R0 resection in the treatment of gastric cancer: Room for improvement

Role of Preoperative Radiation Therapy for Resectable Gastric Cancer

PURPOSE

While surgery is the primary curative treatment for resectable gastric and gastroesophageal junction (GEJ) cancer, rates of locoregional and distant recurrence remain high with surgery alone, especially in more advanced disease. Multimodal approaches with perioperative therapy including chemotherapy and/or radiation therapy (RT) have thus evolved as ways to reduce the rates of disease recurrence and improve survival outcomes. This review article provides a comprehensive literature review on the role of preoperative RT for resectable gastric and GEJ cancer.

METHODS

A literature review on the role of preoperative RT for resectable gastric and GEJ cancer was conducted.

RESULTS

Preoperative RT has the potential to facilitate tumor downstaging and improved R0 resection, allowing for better locoregional control and thereby survival. For resectable locally advanced GEJ cancer, preoperative chemoradiotherapy (CRT) is currently a standard of care option along with perioperative chemotherapy, based on evidence from randomized trials. In resectable gastric cancer, however, the role of preoperative CRT is less defined with no randomized data to date, although phase II single-arm studies have shown promising results. Current standard of care for gastric cancer remains perioperative chemotherapy, with consideration for preoperative CRT in select cases.

CONCLUSION

Results from ongoing and future randomized controlled trials are expected to help define the role of preoperative CRT compared to perioperative chemotherapy alone as well as postoperative CRT for gastric and GEJ cancer.

Assessing the benefits of repeated esophagogastroduodenoscopy at a specialized center before gastric and esophageal cancer surgery

BACKGROUND

The surgical treatment of gastric and esophageal cancer in Denmark is centralized in four specialized esophagogastric cancer (EGC) centers. Patients are referred after an esophagogastroduodenoscopy (EGD) at a secondary healthcare facility. The EGD is repeated at the specialized EGC center before determining a surgical treatment strategy. This multicenter retrospective study aimed to investigate the quality of EGDs performed at a secondary healthcare facility and evaluate the clinical value of repeated EGD at a specialized center when determining the surgical treatment strategy.

METHODS

Patients from three of the four centers, who underwent esophagectomy or gastrectomy with curative intent from 1 June 2016 to 1 May 2021, were included. EGD reports from the referral facilities and EGC centers were compared based on a predefined checklist. Furthermore, endoscopist experience, the time between examinations, and histology were registered. Finally, it was assessed whether the specialized EGD led to any substantial changes in surgical treatment. Baseline characteristics and differences in EGD reports were described and McNemar's chi-square test was performed. A logistic regression analysis was conducted to identify risk factors for a change in surgical strategy.

RESULTS

The study included 953 patients who underwent both an initial EGD and EGD at referral to a specialized center. In 644 cases (68%), the information from the initial EGD was considered insufficient concerning preoperative tumor information. In 113 (12%) cases, the findings in the specialized EGD would lead to a significant alteration in the surgical strategy compared with the primary EGD.

CONCLUSION

The findings suggest that repeated EGD at a specialized center is of clinical value and helps ensure proper surgical treatment for patients undergoing curative surgery for gastroesophageal cancer.

Analysis of Patient Outcomes following Curative R0 Multiorgan Resections for Locally Advanced Gastric Cancer: A Systematic Review and Meta-Analysis

Background: This systematic review examines the efficacy of multiorgan resection (MOR) in treating locally advanced gastric cancer (LAGC), focusing on survival outcomes, postoperative morbidity, and mortality. Methods: We conducted a comprehensive search of studies in PubMed, Scopus, and Embase up to November 2023, based on the PRISMA guidelines. The inclusion criteria focused on clinical trials, observational studies, case-control studies, and qualitative research, involving patients of any age and gender diagnosed with LAGC undergoing MOR aimed at R0 resection, with secondary outcomes focusing on survival rates, postoperative outcomes, and the effects of adjuvant and neoadjuvant therapies. Exclusion criteria ruled out non-human studies, research not specifically focused on LAGC patients undergoing MOR, and studies lacking clear, quantifiable outcomes. The quality assessment was performed using the Newcastle-Ottawa Scale. The final analysis included twenty studies, involving a total of 2489 patients across a time span from 2001 to 2023. Results highlighted a significant variation in median survival times ranging from 10 to 27 months and R0 resection rates from 32.1% to 94.3%. Survival rates one-year post-R0 resection varied between 46.7% and 84.8%, with an adjusted weighted mean of 66.95%. Key predictors of reduced survival included esophageal invasion and peritoneal dissemination, the presence of more than six lymph nodes, and tumor sizes over 10 cm. Nevertheless, the meta-analysis revealed a significant heterogeneity (I2 = 87%), indicating substantial variability across studies, that might be caused by differences in surgical techniques, patient demographics, and treatment settings which influence survival outcomes. Results: The review underlines the important role of achieving R0 resection status in improving survival outcomes, despite the high risks associated with MOR. Variability across studies suggests that local practice patterns and patient demographics significantly influence results. Conclusions: The findings emphasize the need for aggressive surgical strategies to improve survival in LAGC treatment, highlighting the importance of achieving curative resection despite inherent challenges.

Clinical Efficacy and Safety of Endoscopic Treatment of Gastrointestinal Stromal Tumors in the Stomach

Background/Aims

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the stomach. We evaluated the clinical outcomes of endoscopic treatment for gastric GISTs.

Methods

This is a single center, retrospective study that enrolled 135 cases of gastric subepithelial tumors (SETs) resected by endoscopic procedures and confirmed as GISTs by histopathology from March 2005 to July 2019. The immediate and long-term clinical outcomes were analyzed retrospectively.

Results

The mean patient age was 57.9 years, and the mean tumor size was 2.1 cm. Of the tumors, 43.0% were located in the body, followed by the fundus (26.7%) and cardia (17.0%). Most tumors (85.2%) were resected by endoscopic submucosal dissection, followed by endoscopic mucosal resection (6.7%), submucosal tunneling endoscopic resection (5.9%), and endoscopic full-thickness resection (2.2%). Macroperforation occurred in 4.4% and microperforation in 6.7% of the cases. The R0 resection rate was 15.6%. However, the rate of complete resection by the endoscopic view was 90.4%, of which 54.8% of cases were in the very-low-risk group, followed by the low-risk group (28.1%), intermediate-risk group (11.9%), and high-risk group (5.2%). During 36.5 months of follow-up, recurrence was found in four (3.4%) of the 118 patients who were monitored for more than 6 months (low-risk group, 1/37 [2.7%]; intermediate-risk group, 2/11 [18.2%]; high-risk group, 1/6 [16.7%]).

