Nodal dissection for patients with gastric cancer: a randomised controlled trial

Positive node-ratio in curative-intent treatment for gastric cancer is a strong independent prognostic factor for 5-year overall survival

INTRODUCTION

This study addressed whether the positive node-ratio (N-ratio) for patients who underwent curative-intent treatment was an independent prognostic factor of overall survival (OS) for gastric adenocarcinoma (GA).

METHODS

Consecutive patients who underwent gastrectomy for GA with at least 15 harvested nodes were evaluated for 5-year OS. The best threshold was determined using the area under an receiver operating characteristic (ROC) curve. Univariate and multivariate models were assessed looking for independent prognostic factors for OS.

RESULTS

From 1994 to 2015, 398 consecutive patients were evaluated. The N-ratio ≥11% had an accuracy of 0.764, the sensitivity of 71.1%, the specificity of 81.7%, positive predictive value (PPV) of 91.7%, and odds ratio (OR) of 11. After multivariate analysis for OS, age ≥70 years (HR 1.44), need for total gastrectomy (HR 1.45), need for extended resection (HR 1.7), and N-ratio ≥11% (HR 3.7) were unfavorable prognostic factors. D2 lymphadenectomy (HR 0.53) was a protective factor. The median OS according to N-ratio was 14 months for N-ratio >11 vs 58 months for N-ratio <11%.

CONCLUSION

The N-ratio ≥11% was an independent negative prognostic factor for patients who underwent treatment for GA with curative intent. The N-ratio ≥11% presented high specificity, high PPV and high OR for risk of death for 5 years after surgery.

Upregulated expression of G9a is correlated with poor prognosis of gastric cancer patients

As one of the most serious cancers, gastric cancer (GC) represents the third leading cause of malignancy-related deaths. G9a is a histone lysine methyltransferase and has been reported to be involved in the progression of some human cancers. In the present study, we aimed to explore the expression patterns and clinical value of G9a in GC patients.The expression of G9a in 142 paired GC tissues and adjacent non-cancerous tissues (no less than 5 cm from tumor edge) was examined with quantitative real-time polymerase chain reaction (qRT-PCR). To estimate the association of G9a expression with clinical characteristics of GC patients, Chi-square test and t test were conducted. Kaplan-Meier survival and multivariate Cox regression analyses were performed to explore the prognostic value of G9a in GC.Upregulated expression of G9a was found in GC tissues compared with noncancerous tissues (P < .001). Elevated G9a expression was significantly correlated with patients' lymph node metastasis (P = .007) and TNM stage (P < .001). Kaplan-Meier survival curves demonstrated that patients with high G9a expression had shorter survival time than those with low expression (log-rank test, P < .05), reaching a median OS of 24 months. According to the results of Cox regression, G9a could be considered as an independent prognostic biomarker in patients with GC (HR = 3.912, 95% CI = 2.213-6.915, P < .001). Additionally, the diagnosis cut-off value of G9a in GC patients was 1.515.Taken together, G9a expression was upregulated in GC tissues and could be an effective prognostic biomarker for GC.

The Combined Use of Drainage Amylase Concentration and Serum C-reactive Protein as Predictors of Pancreas-Related Complications after Elective Gastrectomy

INTRODUCTION

Postoperative pancreas-related complications (PPRC) can cause critical conditions, including sepsis and intra-abdominal bleeding. Thus, it is important to identify patients who are at risk of clinically significant PPRC as early as possible in the postoperative period. Some authors have reported the use of amylase concentration of the drainage fluid (dAmy) to predict PPRC. However, the positive predictive value of dAmy alone is not sufficient.

OBJECTIVE

The aim of this study is to evaluate the predictive value of combined use of dAmy and serum C-reactive protein (sCRP) for PPRC.

METHODS

The clinicopathological data of 327 patients who underwent elective gastrectomy for gastric cancer were reviewed. There were 18 patients who developed PPRC. Univariate and multivariate analyses were conducted to identify the risk factors of PPRC. Receiver operating characteristic curves were used to identify the cut-off values of dAmy and sCRP on postoperative day 3 (dAmy3 and sCRP3) to predict the risk of PPRC.

RESULTS

In the multivariate analysis, splenectomy alone correlated with PPRC. The cut-off values of dAmy3 and sCRP3 were 761 IU/L and 15.15 mg/dL, respectively. Among the 17 patients with both dAmy3 and sCRP3 above the thresholds, 10 (58.8%) had PPRC with Clavien-Dindo classification (CD) ≥II and 7 (41.2%) had PPRC with CD ≥III. In contrast, among the 236 patients with both parameters below the thresholds, 233 (98.7%) did not develop PPRC, and only 1 (0.4%) had PPRC with CD ≥III.

CONCLUSIONS

Splenectomy correlates with PPRC, which is consistent with results from large clinical trials. A combined use of dAmy3 and sCRP3 can be useful in predicting the risks of PPRC.

Tumor progression-dependent angiogenesis in gastric cancer and its potential application

Despite improvements in the early diagnosis, prognosis and therapeutic strategies for gastric cancer (GC), human GC remains one of the most frequently diagnosed malignant tumors in the world, and the survival rate of GC patients remains very poor. Thus, a suitable therapeutic strategy for GC is important for prolonging survival. Both tumor cells themselves and the tumor microenvironment play an important role in tumorigenesis, including angiogenesis, inflammation, immunosuppression and metastasis. Importantly, these cells contribute to gastric carcinogenesis by altering the angiogenic phenotype switch. The development, relapse and spreading of tumors depend on new vessels that provide the nutrition, growth factors and oxygen required for continuous tumor growth. Therefore, a state of tumor dormancy could be induced by blocking tumor-associated angiogenesis. Recently, several antiangiogenic agents have been identified, and their potential for the clinical management of GC has been tested. Here, we provide an up-to-date summary of angiogenesis and the angiogenic factors associated with tumor progression in GC. We also review antiangiogenic agents with a focus on the anti-vascular endothelial growth factor receptor (VEGFR)-mediated pathway for endothelial cell growth and their angiogenesis ability in GC. However, most antiangiogenic agents have reported no benefit to overall survival (OS) compared to chemotherapy alone in local or advanced GC. In phase III clinical trials, only ramucirumab (anti-VEGFR blocker) and apatinib (VEGFR-TKI blocker) have reported an improved median overall response rate and prolonged OS and progression-free survival outcomes as a 2nd-line agent combined with chemotherapy treatment in advanced GC. By providing insights into the molecular mechanisms of angiogenesis associated with tumor progression in GC, this review will hopefully aid the optimization of antiangiogenesis strategies for GC therapy in combination with chemotherapy and adjuvant treatment.

Should All Stage N3b Patients with Advanced Gastric Cancer Be Considered Equivalent? A 30-Year Single Center Study

PURPOSE

To investigate the survival of stage N3b patients with advanced gastric cancer (AGC) after radical surgery and to evaluate the TNM staging of subgroups of stage N3b patients.

METHODS

We reviewed the data of 222 stage N3b patients with AGC who underwent D2/D3 radical surgery. Depending on the number of metastatic lymph nodes (MLNs), we divided N3b patients into several groups and compared the survival differences among them. We found that survival of patients with 16-20 MLNs was better than that of patients with ≥ 21 MLNs. Therefore, we divided the N3b patients into two subgroups and defined patients with 16-21 MLNs as N3b1 and patients with ≥ 21 MLNs as N3b2. Then, we compared survival differences between the two groups and their subgroups. Patients who underwent palliative surgery served as the reference group. In addition, we selected stage IIIB, IIIC, and IV patients from the same database to properly re-classify the N3b subgroups in the TNM staging system.

RESULTS

Survival differed significantly between the new N3b1and N3b2 groups and between the new N3b1 group and the palliative group. However, the survival of the new N3b2 group was similar to that of the palliative group. Comparisons of survival according to T staging revealed similarities between the following groups: (1) stages T2-3N3b1 and IIIB, (2) stages T4N3b1 and IIIC, and (3) stages T2-4N3b2 and IV.

CONCLUSIONS

All stage N3b patients with AGC should not be considered equivalent. A significant difference in survival was observed between stage N3b1 and N3b2 patients after radical surgery, while the survival of stage N3b2 patients was similar to that of patients who undergo palliative surgery. We recommend re-classifying stage T2-3N3b1 as TNM stage IIIB, stage T4N3b1 as stage IIIC, and T2-4N3b2 as stage IV.

