Implications of inadequate lymph node staging in resectable gastric cancer: a contemporary analysis using the National Cancer Data Base

Evaluation of optimum classification measures used to define textbook outcome among patients undergoing curative-intent resection of gastric cancer

BACKGROUND

Textbook outcome (TO) is a composite measure reflecting various aspects of services provided to patients with solid malignancies. We sought to evaluate the importance of various TO components previously proposed for gastric cancer.

METHODS

Prospectively maintained electronic databases of 1,743 patients treated in two academic surgical centres were reviewed. Six candidate definitions of TO were evaluated based on their ability to accurately predict patients' prognosis by Cox proportional hazards modelling.

RESULTS

TO definition combining 10 measures corresponding to complete tumour resection with an uneventful postoperative course showed the best goodness of fit by achieving the lowest values of Akaike (AIC) and Bayesian (BIC) information criteria and the best predictive performance based on the highest value of c-index. The overall median survival was significantly longer for patients with than without textbook outcome (69.0 vs 20.1 months, P < 0.001). TO maintained its prognostic value in a multivariate model controlling for age, sex, comorbidities, treatment, and tumour related variables and was associated with a 39% lower risk of death (HR 0.61, 95%CI 0.51 - 0.73, P < 0.001). Nine variables identified as predictors of TO were used to develop a nomogram showing very good correlation between the predicted and actual probability of achieving TO. The AUC of ROC obtained from the nomogram was 0.752 (95% CI 0.727 to 0.781).

CONCLUSIONS

A uniform definition of textbook outcome provides clinically relevant prognostic information and could be used in quality improvement programs for gastric cancer patients.

3D versus 2D laparoscopic distal gastrectomy in patients with gastric cancer: a systematic review and meta-analysis

BACKGROUND

While laparoscopic gastrectomy is a prominent therapeutic approach for distal gastric cancer, the clinical benefits of 3D laparoscopy over 2D laparoscopy remain unclear. We aimed to compare the clinical outcomes of 3D laparoscopy and 2D laparoscopy for distal gastric cancer resection through a systematic review and meta-analysis.

METHODS

We searched PubMed/MEDLINE, EMBASE, and Cochrane Library databases for studies published from inception through January 2023, according to the PRISMA guidelines. The MD or RR was used to compare 3D and 2D distal gastrectomy. Random-effects meta-analysis was estimated using the inverse variance and Mantel-Haenszel method for binary outcomes and the DerSimonian-Laird estimator for continuous outcomes.

RESULTS

After reviewing 559 studies, 6 manuscripts met the inclusion criteria. The analysis included 689 patients, with 348 (50.5%) in the 3D group and 341 (49.5%) in the 2D group. 3D laparoscopic gastrectomy reduces the operative time (WMD - 28.57 min, 95% CI - 50.70 to - 6.44, p = 0.011), intraoperative blood loss (WMD - 6.69 mL, 95% CI - 8.09 to - 5.29, p < 0.001), and postoperative hospital stay (WMD - 0.92 days, 95% CI - 1.43 to - 0.42, p < 0.001). There were no significant differences in time to first postoperative flatus (WMD - 0.22 days, 95% CI - 0.50 to 0.05, p = 0.110), postoperative complications (Relative Risk 0.56, 95% CI 0.22 to 1.41, p = 0.217), and the number of retrieved lymph nodes (WMD 1.25, 95% CI - 0.54 to 3.03, p = 0.172) between 3 and 2D laparoscopic distal gastrectomy.

CONCLUSION

Our study highlights the potential advantages of 3D laparoscopy in distal gastrectomy, including shorter operative time, postoperative hospital stay, and decreased intraoperative blood loss.

Separating lymph node stations by the surgeon from the gastric cancer specimen improves the quality of nodal status evaluation

BACKGROUND

In gastric cancer (GC), the pN-stage is an important prognostic factor influencing treatment. Along with the depth of invasion of the tumor, the presence of nodal metastases is one of the most important prognostic factors guiding treatment strategies in gastric cancer. Examining a small number of lymph nodes may lead to understaging of the disease; hence, it is essential for the nodal status to be precisely assessed. In this study, we explored whether dissecting lymph node stations into separate samples by the surgeon from the gastric cancer surgical specimen affects the quality of nodal status evaluation and patient outcome.

METHODS

The clinical data of 130 GC patients treated at the Helsinki University Hospital between 2016 and 2019 was reviewed. The performed operations included 59 total and 71 subtotal gastrectomies. The processing of the surgical specimen before the pathological examination was assessed from the operation records and pathology reports. The association of the number of examined lymph nodes with other variables was assessed, and multivariate survival analysis was performed to explore the independent prognostic factors in disease-specific survival.

RESULTS

Dissecting lymph node stations into separate specimens before pathological evaluation yielded a significantly greater number of examined lymph nodes compared with a specimen without intervention (median 34.5 vs 21.0, p < 0.001). The pT-stage, the pN-stage, and the extent of lymphadenectomy were identified as independent prognostic factors, whereas dissecting the specimen's lymph node stations did not associate with survival.

CONCLUSIONS

Dissecting lymph node stations into separate specimens results in a greater number of examined lymph nodes, which has the potential to lead to a more reliable pN-stage assessment.

Pattern of Distribution of Lymph Node Metastases in Individual Stations in Middle and Lower Gastric Carcinoma

(1) Background: Lymph node (LN) dissection is the cornerstone of curative treatment of GC. The pattern of distribution of LN metastases is closely related to several factors. The aim of this study is to evaluate the factors determining the distribution of nodal metastases in a population of N+ distal GC patients undergoing gastrectomy and D2 lymphadenectomy. (2) Methods: The medical charts of 162 N+ GC patients who underwent surgical resection over a 15-year period were retrospectively analyzed. Clinical, pathological and anatomical characteristics were evaluated to identify the factors affecting the patterns and prevalence of metastases in individual LN stations. (3) Results: LN metastasis is correlated with the depth of the tumor and to diffuse-type tumors. A higher number of metastatic nodes was documented in patients with middle-third tumors (8.2 ± 7.3 vs. 4.5 ± 5.0 in lower-third tumors, p = 0.0001) and in patients with tumors located on the lesser curve. Station 4 showed the highest rate of metastases (53.1%). Concerning stations 7 to 12, station 8 showed the highest metastasis rate (28.4%). Metastases at stations 1, 2, 4 and 7 to 11 were dominant in middle-third cancer, whereas stations 5 and 6 were dominant in lower-third cancers. Station 4, 5, 6, 10 and 11 metastases were dominant when the cancer was located on the greater curve, whereas stations 1, 2, 7, 8 and 12 were dominant in lesser-curve cancers. (4) Conclusions: The study documented that in patients with distal GC, the distribution of nodal metastases at individual stations is closely related to primary tumor location.

Nomogram-Based Prognostic Evaluation of Gastric Cancer Patients with Low Counts of Examined Lymph Nodes Outperforms the Predictive Ability of the 7th and 8th Editions of the American Joint Committee on Cancer Staging System

BACKGROUND

The American Joint Committee on Cancer (AJCC) staging system has limited accuracy in predicting survival of gastric cancer patients with inadequate counts of evaluated lymph nodes (LNs). We therefore aimed to develop a prognostic nomogram suitable for clinical applications in such cases.

METHODS

A total of 1511 noncardia gastric cancer patients treated between 1990 and 2010 in the academic surgical center were reviewed to compare the 7^th and 8^th editions of the AJCC staging system. A nomogram was developed for the prediction of 5-year survival in patients with less than 16 LNs evaluated (n = 546). External validation was performed using datasets derived from the Polish Gastric Cancer Study Group (n = 668) and the SEER database (n = 11,225).