Conclusions

Endoscopic treatment of a GIST appears to be a feasible procedure in selected cases. However, additional surgery should be considered if the pathologic results correspond to intermediate- or high-risk groups.

Systematic review and meta-analysis of the outcomes following neoadjuvant therapy in upfront resectable gastric cancers compared to surgery alone in phase III randomised controlled trials

BACKGROUND

Gastric cancer is the fifth most common malignancy and the fourth most common cause of cancer mortality globally. The role of neoadjuvant chemotherapy in upfront resectable gastric cancer is a subject of ongoing research. In recent meta-analyses, R0 resection rate and superior outcomes were not consistently observed in such regimens.

AIM

To describe the outcomes following phase III randomised control trials; comparing neoadjuvant therapy followed by surgery against upfront surgery with and without adjuvant therapy in resectable gastric cancers.

METHODS

The Cochrane Library, CINAHL, EMBASE, PubMed, SCOPUS and Web of Science was searched from January 2002 to September 2022.

RESULTS

13 studies were included (3280 participants). R0 resection rates were in neoadjuvant therapy arms as compared to adjuvant therapy with odds ratio (OR) 1.55[95% CI: 1.13, 2.13](p=0.007) and compared to surgery alone OR 2.49[95% CI: 1.56, 3.96](p=0.0001). 3-year and 5-year progression-, event- and disease-free survival in neoadjuvant therapy as compared to adjuvant therapy were not significantly increased, 3-year OR 0.87[0.71, 1.07](p=0.19). Meanwhile, comparing neoadjuvant therapy to adjuvant therapy, 3-year overall survival (OS) hazard ratio was 0.88[95% CI: 0.70, 1.11](p=0.71) while 3- and 5-year OS OR was 1.18[95% CI: 0.90, 1.55], p=0.22 and 1.27[95% CI: 0.67, 2.42](p=0.47) respectively. Surgical complications were also more common with neoadjuvant therapy.

CONCLUSION

Neoadjuvant therapy yields higher rates of R0 resection. However, improved long-term survival was not seen as compared to adjuvant therapy. Large multi-centred randomised control trials with D2 lymphadenectomy should be performed to better evaluate the treatment modalities.

Extended Lymphadenectomy for Gastric Cancer in the Neoadjuvant Era: Current Status, Clinical Implications and Contentious Issues

Despite its decreasing incidence, gastric cancer remains an important global healthcare problem due to its overall high prevalence and high mortality rate. Since the MAGIC and FNLCC/FFCD trials, the neoadjuvant chemotherapy has been recommended throughout Europe in gastric cancer. Potential benefits of preoperative treatments include a higher rate of R0 resection achieved by downstaging the primary tumor, a likely effect on micrometastases and isolated tumor cells in the lymph nodes, and, as a result, improved cancer-related survival. Nevertheless, distortion of anatomical planes of dissection, interstitial fibrosis, and sclerotic tissue changes may increase surgical difficulty. The collection of at least twenty-five lymph nodes after neoadjuvant therapy would seem to ensure removal of undetectable node metastasis and reduce the likelihood of locoregional recurrence. It is not what you take but what you leave behind that defines survival. Therefore, para-aortic lymph node dissection is safe and effective after neoadjuvant chemotherapy, in both therapeutic and prophylactic settings. In this review, the efficacy of adequate lymph node dissection, also in a neoadjuvant setting, has been investigated in the key studies conducted to date on the topic.

Gastrectomy for Cancer: A 15-Year Analysis of Real-World Data from the University of Athens

Background and Objectives: Encouraging data have been reported from referral centers following gastrointestinal cancer surgery. Our goal was to retrospectively review patient outcomes following gastrectomy for gastric or gastroesophageal junction (GEJ) cancer at a high-volume unit of the University of Athens. Methods: The enrollment period was from June 2003 to September 2018. Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Cox proportional hazard models were constructed to identify variables independently associated with time-to-event outcomes. Results: A total of 205 patients were analyzed. R0 resection was achieved in 183 (89.3%) patients and was more likely to occur following neoadjuvant chemotherapy (p = 0.008). Recurrence developed in 46.6% of our cohort and the median disease-free survival was 31.2 months. On multivariate analysis, only staging (HR = 2.15; 95% CI: 1.06-4.36) was independently associated with increased risk of recurrence. All-cause mortality was 57.2% and the median time of death was 40.9 months. On multivariate regression, staging (HR: 1.35; 95% CI: 1.11-1.65) and recurrence (HR: 2.87; 95% CI: 1.32-6.22) predicted inferior prognosis. Conclusions: Gastrectomy at the University of Athens has yielded favorable outcomes for patients with GEJ cancer.

A comparison of neoadjuvant therapies for gastroesophageal and gastric cancer on tumour resection rate: A network meta-analysis

Background

Gastric cancer is one of the most common malignancies around the world, and a variety of neoadjuvant chemotherapies with different drug combinations are available for the treatment. R0 resection refers to a microscopically negative margin on resection, where no gross or microscopic tumour remains in the primary tumour. We aimed to find evidence on the relative effectiveness of neoadjuvant therapies for patients with advanced gastroesophageal and gastric cancer on the R0 resection rate.

Methods

Relevant randomised controlled trials were searched using appropriate keywords in health-related databases. We performed network meta-analysis within a frequentist framework. The endpoint assessed was the R0 resection rate. We assessed consistency and transitivity assumptions that are necessary for network meta-analysis. This study only used data from published studies. The need for consent from participants was waived by the Ethics Review Committee of the International Medical University in Malaysia.

