patients undergoing at least D2 lymphadenectomy during a radical surgery were included, with 179 patients receiving No. 12a, 12b, and 12p dissection as study group. A total of 174 patients with No. 12a dissection were employed as control group. Surgical and long-term outcomes including 90-day complications incidence, therapeutic value index (TVI), 3-year progression-free survival (PFS), and 5-year overall survival (OS) were compared between both groups.

RESULTS

No. 12 lymph node metastasis was observed in 20 (5.7%) patients, with 10 cases in each group (5.6% vs. 5.7%, p = 0.948). The metastatic rates at No. 12a, 12b, and 12p were 5.7%, 2.2%, and 1.7%, respectively. The incidence of 90-day complications was identical between both groups. Extensive No. 12 dissection was associated with increased TVI at No. 12 station (3.9 vs. 0.6), prolonged 3-year PFS rate (67.0% vs. 55.9%, p = 0.045) and 5-year OS rate (66.2% vs. 54.0%, p = 0.027). The further Cox-regression analysis showed that the 12abp dissection was an independent prognostic factor of improved survival (p = 0.026).

CONCLUSION

Adding No. 12b and 12p lymph nodes to D2 lymphadenectomy might be effective in surgical treatment of advanced lower-third GC and improve oncological outcomes compared with No. 12a-based D2 lymphadenectomy.

Laparoscopic gastrectomy for gastric cancer: has the time come for considered it a standard procedure?

Radical gastrectomy with an adequate lymphadenectomy is the main procedure which makes it possible to cure patients with resectable gastric cancer. A number of randomized controlled trials and meta-analysis provide phase III evidence that laparoscopic gastrectomy is technically safe and that it yields better short-term outcomes than conventional open gastrectomy for early-stage gastric cancer. At present, laparoscopic gastrectomy is considered a standard procedure for early-stage gastric cancer, especially in Asian countries. On the other hand, the use of minimally invasive techniques is still controversial for the treatment of more advanced tumours, principally due to existing concerns about its oncological adequacy and capacity to carry out an adequately extended lymphadenectomy. Additional high-quality studies comparing laparoscopic gastrectomy versus open gastrectomy for gastric cancer have been recently published, in particular concerning the latest results obtained by laparoscopic approach to advanced gastric cancer. It seems very useful to update the review of literature in light of these new evidences for this subject and draw some considerations.

Surgical and survival outcomes after laparoscopic and open gastrectomy for serosa-invasive Siewert type II/III esophagogastric junction carcinoma: a propensity score matching analysis

BACKGROUND

The potential advantage of laparoscopic gastrectomy (LG) compared with open gastrectomy (OG) for serosa-invasive (pT4a) Siewert type II and III adenocarcinoma of the esophagogastric junction (AEG) remains uncertain. Thus, the purpose of this study was to investigate the short- and long-term outcomes of LG compared to OG for pT4a Siewert type II/III AEG cancers.

METHODS

We retrospectively evaluated 283 patients with pathological confirmed T4a Siewert type II and type III AEG who underwent LG or OG in our center between January 2004 and September 2015. The short- and long-term outcomes were compared between the groups using a 1:1 matched propensity score matching method (PSM).

RESULTS

The LG group had a longer operation time, less estimated blood loss, less time to first flatus, less time to start liquid diet, less time to first ambulation, and shorter length of incision than the OG group. The conversion rates were 5.4% in the LG groups. There was no significant difference in the overall complication rate between the LG and OG groups. The 5-year overall survival (OS) and the 5-year disease-free survival (DFS) were comparable between the LG and OG groups (35.4% vs 32.1%, p = 0.541; 34.1% vs 31.0%, p = 0.523, respectively). There was no significant difference in the recurrence rate and pattern between the LG and OG groups.

CONCLUSIONS

Laparoscopic gastrectomy is associated with better short-term outcomes and similar long-term outcomes for pT4a Siewert type II/III AEG. This study reveals that LG could be a safe and feasible option for pT4a Siewert type II/III AEG compared to OG.

Adjuvant chemotherapy indications for stage I gastric cancer patients with negative lymph node

PURPOSE

Whether adjuvant chemotherapy (AC) has a survival benefit for pathological stage Ⅰ (T1N0 and T2N0) gastric cancer (GC) patients with negative lymph node (N0) remains controversial.

METHODS

Patients with surgically resected, histologically confirmed pT1N0 and pT2N0 GC between January 2011 and December 2017 at the National Cancer Center, China, were retrospectively reviewed.

RESULTS

A total of 1601 patients who met the inclusion criteria were identified. Independent risk factors for reduced overall survival (OS) identified in the Cox regression analysis were male sex (hazard ratio [HR] 1.454, 95% confidence interval [CI] 1.127-1.876), age ≥ 65 years (HR 1.367; 95% CI 1.071-1.744 ), T2 stage (HR 1.283; 95% CI 1.005-1.638), tumor size > 3 cm (HR 1.704; 95% CI 1.346-2.158), examined lymph nodes (EN) ≤ 15 (HR 1.327; 95% CI 1.058-1.664), and non-signet ring cell carcinoma (Non-SRCC) (HR 1.639; 95% CI 1.123-2.392). While only T2 stage (HR 1.410; 95% CI 1.026-1.936), tumor size > 3 cm (HR 1.755; 95% CI 1.285-2.397), examined lymph nodes (EN) ≤ 15 (HR 1.489; 95% CI 1.101-2.015) were independent risk factors for cause-specific survival (CSS). We divided patients with pT2N0 into four sub-categories according to two significant prognostic factors (size and EN) and found that only patient in group 3 (EN ≤ 15, size >3 cm) with improved CSS benefit from AC (p = 0.049). More significant CSS benefit from AC was identified in Non-SRCC patients within group 3 (p = 0.034).

CONCLUSION

An additional survival benefit related to AC is expected for selected pT2N0 patients. Non-SRCC patients with EN ≤ 15 and tumor size >3 cm may be particularly appropriate candidates for AC.

Short-Term Clinical Efficacy of Neoadjuvant Chemotherapy Combined With Laparoscopic Gastrectomy for Locally Advanced Siewert Type II and III Adenocarcinoma of the Esophagogastric Junction: A Retrospective, Propensity Score-Matched Study

Background

Laparoscopic gastrectomy (LG) has been increasingly used for the treatment of locally advanced Siewert type II and III adenocarcinoma of the esophagogastric junction (AEG). However, whether LG can achieve the same short-term efficacy in the treatment of patients who receive neoadjuvant chemotherapy (NACT) remains controversial. Thus, the aim of this study was to investigate the clinical outcomes of NACT combined with LG for Siewert type II and III AEG.