RESULTS

The 8th edition of AJCC staging showed better overall discriminatory power compared to the previous version, but no improvement was found for patients with < 16 evaluated LNs. The developed nomogram had better concordance index (0.695) than the former (0.682) or latest (0.680) staging editions, including patients subject to neoadjuvant treatment, and calibration curves showed excellent agreement between the nomogram-predicted and actual survival. High discriminatory power was also demonstrated for both validation cohorts. Subsequently, the nomogram showed the best accuracy for the prediction of 5-year survival through the time-dependent ROC curve analysis in the training and validation cohorts.

CONCLUSIONS

A clinically relevant nomogram was built for the prediction of 5-year survival in patients with inadequate numbers of LNs evaluated in surgical specimens. The predictive accuracy of the nomogram was validated in two Western populations.

The order of surgery and chemotherapy matters: Multimodality therapy and stage-specific differences in survival in gastric cancer

BACKGROUND AND OBJECTIVES

Multimodality treatment improves survival for gastric cancer (GC). However, the effect of treatment sequence by stage remains unclear. We aim to compare outcomes between patients receiving neoadjuvant(neoadj) and adjuvant chemotherapy (adj).

METHODS

Nonmetastatic GC patients with clinical stage ≥ T2N0 who underwent both resection and neoadj or adj were identified using the National Cancer Database (2005-2014). Multivariable Cox regression analyses were performed on propensity score-matched (PSM) cohorts stratified by stage to compare overall survival (OS).

RESULTS

We identified 11 984 patients; 55% stage I (SI), 76% stage II (SII) and 57% stage III (SIII) received neoadj. Unadjusted analysis showed worse survival among SI neoadj patients (hazard ratio [HR] 1.195, confidence interval [CI] 1.04-1.38) and improved survival for SII (HR 0.93 CI 0.87-0.998) and SIII (HR 0.75, CI 0.68-0.84). After PSM, SI patients with neoadj had worse OS with increased risk of death compared to Adj (HR 1.186, CI 1.004-1.402). SII patients had no difference in OS (HR 0.98, CI 0.91-1.07) and SIII patients had improved OS (HR 0.78, CI 0.69-0.90).

CONCLUSIONS

In patients who received surgery and chemotherapy, the benefit of neoadj was limited to SIII with worse survival for SI. A clinical trial to examine the optimal sequence of chemotherapy is warranted.

Superior pancreatic lymphadenectomy with portal vein priority via posterior common hepatic artery approach in laparoscopic radical gastrectomy

BACKGROUND

D2 lymph node dissection for advanced gastric cancer is advocated, and station 8p lymph node should be considered in selected patients, which is, however, technically difficult.

AIM

To introduce a new and easy-to-perform procedure for dissection of the lymph nodes superior to the pancreas.

METHODS

A series of patients who underwent laparoscopic gastrectomy for gastric cancer were retrospectively included with utilization of a new procedure for superior pancreatic lymphadenectomy (LND) with portal vein priority via the posterior common hepatic artery approach (SPLD-PPPH) based on a newly defined portal triangle. The surgical outcome of the patients, as well as the efficacy and safety of SPLD-PPPH are reported.

RESULTS

A total of 51 patients were included with most of them being male (n = 34, 66.7%). According to the 8^th edition of AJCC TNM staging, there were four (7.8%) patients in stage I, 13 (25.5%) in stage II, 33 (64.7%) in stage III and one (2.0%) in stage IV. The average duration for LND was about 1 h (67.7 ± 6.9 min). After surgery, four patients developed morbidities, but all were treated successfully with no perioperative mortality. Among the 51 patients included, the percentage of patients who had lymph node metastasis at station 8p was 9.8%. Of note, with a total of 14 lymph nodes harvested at station 8p, the incidence of nodal metastasis was 14.3%.

CONCLUSION

About one in 10 patients with advanced gastric cancer had nodal metastasis at station 8p. The new approach of SPLD-PPPH is safe and effective for D2+ LND during laparoscopic radical gastrectomy.

The development and external validation of a nomogram predicting overall survival of gastric cancer patients with inadequate lymph nodes based on an international database

BACKGROUND

Inadequate sampling of lymph nodes could lead to stage migration and indicate a poor prognosis for gastric cancer after curative surgery. Some emerging novel predictors and the application of a nomogram could increase the accuracy of survival prediction.

METHODS

An international database regarding gastric cancer was employed as the primary cohort. The patients with inadequate (< 30) lymph nodes (LN) were analyzed by Cox proportional hazards regression. Based on the selected model, a nomogram was plotted and calibrated against an external validation database.

RESULTS

A total of 1109 patients were included in the primary cohort, and there were 6584 patients in the validation cohort. There were significant differences regarding the clinical characteristics between the two cohorts. The model containing age, T stages, N stages, metastatic lymph nodes (mLN), and the number of total LN retrieved (TLN) showed superiority over the conventional TNM stages. Harrell's concordance index of the nomogram and TNM stages was 0.744 and 0.717, respectively. The external validation demonstrated a good concordance with the nomogram-predicted survival.

CONCLUSIONS

The nomogram including age, T stages, N stages, mLN, and TLN had a better accuracy than the conventional TNM staging system in predicting overall survival for gastric cancer patients with inadequate (< 30) LN.

Time to Rethink Upfront Surgery for Resectable Intrahepatic Cholangiocarcinoma? Implications from the Neoadjuvant Experience

BACKGROUND

While surgery is a mainstay of curative-intent treatment for patients with intrahepatic cholangiocarcinoma (IHC), the role of neoadjuvant therapy (NT) has not been well-established. We sought to describe trends in NT utilization, characterize associated factors, and evaluate association with overall survival (OS).

METHODS

Retrospective cohort study of 4456 surgically resected IHC patients within National Cancer Data Base (2006-2016). NT included chemotherapy alone and/or (chemo)radiation. Descriptive statistics used to describe the cohort. Multivariable hierarchical logistic regression models were used to examine factors associated with NT administration. Analyses conducted comparing OS among upfront surgery patients and NT patients using propensity matching using nearest-neighbor methodology and adjustment using inverse probability of treatment weighting (IPTW). Association between NT and risk of death evaluated using multivariable Cox shared frailty modeling.

RESULTS

Utilization of NT did not significantly increase over time (11%-2006 to 16%-2016, trend test p = 0.07) but did increase among patients with clinical nodal involvement (cN+, 13% to 36%, p = 0.002). Factors associated with NT use include cN+ disease (odds ratio [OR] 1.68, 95% confidence interval [CI] 1.31-2.15) and advanced clinical T stage: T2 (OR 1.65, 95% CI 1.33-2.06); T3 (OR 1.51, 95% CI 1.13-2.02). After propensity matching, NT associated with a 23% decreased risk of death relative to upfront surgery (hazard ratio [HR] 0.77, 95% CI 0.61-0.97). Findings were similar after IPTW (HR 0.83, 95% CI 0.78-0.88).

CONCLUSIONS

NT is increasingly used for the management of IHC patients with characteristics indicating aggressive tumor biology and is associated with decreased risk of death. These data suggest need for prospective studies of NT in management of patients with potentially resectable IHC.

Redefining High-Volume Gastric Cancer Centers: The Impact of Operative Volume on Surgical Outcomes

BACKGROUND

Performance of technically complex surgery at high-volume (HV) centers is associated with improved outcomes.

OBJECTIVE

The aim of this study was to assess whether hospital gastrectomy volume is associated with surgical outcomes, and what threshold of case volume meaningfully impacts surgical outcomes.

METHODS

We conducted a retrospective review of adult NCDB patients with gastric adenocarcinoma undergoing gastrectomy between 2004 and 2015. A multivariable Cox proportional hazards model with restricted cubic splines was used to examine the association of annual hospital gastrectomy volume and overall survival. Bootstrap simulation was used to estimate the cut-point corresponding to maximum change in log hazard ratio. Hospitals were divided into HV (≥ 17 cases/year) and low-volume (LV; < 17 cases/year) groups. We examined the relationship between volume groups and adequate nodal examination, R0 resection, unplanned readmission, and 30- and 90-day mortality.