Results

Six randomised controlled trials involving 1700 patients were identified. A network plot was formed with five neoadjuvant regimens [DLX (pyrimidine analogue + platinum compounds + chemoradiotherapy), DELX (pyrimidine analogue + epipodophylllotoxins/etoposide + platinum compounds + chemoradiotherapy), ADL (anthracycline + pyrimidine analogue + platinum compounds), ADM (anthracycline+ pyrimidine analogue + anti-folate compounds) and LTX (platinum compounds + taxane + chemoradiotherapy)] and surgery alone for management of patients with advanced gastroesophageal and gastric cancer. Assumptions required for a network meta-analysis such as consistency ((global test: Chi2 (1): 3.71; p:0.054)), and the transitivity in accord to the characteristics of interventions considered in this review were not violated. In the network comparison, surgery alone has a lower R0 resection rate compared with LTX (OR 0.2, 95%CI:0.01, 0.38) or DLX (OR 0.48, 95%CI: 0.29, 0.79). LTX has higher resection rate compared with DLX (OR 2.47, 95%CI: 1.08 to 5.63), DELX (OR 106.0, 95%CI: 25.29 to 444.21), ADM (OR 5.41, 95%CI: 1.56 to 18.78) or ADL (OR 3.12, 95%CI: 1.27 to 7.67). There were wide or very wide CIs in many of these comparisons. Overall certainty of the evidence was low or very low. Further research in this field is very likely to have an important impact on our confidence in the R0 resection rates between LTX versus other neoadjuvant chemotherapy is likely to change the estimate.

Conclusions

Findings suggest that overall quality of evidence on the relative effectiveness of neoadjuvant chemotherapies was low to very low level. Therefore, we are very uncertain about the true effect of neoadjuvant therapies in the R0 resection rate in patients with gastroesophageal and gastric cancer. Future well-designed large trials are needed. To recruit large samples in this field, multicountry trials are recommended. Future trials also need to assess treatment-related adverse events, and patients-centered outcomes such as health‐related quality of life.

Incidental adenocarcinoma of the gallbladder in a patient with Y insertion gallbladder duplication in the context of recurrent biliary colic: A video case report

RATIONALE

Gallbladder cancer is the most common malignancy of the biliary tree. Despite this, the only curative therapy remains surgical resection of the lesion achieving microscopically clear margins before malignant spread has occurred. Gallbladder duplication is an uncommon anatomical variance which occurs globally. It can present in a range of ways dependent on the embryological origin of the variance.

CASE

A 52-year-old female presented for planned laparoscopic cholecystectomy in the context of cholelithiasis resulting in recurrent biliary colic. The patient had no personal history of malignancy or significant medical comorbidities.

DIAGNOSIS

Intraoperatively, the patient was found to have Y-insertion variation of gallbladder duplication. Histopathology of the resected gallbladders showed an incidental invasive gallbladder adenocarcinoma affecting one of the gallbladders.

INTERVENTION

Both gallbladders were laparoscopically resected en-bloc.

OUTCOMES

The patient underwent oncology staging, which found no evidence of metastatic spread. Regular surveillance is attended with no recurrence of disease identified.

CONCLUSION

There are few reported cases detailing the occurrence of gallbladder adenocarcinoma in the presence of duplication of the gallbladder. This case demonstrates the clinical benefit of R0 surgical resection of gallbladder cancer, whilst highlighting the difficulties of diagnosing duplication of the gallbladder or gallbladder adenocarcinoma.

Surgeon-Pathologist Team Approach Dramatically Affects Lymph Nodes Detection and Improves Patients' Short-Term Outcome

Simple Summary

Appropriate lymph node harvesting for patients with gastric cancer is fundamental for a correct staging and is strongly related to survival. In this study, we present a new protocol for on-site macroscopic evaluation and sampling of lymph nodes for gastric cancer patients. With the joint collaboration of surgeons and pathologists, our method aims to provide the largest possible number of analyzed lymph nodes per patient, allowing for a better staging. We are convinced that this approach is routinely feasible, and our preliminary results seem to confirm better patient stratification compared to other lymph node dissection methods.

Abstract

The downstaging of gastric cancer has recently gained particular attention in the field of gastric cancer surgery. The phenomenon is mainly due to an inappropriate sampling of lymph nodes during standard lymphadenectomy. Hence, collection of the maximum number of lymph nodes is a critical factor affecting the outcome of patients. None of the techniques proposed so far have demonstrated a real efficiency in increasing the number of identified lymph nodes. To harvest the maximum number of lymph nodes, we designed a protocol for on-site macroscopic evaluation and sampling of lymph nodes according to the Japanese Gastric Cancer Association protocol. The procedure was carried out by a surgeon/pathologist team in the operating room. We enrolled one hundred patients, 50 of whom belonged to the study group and 50 to a control group. The study group included patients who underwent lymph node dissection following the proposed protocol; the control group encompassed patients undergoing standard procedures for sampling. We compared the number and maximum diameter of lymph nodes collected in both groups, as well as some postoperative variables, the 30-day mortality and the overall survival. In the study group, the mean number of lymph nodes harvested was higher than the control one (p = 0.001). Moreover, by applying the proposed technique, we sampled lymph nodes with a very small diameter, some of which were metastatic. Noticeably, no difference in terms of postoperative course was identified between the two groups, again supporting the feasibility of an extended lymphadenectomy. By comparing the prognosis of patients, a better overall survival (p = 0.03) was detected in the study group; however, to date, no long-term follow-up is available. Interestingly, patients with metastasis in node stations number 8, 9, 11 or with skip metastasis, experienced a worse outcome and died. Based on our preliminary results, the pathologist/surgeon team approach seems to be a reliable option, despite of a slight increase in sfaff workload and technical cost. It allows for the harvesting of a larger number of lymph nodes and improves the outcome of the patients thanks to more precise staging and therapy. Nevertheless, since a higher number of patients are necessary to confirm our findings and assess the impact of this technique on oncological outcome, our study could serve as a proof-of-concept for a larger, multicentric collaboration.

Real-time tracking of a diffuse reflectance spectroscopy probe used to aid histological validation of margin assessment in upper gastrointestinal cancer resection surgery

SIGNIFICANCE

Diffuse reflectance spectroscopy (DRS) allows discrimination of tissue type. Its application is limited by the inability to mark the scanned tissue and the lack of real-time measurements.

AIM

This study aimed to develop a real-time tracking system to enable localization of a DRS probe to aid the classification of tumor and non-tumor tissue.

APPROACH

A green-colored marker attached to the DRS probe was detected using hue-saturation-value (HSV) segmentation. A live, augmented view of tracked optical biopsy sites was recorded in real time. Supervised classifiers were evaluated in terms of sensitivity, specificity, and overall accuracy. A developed software was used for data collection, processing, and statistical analysis.