Methods

This retrospective study identified patients with locally advanced Siewert type II and III AEG diagnosed between May 2011 and October 2020 using the clinical tumor-node-metastasis (cTNM) staging system. The short-term outcomes were compared between the matched groups using a 1:3 propensity score matching (PSM) method, which was performed to reduce bias in patient selection.

Results

After PSM, 164 patients were selected, including 41 in the NACT group and 123 in the LG group. The baseline characteristics were similar between the two groups. Compared with the LG group, the NACT group exhibit a smaller tumor size and significantly less advanced pathological tumor classification and nodal classification stages. The time to first flatus of the NACT group was significantly shorter, but the hospital stay was significantly longer than that of the LG group. The NACT group showed similar overall (29.3% vs 25.2%, P=0.683), systemic (24.4% vs 21.1%, P=0.663), local (12.2% vs 9.8%, P=0.767), minor (19.5% vs 19.5%, P=1.000) and major (9.8% vs 5.7%, P=0.470) complications as the LG group. Subgroup analyses showed no significant differences in most stratified parameters. Operation time≥ 300 minutes was identified as an independent risk factor for overall complications. Age≥ 60 years was identified as an independent risk factor for major complications.

Conclusion

NACT combined with LG for AEG does not increase the risk of postoperative morbidity and mortality compared with LG.

POU2F1 Promotes Cell Viability and Tumor Growth in Gastric Cancer through Transcriptional Activation of lncRNA TTC3-AS1

POU domain, class 2, transcription factor 1 (POU2F1) is involved in the development of gastric cancer (GC). However, the molecular mechanism has not been fully elucidated. Here, we identified a novel lncRNA named TTC3-AS1 that was potentially regulated by POU2F1 and investigated their roles in GC progression. Bioinformatics analysis suggested that high expression of POU2F1 predicted poor prognosis in patients with GC. We further screened out an lncRNA TTC3-AS1 that may be transcriptionally activated by POU2F1 according to the JASPAR database, and POU2F1 and TTC3-AS1 were highly expressed in GC cells and tissues compared with normal controls (NCs). Function analysis revealed that both POU2F1 and TTC3-AS1 played oncogenic roles by promoting cell viability, migration, and invasion in GC. qRT-PCR analysis showed that POU2F1 improved the expression of TTC3-AS1 in GC cells, while TTC3-AS1 knockdown or overexpression had no effect on POU2F1 expression. The results of chromatin immunoprecipitation and DNA-affinity precipitation assays indicated that POU2F1 directly bound to the promoter region of TTC3-AS1 and activated its transcription. TTC3-AS1 knockdown neutralized the protumor effects of POU2F1 overexpression in GC cell lines as well as mouse models of GC, which suggested that TTC3-AS1 mediates the oncogenic function of POU2F1. In summary, POU2F1 promoted GC progression by transcriptionally activating TTC3-AS1; thus, this study provided a new perspective for the mechanism of GC progression.

High frequency of bone recurrence as an initial recurrence site after radical surgery in T1N3 gastric cancer: a propensity score matching analysis

PURPOSE

T1 gastric cancer (GC) with seven or more metastatic lymph nodes is extremely rare, and very few clinical studies have been conducted to evaluate the clinicopathological features of their recurrence.

METHODS

We retrospectively analyzed the outcomes of T1 GC and T2-4 GC patients who had multiple nodal metastases after radical surgery from 2006 to 2020. Propensity score matching was performed to compare the two groups of patients.

RESULTS

After propensity score matching, 18 of 22 patients in the T1 group and 36 of 144 patients in the T2-4 group were selected. Recurrence occurred in six patients (33.3%) in the T1 group. In the T1 group, the most common site of initial recurrence was bone (15.0%). The prevalence of bone recurrence was significantly higher in the T1 group than in the T2-4 group (P = 0.02). The median interval time between radical surgery and bone recurrence was 24 months, and the median survival time after bone recurrence was 14 months.

CONCLUSION

Bone recurrence was more frequently identified as an initial recurrence site in T1 GC cases with multiple metastases after radical surgery compared with that in T2-4 GC cases. Careful attention should be paid to postoperative bone recurrence in the long-term postoperative course of these patients.

Comparison of delta-shaped anastomosis and Billroth I reconstruction after laparoscopic distal gastrectomy for gastric cancer

Background

This study intends to compare the short-term effects and long-term survival of gastric cancer patients who underwent delta-shaped anastomosis (DA) and Billroth I reconstructions after laparoscopic distal gastrectomy.

Methods

We retrospectively collected data from 257 patients with gastric cancer who underwent laparoscopic distal gastrectomy between January 2013 and December 2017. Patients were classified into 2 groups according to the reconstruction method used: the DA group (n=91) and the Billroth I group (n=166). The clinical data, short-term efficacy, and long-term results were compared between the 2 groups.

Results

The operation time (P<0.001) and the post-operative length of hospital stay (P<0.001) were shorter in the DA group than in the Billroth I group. The time to the first oral intake of a soft diet after surgery was earlier in the DA group than in the Billroth I group (P=0.014). Kaplan-Meier (log-rank test) analysis showed no significant difference in the 5-year survival rates between the 2 groups for patients at the same pathological stage. Multivariate analysis showed that abnormal carcinoembryonic antigen (CEA) (P=0.006), chemotherapy (P<0.001), T stage (P<0.001), and N stage (P<0.001) were independent prognostic factors for survival.

Conclusions

DA and Billroth I are feasible and safe reconstruction methods of the digestive tract after gastric cancer. DA is the recommended reconstruction method for laparoscopic distal gastrectomy.

Laparoscopic versus open gastrectomy for serosa-invasive gastric cancer: A single-center retrospective cohort study

BACKGROUND

Whether laparoscopic gastrectomy is suitable for patients with serosa-invasive gastric cancer remains controversial. We performed this study to evaluate the short- and long-term outcomes after laparoscopic gastrectomy compared with after open gastrectomy.

METHODS

We retrospectively analyzed 906 consecutive patients with serosa-invasive gastric cancer from January 2004 to December 2014 in our center, who underwent laparoscopic gastrectomy or open gastrectomy with D2 lymphadenectomy. After propensity score matching, 334 patients were included in each group. Surgical conditions and short- and long-term results were compared.