RESULTS

Our cohort consisted of 29,559 patients (7.8% treated at an HV center). Treatment at an HV center was associated with an increased likelihood of adequate nodal examination [odds ratio (OR) 2.12, 95% confidence interval (CI) 1.94-2.32] and R0 resection among patients with cardia tumors (OR 1.42, 95% CI 1.07-1.88). Patients treated at HV centers had decreased 30- and 90-day postoperative mortality, which was more pronounced in those undergoing total gastrectomy.

CONCLUSIONS

Treatment at an HV gastrectomy center is associated with improved surgical outcomes. Our study identified 17 cases/year as a clinically meaningful distinction between HV and LV centers. This definition of an HV center should be considered when evaluating regionalization of gastric cancer care to improve patient outcomes.

Intraoperative Molecular Imaging Utilizing a Folate Receptor-Targeted Near-Infrared Probe Can Identify Macroscopic Gastric Adenocarcinomas

PURPOSE

Current methods of assessing disease burden in gastric adenocarcinoma are imperfect. Improved visualization during surgery with intraoperative molecular imaging (IMI) could improve gastric adenocarcinoma staging and guide surgical decision-making. The goal of this study was to evaluate if IMI with a folate receptor-targeted near-infrared fluorescent agent, OTL38, could identify gastric adenocarcinomas during surgery.

PROCEDURES

Five patients were enrolled in an IMI clinical trial. Patients received a folate receptor-targeted near-infrared dye (OTL38) 1.5-6 h prior to surgery. During staging laparoscopy and gastric resection, IMI was utilized to identify the primary tumor and any fluorescent lymph nodes. Resected tumors were analyzed for folate receptor alpha (FRα) and CD68 expression using immunohistochemistry. Microscopic OTL38 accumulation was examined with immunofluorescence.

RESULTS

Four out of five patients underwent total or subtotal gastrectomy; one had a staging laparoscopy only. All four patients who underwent gastric resection had invasive gastric adenocarcinoma; three had fluorescent tumors, mean tumor to background ratio (TBR) 4.1 ± 2.9. The one patient with a non-fluorescent tumor had a T1a tumor with two 0.4 cm tumor foci within a larger polyp. In each case with a fluorescent tumor, the fluorescence was evident from the exterior of the stomach. Two of the fluorescent tumors had modest FRα expression and no CD68 expression. One fluorescent tumor had high CD68 expression and no FRα expression.

CONCLUSIONS

Intraoperative molecular imaging of gastric adenocarcinoma with OTL38 is feasible. Further studies should evaluate the clinical utility of this technique.

Prognostic impact of anatomical extent of metastatic lymph node on gastric cancer: a propensity score matching study

PURPOSE

Current gastric cancer staging systems overlook the anatomic extent of metastatic lymph nodes (AEMLNs). This study aimed to analyze the prognostic impact of AEMLNs on gastric cancer (GC).

METHODS

GC patients with metastatic lymph nodes (MLNs) undergoing curative surgery were retrospectively reviewed and assigned to perigastric (MLNs in station 1-6, PG) and extraperigastric group (7-12, with or without MLNs in PG area, EPG). Overall survival (OS), disease-free survival (DFS) and recurrence patterns were compared before and after 1:1 propensity score matching (PSM).

RESULTS

662 patients were enrolled, 341 (51.5%) and 321 (48.5%) of whom were in the PG and EPG, respectively. After PSM (n = 195), EPG showed poorer 5-year OS (43.4% vs 54.5%, p = 0.014) and DFS (65.0% vs 73.4%, p = 0.068) than PG. EPG had higher incidence of peritoneal recurrence (PR) than PG (19.4% vs 7.4%, p = 0.002). Multivariate analysis identified AEMLNs as prognostic factor for OS [HR = 1.409, 95% confidence interval (CI) 1.062-1.868), DFS (HR = 1.600, 95% CI 1.059-2.416) and PR (HR = 3.708, 95% CI 1.685-8.160).

CONCLUSIONS

The anatomic extent of metastatic lymph nodes has an independent prognostic role for GC. Including this element may improve the accuracy of current staging systems.

Multidisciplinary Approach in Improving Survival Outcome of Early-Stage Gastric Cancer

BACKGROUND

The necessity of extensive lymph node (LN) dissection/examination and adjuvant therapy for patients with early gastric cancer (EGC, Tis-T1, any N) remains controversial. We aim to refine treatment recommendations for patients with EGC through a reflective analysis for the survival gap between Eastern and Western countries.

METHODS

EGC patients diagnosed between 2004 and 2014 were identified from the National Cancer Database (NCDB) and a large medical center in China. Adequate LN yield was defined as ≥25 LNs examined.

RESULTS

In the US cohort, 14.4% of (1104/7641) patients with EGC had ≥25 LNs examined. The 5-y overall survival (OS) was significantly better than those with <25 LNs (78.9% versus 68.5%, P < 0.001). Examination of ≥25 LNs was an independent predictor of better OS after adjusting all known prognostic factors. Patients with ≥25 LNs examined had significantly higher chance of having LN-positive disease compared to patients with <25 LNs (14.9% versus 10.7%, P < 0.001). A similar stage migration phenomenon was observed in Chinese cohort (LN positive: 25.2% versus 18.4% in ≥25 LNs and <25 LNs examined group, respectively, P = 0.02). In the US cohort, adjuvant therapy was associated with a significant survival benefit for LN-positive patients (5-y OS: 71.0% versus 43.0% for with/without adjuvant therapy, respectively, P < 0.001) but not in LN-negative patients (5-y OS: 71.2% versus 71.5%, P = 0.90).

CONCLUSIONS

Adequate lymphadenectomy and LN examination are critical components of EGC management. Adjuvant therapy should be strongly encouraged for all EGC patients with LN-positive disease in the United States.

Clinicopathologic factors associated with recurrence and long-term survival in node-negative advanced gastric cancer patients

BACKGROUND

despite a better prognosis in node-negative advanced gastric cancer (GC), a proportion of patients have a tumor recurrence within five years and eventually die due to cancer-related causes. The present study aimed to evaluate the predictive factors of tumor recurrence and long-term survival in node-negative advanced GC.

METHODS

a total of 646 node-negative advanced GC patients who underwent a curative gastrectomy in our institution were included in the study. The impact of different clinicopathologic factors on tumor recurrence and overall survival were analyzed.

RESULTS

tumor recurrences were observed in 181 patients and the cumulative recurrence rate at two-years and five-years were 50.8% and 86.2%, respectively. Lymphovascular invasion, advanced T stage (T3-T4) and an inadequate number of retrieved lymph nodes (LNs) were independent predictive factors of tumor recurrence in node-negative advanced GC. Older age, an upper 1/3 tumor, lymphovascular invasion, infiltration growth pattern (INFγ) and the depth of tumor invasion (T4 stage) were independently associated with long-term survival. With regard to node-negative patients with ≥ 15 retrieved LNs, infiltration growth pattern (INFγ) and advanced T stage (T3-T4) were independent risk factors for both tumor recurrence and long-term survival.

CONCLUSION

in addition to lymphovascular invasion, inadequate RLNs and advanced T stage, the prognostic significance of infiltration growth pattern in node-negative advanced GC was especially emphasized. These risk factors should be considered when selecting candidates for adjuvant chemotherapy and postoperative surveillance.

Comparison of short-term surgical outcome between 3D and 2D laparoscopy surgery for gastrointestinal cancer: a systematic review and meta-analysis

BACKGROUND

Three-dimensional (3D) laparoscopic surgery is becoming more popular with the development of laparoscopic devices. The objective of this study was to explore whether the 3D imaging system could improve surgical outcomes of laparoscopic surgery for gastrointestinal cancer compared with the 2D imaging system.