RESULTS

The measured root mean square error (RMSE) of DRS probe tip tracking was 1.18  ±  0.58  mm and 1.05  ±  0.28  mm for the x and y dimensions, respectively. The diagnostic accuracy of the system to classify tumor and non-tumor tissue in real time was 94% for stomach and 96% for the esophagus.

CONCLUSIONS

We have successfully developed a real-time tracking and classification system for a DRS probe. When used on stomach and esophageal tissue for tumor detection, the accuracy derived demonstrates the strength and clinical value of the technique to aid margin assessment in cancer resection surgery.

Anti-Angiogenic Therapy: Current Challenges and Future Perspectives

Anti-angiogenic therapy is an old method to fight cancer that aims to abolish the nutrient and oxygen supply to the tumor cells through the decrease of the vascular network and the avoidance of new blood vessels formation. Most of the anti-angiogenic agents approved for cancer treatment rely on targeting vascular endothelial growth factor (VEGF) actions, as VEGF signaling is considered the main angiogenesis promotor. In addition to the control of angiogenesis, these drugs can potentiate immune therapy as VEGF also exhibits immunosuppressive functions. Despite the mechanistic rational that strongly supports the benefit of drugs to stop cancer progression, they revealed to be insufficient in most cases. We hypothesize that the rehabilitation of old drugs that interfere with mechanisms of angiogenesis related to tumor microenvironment might represent a promising strategy. In this review, we deepened research on the molecular mechanisms underlying anti-angiogenic strategies and their failure and went further into the alternative mechanisms that impact angiogenesis. We concluded that the combinatory targeting of alternative effectors of angiogenic pathways might be a putative solution for anti-angiogenic therapies.

Perioperative outcomes and survival in elderly patients aged ≥ 75 years undergoing gastrectomy for gastric cancer: an 18-year retrospective analysis in a single Western centre

PURPOSE

Surgical resection for elderly patients with gastric cancer is controversial. This study aims to evaluate the preoperative features and postoperative short- and long-term outcomes of elderly patients following surgical resection for gastric adenocarcinoma.

METHODS

Between January 2000 and May 2018, a total of 177 consecutive patients underwent curative gastrectomy for gastric adenocarcinoma was retrospectively reviewed. Propensity score matching (PSM) analysis was used to balance confounding covariates between the elderly and non-elderly groups. Clinicopathological characteristics, intraoperative characteristics, postoperative complications and long-term survival outcomes including overall survival (OS) and Disease Specific Survival (DSS) were compared and analysed using the Kaplan-Meier log-rank test. Multivariate cox proportional hazards regression analysis of clinicopathological factors influencing survival were evaluated.

RESULTS

There were 50 patients in the elderly group (age ≥ 75 years) and 127 patients in the non-elderly group (age < 75 years). Elderly patients had more comorbid conditions (p < 0.001), lower albumin concentration (p = 0.034), lower haemoglobin levels (p = 0.001), and poorer renal function (p = 0.043). TNM stage was similar between both groups (p = 0.174); however, lymphatic invasion (p = 0.006) and lymph node metastasis (p = 0.029) were higher in the elderly group. Elderly patients were much less likely to receive any chemo- (p < 0.001) or radiotherapy treatment (p = 0.007) with surgical treatment. After PSM, there were 50 patients in each group. Elderly patients were more likely to develop complications (Clavien Dindo ≥ 2: 50% vs. 26%, p = 0.003). The most common postoperative complications were pneumonia (12% vs. 6%, p = 0.498) and delirium (10% vs. 0%, p = 0.066). Elderly patients had a longer median length of hospital stay (median (IQR): 15.6(9.5) vs. 11.3 (9.9), p = 0.030). There were no differences in 30-day mortality (elderly vs. non-elderly: 1% vs. 1%, p = 0.988). Before and after PSM, age remains an independent predictor of postoperative complications. Before PSM, the estimated mean OS for the elderly and non-elderly patients were 108 months (95%CI, 72.5-143.5) and 143 months (95%CI, 123.0-163.8), respectively (p = 0.264). After PSM, the estimated mean OS for the elderly and non-elderly patients were 108 months (95%CI, 72.5-143.5) and 140 months (95%CI, 112.1-168.2), respectively, (p = 0.360). Before PSM, the estimated mean DSS for the elderly and non-elderly patients were 94 months (95%CI, 61.9-127.5) and 121 months (95%CI, 100.9-141.0), respectively (p = 0.405). After PSM, the estimated mean DSS for the elderly and non-elderly patients were 94 months (95%CI, 61.9-127.5) and 115 months (95%CI, 87.3-143.3), respectively (p = 0.721). Age was not an independent predictor of mortality following gastrectomy for gastric cancer in both PSM matched and unmatched cohort.

CONCLUSION

Chronological age alone is not a contraindication to curative resection of gastric adenocarcinoma in elderly patients with acceptable risk. Whilst age affects perioperative complications, the incidence of postoperative mortality and overall survival were not significantly different between elderly and non-elderly gastric cancer patients treated with curative surgery. Gastrectomy with D2 lymphadenectomy can also be performed in carefully selected elderly patients by surgeons with expertise in gastric resection along with appropriate perioperative management.

Nomogram for Predicting Survival in Advanced Gastric Cancer after Neoadjuvant Chemotherapy and Radical Surgery

BACKGROUND

Neoadjuvant chemotherapy (NAC) with subsequent radical surgery has become a popular treatment modality for advanced gastric cancer (AGC) worldwide. However, the survival benefit is still controversial, and prognostic factors remain undetermined.

AIM

To identify clinical parameters that are associated with the survival of AGC patients after NAC and radical surgery and to establish a nomogram integrating multiple factors to predict survival.

METHODS

We reviewed the medical profiles of 215 AGC patients who received NAC and radical resection, and clinical parameters concerning NAC, surgery, pathological findings, and adjuvant chemotherapy were analyzed using a Cox regression model to determine their impact on survival. Based on these factors, a nomogram was developed and validated.

RESULTS

The overall 1-year and 3-year survival rates were 85.8% and 55.6%, respectively. Younger age (<60 years old), increased examined lymph nodes (exLNs), successful R0 resection, the achievement of pathological complete response (pCR), and acceptance of adjuvant chemotherapy were positive predictors of survival. The C-index of the established nomogram was 0.785. The area under receiver operating curve (ROC) at 1/3 years of prediction was 0.694/0.736, respectively. The model showed an ideal calibration following internal bootstrap validation.