Performance of a machine learning-based decision model to help clinicians decide the extent of lymphadenectomy (D1 vs. D2) in gastric cancer before surgical resection

BACKGROUND

Controversy still exists on the optimal surgical resection for potentially curable gastric cancer (GC). Use of radiologic evaluation and machine learning algorithms might predict extent of lymphadenectomy to limit unnecessary surgical treatment. We purposed to design a machine learning-based clinical decision-support model for predicting extent of lymphadenectomy (D1 vs. D2) in local advanced GC.

METHODS

Clinicoradiologic features available from routine clinical assignments in 557 patients with GCs were retrospectively interpreted by an expert panel blinded to all histopathologic information. All patients underwent surgery using standard D2 resection. Decision models were developed with a logistic regression (LR), support vector machine (SVM) and auto-encoder (AE) algorithm in 371 training and tested in 186 test data, respectively. The primary end point was to measure diagnostic performance of decision model and a Japanese gastric cancer treatment guideline version 4th (JPN 4th) criteria for discriminate D1 (pT1 + pN0) versus D2 (≥ pT1 + ≥ pN1) lymphadenectomy.

RESULTS

The decision model with AE analysis produced highest area under ROC curve (train: 0.965, 95% confidence interval (CI) 0.948-0.978; test: 0.946, 95% CI 0.925-0.978), followed by SVM (train: 0.925, 95% CI 0.902-0.944; test: 0.942, 95% CI 0.922-0.973) and LR (train: 0.886, 95% CI 0.858-0.910; test: 0.891, 95% CI 0.891-0.952). By this improvement, overtreatment was reduced from 21.7% (121/557) by treat-all pattern, to 15.1% (84/557) by JPN 4th criteria, and to 0.7-0.9% (4-5/557) by the new approach.

CONCLUSIONS

The decision model with machine learning analysis demonstrates high accuracy for identifying patients who are candidates for D1 versus D2 resection. Its approximate 14-20% improvements in overtreatment compared to treat-all pattern and JPN 4th criteria potentially increase the number of patients with local advanced GCs who can safely avoid unnecessary lymphadenectomy.

Gastric cancer surgery: historical background and perspective in Western countries versus Japan

Gastrectomy plus D2 lymphadenectomy plays a decisive role in the management of resectable gastric cancer in Japan. Before recent advances in chemotherapy, Japanese surgeons considered that extensive surgery involving extended lymphadenectomy with combined resection of neighboring organ(s) was required to eliminate any possible lymphatic cancer spread and improve patient survival. This approach differs radically from that in Western countries, which aim to improve survival outcomes by multidisciplinary approaches including perioperative chemotherapy and/or radiotherapy with limited lymph node dissection. However, a randomized controlled trial conducted in Japan found that more extensive lymphadenectomy including the para-aortic lymph nodes provided no survival benefit over D2 lymphadenectomy. Splenic hilum dissection with splenectomy also failed to show superiority over the procedure without splenectomy in patients with proximal gastric cancer, except in cases with tumor invasion of the greater curvature. Furthermore, bursectomy recently demonstrated similar outcomes to omentectomy alone. Although "D2 lymphadenectomy" as carried out in Japan contributes to low local recurrence rates and good survival outcomes, the results of randomized controlled trials have led to a decreased extent of surgical resection, with no apparent adverse effects on survival outcome. Notably, gastrectomy with D2 dissection has tended to become acceptable for advanced gastric cancer in Western countries, based on the latest results of the Dutch D1D2 trial. Differences in surgical practices between the West and Japan have thus lessened and procedures are becoming more standardized. Japanese D2 lymphadenectomy for advanced gastric cancer is evolving toward more minimally invasive approaches, while consistently striving to achieve the optimal surgical extent, thereby promoting consensus with Western counterparts.

Multimodality management of locally advanced gastric cancer-the timing and extent of surgery

The optimal treatment for patients with locally advanced gastric adenocarcinoma is multimodal. Surgery is the cornerstone of therapeutic strategies with curative intent. The addition of chemotherapy or chemoradiation decreases rate of recurrence and prolongs survival. Guidelines differ between countries and there is no universal standard of care. Modern studies of patients with locally advanced gastric cancer showed that adjuvant chemotherapy improves survival over surgery alone in Asia. These studies could not be replicated in Europe. Peri-operative chemotherapy strategies, conversely, have been effective in Europe for improving overall and disease free survival. Adjuvant chemoradiation has also demonstrated improved survival when compared to surgery alone, but studies comparing chemotherapy with chemoradiation have not shown significant difference. Trials are ongoing to examine the role of chemoradiation in a neoadjuvant fashion. A D2 extent of lymphadenectomy improves cancer related survival for those who do not undergo distal pancreatectomy/splenectomy. Survival is also associated not only with the extent but also the number of lymph nodes examined. There are ongoing trials related to immunotherapy and targeted therapies, which may also impact or change the treatment paradigm for locally advanced gastric cancer.

In Patients with Localized and Resectable Gastric Cancer, What is the Optimal Extent of Lymph Node Dissection-D1 Versus D2 Versus D3?

BACKGROUND

Despite advances in the treatment of patients with gastric cancer, the debate over the optimal extent of lymphadenectomy continues.

METHOD

A review of the classification, rationale for, and boundaries of lymphadenectomy is presented. A review of the available literature comparing D1 versus D2 versus D3 lymphadenectomy was performed and included randomized controlled trials, and prospective and retrospective comparative and non-comparative studies.

RESULTS

Earlier studies demonstrated increased morbidity with D2 compared with D1 lymphadenectomy, with no significant survival benefit. More recent studies have demonstrated survival benefit of a pancreas and spleen-sparing D2 lymphadenectomy in patients with advanced, node-positive tumors. Para-aortic/D3 dissections contribute to increased morbidity, with no survival benefit.

CONCLUSIONS

In patients with resectable gastric adenocarcinoma, a D2 lymph node dissection preserving the pancreas and spleen should be considered standard for optimal staging and treatment, provided it is performed by surgeons with sufficient expertise. Extended lymph node dissections beyond D2 should not be routinely performed as it has been shown to have increased morbidity, with no improvement in outcomes. While systemic chemotherapy should be considered standard in patients undergoing D2 lymphadenectomy, the role of adjuvant radiation continues to evolve.

Impact of perioperative treatment on survival of resectable gastric cancer patients after D2 lymphadenectomy: a single European centre propensity score matching analysis

Background To determine the effects of perioperative treatment of gastric cancer patients, we conducted an analysis with propensity score matched patient groups to determine the role of perioperative chemotherapy in patients after D2 lymphadenectomy. Patients and methods From our database of 1563 patients, 482 patients were selected with propensity score matching and divided into two balanced groups: 241 patients in the surgery only group and 241 patients in the perioperative group. The long-term results of treatment were compared between the two groups. Results Most of the included patients received radio-chemotherapy with capecitabine (n = 111; 46%) and perioperative chemotherapy with epirubicin, oxalliplatin and capecitabine (n = 91; 37.7%). 92.9% of the patients received a D2 lymph node dissection. Perioperative morbidity was similar between surgery only (18.3%) and perioperative treatment groups (20.7%) (p = 0.537). The perioperative mortality was not influenced by perioperative treatment. A pathological response was observed in 12.5% of patients. The overall 5-year and median survivals were significantly higher in the perioperative treatment group (50.5%; 51.7 moths) compared to surgery only group (41.8%; 34.9 months; p = 0.038). The subgroup analysis revealed that only patients with the TNM stages T3 (p = 0.028), N2 (p = 0.009), N3b (p = 0.043), and UICC stages IIIb (p = 0.003) and IIIc (p = 0.03) significantly benefit from perioperative treatment. Conclusions Perioperative treatment in radically resected gastric cancer patients after D2 lymphadenectomy was beneficial in stages IIIb and IIIc. The effects of perioperative treatment in lower stages could be negated by the effects of the radical surgery in lower stages and in higher stages by the biology of the disease.

Modified American Joint Committee on Cancer Tumor-Node-Metastasis Staging System Based on the Node Ratio Can Further Improve the Capacity of Prognosis Assessment for Gastric Cancer Patients

Background and Objectives: Our aim was to investigate whether the modified American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) staging system based on the node ratio can further improve the capacity of prognosis assessment for gastric cancer (GC) patients regardless of the number of lymph nodes examined (eLNs).

Methods: A total of 17,187 GC patients in the Surveillance, Epidemiology, and End Results (SEER) database were included. On the basis of a training set of 7,660 GC patients, we built the tumor-node ratio-metastasis (TNrM) staging system, which was then externally validated with a validation set of 9,527 GC patients.