METHODS

Systematic literature search was performed using PubMed and Embase databases and relevant data were extracted. Surgical quality, postoperative complications, and postoperative recovery between 3D and 2D laparoscopic surgery groups were compared using a fixed or random effect model.

RESULTS

A total of 12 studies involving 1456 patients (3D group 683 patients and 2D group 773 patients) were included in this meta-analysis. The results indicated that mean operation time was significantly shorter in 3D group than in 2D group (WMD, - 9.08; 95% CI, - 14.77, - 3.40; P = 0.002; I² = 70.3%), especially for gastric cancer patients (WMD, - 14.61; 95% CI, - 26.00, - 3.23, P = 0.012; I² = 74.1%). In addition, 3D laparoscopic surgery for gastric cancer had an advantage than 2D group in reducing the amount of intraoperative blood loss (WMD, - 13.60, 95% CI, - 21.48, - 5.72; P = 0.001; I² = 0%). The number of retrieved lymph nodes in 3D group was not significantly different from that in 2D group, regardless of laparoscopic gastrectomy (WMD, 1.10; 95% CI, - 0.67, 2.88; P = 0.222; I² = 18.8%) and laparoscopic colorectal surgery (WMD, 0.55, 95% CI; - 1.99, 3.09; P = 0.671; I² = 76.9%). In addition, there was no significant difference between 3D and 2D laparoscopic surgery for postoperative complications and postoperative recovery.

CONCLUSION

Main advantages of 3D laparoscopic gastrectomy for gastric cancer were that it could shorten the operation time and reduce the amount of intraoperative blood loss. However, 3D laparoscopic surgery had no obvious advantage over 2D laparoscopic surgery for colorectal cancer patients.

The relationship between the number of examined lymph nodes and the efficacy of chemotherapy for gastric cancer

BACKGROUND

The purpose of this research was to investigate the relationship between the number of examined lymph nodes (eLNs) and the prognosis.

METHODS

A retrospective examination of reports and studies carried out at two institutions was conducted. According to TNM stages, the relationship between the number of eLNs and the prognosis was analyzed.

RESULTS

The 5-year disease-specific survival (DSS) of all enrolled patients was 66.3%. A multivariate analysis showed the type of gastrectomy, histologic type, perineural invasion, pT stage, pN stage, chemotherapy and eLNs to be independent prognostic markers. Additionally, with the exception of patients with stage I disease, the 5-year DSS of patients who had < 25 eLNs removed had a higher risk of having a worst prognosis compared to patients who had ≥ 25 eLNs removed. Through this study, a hypothetical TNM staging system was obtained for predicting the prognosis according to the number of eLNs. Chemotherapy was able to improve the prognosis of patients with stage III and < 25 eLNs in stage II.

CONCLUSIONS

Extended lymphadenectomy with a new goal of dissecting 25 LNs for the evaluation of stage II-III cancer cases is recommended. Our hypothetical TNM staging system may be able to stratify the risk more accurately compared to the current AJCC 8th system. Chemotherapy can improve the prognosis in advanced gastric cancer, but its benefit may be affected by the surgical quality.

Insufficient lymph node assessment in gastric adenocarcinoma

BACKGROUND

This study aimed to investigate the sufficient (≥ 16) lymph node assessment in 449 patients with gastric adenocarcinoma and literature review.

METHODS

Four hundred and forty-nine patients with pathologically confirmed locoregional invasive gastric adenocarcinoma from 2004 to 2013 were included. A standard surgical resection was performed for all the patients with (n = 16) or without (n = 433) neoadjuvant treatment.

RESULTS

In this study, 301 men and 148 women with a median age of 58 (range 21-88) years were included. The median total numbers of examined lymph nodes were 9 (range 0-55). Ninety-five patients (21.2%) had adequate (≥ 16) lymph node examination, and 70 patients (15.6%) had no examined lymph nodes. In univariate analysis, total or near total gastrectomy (P <  0.001), advanced node stage (P < 0.001), primary tumor size > 6 cm (P < 0.001), and the presence of perineural invasion (P = 0.039) were associated with more average number of examined lymph nodes. On multivariate analysis, node stage (P < 0.001) and type of surgery (P = 0.008) were independent predictive factors.

CONCLUSION

In this study, approximately one in five patients with gastric adenocarcinoma had sufficient lymph node assessment. More studies are suggested for identifying a true inadequate lymph node dissection from insufficient lymph node assessment.

Retrieved lymph nodes from different anatomic groups in gastric cancer: a proposed optimal number, comparison with other nodal classification strategies and its impact on prognosis

Background

The optimal number of retrieved lymph nodes (LNs) in gastric cancer (GC) is still debatable and previous studies proposing new classification alternatives mostly focused on the number of retrieved LNs without proper consideration on the anatomic nodal groups’ location. Here, we assessed the impact of retrieved LNs from different nodal location groups on the survival of GC patients.

Methods

Stage I–III gastric cancer patients who had radical gastrectomy were investigated. LN grouping was determined according to the 13th edition of the JCGC. The optimal cut-off values of retrieved LNs in different LN groups (Group 1 and 2) were calculated, based on which a proposed nodal classification (rN) simultaneously accounting the optimal number and location of retrieved LNs was proposed. The performance of rN was then compared to that of LN ratio, log-odds of metastatic LNs (LODDs) and the 8th edition of the Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) N classification.

Results

The optimal cut-off values for Group 1 and 2 were 13 and 9, respectively. The 5-year overall survival (OS) was higher for patients in retrieved Group 1 LNs > 13 (vs. Group 1 LNs ≤ 13, 63.2% vs. 57.9%, P = 0.005) and retrieved Group 2 LNs > 9 (vs. Group 2 LNs ≤ 9, 72.5% vs. 60.7%, P = 0.009). Patients staged as pN0–3b were sub classified using this Group 1 and 2 nodal analogy. The OS of pN0–N2 patients in retrieved Group 1 LNs > 13 or Group 2 LNs > 9 were superior to those in retrieved Group 1 LNs ≤ 13 and Group 2 LNs ≤ 9 (All P < 0.05); except for pN3 patients. The rN classification was formulated and demonstrated better 5-year OS prognostication performance as compared to the LNR, LODDs, and the 8th UICC/AJCC N staging system.

Conclusions

The retrieval of > 13 and > 9 LNs for Group 1 and Group 2, respectively, could represent an alternative lymph node retrieval approach in radical gastrectomy for more precise survival prognostication and minimizing staging migration, especially if > 16 LNs is found to be difficult.

Feasibility of laparoscopy gastrectomy for gastric cancer in the patients with high body mass index: A systematic review and meta-analysis

The aim of this study was to evaluate the impact of high body mass index (BMI) on surgical outcome of laparoscopic gastrectomy for gastric cancer (GC). Systematic literature search was performed using PubMed and Embase databases. The relevant data were extracted, and surgical outcomes and postoperative complications were compared between BMI≥25 kg/m² and BMI<25 kg/m² group using a fixed effect model or random effect model. 16 studies, with a total of 9572 GC patients, were included in this meta-analysis. The results indicated that operation time was significantly longer (WMD:16.22, 95% CI: 14.10-18.34, P < 0.001; I² = 0%) and the number of lymph nodes retrieved was significantly fewer (WMD:-2.11, 95%CI: -3.14, -1.07, P < 0.001; I² = 64.0%) in high BMI patients than in other patients. In addition, the amount of intraoperative blood loss was significantly larger in high BMI patients (WMD: 23.43, 95%CI: 20.05-26.81, P < 0.001; I² = 40.3%). Compared with non-high BMI patients, overweight and obese patients had a higher risk of postoperative complications (RR:1.26, 95%CI: 1.11-1.43, P < 0.001; I² = 39.1%), especially for wound infection (RR:1.62, 95%CI: 1.15-2.29, P < 0.01; I² = 18.8%) and postoperative ileus (RR:1.80, 95% CI: 1.05-3.09, P < 0.05; I² = 0%). However, there was no significant difference between two patient groups for postoperative recovery, major surgery-related complications (eg: anastomotic leakage, pancreatic fistula and intra-abdominal bleeding) and postoperative mortality. Despite increased technical challenge and risk of postoperative complications, the majority of these complications may be minor and cured. Laparoscopic gastrectomy for GC was a feasible and safe procedure even for high BMI patients.