CONCLUSION

A nomogram predicting survival after NAC and surgery was established. Since this nomogram exhibited satisfactory and stable predictive power, it can be inferred that this is a practical tool for predicting AGC patient survival after NAC and radical surgery.

Characteristics of proximal early gastric cancer differentiating distal early gastric cancer

Previous studies reported substantial differences between proximal and distal gastric cancer, however, most of the cases included in these studies were advanced gastric cancers (AGCs). The aim of this study was to investigate the unique characteristics of proximal early gastric cancer (EGC) by comparing with distal EGC. From March 2007 to March 2016, proximal and distal EGC patients who underwent endoscopic or surgical resection at our institution were matched 1:3 according to age and sex. We retrospectively analyzed the clinical and histopathological information. A total of 368 patients were enrolled including 92 (25%) in the proximal and 276 (75%) in the distal group. The proportion of patients who underwent surgery (56.5 vs. 20.3%, p<0.001), undifferentiated type (38.0 vs. 19.6%, p<0.001), tumor size (29.5 ±19.4 vs. 20.3 ±16.8 mm, p<0.001) and submucosal (SM) invasion (60.9 vs. 25.7%, p<0.001) were significantly higher in the proximal group than in the distal group. In multivariate analysis, the proximal location of EGC was a significant risk factor for SM invasion in the total population (odds ratio [OR], 3.541; 95% confidence interval [CI], 2.053–6.110; p<0.001), and in subgroup with EGC < 30mm (n = 279) (OR, 5.940; 95% CI, 2.974–11.862; p<0.001). In conclusion, careful therapeutic decision of proximal EGC is essential due to the different histopathological characteristics such as large tumor size and higher potential for SM invasion.

Laparoscopic Resection for Adenocarcinoma of the Stomach or Gastroesophageal Junction Improves Postoperative Outcomes: a Propensity Score Matching Analysis

BACKGROUND

Minimally invasive resection for upper gastrointestinal tumors has been associated with favorable results. However, the role of laparoscopic surgery (LS) in the multimodal treatment of patients with advanced adenocarcinoma of the stomach or gastroesophageal junction needs further investigation.

METHODS

Clinicopathological data of patients who underwent gastrectomy between 2005 and 2017 were assessed. Outcomes of patients undergoing LS were compared with those of patients treated with a conventional open resection (OR) using a 1:1 propensity score matching analysis.

RESULTS

Curative resection for adenocarcinoma of the stomach or gastroesophageal junction was performed in 417 patients during the study period. Beginning in June 2014, the majority of patients underwent LS (n = 72) and they were matched with 72 patients who were treated with an OR. The majority of patients treated with LS (89%) had advanced cancer (UICC stages II and III) and 82% of them received neoadjuvant chemotherapy. LS was significantly associated with a higher number of harvested lymph nodes (26 (9-62) vs. 21 (4-46), P = .007), a lower 90-day major complication rate (13 vs. 26%, P = .035), and a lower length of hospital stay (14 vs. 16 days, P = .001). After a median follow-up time of 32 months, 1-year overall survival rate was higher after LS than after OR (93 vs. 74%, P = .126); however, results did not reach statistical significance.

CONCLUSION

LS for adenocarcinoma of the stomach or gastroesophageal junction is feasible and significantly reduces major postoperative morbidity resulting in a reduced length of hospital stay. Therefore, LS should be preferably considered for the curative treatment of patients with these malignancies.

A Simplified Two-Step Technique for Extended Lymphadenectomy During Resection of Gastroesophageal Malignancy: Early Results Compared to En Bloc Dissection

BACKGROUND

Extended lymph node dissection (ELND) remains an important component of curative intent resection of mid-stage gastric cancer (GC). Benefits include enhanced staging accuracy, extending regional disease control, and optimizing potential curability. ELND during gastrectomy remains underutilized in US centers due to a low prevalence of GC operations.

METHODS

The traditional en bloc ELND was modified into a two-step technique to facilitate greater ease of dissection with better exposure. After completion of the gastrectomy component, retrogastric nodes are dissected in a separate, contiguous specimen. Resulting data were compared to outcomes after en bloc resection.

RESULTS

Of 179 consecutive patients undergoing gastrectomy, 129 underwent an ELND (73%). There were 97 men and 32 women, with a median age of 64 years (range 24-98). The median total LN count was 25 (3-86). The two-step dissection yielded an average of 18.3 (± 8.5 S.D.) perigastric and 12.1 (± 5.8) retrogastric nodes. Two-step LND was associated with lower estimated blood loss (265 vs. 448 ml, p = 0.0005), lower transfusion requirements (6 vs. 28%, p = 0.007), greater mean total LN counts (30 vs. 26, p = 0.03), and a greater rate of obtaining at least 15 or 20 LNs (91 vs. 77% and 83 vs. 65%, p = 0.05). Major morbidity (overall 16%), length of stay, and survival outcomes were not different.

CONCLUSIONS

The two-step LND technique as described was found to be associated with favorable operative and postoperative outcome parameters and an excellent LN yield. It can be recommended for standard ELND indications in the absence of macroscopically abnormal LNs.

Conversion Surgery for Unresectable Advanced Gastric Cancer: A Systematic Review and Meta-Analysis

For patients with unresectable advanced gastric cancer, induction chemotherapy could down-stage primary tumors, resulting in conversion surgery becoming possible. However, the feasibility and therapeutic benefit of conversion surgery remains controversial. Therefore, this meta-analysis aimed to systematically review and investigate the efficacy of conversion surgery followed by chemotherapy for unresectable AGC.

Body mass index and mortality in patients with gastric cancer: a large cohort study

BACKGROUND

The effects of obesity on prognosis in gastric cancer are controversial.

AIMS

To evaluate the association between body mass index (BMI) and mortality in patients with gastric cancer.

METHODS

A single-institution cohort of 7765 patients with gastric cancer undergoing curative gastrectomy between October 2000 and June 2016 was categorized into six groups based on BMI: underweight (< 18.5 kg/m²), normal (18.5 to < 23 kg/m²), overweight (23 to < 25 kg/m²), mildly obese (25 to < 28 kg/m²), moderately obese (28 to < 30 kg/m²), and severely obese (≥ 30 kg/m²). Hazard ratios (HRs) for overall survival (OS) and disease-specific survival (DSS) were calculated using Cox proportional hazard models.