RESULTS

Laparoscopic gastrectomy was associated with less estimated blood loss and longer operation time, while the number of harvested lymph nodes was not significantly different between laparoscopic gastrectomy and open gastrectomy. Patients who underwent laparoscopic gastrectomy had an earlier time to first flatus, first diet, and first ambulation and were discharged earlier. Overall and pulmonary postoperative complication rates were lower in the laparoscopic gastrectomy group. With a minimum follow-up of 60 months, the 5-year overall survival was 39.3% in the laparoscopic gastrectomy group and 34.3% in the open gastrectomy group, and the 5-year disease-free survival was 36.4% in the laparoscopic gastrectomy group and 32.7% in the open gastrectomy group. Laparoscopic gastrectomy was associated with better 5-year overall survival in patients aged ≥60 years. The overall recurrence rates and patterns were not significantly different between the 2 groups.

CONCLUSION

Laparoscopic gastrectomy is an alternative surgical approach for patients with serosa-invasive gastric cancer in terms of short-term outcomes and long-term survival, and it might be more advantageous for certain populations.

Contribution of chemotherapy to improved prognosis in stage 4 gastric cancer: trend analysis of a regional population-based cancer registry in Japan

OBJECTIVES

Little is known about time trends in the prognosis of gastric cancer (GC), since the introduction of new chemotherapeutic agents. This study aimed to analyze how the increased number of available chemotherapeutic options affected the prognosis of GC and which patient types benefited within in a large population.

METHODS

From a population-based cancer registry in Japan, 35,751 cases of GC were identified. Of these, 8214 cases were stage 4. The time trend for 3-year survival in stage 4 GC according to patient characteristics (age and tumor location) was estimated in relation to the introduction of new anticancer drugs. Multiple imputation was performed for sensitivity analysis to strengthen the missing data. In addition, we estimated the 5-year survival rate for distal-GC (DGC) and proximal-GC (PGC), and the hazard ratio (HR) was estimated by Cox proportional hazard model.

RESULTS

Improvement of overall survival was accelerated in stage 4 cases over time. The prognosis was improved from 11.4% to 13.2%, subsequent to the approval of several oncologic drugs since 2009. Younger patients were more likely to have improved survival rates in response to the increase in chemotherapy options (< 60-year-old, 5.4%: 60-70, 2.2%; 70-80, 0.3%) from 2007 to 2015. The HR for DGC vs. PGC was 1.11 (95% CI 1.08-1.15), and PGC showed a higher rate of improved outcomes (2.4% vs. 0.6%).

CONCLUSIONS

This analysis showed that improvement in the GC survival rate was accelerated by the introduction of new chemotherapeutic strategies and it was most evident among younger patients and in patients with PGC.

Impact of examined lymph node count on staging and long-term survival of patients with node-negative stage III gastric cancer: a retrospective study using a Chinese multi-institutional registry with Surveillance, Epidemiology, and End Results (SEER) data validation

BACKGROUND

Accumulating evidence has confirmed the potential prognostic value of examined lymph nodes (ELNs) in patients with gastric cancer (GC). However, there is currently no consensus on the threshold ELN number for predicting both stage migration and long-term survival, especially in patients with stage III GC. This study aimed to validate the need to increase the ELN count to improve its prognostic accuracy in node-negative patients with stage III GC after curative gastrectomy.

METHODS

This retrospective, population-based study analyzed the clinical data of 84 patients with node-negative stage III GC from three high-volume institutions in China and 196 cases from the Surveillance, Epidemiology and End Results (SEER) program registry. The optimal number of ELNs was determined by receiver operating characteristic (ROC) curve analysis. Clinicopathological characteristics significantly related to survival were evaluated using the Kaplan-Meier method and Cox proportional hazards analysis. Stratified analyses were adopted to assess the prognostic predictive ability of the identified optimal number of ELNs in different populations. Survival differences among subgroups were analyzed to assess the impact of ELN count on stage migration according to overall survival (OS) among GC patients.

RESULTS

The optimal number of ELNs was >31 according to ROC analysis of patients with node-negative stage III GC who underwent gastrectomy. Multivariate analysis identified ELNs as an independent predictor of postoperative OS in patients with node-negative stage III GC in both the Chinese cohort [hazard ratio (HR) 0.235; P<0.001] and the SEER cohort (HR 0.421; P<0.010). Stratified analysis demonstrated that >31 ELNs was a prerequisite for accurate prognostic evaluation of patients with node-negative stage III GC, regardless of sex, tumor size, and other factors. Stage migration between pT4bN0M0 and pT4bN1M0 was detected in patients with >31 ELNs. A nomogram was created to predict OS among patients with node-negative stage III GC. These results were validated using data from the SEER cohort.

CONCLUSIONS

The number of ELNs was significantly associated with prognosis in patients with stage III GC after gastrectomy with systemic lymphadenectomy in both the Chinese and SEER cohorts. The results suggest that >31 ELNs are required for an accurate prognostic evaluation in patients with GC, especially those with node-negative stage III GC.

Impact of the number of examined lymph nodes on stage migration in node-negative gastric cancer patients: a Chinese multi-institutional analysis with propensity score matching

BACKGROUND

This propensity score matching (PSM) analysis assessed the influence of examined lymph nodes (ELNs) count on stage migration and survival in node-negative (pN0) gastric cancer (GC) patients.

METHODS

We performed a retrospective analysis of 7,620 GC patients who underwent curative gastric resection in three Chinese medical centers. PSM was used to reduce the confounding effects between the pN0 GC patients with ELNs <16 or ≥16. Survival differences among various subgroups of GC patients were analyzed to assess the impact of the ELNs count on the stage migration in accordance with the overall survival (OS) of pN0 GC patients.

RESULTS

After matching, the backgrounds of pN0 GC patients in the ELNs <16 (n=825) and ELNs ≥16 (n=826) groups were well-balanced. Survival analyses revealed that the ELNs count was positively correlated with the OS (P=0.001). Multiple Cox analysis indicated that the ELNs count was an independent predictor of the OS in pN0 GC patients. Stage migrations were mainly detected in subgroups of pN0 GC patients with specific pTNM stages, as follows: (I) pT2N0M0 with ELNs <16 vs. pT3N0M0 with ELNs ≥16; (II) pT3N0M0 with ELNs <16 vs. pT3N1M0 with ELNs ≥16; and (III) pT4aN0M0 with ELNs <16 vs. pT4aN1M0 with ELNs ≥16.