Results: For the training set, the C-index value of the TNrM staging system was significantly higher than that of the AJCC 8th TNM staging system to predict survival for GC patients (C-index: 0.688 vs. 0.671, P < 0.001). Moreover, the C-index value of the TNrM staging system was significantly higher than that of the 8th TNM staging system to predict survival for GC patients with ≤15 eLNs (C-index: 0.682 vs. 0.673, P < 0.001), as well as for GC patients with >15 eLNs (C-index: 0.700 vs. 0.694, P < 0.001). Similar results were found in the validation set.

Conclusions: The TNrM staging system predicted survival more accurately and discriminatively than the AJCC 8th TNM staging system for GC patients regardless of the number of eLNs.

Factors related to patient propensity to receive adjuvant chemotherapy and outcomes in stage III gastric cancer cases after D2 surgery

BACKGROUND

Radical gastrectomy and extended lymph node (D2) dissection followed by adjuvant chemotherapy is the optimal treatment for patients with stage III gastric cancer in Asian population. The clinical factors associated with patient propensity to receive adjuvant chemotherapy and outcomes were analyzed.

METHODS

In total, 509 patients with stage III gastric cancer who had undergone D2 surgery between 2007 and 2017 at a single medical center in Taiwan were analyzed. The patients' preoperative clinical characteristics relevant to adjuvant chemotherapy adherence were analyzed using multivariate regression. Significant variables were analyzed using recursive partitioning analysis (RPA) for identifying specific patient groups with the lowest and highest probabilities of adjuvant chemotherapy adherence.

RESULTS

After surgery, 361 (70.9%) patients in the cohort had received adjuvant chemotherapy. All patients were categorized into five probability groups with adherence to adjuvant chemotherapy according to age, Eastern Cooperative Oncology Group (ECOG) performance status grade, and American Society of Anesthesiologists (ASA) class, which were discovered to be independent factors in the RPA-based probability prediction. In general, adjuvant chemotherapy improved survival across broad categories of stage III gastric cancer patients (overall survival hazard ratio: 0.53-0.75 and disease-free survival hazard ratio: 0.47-0.76).

CONCLUSIONS

Our study identified that age, ECOG grade, and ASA class were independent clinical factors associated with patient propensity to receive adjuvant chemotherapy in stage III gastric cancer. Knowledge of the clinical factors of patients may help clinicians identify and encourage specific patients to receive the adjuvant chemotherapy.

Staging of gastric cancer with the Clinical Stage Prediction score

Background

Chemotherapy with or without surgery is the first-line treatment for stage III/IV gastric cancer, while surgery is the first-line treatment for stage I/II gastric cancer. Accordingly, it is important to distinguish between stage III/IV and stage I/II gastric cancer, but clinical staging is less accurate than pathological staging. This study was performed to develop a clinical score that could distinguish stage III/IV gastric cancer from stage I/II gastric cancer.

Methods

We reviewed 2722 patients who underwent gastrectomy at our hospital from January 1996 to December 2015. As pretreatment factors potentially related to tumor stage, we assessed age, sex, tumor markers, tumor diameter, tumor location, tumor histology, and macroscopic type. Factors showing significance on multivariate analysis were used to develop the Clinical Stage Prediction score (CSP score), and a cutoff value for the score was determined by receiver operating characteristics analysis.

Results

According to multivariate analysis, clinical factors associated with stage III/IV disease were elevation of the carcinoembryonic antigen level, tumor diameter ≥ 60 mm, circumferential gastric involvement, esophageal infiltration, mucinous adenocarcinoma, and macroscopic types 2–4.

The CSP score was obtained by weighting these factors according to the non-standardized β-coefficient. Receiver operating characteristics analysis indicated that the optimum cutoff value of the CSP score was 17 points. Among 1042 patients with a CSP score ≥ 17 points, 820 patients (78.7%) had stage III/IV gastric cancer. Conversely, among 1680 patients with a CSP score < 17 points, 1547 patients (92.1%) had stage I/II gastric cancer. When discrimination of stage III/IV gastric cancer from stage I/II gastric cancer by the CSP score was assessed, the sensitivity was 78.7%, specificity was 92.1%, positive predictive value was 86.0%, and negative predictive value was 87.5%.

Conclusions

The CSP score can be helpful for differentiating stage III/IV gastric cancer from stage I/II gastric cancer based on pretreatment clinical factors.

Surgical outcomes of gastrectomy with D1 lymph node dissection performed for patients with unfavorable clinical conditions

BACKGROUND

Gastric cancer (GC) patients with advanced age and/or multiple morbidities have limited expected survival and may not benefit from extended lymph node resection. The aim of this study was to evaluate the surgical outcomes of these GC patients who underwent gastrectomy with D1 dissection.

METHODS

We retrospectively reviewed all GC patients who underwent gastrectomy with curative intent from 2009 to 2017. The decision to perform D1 was based on preoperative multidisciplinary meeting, and/or intraoperative clinical judgment.

RESULTS

Among 460 enrolled patients, 73 (15.9%) underwent D1 lymphadenectomy and 387 (84.1%) D2 lymphadenectomy. Male gender, older age, American Society of Anesthesiologists score (ASA) III/IV, higher neutrophil-to-lymphocyte ratio (NLR) and higher Charlson Comorbidity Index (CCI) were more common in the D1 group. Postoperative major complications were significantly higher in D1 group (24.7% vs 12.4%, p < 0.001) and mostly related to clinical complications. Locoregional recurrence was higher in the D1 group (53.8% vs 39.5%, p = 0.330) however, without statistical significance. No difference was found in disease-free survival (DFS) between D1 and D2 patients with positive lymph nodes (p = 0.192), whereas overall survival was longer in the D2 group (p < 0.001). Multivariate analysis showed a statistically significant impact on survival of age ≥70 years, CCI ≥5, total gastrectomy, D1 lymphadenectomy and advanced stages (III/IV).

CONCLUSIONS

Frail patients had high surgical mortality even when submitted to D1 dissection. DFS was comparable to D2. Extent of lymphadenectomy in high-risk patients should take in account the expectation of a decrease in surgical risk with the possibility of impairment of long-term survival.

Ten Thousand Consecutive Gastrectomies for Gastric Cancer: Perspectives of a Master Surgeon

As radical gastrectomy with lymph node dissection is currently the best strategy to cure gastric cancer, the role of the surgeon remains quite important in conquering it. Dr. Sung Hoon Noh, a surgeon and surgical oncologist specializing in gastric cancer, has treated gastric cancer for 30 years and has conducted over 10000 cases of gastrectomy for gastric cancer. He first adapted an electrocautery device into gastric cancer surgery and has led standardization of surgical procedures, including spleen preserving gastrectomy. His procedures based on patient-oriented insights have become the basis of the concept of enhanced recovery after surgery. He has also contributed to improving patient's survival through adoption of a multidisciplinary approach: he proved the benefit of adjuvant chemotherapy after radical D2 gastrectomy for stage II/III gastric cancer in clinical trials, updating treatment guidelines throughout the world. Dr. Noh also opened the era of precision medicine for treating gastric cancer, as he developed and validated a mRNA expression based algorithm to predict prognosis and response to chemotherapy. This article reviews his contribution and long history of service in the field of gastric cancer. The perspectives of this master surgeon, based on his profound experience and insights, will outline directions for integrative multidisciplinary health care and how can surgeons prepare for the future.

Clinicopathological differences in signet ring cell adenocarcinoma between early and advanced gastric cancer

BACKGROUND

Signet ring cell adenocarcinoma is a histological classification based on the WHO classification. The presence of this specific histological type is associated with a worse pathological appearance. The prognosis of signet ring cell adenocarcinoma in gastric cancer patients after curative surgery is still under debate.

METHODS

From January 1988 to December 2012, a total of 2971 patients, including 819 early and 2152 advanced gastric cancer patients underwent curative resection for gastric cancer. Among them, there were 185 cases of signet ring cell adenocarcinoma in early gastric cancer patients, while there were 570 cases in advanced gastric cancer patients.

RESULTS

The overall incidence of signet ring cell adenocarcinoma was 25.4%. Our results showed that the 5-year overall survival rates of early gastric cancer patients with signet ring cell adenocarcinoma and non-signet ring cell adenocarcinoma were 90.7 and 83.2%, respectively (P = 0.001). The 5-year disease-free survival rates of early gastric cancer patients with signet ring cell adenocarcinoma and non-signet ring cell adenocarcinoma were 87.4 and 81.6%, respectively (P = 0.003). The 5-year overall survival rates of advanced gastric cancer patients with signet ring cell adenocarcinoma and non-signet ring cell adenocarcinoma were 32.1 and 37.9%, respectively (P = 0.041). The 5-year disease-free survival rates of advanced gastric cancer patients with signet ring cell adenocarcinoma and non-signet ring cell adenocarcinoma were 28.6 and 35.2%, respectively (P = 0.037). Signet ring cell adenocarcinoma was an independent predictor for overall survival in advanced gastric cancer (P = 0.017).