RESULTS

We identified 1279 (16.5%) all-cause and 763 (9.8%) disease-specific deaths among 7765 patients over 83.05 months (range 1.02-186.97) median follow-up. In multivariable analyses adjusted for statistically significant clinicopathological characteristics, preoperative BMI was associated with OS in a non-linear pattern. Compared with normal-weight patients, underweight patients had worse OS [HR 1.42; 95% confidence interval (CI) 1.15-1.77], whereas overweight (HR 0.84; 95% CI 0.73-0.97), mildly obese (HR 0.77; 95% CI 0.66-0.90), and moderately obese (HR 0.77; 95% CI 0.59-1.01) patients had better OS. DSS exhibited a similar pattern, with lowest mortality in moderately obese patients (HR 0.58; 95% CI 0.39-0.85). Spline analysis showed the lowest all-cause mortality risk at a BMI of 26.67 kg/m².

CONCLUSION

In patients undergoing curative gastric cancer surgery, those who were overweight or mildly-to-moderately obese (BMI 23 to < 30 kg/m²) preoperatively had better OS and DSS than normal-weight patients.

Cytokine-induced killer cell/dendritic cell-cytokine-induced killer cell immunotherapy for the postoperative treatment of gastric cancer: A systematic review and meta-analysis

BACKGROUND

Immunotherapy is emerging as a new treatment strategy for gastric cancer(GC). However, the efficacy and safety of this technique remain unclear. This meta-analysis aimed to assess the effect of cytokine-induced killer cell (CIK)/dendritic cell-cytokine-induced killer cell (DC-CIK) treatment for GC after surgery.

METHODS

Hazard ratio (HR), overall survival (OS) rates, and disease-free survival (DFS) rates were calculated using a Mantel-Haenszel (M-H) fixed-effects model (FEM), and results were displayed using forest plots. Publication bias was assessed by Begg test, and data were presented using funnel plots. Date robustness was assessed by the trim and fill method. Descriptive analysis was performed on T lymphocytes and adverse effects.

RESULTS

In total, 9 trials, including 1216 patients, were eligible for inclusion in this meta-analysis. Compared with the control group, the HR for OS was 0.712 (95% confidence interval [CI] 0.594-0.854) and 0.66 (95% CI 0.546-0.797) for overall (DFS). The risk ratio (RR) of the 3 and 5-year OS rate was 1.29 (95% CI 1.15-1.46) and 1.73 (95% CI 1.36-2.19), respectively. The RR for the 3 and 5-year DFS rate 1.40 (95% CI 1.19-1.65) and 2.10 (95% CI1.53-2.87), respectively. The proportion of patients who were CD3+, CD4+, and CD4+/CD8+ increased in the cellular therapy groups. No fatal adverse reactions were noted.

CONCLUSION

Chemotherapy combined with CIK/DC-CIK therapy after surgery resulted in low HR, and significantly increasing OS rates, DFS rates, and T-lymphocyte responses in patients with GC.

Extracellular Matrix Bioscaffolds for Building Gastrointestinal Tissue

Regenerative medicine is a rapidly advancing field that uses principles of tissue engineering, developmental biology, stem cell biology, immunology, and bioengineering to reconstruct diseased or damaged tissues. Biologic scaffolds composed of extracellular matrix have shown great promise as an inductive substrate to facilitate the constructive remodeling of gastrointestinal (GI) tissue damaged by neoplasia, inflammatory bowel disease, and congenital or acquired defects. The present review summarizes the preparation and use of extracellular matrix scaffolds for bioengineering of the GI tract, identifies significant advances made in regenerative medicine for the reconstruction of functional GI tissue, and describes an emerging therapeutic approach.

Decreased RNA-binding motif 5 expression is associated with tumor progression in gastric cancer

RNA-binding motif 5 is a putative tumor suppressor gene that modulates cell cycle arrest and apoptosis. We recently demonstrated that RNA-binding motif 5 inhibits cell growth through the p53 pathway. This study evaluated the clinical significance of RNA-binding motif 5 expression in gastric cancer and the effects of altered RNA-binding motif 5 expression on cancer biology in gastric cancer cells. RNA-binding motif 5 protein expression was evaluated by immunohistochemistry using the surgical specimens of 106 patients with gastric cancer. We analyzed the relationships of RNA-binding motif 5 expression with clinicopathological parameters and patient prognosis. We further explored the effects of RNA-binding motif 5 downregulation with short hairpin RNA on cell growth and p53 signaling in MKN45 gastric cancer cells. Immunohistochemistry revealed that RNA-binding motif 5 expression was decreased in 29 of 106 (27.4%) gastric cancer specimens. Decreased RNA-binding motif 5 expression was correlated with histological differentiation, depth of tumor infiltration, nodal metastasis, tumor-node-metastasis stage, and prognosis. RNA-binding motif 5 silencing enhanced gastric cancer cell proliferation and decreased p53 transcriptional activity in reporter gene assays. Conversely, restoration of RNA-binding motif 5 expression suppressed cell growth and recovered p53 transactivation in RNA-binding motif 5-silenced cells. Furthermore, RNA-binding motif 5 silencing reduced the messenger RNA and protein expression of the p53 target gene p21. Our results suggest that RNA-binding motif 5 downregulation is involved in gastric cancer progression and that RNA-binding motif 5 behaves as a tumor suppressor gene in gastric cancer.

Lymphadenectomy with Optimum of 29 Lymph Nodes Retrieved Associated with Improved Survival in Advanced Gastric Cancer: A 25,000-Patient International Database Study

BACKGROUND

Gastric adenocarcinoma is an aggressive disease with frequent lymph node (LN) metastases for which lymphadenectomy results in a survival benefit. In the US, the National Comprehensive Cancer Network guidelines recommend D2 lymphadenectomy or a minimum of 15 LNs retrieved. However, retrieval of only 15 LNs is considered by most international guidelines as inadequate. We sought to evaluate the survival benefits associated with a more complete lymphadenectomy.