CONCLUSIONS

We show that stage migration can be detected in pN0 GC patients, and that it could be gradually reduced or prevented by increasing the ELNs count.

Laparoscopic versus open approach in gastrectomy for advanced gastric cancer: a systematic review

BACKGROUND

Additional studies comparing laparoscopic gastrectomy (LG) versus open gastrectomy (OG) for advanced gastric cancer (AGC) have been published, and it is necessary to update the systematic review of this subject.

OBJECTIVE

We conducted the meta-analysis to find some proof for the use of LG in AGC and evaluate whether LG is an alternative treatment for AGC.

METHOD

Randomized controlled trials (RCT) and high-quality retrospective studies (NRCT) compared LG and OG for AGC, which were published in English between January 2010 and May 2019, were search in PubMed, Embase, and Web of Knowledge by three authors independently and thoroughly. Some primary endpoints were compared between the two groups, including intraoperative time, intraoperative blood loss, harvested lymph nodes, first flatus, first oral intake, first out of bed, post-operative hospital stay, postoperative morbidity and mortality, rate of disease recurrence, and 5-year over survival (5-y OS). Besides, considering for this 10-year dramatical surgical material development between 2010 and 2019, we furtherly make the same analysis based on recent studies published between 2016 and 2019.

RESULT

Thirty-six studies were enrolled in this systematic review and meta-analysis, including 5714 cases in LAG and 6094 cases in OG. LG showed longer intraoperative time, less intraoperative blood loss, and quicker recovery after operations. The number of harvested lymph nodes, hospital mortality, and tumor recurrence were similar. Postoperative morbidity and 5-y OS favored LG. Furthermore, the systemic analysis of recent studies published between 2016 and 2019 revealed similar result.

CONCLUSION

A positive trend was indicated towards LG. LG can be performed as an alternative to OG for AGC.

Risk factors analysis and stratification for microscopically positive resection margin in gastric cancer patients

Background

Cancer cells are often found postoperatively at surgical resection margins (RM) in patients with gastric cancer because of submucosal infiltration or hesitation to secure adequate RM. This study was designed to evaluate risk factors for microscopic positive RM and to clarify which patients should undergo intraoperative frozen section diagnosis (IFSD).

Methods

Patients who underwent R0/1 gastrectomy for gastric adenocarcinoma between 2000 and 2018 in a single cancer center in Japan were studied. We divided the patients into a positive RM group and negative RM group according to the results of definitive histopathological examinations. We performed multivariate analysis to analyze risk factors for positive RM by and used the identified risk factors to risk stratify the patients.

Results

A total of 2757 patients were studied, including 49 (1.8%) in the positive RM group. The risk factors significantly associated with positive RM were remnant gastric cancer (odds ratio [OR] 4.7), esophageal invasion (OR 6.3), tumor size ≥80 mm (OR 3.9), and a histopathological diagnosis of undifferentiated type (OR 3.6), macroscopic type 4 (OR 3.7), or pT4 disease (OR 4.6). On risk stratification analysis, the incidence of positive RM was 0.1% without any risk factors, increasing to 0.4% with one risk factor, 3.1% with two risk factors, 5.3% with three risk factors, 21.3% with four risk factors, and 85.7% with five risk factors.

Conclusions

The risk of macroscopically positive RM increased in patients who have risk factors. IFSD should be performed in patients who have four or more risk factors.

Small early gastric cancer with synchronous bone metastasis: A case report

Bone metastasis during the early stages of gastric cancer is rare, and synchronous bone metastasis is even less common. The present report outlines a case of a small early gastric cancer, which was detected due to bone metastasis. A 63-year-old man was referred to Fukuyama Medical Center with back pain and anorexia of 2 weeks' evolution. MRI revealed multiple metastatic lesions in the thoracic and spinal bone. Fluorodeoxyglucose positron emission tomography revealed focal uptake in the lesser curvature of the stomach and in the spinal bone, pelvic and thigh bone, but uptake was not detected in the stomach. Esophagogastroduodenoscopy revealed a 10 mm slightly elevated lesion with a central depression in the middle-third of the stomach. Endoscopic ultrasonography confirmed that the tumor was confined to the mucosa. A biopsy specimen acquired from the gastric lesion indicated signet-ring cell carcinoma, and the specimen acquired from the lumbar spine revealed cell aggregation such as that found in signet-ring cell carcinoma. The patient received first-line chemotherapy with S-1 and cisplatin, and second-line chemotherapy with nab-paclitaxel. However, the patient died 120 days after consultation at Fukuyama Medical Center.

Risk factors for stage underestimation in patients with clinical T1N0 gastric cancer

PURPOSE

Limited gastrectomy has been generally performed in clinical T1N0 gastric cancer. The aim of this study was to identify risk factors for stage underestimation in clinical T1N0 gastric cancer.

METHODS

This study reviewed the medical records of 566 patients who underwent gastrectomy for clinical T1N0 gastric cancer.

RESULTS

The tumor stage was underestimated in 122 (21.6%) patients. The relapse-free survival rate was significantly lower in the patients with pathological stage II (P = 0.021) and III (P < 0.001) disease than in those with pathological stage IA disease. In the multivariate analysis, a location in the upper third of the stomach, tumor size of ≥ 30 mm, undifferentiated adenocarcinoma and clinical tumor depth of SM were identified as independent risk factors for pathological stages II and III. The rate of pathological stages II and III was 0% in the patients with no risk factors, 3% in those with 1 risk factor, 10.5% in those with 2 risk factors, 19.8% in those with 3 risk factors and 50% in those with 4 risk factors.

CONCLUSIONS

Location, tumor size, undifferentiated adenocarcinoma and clinical tumor depth were independent risk factors for pathological stages II and III in clinical T1N0 gastric cancer.

Negative lymph node count as an independent prognostic factor in stage III patients after curative gastrectomy: A retrospective cohort study based on a multicenter database

OBJECTIVE

To examine the prognostic value of negative lymph node (NLN) count in stage III gastric cancer (GC) patients after curative gastrectomy.