CONCLUSION

The clinical features and prognosis of signet ring cell adenocarcinoma are different between early and advanced gastric cancer. Signet ring cell adenocarcinoma is a poor prognostic factor in advanced gastric cancer after curative resection.

Gastric cancer: factors affecting survival

BACKGROUND AND AIM

The present multicenter, retrospective study aimed at determining the factors affecting survival in patients who were operated on due to gastric cancer (GC).

PATIENTS AND METHODS

The data of 234 patients, who underwent elective surgery due to GC were retrospectively analyzed. The demographic characteristics, tumor localization and diameter, type of resection and lymph node dissection, experience of the operating surgeon (senior or junior), tumor grade, pT stage, number of lymph nodes harvested, number of lymph nodes with and without metastasis, tumor stage and survival data were recorded.

RESULTS

Survival was better a tumor diameter <4 cm, lower localization, experience of the operating surgeon (senior), without metastatic lymph nodes, tumor grade and decreased invasion depth (p < .05). There was no statistically significant difference between D1 LND and D2 LND with respect to survival (p = .793). Mortality was higher and survival was lower in patients with metastatic lymph nodes (p = .001). A number of harvested lymph nodes of 16 or more increased mortality (p = .003). Also, as disease stage increased, there was a decrease in survival and increase in mortality rates (p = .001).

CONCLUSIONS

Survival outcomes in resectable GCs are affected by the experience of the surgeon and patient-related factors at the time of surgery, including tumor size, T stage, and presence of metastatic lymph nodes.

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.

A prognostic model based on lymph node metastatic ratio for predicting survival outcome in gastric cancer patients with N3b subclassification

BACKGROUND

Determining the survival outcome for gastric cancer patients with metastases to more than 15 regional lymph nodes is difficult. This study aims to develop a lymph node metastatic ratio (LNR)-based prognostic model to predict the survival outcome after D2 surgery in such patient groups.

METHODS

Our study retrospectively enrolled 139 gastric cancer patients with metastases to more than 15 regional lymph nodes who underwent D2 surgery between 2007 and 2014. Clinicopathologic variables to predict overall survival (OS) using multivariate Cox regression were selected to create a prognostic model.

RESULTS

The prognostic model for predicting OS was developed based on five independent factors, namely, T-classification (T2 or T3 vs. T4), LNR (<0.80 vs. ≥0.80), carcinoembryonic antigen level (<5 vs. ≥5 ng/ml), Eastern Cooperative Oncology Group performance scale (scale 0-1 vs. ≥2), and adjuvant chemotherapy (yes vs. no). Using the prognostic score, patients were stratified into good, intermediate, and poor prognostic groups. The median OS in the good, intermediate, and poor prognostic risk groups was 32.0 months (95% confidence interval [CI]: 22.3-41.7), 12.4 months (95% CI: 8.5-16.3), and 5.4 months (95% CI: 2.1-8.7), respectively. The c-index of the prognostic model was 0.79 (95% CI: 0.71-0.87).

CONCLUSION

This study developed an accurate LNR-based prognostic model for predicting the survival outcome after D2 surgery in gastric cancer patients with metastasis to more than 15 regional lymph nodes. This model might assist clinicians in prognostic stratification of such patients and convince eligible patients to receive adjuvant chemotherapy.

Advanced gastric cancer: the value of surgery

Gastric cancer is a common disease with high mortality. The definition of advanced gastric cancer is still debated. Radical surgery associated to appropriate systemic and intra-abdominal chemotherapy is the gold standard treatment. In presence of peritoneal carcinosis, reaching a complete cytoreduction is the key to achieve long-term survival. Adequate lymphadenectomy is also fundamental. Conversion therapy could be applied to selected IV stage patients. No definitive evidences exist regarding the oncological and surgical superiority of mini-invasive approaches over the classical open techniques.

D2 lymphadenectomy for gastric cancer as an independent prognostic factor of 10-year overall survival

BACKGROUND

The extension of lymphadenectomy for GA remains on debate even after Eastern and Western clinical trials. The main concern is if morbidity of extended lymphadenectomy could be justified based on benefits in oncologic outcomes. This study addressed the extension of lymphadenectomy as a prognostic factor of overall survival (OS) for gastric adenocarcinoma (GA).

METHODS

Consecutive patients who underwent gastrectomy for GA were retrospectively evaluated. Univariate and multivariate models assessed determinants of OS.

RESULTS

From 1994 to 2015, 656 consecutive patients who underwent gastrectomy were evaluated. Briefly, 455 (69.4%) were male, 397 (60.5%) underwent total gastrectomy, Roux-en-Y reconstruction was done in 483 (73.6%), and R0 resection was achieved in 632 patients (96.3%). According to multivariate analysis, the risk of death was increased with older age (≥70-y), high-grade tumors, lesions ≥ 5 cm, positive nodes ≥ 3, and extra-gastric resections. Otherwise, D2 lymphadenectomy improved median OS (37 versus 16 months), 3-y (51.1 versus 32.2%), 5-y (43.2 versus 26), and 10-y OS (30.6 versus 9.4%), with HR of 0.48 (95% CI 0.34-0.67, p < 0.001). The general median OS was 31 months and 3-, 5-, and 10-y were 47.6, 40, and 27%, respectively. The median follow-up for all patients was 26 months, and for survivors was 65 months.

CONCLUSION

This study showed D2 lymphadenectomy for GA as an independent prognostic factor for OS, even after 5-y and until 10-y. Our study suggests that D2 should be offered as the curative-intent treatment for all patients with GA that fit to undergo surgery.

Gastric Cancer Etiology and Management in Asia and the West

Regional variation in treatment paradigms for gastric adenocarcinoma has attracted a great deal of interest. Between Asia and the West, major differences have been identified in tumor biology, implementation of screening programs, extent of surgical lymphadenectomy, and routine use of neoadjuvant versus adjuvant treatment strategies. Minimally invasive techniques, including both laparoscopic and robotic platforms, have been studied in both regions, with attention to safety, feasibility, and long-term oncologic outcomes. The purpose of this review is to discuss advances in the understanding of the etiology and underlying biology of gastric cancer, as well as the current state of management, focusing on the differences between Asia and the West.

Reporting of outcomes in gastric cancer surgery trials: a systematic review

BACKGROUND

The development of clinical guidelines for the surgical management of gastric cancer should be based on robust evidence from well-designed trials. Being able to reliably compare and combine the outcomes of these trials is a key factor in this process.

OBJECTIVES

To examine variation in outcome reporting by surgical trials for gastric cancer and to identify outcomes for prioritisation in an international consensus study to develop a core outcome set in this field.

DATA SOURCES

Systematic literature searches (Evidence Based Medicine, MEDLINE, EMBASE, CINAHL, ClinicalTrials.gov and WHO ICTRP) and a review of study protocols of randomised controlled trials, published between 1996 and 2016.

INTERVENTION

Therapeutic surgical interventions for gastric cancer. Outcomes were listed verbatim, categorised into groups (outcome themes) and examined for definitions and measurement instruments.

RESULTS

Of 1919 abstracts screened, 32 trials (9073 participants) were identified. A total of 749 outcomes were reported of which 96 (13%) were accompanied by an attempted definition. No single outcome was reported by all trials. 'Adverse events' was the most frequently reported 'outcome theme' in which 240 unique terms were described. 12 trials (38%) classified complications according to severity, with 5 (16%) using a formal classification system (Clavien-Dindo or Accordion scale). Of 27 trials which described 'short-term' mortality, 15 (47%) used one of five different definitions. 6 out of the 32 trials (19%) described 'patient-reported outcomes'.

CONCLUSION

Reporting of outcomes in gastric cancer surgery trials is inconsistent. A consensus approach to develop a minimum set of well-defined, standardised outcomes to be used by all future trials examining therapeutic surgical interventions for gastric cancer is needed. This should consider the views of all key stakeholders, including patients.

Therapeutic Value of Lymph Node Dissection Along the Superior Mesenteric Vein and the Posterior Surface of the Pancreatic Head in Gastric Cancer Located in the Lower Third of the Stomach

Background

Therapeutic value of lymph node dissection along the superior mesenteric vein (14v) and the posterior surface of the pancreatic head (13) remains unclear in gastric cancer patients.

Methods

We reviewed 355 patients with advanced gastric cancer in the lower third of the stomach who had undergone gastrectomy at our hospital.