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.

Does high body mass index negatively affect the surgical outcome and long-term survival of gastric cancer patients who underwent gastrectomy: A systematic review and meta-analysis

BACKGROUND

Whether high body mass index (BMI) was associated with increased postoperative complications and unfavorable prognosis of gastric cancer (GC) patients remain controversial. In the present study, we performed a systematic review and meta-analysis to evaluate the impact of high BMI on surgical outcome, postoperative complications and long-term survival of GC patients.

METHODS

The related studies were identified by searching PubMed and Embase databases. According to the BMI, all GC patients were classified into BMI ≥25 kg/m² group and BMI <25 kg/m² group. The relevant data was extracted and pooled effect size was assessed using a fixed effect model or random effect model.

RESULTS

A total of 36 relevant studies involving 30,642 GC patients were included in this meta-analysis. The results indicated that high BMI patients had longer operation time, fewer number of retrieved lymph nodes and larger amount of intraoperative blood loss than other patients, regardless of open gastrectomy or laparoscopic gastrectomy. In addition, the risk of postoperative complications was significantly higher in the patients with BMI ≥25 kg/m² than in those with BMI <25 kg/m², especially for infectious complications. However, high BMI had no negative impact on postoperative mortality and long-term survival of GC patients.

CONCLUSION

Despite the increased surgical difficulty and postoperative complications, high BMI was not associated with the prognosis of GC patients. To reduce the risk of postoperative complications, more meticulous operation technique and improved perioperative management should be necessary for high BMI patients.

Comorbidity Assessment in the National Cancer Database for Patients With Surgically Resected Breast, Colorectal, or Lung Cancer (AFT-01, -02, -03)

PURPOSE

Accurate comorbidity measurement is critical for cancer research. We evaluated comorbidity assessment in the National Cancer Database (NCDB), which uses a code-based Charlson-Deyo Comorbidity Index (CCI), and compared its prognostic performance with a chart-based CCI and individual comorbidities in a national sample of patients with breast, colorectal, or lung cancer.

PATIENTS AND METHODS

Through an NCDB Special Study, cancer registrars re-abstracted perioperative comorbidities for 11,243 patients with stage II to III breast cancer, 10,880 with stage I to III colorectal cancer, and 9,640 with stage I to III lung cancer treated with definitive surgical resection in 2006-2007. For each cancer type, we compared the prognostic performance of the NCDB code-based CCI (categorical: 0 or missing data, 1, 2+), Special Study chart-based CCI (continuous), and 18 individual comorbidities in three separate Cox proportional hazards models for postoperative 5-year overall survival.

RESULTS

Comorbidity was highest among patients with lung cancer (13.2% NCDB CCI 2+) and lowest among patients with breast cancer (2.8% NCDB CCI 2+). Agreement between the NCDB and Special Study CCI was highest for breast cancer (rank correlation, 0.50) and lowest for lung cancer (rank correlation, 0.40). The NCDB CCI underestimated comorbidity for 19.1%, 29.3%, and 36.2% of patients with breast, colorectal, and lung cancer, respectively. Within each cancer type, the prognostic performance of the NCDB CCI, Special Study CCI, and individual comorbidities to predict postoperative 5-year overall survival was similar.

CONCLUSION

The NCDB underestimated comorbidity in patients with surgically resected breast, colorectal, or lung cancer, partly because the NCDB codes missing data as CCI 0. However, despite underestimation of comorbidity, the NCDB CCI was similar to the more complete measures of comorbidity in the Special Study in predicting overall survival.

Trends in perioperative outcomes of hospitals performing major cancer surgery

BACKGROUND AND OBJECTIVES

Cancer surgery outcomes at National Cancer Institute-designated cancer centers (NCI-CCs) have been shown to vary, and have not been uniformly better than outcomes among non-NCI-CCs. We aimed to assess whether NCI-CCs have improved their short-term outcomes over time and whether variation across these centers has changed.

METHODS

Patients who underwent colectomy, esophagectomy, hepatectomy, pancreatectomy, and proctectomy for cancer were identified from the 2010 to 2016 American College of Surgeons' National Surgical Quality Improvement Program registry. Hospital trends in risk-adjusted, smoothed observed-to-expected ratios were assessed to evaluate improvement and variation in perioperative complications, stratified by NCI-CC status.

RESULTS

Complications occurred in 18.8% of 204 732 patients who underwent major cancer operations at 645 hospitals, and complications occurred in 19.9% of 60,903 patients at 54 NCI-CCs studied. More NCI-CCs than non-NCI-CCs improved over the period (85.2% vs 58.4%, P < 0.001; relative risk [RR] 1.46, 95% confidence interval [CI], 1.28-1.66); this remained significant after adjusting for years of participation (RR 1.33, 95% CI, 1.17-1.51). Variation in performance remained unchanged over time.

CONCLUSION

NCI-CCs were detected to have improved over a contemporary seven-year period and to have improved more than non-NCI-CCs. However, NCI-CCs do not uniformly outperform non-NCI-CCs, and variation in perioperative outcomes remains, warranting continued quality improvement efforts targeting cancer-specific operations.

Gastric cancer in Alaska Native people: A cancer health disparity

AIM

To evaluate recent trends in gastric cancer incidence, response to treatment, and overall survival among Alaska Native (AN) people.

METHODS

A retrospective analysis of the Alaska Native Medical Center patient database was performed. Patient history, clinical, pathological, response to treatment and patient outcomes were collected from one-hundred and thirty-two AN gastric cancer patients. The Surveillance, Epidemiology and End Result database 18 was used to collect comparison United States non-Hispanic White (NHW) and AN gastric cancer patient data between 2006-2014.

RESULTS

AN gastric cancer patients have a higher incidence rate, a poorer overall survival, and are diagnosed at a significantly younger age compared to NHW patients. AN patients differ from NHW patients in greater prevalence of non-cardia, diffuse subtype, and signet ring cell carcinomas. AN females were more likely to be diagnosed with later stage cancer, stage IV, compared to AN males. Diminished overall survival was observed among AN patients with increasing stage, O+ blood type, < 15 lymph nodes examined at resection, and no treatment. This study is the first report detailing the clinicopathologic features of gastric cancer in AN people with outcome data.

CONCLUSION

Our findings confirm the importance of early detection, treatment, and surgical resection for optimizing AN patient outcomes. Further research on early detection markers are warranted.

Surgical management of periampullary adenocarcinoma: defining an optimal prognostic lymph node stratification schema

Background: Lymph node (LN) metastasis is a strong predictor of unfavorable prognosis for patients with periampullary adenocarcinoma after surgical resection. We sought to assess the prognostic performance of several LN staging systems, including American Joint Committee on Cancer (AJCC)/ International Union Against Cancer (7th edition) N stage, the total number of LN (TLN), the number of metastatic LN (MLN), the lymph node ratio (LNR) and the log odds of MLNs (LODDS), in patients with periampullary adenocarcinoma after surgical resection and identify the optional LN staging system to accurately stratify patients with different prognoses. Methods: We retrospectively analyzed 205 patients with periampullary adenocarcinoma after surgical resection. The predictive effects of several LN staging systems on overall survival (OS) and progression free survival (PFS) for all included patients and patients with more than 12 TLNs examined were evaluated and compared using the time-dependent receive operating characteristic (ROC) curve and decision curve analysis (DCA), respectively. Results: Eighty-nine patients (43.4%) had LN metastasis and their survival was not significantly decreased compared with patients without LN metastasis. LODDS and LNR were able to stratify patients into various subgroups with significant differences of both OS and PFS. When assessed using ROC curve and DCA, LODDS outperformed LNR and other LN staging systems in predicting OS and PFS. In addition, when analyzed in patients with more than 12 TLNs examined, LODDS had a higher value of area under ROC curve (AUC) and showed better performance of DCA. Conclusion: LODDS performs better than other LN staging systems in predicting OS and PFS for patients with periampullary adenocarcinoma after surgical resection. Adequate LN dissection is necessary for curative surgery, as well as to achieve a more accurate staging of the disease and a more precise prediction of survival for these patients.