STUDY DESIGN

An international database was constructed by combining gastric cancer cases from the Surveillance, Epidemiology, and End Results program database (n = 13,932) and the Yonsei University Gastric Cancer database (n = 11,358) (total n = 25,289). Kaplan-Meier survival analysis was performed along with Joinpoint analysis to obtain the optimal number of LNs to retrieve based on survival. Prognostic significance of number of nodes retrieved was then confirmed with univariate and multivariate analyses.

RESULTS

Analysis for both mean and median survival yielded 29 LNs removed as the Joinpoint. This was confirmed with multivariate analysis, where 15 retrieved LNs cutoff fell out of the model and 29 retrieved LNs remained intact, with a hazard ratio of 0.799 (95% CI 0.759 to 0.842; p < 0.001). Stage-stratified Kaplan-Meier analysis for a cutoff point of 29 LNs also demonstrated a statistically significant improvement in survival.

CONCLUSIONS

Joinpoint analysis has allowed for the creation of a model demonstrating the point at which additional dissection would not provide additional benefit. This large international dataset analysis demonstrates that the maximal survival advantage is seen by performing a lymphadenectomy with a minimum of 29 LNs retrieved.

Anastomotic leak predicts diminished long-term survival after resection for gastric and esophageal cancer

BACKGROUND

Previous studies have reported on the association between perioperative morbidity and diminished oncologic outcomes in patients undergoing resection for colorectal or pancreatic cancer. However, the effect of anastomotic leak (AL) on the survival of patients with gastric or esophageal cancer remains unclear.

METHODS

Clinicopathologic data of patients who underwent resection for gastric or esophageal cancer between 2005 and 2012 were assessed, and predictors for overall survival and disease-free survival were identified. In addition, we evaluated the impact of AL on oncologic outcomes.

RESULTS

Curative resection for gastric or esophageal cancer was performed in 471 patients. The primary tumor was located in the stomach and esophagus in 53% and 47% of the patients, respectively. Forty-one patients (8.7%) suffered an AL. The AL rate was significantly higher following resection for esophageal cancer compared with the resection for gastric cancer (12.9% vs 5.3%, P = .001). Postoperative mortality (4%) was not significantly associated with the occurrence of AL (4% without AL vs 7% with AL, P = .2). After a median follow-up time of 35 months, the median overall survival and disease-free survival were 101 and 93 months, respectively. Factors associated with worse overall survival in multivariate analysis included AL (P = .001), American Society of Anesthesiologists physical status (P < .0001), advanced Union for International Cancer Control (UICC) stage (P < .0001), and poorly differentiated carcinoma (G3; P = .04). In the multivariate analysis for predictors of disease-free survival, AL (P = .037), advanced UICC stage (P < .0001), poorly differentiated carcinoma (G3; P = .044), and lymphangiosis carcinomatosa (P = .004) were independently associated with a high risk for recurrence.

CONCLUSION

AL following resection for gastric and esophageal cancer has a negative prognostic impact on long-term survival, independent from tumor stage and biology. Further investigation of the interactions between AL and the development of tumor recurrence as well as the establishment of standardized perioperative care protocols are necessary for the improvement of outcomes after gastric and esophageal resection.

Endoscopic versus surgical resection of GI stromal tumors in the upper GI tract

BACKGROUND AND AIMS

Endoscopic resection has been performed for treatment of GI stromal tumors (GISTs) in the upper GI tract. However, the therapeutic roles of the endoscopic procedure remain debatable. We aimed in this retrospective study to evaluate the feasibility and long-term follow-up results of endoscopic resection of GISTs in the upper GI tract, compared with surgery.

METHODS

Between March 2005 and August 2014, 130 cases of GIST in the upper GI tract were resected. We compared baseline characteristics and clinical outcomes including R0 resection rate and recurrence rate between the endoscopy group (n = 90) and surgery group (n = 40).

RESULTS

The most common location of GIST was the stomach body in the endoscopy group, whereas it was the duodenum in the surgery group (P = .001). Tumor size was significantly smaller (2.3 vs 5.1 cm; P < .001), and procedure time (51.8 ± 36.2 vs 124.6 ± 74.7 minutes; P < .001) and hospital stay (3.3 ± 2.4 vs 8.3 ± 5.4 days; P < .001) were significantly shorter in the endoscopy group than in the surgery group. The R0 resection rate was 25.6% in the endoscopy group, whereas it was 85.0% in the surgery group (P = .001), and 50.0% of resected tumors belonged to a very low-risk group in the endoscopy group, whereas 35.0% and 30.0% belonged to low-risk and high-risk in the surgery group (P = .001). However, during 45.5 months of follow-up, the recurrence rate was not significantly different between the 2 groups (2.2% vs 5.0%; P = .586).

CONCLUSIONS

Endoscopic resection might be an alternative therapeutic modality for GISTs in the upper GI tract in selective cases.

Strategies and Advancements in Harnessing the Immune System for Gastric Cancer Immunotherapy

In cancer biology, cells and molecules that form the fundamental components of the tumor microenvironment play a major role in tumor initiation, and progression as well as responses to therapy. Therapeutic approaches that would enable and harness the immune system to target tumor cells mark the future of anticancer therapy as it could induce an immunological memory specific to the tumor type and further enhance tumor regression and relapse-free survival in cancer patients. Gastric cancer is one of the leading causes of cancer-related mortalities that has a modest survival benefit from existing treatment options. The advent of immunotherapy presents us with new approaches in gastric cancer treatment where adaptive cell therapies, cancer vaccines, and antibody therapies have all been used with promising outcomes. In this paper, we review the current advances and prospects in the gastric cancer immunotherapy. Special focus is laid on new strategies and clinical trials that attempt to enhance the efficacy of various immunotherapeutic modalities in gastric cancer.

Neoadjuvant chemotherapy with S-1 and cisplatin followed by D2 gastrectomy with para-aortic lymph node dissection for gastric cancer with extensive lymph node metastasis

BACKGROUND

Locally advanced gastric cancer with extensive regional and/or para-aortic lymph node (PAN) metastases is typically unresectable and associated with poor outcomes. This study investigated the safety and efficacy of S-1 plus cisplatin followed by extended surgery with PAN dissection for gastric cancer with extensive lymph node metastasis.