Results

The frequency of lymph node (LN) metastasis was 10.2% and 7.4% in stations 13 and 14v, respectively. The frequency of station 13 metastasis was 26.8% for T3/T4 tumors with group 2 LNs metastasis and 1.4% for all other tumors. The frequency of station 14v metastasis was 22.2% for T3/T4 tumors with group 2 LNs metastasis and 1.8% for all other tumors. The therapeutic values for dissecting LN stations 13 and 14v were 1.9 and 0.9, respectively, similar to the therapeutic value for group 2 LN dissection.

Conclusion

Because metastasis to stations 13 and 14v occurs frequently in patients with T3/T4 gastric cancer located in the lower third of the stomach who also have metastasis to group 2 LNs, stations 13 and 14v should be dissected in these patients.

MicroRNA-96 expression induced by low-dose cisplatin or doxorubicin regulates chemosensitivity, cell death and proliferation in gastric cancer SGC7901 cells by targeting FOXO1

MicroRNA-96 (miR-96) is transcriptionally associated with the induction of chemoresistance following chemotherapy by targeting to FOXO1 mRNA at one of two predicted binding sites in its 3'-untranslated region sequence. The upregulation of miR-96 is associated with a high risk of chemoresistance. Nevertheless, the mechanism by which miR-96 is upregulated remains largely undefined. In the present study, the gastric cancer SGC7901 cell line was treated with different doses of the chemotherapeutic agents cisplatin and doxorubicin. miR-96 expression was analyzed by reverse transcription-quantitative polymerase chain reaction at different time points. Western blot and chromatin immunoprecipitation were performed to analyze the expression levels of the target gene. The effects of miR-96 on chemosensitivity were assessed by a carboxyfluorescein succinimidyl ester/propidium iodide labeling assay, and its effects on proliferation were assessed by Cell Counting Kit-8 or EdU staining assays. The results demonstrated that treatment with a low dose of either chemotherapeutic agent induced miR-96 expression. Upregulation of miR-96 caused the post-transcriptional repression of FOXO1 expression. Decreases in FOXO1 protein levels led to a decrease in the transcriptional activity of the cyclin-dependent kinase inhibitor 1A (CDKN1A, also known as p21) promoter region, and thus the expression of p21 was downregulated in a tumor protein p53-independent manner. As a result, induction of miR-96 expression caused chemoresistance and promoted proliferation in SGC7901 cells. Taken together, the results of the present study revealed that treatment with cisplatin or doxorubicin could induce expression of miR-96 at certain doses. Upregulation of miR-96 is partially associated with chemoresistance and miR-96 can also promote cell proliferation by repressing p21.

Compliance to D2 lymphadenectomy in laparoscopic gastrectomy

The objective of this study is to describe the compliance to D2 lymphadenectomy in laparoscopic gastrectomy. Radical partial or total gastrectomy with modified D2 lymphadenectomy is the standard of care for locally advanced gastric cancer. It is unclear whether compliance to D2 lymphadenectomy in laparoscopy is comparable to that in open surgery. A review of the literature was performed and results are described in a descriptive review. Available randomized trials are mostly performed for early gastric cancer, for which formal D2 lymphadenectomy is usually not required. Most trials report no differences in number of retrieved lymph nodes between open and laparoscopic gastrectomy. Only one trial used adherence to D2 lymphadenectomy as primary outcome parameter, and found no difference between laparoscopic and open gastrectomy. Results from randomized trials in advanced gastric cancer are awaited. In the meantime, the laparoscopic approach can be used in experienced centers.

Favoring D2-Lymphadenectomy in Gastric Cancer

The role of extended lymphadenectomy in the surgical treatment of gastric cancer has been debated for many years. So far six prospective randomized trials and a number of meta-analyses comparing D₁- to D₂-lymphadenectomy in open surgery have been published with contradicting results. The possible oncologic benefit of radical lymphadenectomy has been blurred by a number of reasons. In most of the trials the strategies under comparison were made similar after protocol violations. Imperfect design of the trials could not exclude the influence of cofounding factors. Inappropriate endpoints could not detect evidently the difference between the two surgical strategies. On the other hand radical lymphadenectomy was characterized by increased morbidity and mortality. This was mostly caused by the addition of pancreatico-splenectomy in all D₂-dissections, even when not indicated. A careful analysis of the available evidence indicates that D₂-lymphadenectomy performed by adequately trained surgeons without resection of the pancreas and/or spleen, unless otherwise indicated, decreases Gastric Cancer Related Deaths and increases Disease Specific Survival. This evidence is not compelling but cannot be ignored. D₂-lymphadendctomy is nowadays considered to be the standard of care for resectable gastric cancer.

Prognostic significance of suprapancreatic lymph nodes and its implication on D2 dissection

There have been few studies on the prognostic significance of suprapancreatic lymph nodes (SPLNs), which are targeted in D2 dissections in patients with gastric cancer. The aim of this study was to investigate the prognostic significance of SPLNs by determining whether treatment outcomes of SPLN-positive gastric cancer are comparable to that of SPLN-negative cancer.This study enrolled patients with node-positive gastric cancer, who underwent curative surgery with D2 dissection, at the Samsung Medical Centre from 2007 to 2009. The survival outcomes of patients with and without metastatic SPLNs were analyzed.The total number of patients was 1086, with 377 patients (34.7%) having metastatic SPLNs. SPLN positivity was associated with a more advanced tumor status and the 5-year survival rate of the SPLN-positive group was significantly lower than that of the SPLN-negative group (59.5% vs 81.2%, P < .001). However, the survival was not significantly different between the 2 groups when comparing SPLN status within a given disease stage. Cox multivariate analysis revealed that SPLN metastasis was not an independent prognostic factor.SPLNs were not different from perigastric lymph nodes in terms of prognostic significance and SPLN metastasis should be regarded as a locoregional disease. Complete removal of SPLNs by D2 dissection is recommended for the locoregional control of gastric cancer.

Is There Any Role for D3 Lymphadenectomy in Gastric Cancer?

Although D2 constitutes the level of lymph node dissection which most surgical associations endorse in their treatment guidelines for gastric cancer more extended D3 dissection has also been attempted to improve oncologic outcomes. Existing literature pertinent with the provisional therapeutic impact of D3 lymphadenectomy in advanced gastric cancer is studied in this mini review. Seven non-randomized comparisons, three randomized trials and five meta-analyses, almost exclusively of Asian origin, were identified and examined. D3 compared to D2 lymphadenectomy consistently and significantly proved to be associated with a “heavier” iatrogenic surgical trauma translated to more blood loss, prolonged operative time, higher relaparotomy rates and post-procedural surgical and non-surgical morbidity. Oddly mortality in most of these series did not reach statistical significance a fact probably attributed to Asian surgical expertise and/or methodologic drawbacks. All existing evidence and their meta-analyses, including a well-designed RCT from Japan (JCOG), failed to support a clear overall survival benefit linked to D3 dissection thus excluding the procedure from current treatment algorithms. The Italian GC research group, analyzing their database, proposed tumor histology, macroscopic type, size and location as selection criteria for D3 dissection provided surgical expertise is available. Recently, a phase II clinical trial from Japan reported a 3 -year survival rate of 59% in patients with clinically involved para-aortic nodes treated with neoadjuvant chemotherapy followed by D3 lymphadenectomy, rekindled the issue. Future multicenter randomized trials should test the extend and after effect of lymphadenectomy in gastric cancer combined with modern chemotherapeutic agents in multimodal treatments.

Simultaneous sentinel lymph node computed tomography and locoregional chemotherapy for lymph node metastasis in rabbit using an iodine-docetaxel emulsion

Purpose

A sentinel lymph node (SLN) tracer can gain multi-functionality by combining it with additional components. We developed a SLN tracer consisting of iodine and docetaxel and applied it as a theragnostic nanoparticle to simultaneously perform SLN computed tomography (CT) lymphography and locoregional chemotherapy of the draining lymphatic system.

Results

Docetaxel could be loaded in iodine emulsions at a drug-to-surfactant weight ratio as high as that in the drug formulation Taxotere^®. The particle size and drug concentration were stable during storage for up to 3 months in optimized nanoemulsions. Popliteal LN enhancement on CT was observed in all healthy rabbits (n=3) and VX2 tumor-implanted rabbits (n=6) 12 hours after injection. The rate of SLN metastasis was significantly lower in the treatment group (29.4%, 5/17) than in the non-treatment group (70.6%, 12/17) (P=0.038).