Nomograms predict long-term survival for patients with periampullary adenocarcinoma after pancreatoduodenectomy

BACKGROUND

The prognosis of patients with periampullary adenocarcinoma after pancreatoduodenectomy is diverse and not yet clearly illustrated. The aim of this study was to develop a nomogram to predict individual risk of overall survival (OS) and progression-free survival (PFS) in patients with periampullary adenocarcinoma after pancreatoduodenectomy.

METHODS

A total of 205 patients with periampullary adenocarcinoma after pancreatoduodenectomy were retrospectively included. OS and PFS were evaluated by the Kaplan-Meier method. Two nomograms for predicting OS and PFS were established, and the predictive accuracy was measured by the concordance index (Cindex) and calibration plots.

RESULTS

Lymph node ratio (LNR), carbohydrate antigen 19-9 (CA19-9) and anatomical location were incorporated into the nomogram for OS prediction and LNR, CA19-9; anatomical location and tumor differentiation were incorporated into the nomogram for PFS prediction. All calibration plots for the probability of OS and PFS fit well. The Cindexes of the nomograms for OS and PFS prediction were 0.678 and 0.68, respectively. The OS and PFS survival times were stratified significantly using the nomogram-predicted survival probabilities.

CONCLUSIONS

The present nomograms for OS and PFS prediction can provide valuable information for tailored decision-making for patients with periampullary adenocarcinoma after pancreatoduodenectomy.

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.

The retrieval of at least 25 lymph nodes should be essential for advanced gastric cancer patients with lymph node metastasis: A retrospective analysis of single-institution database study design: Cohort study

BACKGROUND

Recently, increased evidence have shown that the better prognosis of gastric cancer (GC) patients was associated with the larger number of retrieved lymph nodes (RLNs), but the optimal number of RLNs remains controversial. In the present study, we investigated whether adequate LN retrieval (≥15) was necessary to evaluate the prognosis of patients and attempted to propose an appropriate cutoff-point for the number of RLNs.

METHODS

We reviewed 2246 GC patients who underwent radical gastrectomy in our research institution between January 1986 and January 2008. All patients were divided into several groups based on the number of RLNs. The prognostic outcomes of different patient groups were compared and clinicopathologic features were analyzed.

RESULTS

In the present study, our results indicated that ≥15 RLNs showed a better survival outcome than inadequate LN retrieval (<15), regardless of the node-negative or node-positive GC patients (P < 0.001). For the more advanced GC patients (T2-T4 stage, N1-N3 stage, and stage II-stage III), the retrieval of 25-29 LNs could provide a better survival benefit compared with <25 or ≥30 RLNs (P < 0.05). In addition, for the patients who underwent proximal or total gastrectomy, the superior prognosis was still observed in the patient group with 25-29 RLNs.

CONCLUSION

The minimal goal of 15 RLNs may not be enough to accurately evaluate prognosis of all patients and at least 25 RLNs should be necessary for advanced GC patients with lymph node metastasis.

Survival Analysis with Extended Lymphadenectomy for Gastric Cancer: Removing Stage Migration from the Equation

The survival benefit of an extended versus standard lymphadenectomy for gastric cancer (GC) is often attributed to upstaging when more lymph nodes (LNs) are removed, i.e., stage migration. An extended lymphadenectomy is defined as 30 or more LNs examined, a surrogate for a D2 dissection. The aim of this study is to examine whether the survival benefit of extended lymphadenectomy persists when stage migration is not possible. The National Cancer Data Base was queried to identify patients with pathologic N3 (pN3, ≥7 positive LNs) gastric adenocarcinoma. Overall survival (OS) was compared by extent of lymphadenectomy (7–14, 15–29, and ≥30 LN) and stratified by Tstage. Of 2101 pN3 patients, 419 (19.9%) had 7 to 14 LNs examined, 1164 (55.4%) had 15 to 29 LNs examined, and 518 (24.7%) had ≥30 LNs examined. Unadjusted three-year OS in the entire cohort was 24.6, 27.3, 30.5 per cent for 7 to 14 LNs, 15 to 29 LNs, and ≥30 LNs, respectively (P = 0.003). On adjusted survival analysis by stage for patients with pT1-T2N3 disease, removing ≥30 LNs significantly improved OS compared with removing 7 to 14 LNs (hazard ratio [HR] 2.45, 95% confidence interval = 1.25–4.82, P = 0.009). Extended lymphadenectomy may confer a survival benefit in select patients with pT1N3 and pT2N3 GC, highlighting the importance of the number of LNs examined rather than stage migration on survival. For the majority of the N3 population, pT3-pT4, the extent of lymphadenectomy did not significantly improve the OS.

Validation of the 8th Edition of the AJCC TNM Staging System for Gastric Cancer using the National Cancer Database

BACKGROUND

The 8th edition AJCC gastric cancer staging manual was refined using Japanese and Korean data from the International Gastric Cancer Association (IGCA). This study evaluated the eighth edition's validity for U.S.

POPULATIONS

METHODS

National Cancer Database (NCDB) was used to obtain data on gastric cancer patients diagnosed from 2004 to 2008 who underwent surgery and to examine differences in stage grouping and survival between AJCC 7th and 8th editions. Discrimination of models derived from NCDB and IGCA data was compared.

RESULTS

Of 12,041 patients, median age was 65, 57.6% were male, median lymph nodes retrieved was 2 (0-76), 30.9% underwent distal/partial gastrectomy, and 49.8% received no adjuvant treatment. The 8th edition differed in that T1-T3 disease was upstaged with N3b, T4aN3a was downstaged from IIIC to IIIB, and T4bN0 and T4aN2 were downstaged from IIIB to IIIA. These changes resulted in increased patients in IIIA (1436 in the 7th edition to 2310 in the 8th) and IIIB (1737-1896) and decreased in IIIC (2100-1067). This also resulted in lower median survival for IIIA (28.7-25.0 months), IIIB (19.6-17.4), IIIC (13.7-11.8). The concordance index for the 8th edition applied to NCDB data was 0.719 [95% confidence interval (CI) 0.703-0.734), which is comparable to that for the 8th edition developed from IGCA data (0.775, 95% CI 0.770-0.780) and the 7th edition applied to NCDB data (0.720, 95% CI 0.704-0.735).

CONCLUSIONS

The 8th edition is valid for U.S. populations, showing clear separation of data with preservation of group order.

Prognostic relevance of lymph node status for patients with ampullary adenocarcinoma after radical resection followed by adjuvant treatment

PURPOSE

Attempts have been made to revise the nodal stage due to simplicity of current N staging system in ampullary adenocarcinoma. However, because of the disease rarity, there have only been a few studies assessing the prognostic impact of lymph node (LN) parameters.

METHODS

We retrospectively analyzed 120 patients who underwent radical resection followed by adjuvant chemoradiotherapy for ampullary adenocarcinoma. The effect of LN parameters (number of total harvest LNs, number of metastatic LN (MLN), lymph node ratio (LNR), and log odds of positive LNs (LODDS)) on overall survival (OS), locoregional relapse-free survival (LRFS) and distant metastasis-free survival were evaluated. Cutoff points of MLN, LNR and LODDs were determined using maximal χ² method.