METHODS

The clinicopathological data of 2942 stage III patients who underwent curative gastrectomy between 2001 and 2011 were analyzed. Only patients with ≥16 examined lymph nodes (ELNs) were included. After cut-point survival analysis, the 2942 patients were divided into three subgroups with NLN counts of 0, 1-9, and ≥10. Survival differences among the subgroups were analyzed to assess the effects of NLN count on stage migration and overall survival (OS) in stage III GC patients. Spearman's correlation coefficient was used to assess the relationships between the ELN count and the positive lymph node (PLN) count, the ELN count and the NLN count, and the NLN count and the PLN count.

RESULTS

Survival analyses revealed that the NLN count was significantly associated with OS (P = 0.001) and was an independent predictor (P < 0.01) of prognosis in stage III GC patients. Subgroup analysis showed that the prognostic evaluation accuracy was highest when the NLN count was ≥10 for stage III patients. Stage migrations were mainly detected in the following pathological tumor-node (pTN) subgroups: pT2N3a with 1-9 NLNs and pT2N3b with ≥10 NLNs, and pT3N3a with 1-9 NLNs and pT3N3b with ≥10 NLNs. NLN count was positively correlated with the ELN and the PLN counts for pT2N3 and pT3N3 stage GC patients (r = 0.694 and r = 0.881 for pT2N3 patients; r = 0.685 and r = 0.902 for pT3N3 patients, respectively; P < 0.001). These findings indicate that the NLN count may be a useful prognostic predictor in stage III GC patients.

CONCLUSIONS

The NLN count may improve the prognostic prediction efficiency of the tumor-node-metastasis (TNM) classification for GC, especially for stage III patients, and should be recommended for clinical applications.

Insufficient examined lymph node count underestimates staging in pN3a patients after curative gastrectomy: a multicenter study with external validation

PURPOSE

The present study aims to validate possible stage migration of lymph node metastasis related to the insufficient examined lymph node (ELN) count in pN3a gastric cancer (GC) patients.

METHODS

1976 pN3 patients who underwent the R0 surgery in three high-capacity institutions in China were enrolled to explore the stage migration of nodal involvement, and 3146 pN3 cases from the Surveillance, Epidemiology, and End Results (SEER) Program Registry were used as an external validation cohort.

RESULTS

After the propensity score matching of the Chinese cohort, the ELN count, as an independent predictor for GC outcome, was confirmed to be associated with the stage migration of lymph node metastasis in pN3a patients based on the univariate and multivariate survival analyses. Logistic regress was adopted to elucidate that the ELN count was an independent factor related to the long-term survival status of GC patients after curative surgery. Likelihood ratio test showed that the ELN count had the smallest Bayesian information criterion value among the clinicopathologic variables, corresponding to an efficient model to predict outcomes. Subsequently, stage migration of lymph node metastasis was predominantly detected in pN3a patient sub-group with insufficient (less than 16) ELN count, who presented with similar prognosis as the pN3b patients (P = 0.463) as per the stratum analysis with Kaplan-Meier. These methods were further validated using data from the SEER cohort, and the similar promising results were obtained.

CONCLUSION

pN3a patients with insufficient ELN count should be considered as pN3b cases to achieve accurate prognostic evaluation after curative gastrectomy.

Prognostic impact of D2-plus lymphadenectomy and optimal extent of lymphadenectomy in advanced gastric antral carcinoma: Propensity score matching analysis

OBJECTIVE

To investigate the prognostic impact of D2-plus lymphadenectomy including the posterior (No. 8p, No. 12b/p, No. 13, and No. 14v), and para-aortic (No. 16a2, and No. 16b1) lymph nodes (LNs) in subtotal gastrectomy for advanced gastric antral carcinoma.

METHODS

A total of 203 patients with advanced gastric cancer (GC) located in the antrum, who underwent R0 gastrectomy with D2 or D2-plus lymphadenectomy between January 2003 and December 2011 were enrolled. Propensity score matching was used to reduce the strength of the confounding factors to accurately evaluate prognoses. The therapeutic value index (TVI) was calculate to evaluate the survival benefit of dissecting each LN station.

RESULTS

Of 102 patients with D2-plus lymphadenectomy, 21 (20.59%) were pathologically identified as having LN metastases beyond the extent of D2 lymphadenectomy. After matching, the overall survival (OS) was significantly better in the D2-plus than the D2 group (P=0.030). In the multivariate survival analysis, D2-plus lymphadenectomy (hazard ratio, 0.516; P=0.006) was confirmed to significantly improve the survival rate. In the logistic regression analysis, pN stage [odds ratio (OR), 2.533; 95% confidence interval (95% CI), 1.368-4.691; P=0.003] and extent of LNs metastasis (OR, 5.965; 95% CI, 1.335-26.650; P=0.019) were identified as independent risk factors for LN metastases beyond the extent of D2 lymphadenectomy. The TVI of patient with metastasis to LNs station was 7.1 (No. 8p), 5.7 (No. 12p), 5.1 (No. 13), and 7.1 (both No. 16a2 and No. 16b1), respectively.

CONCLUSIONS

D2-plus lymphadenectomy may improve the prognoses of some patients with advanced GC located in the antrum, especially for No. 8p, No. 12b, No. 13, and No. 16.

Progress in the treatment of gastric cancer in Japan over the last 50 years

There have been remarkable changes in gastric cancer treatments in Japan, resulting in superb improvement of prognosis in patients with this disease. In this paper, the last 50 years have been divided into three eras: before 1990; the 1990s; and the era of evidence, which means after 2000. Changes of treatments and prognosis were analyzed by several factors, such as surgery, chemotherapy, informed consent, clinical trials, and others, as improvement of prognosis is not due to one factor but several ones influencing each other.

Long Noncoding RNA UCA1 Regulates PRL-3 Expression by Sponging MicroRNA-495 to Promote the Progression of Gastric Cancer

Gastric cancer (GC) is among the most frequently occurring malignancies worldwide. In recent years, long noncoding RNAs (lncRNAs) have been widely studied because of their ability to regulate the cellular processes involved with tumorigenesis. The present study aims to investigate the underlying molecular mechanism by which lncRNA urothelial carcinoma-associated 1 (UCA1) influences the progression of GC. Differentially expressed lncRNA UCA1 was initially identified by microarray-based analysis, after which a high expression of UCA1 was determined in GC tissues and cells. It is important to note that UCA1 could upregulate the expression of phosphatase of regenerating liver-3 (PRL-3) by sponging miR-495. The expression of UCA1 and miR-495 was altered in human GC cells to evaluate cell activity in vitro, as well as peritoneal metastasis and tumor formation ability in vivo. Results suggested that increased expression of UCA1 promoted cell proliferation, migration, and invasion, accompanied by suppressed cell apoptosis, as well as enhanced peritoneal metastasis and tumorigenesis of GC cells. Meanwhile, the upregulated expression of miR-495 could reverse the promotive effects exerted by UCA1. Taken conjointly, UCA1, as a competing endogenous RNA (ceRNA) of miR-495, could accelerate the development of GC by upregulating PRL-3, highlighting a potentially promising basis for the targeted intervention treatment of GC.