METHODS

Patients with gastric cancer with bulky lymph node metastasis along the coeliac artery and its branches and/or PAN metastasis received two or three 28-day cycles of S-1 plus cisplatin, followed by gastrectomy with D2 plus PAN dissection. The primary endpoint was the percentage of complete resections with clear margins in the primary tumour (R0 resection). A target sample size of 50 with one-sided α of 0.105 and β of approximately 0.2 corresponded to an expected R0 rate of 65 per cent and a threshold of 50 per cent.

RESULTS

Between February 2005 and June 2007, 53 patients were enrolled, of whom 51 were eligible. The R0 resection rate was 82 per cent. Clinical and pathological response rates were 65 and 51 per cent respectively. The 3- and 5-year overall survival rates were 59 and 53 per cent respectively. During chemotherapy, grade 3/4 neutropenia occurred in 19 per cent and grade 3/4 non-haematological adverse events in 15.4 per cent. The incidence of grade 3/4 adverse events related to surgery was 12 per cent. There were no reoperations or treatment-related deaths.

CONCLUSION

For locally advanced gastric cancer with extensive lymph node metastasis, 4-weekly S-1 plus cisplatin followed by surgery including PAN dissection was safe and effective for some patients. Further investigation of this treatment strategy is warranted.

Somatic mutations and deletions of the E-cadherin gene predict poor survival of patients with gastric cancer

PURPOSE

The prognosis of gastric cancer (GC) is poor, and the molecular pathogenesis players are vastly unknown. Surgery remains the primary option in GC treatment. The aim of this study was to investigate the impact of somatic CDH1 alterations in prognosis and survival of patients with GC.

PATIENTS AND METHODS

A series of patients with sporadic and familial GC (diffuse and intestinal; n = 246) were analyzed for somatic CDH1 mutations, promoter hypermethylation, and loss of heterozygosity (LOH) by polymerase chain reaction sequencing. E-cadherin protein expression was determined by immunohistochemistry. Associations between molecular, clinicopathologic, and survival data were analyzed.

RESULTS

CDH1 somatic alterations were found in approximately 30% of all patients with GC. Both histologic types of sporadic GC displayed LOH in 7.5%, mutations in 1.7%, and hypermethylation in 18.4% of patients. Primary tumors from hereditary diffuse GC, lacking germline CDH1 alterations, showed exclusively CDH1 promoter hypermethylation in 50% of patients. Familial intestinal GC (FIGC) tumors showed LOH in 9.4% and hypermethylation in 17.0%. CDH1 alterations did not associate with a particular pattern of E-cadherin expression. Importantly, the worst patient survival rate among all GCs analyzed was seen in patients with tumors carrying CDH1 structural alterations, preferentially those belonging to FIGC families.

CONCLUSION

CDH1 somatic alterations exist in all clinical settings and histotypes of GC and associate with different survival rates. Their screening at GC diagnosis may predict patient prognosis and is likely to improve management of patients with this disease.

A phase II trial of ixabepilone in Asian patients with advanced gastric cancer previously treated with fluoropyrimidine-based chemotherapy

PURPOSE

The highest rates of gastric cancer occur in Eastern Asia. Fluoropyrimidine-based therapy is used initially in unresectable and metastatic disease, but no single standard of care exists following disease progression. Ixabepilone, an epothilone B analog, is a non-taxane microtubule-stabilizing agent with clinical activity across multiple tumor types approved by the United States Food and Drug Administration for treatment of metastatic breast cancer.

METHODS

Asian patients with unresectable or metastatic gastric adenocarcinoma who had failed fluoropyrimidine-based chemotherapy received ixabepilone 40 mg/m(2) by 3-h intravenous infusion every 3 weeks. The primary endpoint was objective response rate (ORR).

RESULTS

Fifty-two patients were treated (65.4 % men; median age: 56.5 years). The ORR was 15.4 % (95 % confidence interval [CI] 6.9-28.1); 8 patients achieved partial responses for a median duration of 3.1 months (95 % CI 2.6-4.1 months) and 26 patients (50.0 %) had stable disease. Median progression-free survival was 2.8 months (95 % CI 2.1-3.5 months). The most common grade 3 non-hematological toxicities were fatigue (9.6 %), decreased appetite (7.7 %), sensory neuropathy (5.8 %), and diarrhea (5.8 %). Grade 3/4 neutropenia occurred in 46.2 % of patients.

CONCLUSIONS

Ixabepilone is active in Asian patients with advanced gastric cancer and shows a toxicity profile similar to those previously reported in other tumor types.

Phase II trial of combined treatment consisting of preoperative S-1 plus cisplatin followed by gastrectomy and postoperative S-1 for stage IV gastric cancer

BACKGROUND

To improve the poor prognosis in patients with stage IV (StIV) gastric cancer (GC), we conducted a multicenter phase II study of preoperative S-1 plus cisplatin followed by gastrectomy and postoperative S-1 for StIV GC (the protocol is registered at the clinical trial site of the National Cancer Institute; KYUH-UHA-GC03-01, NCT00088816).

METHODS

Eligibility criteria included histologically proven StIVGC. Patients received S-1 (80 mg/m(2)/day, days 1-21) plus cisplatin (60 mg/m(2) on day 8) for 2 courses. After preoperative chemotherapy (CTx), radical gastrectomy was performed. Postoperative S-1 (80 mg/m(2)/day, days 1-14) was administered every 3 weeks for 1 year.

RESULTS

Fifty-one patients were enrolled and all patients were followed for more than 2 years. The 2-year overall survival and progression-free survival rates were 43.1% (95% confidence interval [CI] 29.4-56.1%) and 33.3% (95% CI 20.9-46.2%), respectively. Preoperative chemotherapy was accomplished in 44 patients (86.3%). These 44 patients underwent surgery and R0 resection was achieved in 26. The rate of R0 resection for GC with a single StIV factor (n = 24) was 79.2% and that for GC with multiple StIV factors (n = 27) was 25.9%. All patients with cancer cells in peritoneal washings (cytology [Cy] 1) alone (n = 12) became Cy0 after preoperative chemotherapy. Postoperative chemotherapy was completed in 11 patients, including 8 with Cy1 alone. No treatment-related death was recorded. Recurrences were observed in 14 patients after R0 resection. The most frequent recurrence site was the peritoneum. Patients who underwent R0 resection and those with Cy1 alone had a better survival.

CONCLUSIONS

This perioperative treatment was safe and feasible for StIVGC but failed to show a survival benefit. In patients with StIVGC with Cy1 alone this treatment resulted in a better prognosis.