RESULTS

Fifty-seven patients (48%) were staged as pN1 and their survival was not significantly decreased compared with pN0 patients. There was also no significant difference between patients with MLN 0 vs. 1. In univariate analyses, MLN (0-1 vs. ≥2), LNR (≤17% vs. >17%) and perineural invasion were common prognosticators for OS and LRFS. Distant metastasis-free survival was not influenced by LN status. In addition, multivariate analysis revealed that among the LN parameters, LNR was able to independently predict both OS and LRFS.

CONCLUSIONS

LNR performs better than other LN related parameters for predicting survival. After radical resection followed by adjuvant treatment, survival of patients with one positive LN does not seem to differ from patients without LN metastasis.

Contemporary reappraisal of the efficacy of adjuvant chemotherapy in resected retroperitoneal sarcoma: Evidence from a nationwide clinical oncology database and review of the literature

BACKGROUND

While margin-negative resection remains the cornerstone of therapy for retroperitoneal sarcoma (RPS), the impact of adjuvant chemotherapy (AC) on overall survival (OS) remains poorly understood.

METHODS

The National Cancer Data Base was queried for patients undergoing curative-intent resection of primary non-metastatic RPS (2004-2013). Multivariable modeling identified factors associated with AC receipt. Cox regression identified covariates associated with OS, and AC and surgery alone (SA) cohorts were matched 1:1 by propensity scores based on these covariates. In the propensity-score matched cohort, OS was compared by Kaplan-Meier estimates. Results from this analysis were presented in the context of a review of the existing literature on the impact of AC in resected RPS.

RESULTS

Of 3892 resected RPS patients, 90.0% and 10.0% received SA and AC, respectively. Predictors of AC receipt included younger age, non-Caucasian race, hospital location, histologic grade, adjacent organ invasion, and histologic subtype. The propensity score-matched cohort comprised 767 patients (SA n = 377; AC n = 390); at a median follow-up of 59.2 (IQR 35.0-85.3) months, median OS of the propensity-matched cohort was 53.6 (IQR 22.4-119.5) months. Utilization of AC was associated with significantly worse long-term survival (median OS: 47.8 vs. 68.9 months, p = 0.017; HR 1.30, 95% CI 1.05-1.61). AC was not associated with improved OS in margin-positive (R1/R2) resection, high-grade (G2/G3) and larger (>10 cm) tumors, or in any histologic subtype. Albeit not statistically significant, there was a trend toward improved OS with AC in spindle cell (HR 0.37, 95% CI 0.10-1.38), giant cell (HR 0.82, 95% CI 0.32-2.13), and synovial (HR 0.26, 95% CI 0.05-1.33) sarcoma.

CONCLUSIONS

Data from a large nationwide oncology database and review of the existing literature do not support adjuvant chemotherapy regimens following curative-intent resection of RPS, even in subgroups at high risk of failure (e.g., R1/R2 resection, high-grade or large tumors). The possible benefit of conventional adjuvant regimens in spindle cell, giant cell, and synovial sarcoma should be explored in prospective studies.

Comparison of different lymph node staging systems in prognosis of gastric cancer: a bi-institutional study from Hungary

Objective

The Union for International Cancer Control (UICC) Node (N) classification is the most common used staging method for the prognosis of gastric cancer. It demands adequate, at least 16 lymph nodes (LNs) to be dissected; therefore different staging systems were invented.

Methods

Between March 2005 and March 2010, 164 patients were evaluated at the Department of General Surgery in the Kenézy Gyula Hospital and at the Department of General, Thoracic and Vascular Surgery in the Kaposi Mór Hospital. The 6th, 7th and 8th UICC N-staging systems, the number of examined LNs, the number of harvested negative LNs, the metastatic lymph node ratio (MLR) and the log odds of positive LNs (LODDS) were determined to measure their 5-year survival rates and to compare them to each other.

Results

The overall 5-year survival rate for all patients was 55.5% with a median overall survival time of 102 months. The tumor stage, gender, UICC N-stages, MLR and the LODDS were significant prognostic factors for the 5-year survival with univariate analysis. The 6th UICC N-stage did not follow the adequate risk in comparing N2 vs. N0 and N3 vs. N0 with multivariate investigation. Comparison of performances of the residual N classifications proved that the LODDS system was first in the prediction of prognosis during the evaluation of all patients and in cases with less than 16 harvested LNs. The MLR gave the best prognostic prediction when adequate (more than or equal to 16) lymphadenectomy was performed.

Conclusions

We suggest the application of LODDS system routinely in western patients and the usage of MLR classification in cases with extended lymphadenectomy.

Influence of Total Lymph Node Count on Staging and Survival After Gastrectomy for Gastric Cancer: An Analysis From a Two-Institution Database in China

BACKGROUND

Although current guidelines suggest that 16 or more lymph nodes (LNs) are required for the appropriate staging of gastric cancer, the effect that the minimum number of examined LNs (eLNs) in the different types of gastrectomy has on survival remains unclear.

METHODS

This study retrospectively analyzed 2662 patients who underwent curative gastrectomy with D2 lymphadenectomy for gastric cancer at Fujian Medical University Union Hospital from January 2000 to December 2010 and randomly divided them into development (70 %, n = 1863) and validation (30 %, n = 799) data sets. An additional external validation was performed using the data set (n = 285) collected during the same period from the Sun Yat-sen University Cancer Center in Guangzhou, China. A hypothetical tumor-node-metastasis (TNM) classification (hTNM) was proposed based on eLNs and survival.

RESULTS

The mean numbers of nodes removed during radical distal and total gastrectomy were respectively 26 ± 9.6 and 29 ± 10.7 (p < 0.01). The optimal LN-count thresholds were determined to be 16 for patients who underwent curative distal gastrectomy and 21 for patients who underwent total gastrectomy. The hTNM staging system had higher linear trend and likelihood ratio χ ² scores and lower Akaike information criterion (AIC) values than the seventh American Joint Committee on Cancer (AJCC) TNM classification. Thus, the hTNM staging system exhibited superior prognostic stratification. Similar results were found in the two validation data sets.

CONCLUSION

A harvest of at least 21 LNs may represent a superior threshold for radical total gastrectomy (RTG) and could yield a better prognosis. For patients undergoing RTG, the hTNM staging system may predict survival more accurately and discriminatively. However, a validation from a Western institution is warranted.

Multimodality Therapy Improves Survival in Resected Early Stage Gastric Cancer in the United States

BACKGROUND

National guidelines endorse adjuvant chemotherapy ± radiotherapy (C ± RT) for early-stage gastric cancer (ESGC). Compliance with these guidelines and the specific impact of adjuvant C ± RT on overall survival (OS) in ESGC have not been extensively explored.

METHODS

The National Cancer Data Base was queried for stage IB-II gastric adenocarcinoma patients undergoing gastrectomy (1998-2011). Multivariable modeling identified factors associated with adjuvant C ± RT receipt and compared risk-adjusted OS by treatment type (i.e., adjuvant therapy versus surgery alone).

RESULTS

Of 23,461 ESGC patients (1998-2011), 79.4 % and 20.6 % received surgery alone and adjuvant C ± RT (chemoradiotherapy 17.7 %; chemotherapy alone 2.9 %), respectively. Predictors of adjuvant C ± RT receipt included age <67 years, pathologic nodal positivity, and adequate lymph node staging (LNS; ≥15 nodes examined; all p < 0.001). Survival analyses included 15,748 patients (1998-2006); median, 1-, and 5-year survival were 63.5 months, 86.0 %, and 27.0 % respectively. Omission of adjuvant C ± RT conferred an increased hazard of risk-adjusted mortality in the overall cohort, and stage IB and II subgroups (all p ≤ 0.001). The benefit of adjuvant C ± RT was most pronounced in stage II and node-positive patients-regardless of LNS adequacy (all p < 0.001)-and inadequately staged IB patients (p = 0.003). While associated with a trend toward improved OS in node-negative patients overall (p = 0.051), adjuvant C ± RT did not improve OS if surgical LNS was adequate in this subgroup (p = 0.960).