Impact of the Age-adjusted Charlson comorbidity index on the short- and long-term outcomes of patients undergoing curative gastrectomy for gastric cancer

Background: The aim of this study was to determine whether or not the short- and long-term outcomes were affected by the age-adjusted Charlson comorbidity index (ACCI) in patients who underwent curative resection for gastric cancer.

Methods: The patients were retrospectively selected from among the medical records of consecutive patients who underwent curative gastrectomy with nodal dissection for gastric cancer at Yokohama City University and Kanagawa Cancer Center from January 2000 to August 2015.

Results: A total of 2254 patients were eligible for inclusion in the present study. One thousand six hundred fifty-six patients had an ACCI of <6 points (ACCI low group), while 598 had a score of ≥6 points (ACCI high group). The median age (p<0.001) and American Society of Anesthesiologists physical status (ASA-PS) score (p<0.001) of the ACCI high group were higher in comparison to the ACCI low group. The incidence of surgical complications in the ACCI high group was significantly higher than that in the ACCI low group (12.0% vs. 7.2%, p<0.001). Univariate and multivariate analyses demonstrated that an ACCI high classification was a significant risk factor for postoperative complications. In addition, the 5-year OS rates of the ACCI low and ACCI high groups were 85.4% and 74.1%, respectively. The difference was statistically significant (p<0.001). The univariate and multivariate analyses demonstrated that an ACCI high classification was a significant prognostic factor for OS.

Conclusions: Our results support that a high ACCI value is an independent risk factor for the short- and long-term outcomes of patients with gastric cancer. To improve the survival of patients with gastric cancer, it is necessary to carefully plan the perioperative care and the surgical strategy according to the ACCI.

Laparoscopy Assisted Distal Gastrectomy Versus Open Distal Gastrectomy for Patients with Gastric Cancer in A Middle Resources Country

Background:Laparoscopic surgery with a small laparotomy has several advantages over conventional open surgery, including less invasiveness, less pain, earlier recovery, and better cosmoses. The aim of this study was to compare technical feasibility and early clinical outcomes of laparoscopy-assisted distal gastrectomy in comparison with open distal gastrectomy for gastric cancer in a developing country. Patients and methods :In this retrospective study, patients with distal gastric cancer were divided into two groups (a) patients underwent laparoscopy assisted distal gastrectomy (LADG) (21 patients) and (b) open distal gastrectomy (ODG) (21 patients). For the postoperative pathologic results, the tumor-nodal-metastasis (TNM) stage, grade of tumor differentiation, distal and proximal margins, the number of harvested lymph nodes were evaluated. Staging was done according to the 7th edition of the UICC tumor, node, and metastasis (TNM) classification. D1/D2 lymphadenectomy with curative R0 intention was attempted in all cases. Perioperative mortality and morbidity were assessed. Results:The time to initiate oral intake, and postoperative hospital stay were significantly shorter in the LADG group than in the ODG group (P < 0.001). The operative time in the LADG group was significantly less than that of the ODG group (P = 0.05). Blood loss and blood transfusion frequency were significantly lower (P < 0.0001) in the LADG group in comparison to ODG group. Conclusion:Laparoscopic-assisted distal gastrectomy for distal gastric cancer could be safe and feasible technique alternative to open gastrectomy in a middle income country, with at least similar short term surgical and oncological results. However, laparoscopic gastric surgery is in need to adequate training and technical support especially in D2 lymphadenectomy.

Clinical significance of skip lymph-node metastasis in pN1 gastric-cancer patients after curative surgery

BACKGROUND

In addition to the stepwise manner of lymph-node metastasis from the primary tumour, the skip lymph-node metastasis (SLNM) was identified as a low-incidence metastasis of gastric cancer (GC). So far, both the mechanism and outcome of SLNM have not been elucidated completely. The purpose of this study was to analyse the clinical significance and the potential mechanism of SLNM in GC patients who had lymph-node metastasis.

METHODS

Clinicopathological data and follow-up information of 505 GC patients who had lymph-node metastasis were analysed to demonstrate the significance of SLNM in evaluating the prognostic outcome. According to the pathological results, all GC patients who had lymph-node metastasis were categorized into three groups: patients with the perigastric lymph-node metastasis, patients with the perigastric and extragastric lymph-node metastasis and patients with SLNM.Results: Among the 505 GC patients who had lymph-node metastasis, 24 (4.8%) had pathologically identified SLNM. The location of lymph-node metastasis was not significantly associated with 5-year survival rate and overall survival (OS) (P = 0.194). The stratified survival analysis results showed that the status of SLNM was significantly associated with the OS in patients with pN1 GC (P = 0.001). The median OS was significantly shorter in 19 pN1 GC patients with SLNM than in 100 patients with perigastric lymph-node metastasis (P < 0.001). The case-control matched logistic regression analysis results showed that tumour size (P = 0.002) was the only clinicopathological factor that may predict SLNM in pN1 GC patients undergoing curative surgery. Among the 19 pN1 GC patients with SLNM, 17 (89.5%) had metastatic lymph nodes along the common hepatic artery, around the celiac artery or in the hepatoduodenal ligament.

CONCLUSIONS

SLNM may be considered a potentially practicable indicator for prognosis among various subgroups of pN1 GC patients.

Is curative gastrectomy justified for gastric cancer with cytology positive as the only stage IV factor?

AIMS

The prognosis of patients with gastric cancer and stage IV factors is poor. However, several recent studies have identified that curative surgery followed by S-1 chemotherapy for cytology positive (CY1) only patients contributed to a better prognosis. This study was designed to compare the prognosis between curative and palliative gastrectomy followed by chemotherapy in CY1 only stage IV gastric cancer.