Material and Methods

We prepared a nanoemulsion carrying both iodine and docetaxel in a single structure by optimizing the composition of surfactants surrounding the inner iodized oil core. CT was performed 12 hours after subcutaneous injection of the emulsion in healthy rabbits (n=3) and VX2 tumor-implanted rabbits (n=6) for SLN imaging. Next, we tested the effect of treatment by histopathologically assessing the popliteal LN metastasis rate in VX2 tumor-implanted rabbits 7 days after subcutaneous injection of the emulsion (treatment group, n=17) and comparing it with that of non-treatment group rabbits (n=17).

Conclusions

We developed an iodine-docetaxel emulsion and demonstrated that it can be applied to simultaneously achieve CT SLN imaging and local chemotherapy against nodal metastasis.

Gastrectomy with Extended Lymphadenectomy: a North American Perspective

PURPOSE

Despite evidence of oncologic benefits from extended (D2) lymphadenectomy in gastric cancer from many East Asian studies, there is persistent debate over its use in the West, mainly due to perceived high rates of morbidity and mortality. This study evaluates the safety and efficacy of D2 dissection in a high-volume North American center.

METHODS

A prospectively entered database of all patients undergoing gastrectomy for cancer at a North American referral center from 2005 to 2016 was reviewed. Wedge resections, thoracoabdominal approach, emergency surgery, palliative operations, and non-adenocarcinoma cases were excluded.

RESULTS

Of 366 non-bariatric gastrectomies over this period, 175 met the inclusion criteria. Median age was 73 years and 69% were male. One hundred forty-one patients (80%) underwent D2 dissection, the rest having D1. There was no difference in postoperative complications (D1 = 44%: D2 = 42%), anastomotic leaks (D1 = 6%: D2 = 5%), and same-admission or 30-day mortality (D1 = 6%: D2 = 2%). D2 dissection was associated with higher pathological stage (72% > stage 1 vs 38% > stage 1; p < 0.05) and median lymph node yield (30 vs 14; p < 0.05), with no difference in complete resection (R0) rate (D1 = 98% vs D2 = 92%). Laparoscopic approach was employed in 34% (45/141) of D2 cases, resulting in shorter median length of stay (6 days vs 9; p < 0.05) and equivalent oncologic outcomes compared to open D2.

CONCLUSION

This study supports the use of D2 lymphadenectomy, by either open or laparoscopic approach, in high-volume North American centers as a safe and effective oncologic procedure for gastric cancer, with equivalent complication rates and superior lymph node yield to traditional D1 dissection.

Survival benefit of "D2-plus" gastrectomy in gastric cancer patients with duodenal invasion

BACKGROUND

The optimal extent of lymph node (LN) dissection for gastric cancer with duodenal invasion is yet to be clarified. This study sought to evaluate the significance of gastrectomy with D2-plus lymphadenectomy including posterior LNs along the common hepatic artery (no. 8p), hepatoduodenal ligament LNs along the bile duct (no. 12b) and those behind the portal vein (no. 12p), LNs on the posterior surface of the pancreatic head (no. 13), LNs along the superior mesenteric vein (no. 14v) and para-aortic LNs around the left renal vein (nos. 16a2 and 16b1) dissection.

METHODS

Patients with gastric cancer with duodenal invasion undergoing R0 gastrectomy from January 2000 to December 2015 were enrolled. The therapeutic value index (TVI) of each LN dissection was calculated by multiplying the incidence of metastasis to each LN station by the 5-year overall survival (OS) rate of the patients with metastasis to the station.

RESULTS

In total, 117 patients were eligible. The 5-year OS rates (and TVI) of the patients with metastasis to LNs were 40.4% (7.4) in no. 12b, 25.4% (6.8) in no. 13, 32.0% (6.1) in no. 14v, 50.0% (13.0) in no. 16a2 and 40.0% (10.0) in no. 16b1. None of the patients with metastasis in no. 8p or no. 12p survived 5 years or longer.

CONCLUSION

In a potentially curative gastrectomy for gastric cancer with duodenal invasion, there may be some survival benefit in dissection of nos. 12b, 13, 14v, 16a2 and 16b1 LNs, while no benefit was seen in dissection of nos. 8p or 12p LNs.

Caspase-3, a key apoptotic protein, as a prognostic marker in gastric cancer after curative surgery

BACKGROUND

Caspase-3 acts as a major executioner protein in proteolytic degradation during apoptosis. The role of Caspase-3 in gastric cancer remains controversial.

METHODS

A total of 366 gastric cancer patients who received curative surgery were enrolled. Caspase-3 expression in gastric tumors was examined by immunohistochemical staining. Correlations between Caspase-3 expression and the survival rates and between Caspase-3 expression and the clinicopathological parameters of the gastric cancer patients were analyzed.

RESULTS

The 5-year overall survival rates of gastric cancer patients with and without Caspase-3 expression were 51.2% and 37.3%, respectively (P = 0.030). The 5-year disease-free survival rates of gastric cancer patients with and without Caspase-3 expression were 49.2% and 34.6%, respectively (P = 0.029). Analyses of the clinicopathological features showed that larger tumor size (P = 0.030), more advanced Borrmann type (P = 0.012), more aggressive stromal reaction (P = 0.001), higher classification using Ming's infiltrating histology type (P = 0.018), more lymph node involvement (P = 0.019), and more lymphovascular involvement (P = 0.045) were significantly correlated with a lack of Caspase-3 expression. The multivariate analysis showed that age (P = 0.001), Borrmann classification (P = 0.032), stromal reaction type (P = 0.018), TNM pathological T category (P = 0.002), TNM pathological N category (P < 0.001), and Caspase-3 expression (P = 0.041) were significantly correlated with the overall survival of gastric cancer patients.

CONCLUSION

Caspase-3 expression in gastric cancer patients is related to favorable clinicopathological features and a positive prognosis after curative surgery. Caspase-3 may act as a tumor suppressor in human gastric cancer.

Diagnostic evaluation of sentinel lymph node biopsy using indocyanine green and infrared or fluorescent imaging in gastric cancer: a systematic review and meta-analysis

BACKGROUND

Sentinel node navigation surgery (SNNS) for gastric cancer using infrared visualization of indocyanine green (ICG) is intriguing because it may limit operative morbidity. We are the first to systematically review and perform meta-analysis on the diagnostic utility of ICG and infrared electronic endoscopy (IREE) or near infrared fluorescent imaging (NIFI) for SNNS exclusively in gastric cancer.

METHODS

A search of electronic databases MEDLINE, EMBASE, SCOPUS, Web of Science, and the Cochrane Library using search terms "gastric/stomach" AND "tumor/carcinoma/cancer/neoplasm/adenocarcinoma/malignancy" AND "indocyanine green" was completed in May 2017. Articles were selected by two independent reviewers based on the following major inclusion criteria: (1) diagnostic accuracy study design; (2) indocyanine green was injected at tumor site; (3) IREE or NIFI was used for intraoperative visualization. 327 titles or abstracts were screened. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2.

RESULTS

Ten full text studies were selected. 643 patients were identified with the majority of patients possessing T1 tumors (79.8%). Pooled identification rate, diagnostic odds ratio, sensitivity, and specificity were 0.99 (0.97-1.0), 380.0 (68.71-2101), 0.87 (0.80-0.93), and 1.00 (0.99-1.00), respectively. The summary receiver operator characteristic for ICG + IREE/NIFI demonstrated a test accuracy of 98.3%. Subgroup analysis found improved test performance for studies with low-risk QUADAS-2 scores, studies published after 2010 and submucosal ICG injection. IREE had improved diagnostic odds ratio, sensitivity, and identification rate compared to NIFI. Heterogeneity among studies ranged from low (I² < 25%) to high (I² > 75%).

CONCLUSIONS

We found encouraging results regarding the accuracy, diagnostic odds ratio, and specificity of the test. The sensitivity was not optimal but may be improved by a strict protocol to augment the technique. Given the number and heterogeneity of studies, our results must be viewed with caution.

Laparoscopic-assisted total gastrectomy for adenocarcinoma in a western country: Safety and oncological issues

Background

Laparoscopic total gastrectomy for adenocarcinoma is a widely diffused operation in eastern countries, but there are only a few reports from western centers. We assessed a single surgeon's experience at a single, nonacademic, community hospital.

Methods

Short-term outcome of patients undergoing laparoscopic total gastrectomy for adenocarcinoma (June 2005-March 2010) was assessed.

Results

Fourteen patients (5 males, 9 females; median age, 66.8 years [interquartile range, 59.7–71.8]) underwent laparoscopic total gastrectomy. The median operative time was 240 min. There were five stage 1 patients, five stage 2, and four stage 3; R0 resection was obtained in all 14 patients, and the median number of lymph nodes retrieved was 38. Mortality and overall morbidity rates were 0% and 35.7%, respectively.