CONCLUSIONS

Adoption of adjuvant C ± RT in ESGC remains incomplete nationally. Receipt of adjuvant therapy is associated with improved risk-adjusted survival relative to surgery alone; however, in adequately staged patients without lymph node metastasis, this benefit is less certain.

Clinical study of harvesting lymph nodes with carbon nanoparticles in advanced gastric cancer: a prospective randomized trial

Background

The objective of this study is to evaluate the efficiency and safety of carbon nanoparticles (CNPs) for harvesting lymph nodes (LNs) in cases of advanced gastric cancer (AGC).

Methods

Patients with previously untreated resectable AGC were eligible for inclusion in this study. All patients were randomly allocated to two subgroups. In the experimental group, 1.0 mL of CNP was injected into the subserosa of the stomach around the tumor before gastrectomy with D2 dissection. The same procedure was performed directly without any coloring material in the control arm. Following surgery, LNs were harvested, colored LNs were counted, and the diameters were measured by the investigator and pathologist.

Results

Thirty patients were enrolled in the study. We observed no serious adverse effects related to CNP injection. The rate of stained LNs was 46.6 %. The mean number of harvested LNs was larger in the experimental than in the control group (38.33 vs 28.27, p = 0.041). A smaller diameter of LNs was recorded in the experimental arm (3.32 vs 4.30 mm, p = 0.023). In addition, we developed a model for predicting the total number of LNs based on the data from CNP-stained LNs and metastatic LNs (MLNs).

Conclusions

CNP is a safe material. Surgeons could harvest more LNs in patients with AGC. The harvest of an increased number of smaller diameters of LNs may be beneficial. Further study is warranted to demonstrate the model’s practicality.

Clinical significance of lymphadenectomy in patients with gastric cancer

Approximately thirty percent of patients with gastric cancer undergo an avoidable lymph node dissection with a higher rate of postoperative complication. Comparing the D1 and D2 dissections, it was found that there is a significant difference in morbidity, favoured D1 dissection without any difference in overall survival. Subgroup analysis of patients with T3 tumor shows a survival difference favoring D2 lymphadenectomy, and there is a better gastric cancer-related death and non-statistically significant improvement of survival for node-positive disease in patients with D2 dissection. However, the extended lymphadenectomy could improve stage-specific survival owing to the stage migration phenomenon. The deployment of centralization and application of national guidelines could improve the surgical outcomes. The Japanese and European guidelines enclose the D2 lymphadenectomy as the gold standard in R0 resection. In the individualized, stage-adapted gastric cancer surgery the Maruyama computer program (MCP) can estimate lymph node involvement preoperatively with high accuracy and in addition the Maruyama Index less than 5 has a better impact on survival, than D-level guided surgery. For these reasons, the preoperative application of MCP is recommended routinely, with an aim to perform “low Maruyama Index surgery”. The sentinel lymph node biopsy (SNB) may decrease the number of redundant lymphadenectomy intraoperatively with a high detection rate (93.7%) and an accuracy of 92%. More accurate stage-adapted surgery could be performed using the MCP and SNB in parallel fashion in gastric cancer.

Efficacy of adjuvant chemotherapy for small bowel adenocarcinoma: A propensity score-matched analysis

BACKGROUND

The role of adjuvant chemotherapy (AC) in the treatment of small bowel adenocarcinoma is poorly defined. Previous analyses have been limited by small sample sizes and have failed to demonstrate a survival advantage.

METHODS

Patients with resected small bowel adenocarcinoma (American Joint Committee on Cancer [AJCC] pathologic stage I-III) who were receiving AC (n = 1674) or surgery alone (SA; n = 3072) were identified in the NCDB (1998-2011). Cox regression identified covariates associated with overall survival (OS). AC and SA cohorts were matched (1:1) by propensity scores based on the likelihood of receiving AC or the survival hazard from Cox modeling. OS was compared with Kaplan-Meier estimates.

RESULTS

The omission of AC conferred an increased risk of death (hazard ratio, 1.36; 95% confidence interval, 1.24-1.50; P < .001). After propensity score matching, there was a nonsignificant trend toward improved OS with AC in AJCC stage I patients (158.8 vs 110.7 months; P = .226) and AJCC stage II patients (104.0 vs 79.6 months; P = .185), including the subset with a T4 tumor classification (64.0 vs 47.4 months; P = .130) or a positive resection margin (44.4 vs 31.0 months; P = .333). Median OS was superior for patients with AJCC stage III disease who were receiving AC versus SA (42.4 vs 26.1 months; P < .001).

CONCLUSIONS

These data support the use of AC for resected stage III small bowel adenocarcinoma. The trend toward improved OS for patients without nodal metastasis, including those who have T4 tumors or have undergone positive-margin resection, may justify the use of AC in select patients with earlier stage disease. Cancer 2016;122:693-701. © 2015 American Cancer Society.

Neoadjuvant therapy for gastric cancer: current evidence and future directions

Although surgical resection remains the only potentially curative treatment for gastric cancer (GC), poor long-term outcomes with resection alone compel a multimodality approach to this disease. Multimodality strategies vary widely; while adjuvant approaches are typically favored in Asia and the United States (USA), a growing body of evidence supports neoadjuvant and/or perioperative strategies in locally advanced tumors. Neoadjuvant approaches are particularly attractive given the morbidity associated with surgical management of GC and the substantial risk of omission of adjuvant therapy. The specific advantages of chemoradiotherapy (CRT) compared to chemotherapy have not been well defined, particularly in the preoperative setting and trials aimed at determining the optimal elements and sequencing of therapy are underway. Future studies will also define the role of targeted and biologic therapies.

Minimally invasive gastrectomy for gastric adenocarcinoma in the United States: Utilization and short-term oncologic outcomes

BACKGROUND AND OBJECTIVES

When performed at select centers, minimally invasive gastrectomy (MIG) for gastric adenocarcinoma is associated with reduced perioperative morbidity, and similar oncologic outcomes as compared to open gastrectomy (OG). Utilization of, and outcomes associated with, MIG in the United States have not been characterized.

METHODS

The National Cancer Database (2010-2011) was queried for AJCC pStage IB-IIIC patients who underwent curative-intent OG (n = 2,303) or MIG (n = 331). Multivariable models identified factors associated with MIG utilization, R0 resection rates, and adequate lymph node staging (LNS).

RESULTS

MIG was more frequently utilized for T1/T2 (P < 0.001), N0 (P = 0.022), and stage IB (P = 0.001) tumors. MIG was associated with shorter hospital stay (P < 0.001), equivalent lymph node examination (P = 0.337) and superior rates of R0 resection (P = 0.011) compared with OG. In patients undergoing MIG, R0 resection was associated with performance of near-total/total gastrectomy (OR 3.90, 95%CI 1.10-13.9) and tumors < 5 cm (OR 2.78, 95%CI 1.07-7.26). Adequate LNS was associated with surgery at academic (OR 1.99, 95%CI 1.19-3.32) or high-volume facilities (OR 2.97, 95%CI 1.59-5.54), tumor size ≥ 5 cm (OR 1.85, 95%CI 1.10-3.11), and node positivity (OR 1.75, 95%CI 1.04-2.93).

CONCLUSIONS

MIG is selectively utilized in cases with favorable tumor characteristics. In such cases, short-term oncologic outcomes are equivalent to those achieved with OG. Worse oncologic outcomes in specific subgroups underscore opportunities for quality improvement.