METHODS

Between 2001 and 2016, 1507 patients underwent gastrectomy for gastric cancer. Of these, 51 consecutive patients with only CY1 factor who underwent gastrectomy followed by chemotherapy were enrolled in this study.

RESULTS

(1) Twenty three (45%) patients underwent curative D2 or D2+ gastrectomy, and the remaining 28 (55%) patients underwent palliative gastrectomy, followed by S-1 based or another historical recommended chemotherapy postoperatively. (2) Compared with patients undergoing palliative gastrectomy, patients undergoing curative gastrectomy had a significantly better prognosis (P = 0.042; median survival time: curative vs. palliative, 22.6 months vs. 11.8 months) and a lower incidence of recurrences (P = 0.091). Two- and five-year overall survival rates of patients following curative gastrectomy were 48.2% and 18.2%, respectively. A multivariate analysis showed that venous invasion [P = 0.006; hazard ratio (HR), 3.70 (95% CI: 1.27-9.43)] and curative gastrectomy [P < 0.005; HR, 0.28 (95% CI: 0.12-0.87)] were independent prognostic factors.

CONCLUSION

Curative gastrectomy followed by chemotherapy might be justified to improve the prognosis of patients with only CY1 Stage IV gastric cancer.

Nutritional safety of oncometabolic surgery for early gastric cancer patients: a prospective single-arm pilot study using a historical control group for comparison

BACKGROUND

Oncometabolic surgery (OS) is a modification of the Roux-en Y reconstruction method, in which the lengths of the biliopancreatic and Roux limbs are longer than that with conventional surgery (CS). Although OS is performed to improve postoperative glycemic control in gastric cancer patients with type 2 diabetes mellitus (T2DM), its postoperative nutritional safety has not been clarified. This prospective pilot study evaluated the safety and feasibility of OS in early gastric cancer patients.

METHODS

This study evaluated 20 patients with clinical T1N0 stage and preoperative body mass index (BMI) ≥ 32.5 kg/m², or ≥ 27.5 kg/m² with comorbidities, who underwent OS. Primary outcomes were cumulative incidences of anemia and deficiencies in iron and vitamin B12 after 1 year. The outcomes were compared to those of a matched historical control group.

RESULTS

The cumulative incidences of anemia (15.0% vs. 10.0%, P = 0.99), iron deficiency (15.0% vs. 10.0%, P = 0.99), and vitamin B12 deficiency (10.0% vs. 0%, P = 0.47) did not differ significantly in the OS and CS groups. However, median vitamin B12 concentration tended to be lower (395.8 vs. 493.7 pg/mL, P = 0.06) and reductions in vitamin B12 concentration tended to be greater (174.7 vs. 123.0 pg/mL, P = 0.07) in the OS group. BMI loss was similar in the two groups (2.9 vs. 2.8 kg/m², P = 0.80). Remission rates of hypertension (68.8% vs. 41.2%, P = 0.22) and T2DM (77.8% vs. 50.0%, P = 0.58) were higher in the OS group.

CONCLUSION

Nutritional parameters did not differ significantly in the OS and CS groups. Vitamin B12 levels should be carefully monitored after OS.

The prognostic value of a Surgical Outcome Risk Tool in patients after radical gastrectomy for gastric cancer and its guiding significance for postoperative chemotherapy

OBJECTIVE

To provide individualized survival predictors for patients after radical gastrectomy and to guide adjuvant treatment.

METHODS

The data of patients with gastric cancer treated in our department from January 1996 to December 2014 were analyzed retrospectively. A Surgical Outcome Risk Tool (SORT) was used to indicate the physical condition of the patients.

RESULTS

A total of 5327 patients in the study. The 5-year overall survival rates in the low-, moderate- and high-risk group were 61.6%, 54.7% and 44.4%, respectively (p < 0.001). A multivariate analysis showed that SORT was an independent prognostic factor for gastric cancer. There was significant chemotherapy benefit after surgery in stage II-III patients with a SORT<3 and in stage III patients with a SORT≥3 (p < 0.05). However, chemotherapy did not improve the 5-year overall survival in stage II patients with a SORT≥3 (62.4% vs. 48.3%, p = 0.196). The calculated difference between two nomogram models was the potential benefit of adjuvant chemotherapy for patients with gastric cancer.

CONCLUSION

A SORT is an independent risk factor for predicting the prognosis of gastric cancer, and postoperative adjuvant chemotherapy should be carefully adopted in stage II patients with a SORT≥3.

Long-term outcomes of laparoscopy-assisted distal gastrectomy versus open distal gastrectomy for gastric cancer: a 10-year single-institution experience

BACKGROUND

Laparoscopy-assisted distal gastrectomy (LADG) for gastric cancer has been widely applied; however, its oncologic efficacy has yet been well established. The study aimed to compare the long-term oncologic outcomes of LADG versus open distal gastrectomy (ODG) on gastric cancer.

METHODS

The clinicopathologic data of gastric cancer patients who underwent distal gastrectomy with curative intent from October 2004 through September 2014 were included and analyzed in a retrospective cohort. The last follow-up was September 2016.

RESULTS

769 eligible patients (LADG 414 vs. ODG 355) were included in the study. No significant difference was observed between the groups in 5-year DFS (LADG 61.2% vs. ODG 59.1%; p = 0.384) and OS rates (LADG 65.8% vs. ODG 66.3%; p = 0.750). During surgery, though LADG group had longer operating time, the blood loss was less than ODG group. LADG group had faster postoperative recovery course including shorter time to oral intake, ambulation, and discharge time. Postoperative complication rate within 30 days showed no significant difference between the groups (LADG 15.7% vs. ODG 13.0%; p = 0.281). Age over 65 years old, blood loss > 200 ml, postoperative complication, and advanced T and N stage were identified as independent risk factors for DFS and OS.

CONCLUSIONS

LADG could yield similar oncologic outcomes compared with ODG in treating distal gastric cancer. However, the findings need to be further confirmed through ongoing prospective randomized controlled trials.