Conclusions

The outcomes of laparoscopic total gastrectomy for adenocarcinoma performed by a well-trained laparoscopic surgeon working in a community hospital are good in terms of safety for the patients and response to the oncological criteria used in open surgery.

Usefulness of Combined PET/CT to Assess Regional Lymph Node Involvement in Gastric Cancer

Aims and Background

The aim of this study was to evaluate the value of positron emission tomography/computed tomography (PET/CT) for preoperative staging of gastric cancer and to compare the diagnostic performance of PET/CT with that of contrast-enhanced computed tomography (CECT).

Methods

We retrospectively reviewed 74 gastric cancer patients who underwent preoperative PET/CT and CECT, and subsequent curative surgical resection between April 2007 and July 2011. Preoperative PET/CT and CECT images for primary tumors of the stomach and lymph node metastases were reviewed retrospectively. The final diagnoses of primary tumors and LN metastases were based on histopathological specimens in all patients.

Results

Advanced gastric cancer was present in 65% of patients (n = 48), and the remaining patients had early gastric cancer (n = 26). Sixteen patients (22%) showed signet-ring-cell histology. For the detection of the primary tumor, the sensitivity of PET/CT was significantly higher than that of CECT (67% vs 55%, respectively; P = 0.049). For the evaluation of regional lymph node metastasis, the sensitivity, specificity, and accuracy of PET/CT and CECT were 34% and 51% (P = 0.065), 88% and 79% (P = 0.687), and 58% and 64% (P = 0.332), respectively. Neither PET/CT nor CECT detected regional lymph node metastases in early gastric cancer patients. Signet-ringcell histology showed trends of non-FDG-avid lymph node metastases (odds ratio = 0.15, 95% confidence interval 0.17–1.37, P = 0.093)

Conclusions

The accuracy of PET/CT is low and it is not a useful tool in the staging of gastric cancer overall in early gastric cancer and in signet-ring-cell carcinoma. Furthermore, the sensitivity of PET/CT could be inferior to that of CECT in the diagnosis of regional lymph node metastasis.

Neoadjuvant chemotherapy for gastric cancer. Is it a must or a fake?

AIM

To investigate the neoadjuvant chemotherapy (NAC) effect on the survival of patients with proper stomach cancer submitted to D2 gastrectomy.

METHODS

We proceeded to a review of the literature with PubMed, Embase, ASCO and ESMO meeting abstracts as well as computerized use of the Cochrane Library for randomized controlled trials (RCTs) comparing NAC followed by surgery (NAC + S) with surgery alone (SA) for gastric cancer (GC). The primary outcome was the overall survival rate. Secondary outcomes were the site of the primary tumor, extension of node dissection according to Japanese Gastric Cancer Association (JGCA) performed in both arms, disease-specific (DSS) and disease-free survival (DFS) rates, clinical and pathological response rates and resectability rates after perioperative treatment.

RESULTS

We identified a total of 16 randomized controlled trials comparing NAC + S (n = 1089) with SA (n = 973) published in the period from January 1993 - March 2017. Only 6 of these studies were well-designed, structured trials in which the type of lymph node (LN) dissection performed or at least suggested in the trial protocol was reported. Two out of three of the RCTs with D2 lymphadenectomy performed in almost all cases failed to show survival benefit in the NAC arm. In the third RCT, the survival rate was not even reported, and the primary end points were the clinical outcomes of surgery with and without NAC. In the remaining three RCTs, D2 lymph node dissection was performed in less than 50% of cases or only recommended in the “Study Treatment” protocol without any description in the results of the procedure really perfomed. In one of the two studies, the benefit of NAC was evident only for esophagogastric junction (EGJ) cancers. In the second study, there was no overall survival benefit of NAC. In the last trial, which documented a survival benefit for the NAC arm, the chemotherapy effect was mostly evident for EGJ cancer, and more than one-fourth of patients did not have a proper stomach cancer. Additionally, several patients did not receive resectional surgery. Furthermore, the survival rates of international reference centers that provide adequate surgery for homogeneous stomach cancer patients’ populations are even higher than the survival rates reported after NAC followed by incomplete surgery.

CONCLUSION

NAC for GC has been rapidly introduced in international western guidelines without an evidence-based medicine-related demonstration of its efficacy for a homogeneous population of patients with only stomach tumors submitted to adequate surgery following JGCA guidelines with extended (D2) LN dissection. Additional larger sample-size multicentre RCTs comparing the newer NAC regimens including molecular therapies followed by adequate extended surgery with surgery alone are needed.

Effect of total number of harvested lymph nodes on survival outcomes after curative resection for gastric adenocarcinoma: findings from an eastern high-volume gastric cancer center

BACKGROUND

Greater lymph node retrieval in gastric cancer improves staging accuracy and may improve survival from increased clearance of nodal micrometastasis. This retrospective cohort study investigated if more lymph nodes removed in gastric cancer increases survival and if such effect is stage-specific due to differential risks of nodal micrometastasis and systemic disease.

METHODS

The prospectively collected database of curatively resected gastric cancer patients in National Cancer Center, South Korea between 2000 and 2009 was reviewed. Disease-free survival (DFS) and overall survival (OS) for all patients and for each stage according to number of lymph nodes examined (1-30, 31-45, > 45) were analyzed.

RESULTS

Of 4049 patients, 96.6% and 98.4% underwent D2 (perigastric and extragastric) lymphadenectomy and had ≥ 15 lymph nodes examined. Mean number of nodes examined was 43. Five-year OS & DFS rates were 83.3% and 80.7%. Patients with > 45 nodes examined had significantly lower DFS (p = 0.002) and OS (p = 0.007) compared to those with 1-30 and 31-45 nodes. However, proportion of patients with > 45 nodes examined increased with stage (p = 0.0005). Per stage, there was no significant difference in DFS and OS according to number of nodes examined except for stage IIIA favoring more nodes (p = 0.018 and p = 0.044, respectively). Similar trend was seen in stage IIB. Number of examined nodes positively correlated with number of pathologic nodes for all patients (r = 0.144, p < .001) but not for stage IIB and IIIA. Number of nodes examined was a significant survival predictor in stage IIIA.

CONCLUSION

Greater lymph node harvest showed improved survival in intermediate-stage gastric cancer.

Adjuvant Chemotherapy Improves Survival in Stage III Gastric Cancer after D2 Surgery

Background: Stage III gastric cancer is characterized by locally advanced disease with varying anatomic extent as measured by the 7th edition of the American Joint Committee on Cancer (AJCC) staging system. There are no prognostic factors specifically identified in patients with stage III gastric cancer following extended lymph node dissection (D2) surgery. Materials and Methods: From 2007 to 2014, 534 patients with stage III gastric cancer underwent radical gastrectomy and D2 dissection at the Chang Gung Memorial Hospital. Patients' characteristics and the impact of adjuvant chemotherapy were analyzed using univariate and multivariate analyses to identify variables associated with overall survival (OS) and disease-free survival (DFS). Results: There were 320 deaths (60.0%) and 284 recurrences (53.2%) by the end of the study. The median OS and DFS were 30.7 months (95% confidence interval [CI]: 27.5-33.9) and 26.4 months (95% CI: 21.2-31.6), respectively. The multivariate analysis identified 7 variables that were independent prognostic factors both for OS and DFS including ratio of metastatic lymph nodes to total resection lymph nodes, carcinoembryonic antigen level, Eastern Cooperative Oncology Group performance status, gastrectomy method, vascular invasion, surgical margin, and adjuvant chemotherapy. Patients with stage IIIA-IIIC disease who received adjuvant chemotherapy had better OS and DFS outcomes than those who did not. Conclusions: Our study identified several independent prognostic factors that might help determine the appropriate counseling patients following surgical treatment. D2 surgery alone was inadequate to achieve long-term survival. As the only correctable independent prognostic factor, postoperative adjuvant chemotherapy should be recommended for eligible patients with stage III gastric cancer.