Robotic-assisted gastrectomy for gastric cancer: a European perspective

Gastrectomy is the mainstay treatment for gastric cancer. To reduce the associated patient burden, minimally invasive gastrectomy was introduced in almost 30 years ago. The increase in the availability of surgical robotic systems led to the first robotic-assisted gastrectomy to be performed in 2002 in Japan. Robotic gastrectomy however, particularly in Europe, has not yet gained significant traction. Most reports to date are from Asia, predominantly containing observational studies. These cohorts are commonly different in the tumour stage, location (particularly with regards to gastroesophageal junctional tumours) and patient BMI compared to those encountered in Europe. To date, no randomised clinical trials have been performed comparing robotic gastrectomy to either laparoscopic or open equivalent. Cohort studies show that robotic gastrectomy is equal oncological outcomes in terms of survival and lymph node yield. Operative times in the robotic group are consistently longer compared to laparoscopic or open gastrectomy, although evidence is emerging that resectional surgical time is equal. The only reproducibly significant difference in favour of robot-assisted gastrectomy is a reduction in intra-operative blood loss and some studies show a reduction in the risk of pancreatic fistula formation.

Evaluation of Gastric Carcinomas Histological Patterns in Relation to Tumors Aggressiveness Parameters

Gastric carcinomas are frequent tumors with variable growth patterns that may interfere with the evaluation of histopathological prognostic parameters of the lesions. In this study we analyzed the incidence and statistical relation of histological growth patterns depending on the prognostic parameters of gastric carcinomas for 95 cases. Pure forms were present in 82.2% of cases, from which more frequent subtypes were low grade tubular carcinomas and poorly cohesive with signet-ring cells carcinomas. Mixed forms were present in 17.8% of cases, with the highest incidence of tumors containing well differentiated tubular carcinoma and poorly differentiated papillary carcinoma areas. Analysis of the identified types and subtypes in relation to the histological prognostic parameters indicated significant differences regarding the tumor stage, the mixed subtypes being more frequent in advanced stages. Although mixed subtypes were more commonly associated with vascular and perineural invasion, the aspects were statistically insignificant. Together with tumor stage, the lymphovascular and/or perineural invasion should be taken into consideration as prognostic indicators in the postoperative management of gastric cancer.

Comprehensive Complication Index Predicts Cancer-Specific Survival of Patients with Postoperative Complications after Curative Resection of Gastric Cancer

OBJECTIVE

To investigate the prognostic impact of postoperative complications for patients with gastric cancer.

METHODS

Postoperative complications of patients undergoing radical gastrectomy for gastric cancer were reviewed. The severity of complications was graded by the CCI and C-D classification.

RESULTS

A total of 5327 patients were included in the study. Complications were observed in 767 patients. When the C-D classification system was applied, for patients with grade I-II complications, the length of stay (LOS) of those with high CCI (CCI ≥ 26.2) was significantly longer than that of patients with low CCI (CCI < 26.2) (p < 0.001). The 5-year cancer-specific survival rate of patients with complications (52%) was lower than that of patients without complications (61%) (p < 0.001). Analysis of the factors associated with prognosis in patients with gastric cancer revealed that complications were independent risk factors for specific survival. When CCI was used to classify complication severity, the 5-year cancer-specific survival rate of the high-CCI group was 46.3%, which was lower than that of the low-CCI group (54.9%, p = 0.009).

CONCLUSION

Complication after radical gastrectomy is an independent prognostic factor, and the complication severity as graded by CCI reflects the difference of cancer-specific survival in gastric cancer patients with postoperative complications.

Validation of clinical significance of examined lymph node count for accurate prognostic evaluation of gastric cancer for the eighth edition of the American Joint Committee on Cancer (AJCC) TNM staging system

OBJECTIVE

To validate the necessity of increasing the examined lymph node (ELN) count for enhancing the accuracy of prognostic evaluation of gastric cancer (GC) patients after curative gastrectomy in multiple medical centers of China.

METHODS

The clinicopathological data of 7,620 patients who underwent the curative resection for GC between 2001 and 2011 were included to demonstrate whether the ELN count is indispensable for enhancing the accuracy of prognostic evaluation of GC patients after surgery. After a meticulous stratification by using the cut-point survival analysis, all included 7,620 patients were allocated into three groups as: less than 16 (<16), between 16 and 30 (16-30), and more than 30 (>30) ELNs. Survival differences among various subgroups of GC patients were analyzed to assess the impact of the ELN count on the stage migration in accordance with the overall survival (OS) of GC patients.

RESULTS

Survival analyses revealed that the ELN count was positively correlated with the OS (P=0.001) and was an independent prognostic predictor (P<0.01) of 7,620 GC patients. Stratum analysis showed that the accuracy of prognostic evaluation could be enhanced when the ELN count was no less than 16 (≥16) for node-negative patients and >30 for node-positive patients. Stage migrations were mainly detected in the various subgroups of patients with specific pN stages as follows: pN0 with 16-30 ELNs (pN016-30) and pN0 with >30 ELNs (pN0 >30), pN0 with <16 ELNs (pN0 <16) and pN1>30, pN1<16 and pN216-30, pN116-30 and pN2>30, pN3a<16 and pN3b16-30, and pN3a<16 and pN3b>30. These findings indicate that increasing the ELN count is a prerequisite to guarantee precisely prognostic evaluation of GC patients.

CONCLUSIONS

The ELN count should be proposed to be >30 for acquiring the accurate prognostic evaluation for GC patients, especially for node-positive patients.

Diagnostic accuracy of T stage of gastric cancer from the view point of application of laparoscopic proximal gastrectomy

The preoperative diagnosis of T stage is important in selecting limited treatments, such as laparoscopic proximal gastrectomy (LPG), which lacks the ability to palpate the tumor. Therefore, the present study examined the accuracy of preoperative diagnosis of the depth of tumor invasion in early gastric cancer from the view point of the indication for LPG. A total of 193 patients with cT1 gastric cancer underwent LPG with gastrointestinal endoscopic examinations and a series of upper gastrointestinal radiographs. The patients with pT1 were classified into the correctly diagnosed group (163 patients, 84.5%), and those with pT2 or deeper were classified into the underestimated group (30 patients, 15.5%). Factors that were associated with underestimation of tumor depth were analyzed. Tumor size in the underestimated group was significantly larger; the lesions were more frequently located in the upper third of the stomach and were more histologically diffuse, scirrhous, with infiltrative growth, and more frequent lymphatic and venous invasion. For upper third lesions, in univariate analysis, histology (diffuse type) was associated with underestimation of tumor depth. Multivariate analysis found that tumor size (≥20 mm) and histology (diffuse type) were independently associated with underestimation of tumor depth. gastric cancer in the upper third of the stomach with diffuse type histology and >20 mm needs particular attention when considering the application of LPG.