Update on the Treatment of Gastric Cancer

Gastric cancer remains a major health concern worldwide, particularly in Asia. Surgery is the only curative treatment, and D2 gastrectomy is the standard therapy for resectable cases. Several clinical trials have been conducted in Japan to achieve higher cure rates via extended surgery; however, despite higher morbidity, none demonstrated prolonged survival. Against this background, minimally invasive surgical approaches that preserve gastric function and improve postoperative quality of life have been developed in recent years. For early gastric cancer, endoscopic resection and laparoscopic gastrectomy have achieved remarkable success even for later-stage cases. Long-term outcomes have been investigated in large-scale, randomized controlled trials. In addition, robot-assisted gastrectomy is now more common in clinical practice. S-1, an anti-tumor drug, is a key agent for treating gastric cancer and has resulted in dramatic improvements in survival. For locally advanced gastric cancer, patients are usually treated with surgery and adjuvant or neoadjuvant chemotherapy, and the efficacies of various regimens have been examined in many clinical trials. For unresectable or recurrent gastric cancer, new agents such as molecular-targeted agents and immune checkpoint inhibitors have emerged as notable treatments and are now being tested in numerous clinical trials. This review provides an update on gastric cancer treatment, highlighting current individualized strategies and future perspectives.

Extensive Lymph Node Dissection Improves Survival among American Patients with Gastric Adenocarcinoma Treated Surgically: Analysis of the National Cancer Database

INTRODUCTION

The extent of lymphadenectomy in the surgical treatment of gastric cancer is a topic of controversy among surgeons. This study was conducted to analyze the American National Cancer Database (NCDB) and conclude the optimal extent of lymphadenectomy for gastric adenocarcinoma.

METHODS

The NCDB for gastric cancer was utilized. Patients who received at least a partial gastrectomy were included. Patients with metastatic disease, unknown TNM stages, R1/R2 resection, or treated with a palliative intent were excluded. Joinpoint regression was used to identify the extent of lymphadenectomy that reflects the optimal survival. Cox regression analysis and Bayesian information criterion were used to identify significant survival predictors. Kaplan-Meier was applied to study overall survival and stage migration.

RESULTS

40,281 patients of 168,377 met the inclusion criteria. Joinpoint analysis showed that dissection of 29 nodes provides the optimal median survival for the overall population. Regression analysis reported the cutoff ≥29 to have a better fit in the prognostic model than that of ≥15. Dissection of ≥29 nodes in the higher stages provides a comparable overall survival to the immediately lower stage. Nonetheless, the retrieval of ≥15 nodes proved to be adequate for staging without a significant stage migration compared to ≥29 nodes.

CONCLUSION

The extent of lymphadenectomy in gastric adenocarcinoma is a marker of improved resection which reflects in a longer overall survival. Our analysis concludes that the dissection of ≥15 nodes is adequate for staging. However, the dissection of 29 nodes might be needed to provide a significantly improved survival.

Developments in optical imaging for gastrointestinal surgery

To improve outcomes for patients with cancer, in terms of both survival and a reduction in the morbidity and mortality that results from surgical resection and treatment, there are two main areas that require improvement. Accurate early diagnosis of the cancer, at a stage where curative and, ideally, minimally invasive treatment is achievable, is desired as well as identification of tumor margins, lymphatic and distant disease, enabling complete, but not unnecessarily extensive, resection. Optical imaging is making progress in achieving these aims. This review discusses the principles of optical imaging, focusing on fluorescence and spectroscopy, and the current research that is underway in GI tract carcinomas.

Nomogram analysis and external validation to predict the risk of lymph node metastasis in gastric cancer

Aim

To identify risk factors for lymph node metastasis using a nomogram for gastric cancer patients to predict lymph node metastasis.

Results

The Chi-square test and the logistic regression showed that the Boarrmann type, preoperative CA199 level, T stage and N stage by CT scan were independent risk factors. The concordance index (C-index) was 0.786 in the internal validation of the Nomogram model. In the external validation, the C-index was 0.809, and the AUC was 0.894. The total accuracy of the prediction was 82.2%, and the false-negative rate was 5.4% with a cut-off value set at 0.109.

Materials and Methods

The study consisted of 451 patients with a histological diagnosis of gastric cancer with 0 or 1 lymph node metastasis from the Sun Yat-sen University Cancer Center as the development set, and the validation set consisted of 186 gastric cancer patients from the Sixth Affiliated Hospital of Sun Yat-Sen University. A Chi-square test and a logistic regression analysis were used to compare the clinicopathological variables and lymph node metastasis. The C-index and ROC curve were computed for comparisons of the nomogram's predictive ability.

Conclusions

We developed and validated a nomogram to predict lymph node metastasis in gastric cancer before surgery. This nomogram can be broadly applied, even in general hospitals, and is useful for decisions regarding treatment programs for patients.

Prognostic significance of the total number of harvested lymph nodes for lymph node-negative gastric cancer patients

Background

The relationship between the number of harvested lymph nodes (HLNs) and prognosis of gastric cancer patients without an involvement of lymph nodes has not been well-evaluated. The objective of this study is to further explore this issue.

Methods

We collected data from 399 gastric cancer patients between November 2006 and October 2011. All of them were without metastatic lymph nodes.

Results

Survival analyses showed that statistically significant differences existed in the survival outcomes between the two groups allocated by the total number of HLNs ranging from 16 to 22. Therefore, we adopted 22 as the cut-off value of the total number of HLNs for grouping (group A: HLNs <22; group B: HLNs≥22). The intraoperative and postoperative characteristics, including operative blood loss (P=0.096), operation time (P=0.430), postoperative hospital stay (P=0.142), complications (P=0.552), rate of reoperation (P=0.966) and postoperative mortality (P=1.000), were comparable between the two groups. T-stage-stratified Kaplan–Meier analyses revealed that the 5-year survival rate of patients at the T4 stage was better in group B than in group A (76.9% vs. 58.5%; P=0.004). An analysis of multiple factors elucidated that the total number of HLNs, T stage, operation time and age were independently correlated factors of prognosis.

Conclusions

Regarding gastric cancer patients without the involvement of lymph nodes, an HLN number ≥22 would be helpful in prolonging their overall survival, especially for those at T4 stage. The total number of HLNs was an independent prognostic factor for this population of patients.

Evolution in the surgical management of gastric cancer: is extended lymph node dissection back in vogue in the USA?

BACKGROUND

Gastric cancer remains a formidable treatment challenge. For decades, treatment consisted mostly of surgical intervention for this deadly disease. With improvements in the multi-disciplinary management of solid organ malignancies, the approach to this disease is being stepwise refined.

MAIN BODY

One of the prevalent controversies in the surgical management of gastric cancer rests on the need for adequate harvesting of lymph nodes. For decades, lymph node dissection is regarded as a staging technique useful in only upstaging the disease. The adoption of D2 lymphadenectomy has been particularly slow to mature. But with prevailing data from Asia consistently demonstrating a survival benefit from lymphadenectomy, it calls into question the notion of lymphadenectomy as being solely a staging procedure.

CONCLUSIONS

As gastric resection techniques are being better defined in western countries and surgical morbidities lowered on its execution, D2 lymphadenectomy is becoming more accepted as the new standard in the management of gastric cancer.

Comparison of short- and long-term outcomes of laparoscopic vs open resection for gastric gastrointestinal stromal tumors

AIM

To compare the short- and long-term outcomes of laparoscopic (LR) vs open resection (OR) for gastric gastrointestinal stromal tumors (gGISTs).

METHODS

In total, 301 consecutive patients undergoing LR or OR for pathologically confirmed gGISTs from 2005 to 2014 were enrolled in this retrospective study. After exclusion of 77 patients, 224 eligible patients were enrolled (122 undergoing LR and 102 undergoing OR). The demographic, clinicopathologic, and survival data of all patients were collected. The intraoperative, postoperative, and long-term oncologic outcomes were compared between the LR and OR groups following the propensity score matching to balance the measured covariates between the two groups.

RESULTS

After 1:1 propensity score matching for the set of covariates including age, sex, body mass index, American Society of Anesthesiology score, tumor location, tumor size, surgical procedures, mitotic count, and risk stratification, 80 patients in each group were included in the final analysis. The baseline parameters of the two groups were comparable after matching. The LR group was significantly superior to the OR group with respect to the operative time, intraoperative blood loss, postoperative first flatus, time to oral intake, and postoperative hospital stay (P < 0.05). No differences in perioperative blood transfusion or the incidence of postoperative complications were observed between the two groups (P > 0.05). No significant difference was found in postoperative adjuvant therapy (P = 0.587). The mean follow-up time was 35.30 ± 26.02 (range, 4-102) mo in the LR group and 40.99 ± 25.07 (range, 4-122) mo in the OR group with no significant difference (P = 0.161). Survival analysis showed no significant difference in the disease-free survival time or overall survival time between the two groups (P > 0.05).

CONCLUSION

Laparoscopic surgery for gGISTs is superior to open surgery with respect to intraoperative parameters and postoperative outcomes without compromising long-term oncological outcomes.