Impact of Minimally Invasive Approach on Attainment of a Textbook Oncologic Outcome Following Gastrectomy for Gastric Cancer: A Review of the National Cancer Database

BACKGROUND

Textbook oncologic outcome (TOO) is a composite outcome measure realized when all desired short-term quality metrics are met following an oncologic operation. This study examined whether minimally invasive gastrectomy (MIG) is associated with increased likelihood of TOO attainment.

METHODS

The 2010-2016 National Cancer Database was queried for patients with gastric cancer who underwent gastrectomy. Surgical approach was described as open (OG), laparoscopic (LG), or robotic (RG). TOO was defined as having met five metrics: R0 resection, AJCC compliant lymph node evaluation (n ≥ 15), no prolonged length of stay (< 75th percentile by year), no 30-day readmission, and receipt of guideline-accordant systemic therapy.

RESULTS

Of 21,015 patients identified, 5708 (27.2%) underwent MIG (LG = 21.9%, RG = 5.3%). Patients who underwent RG were more likely to have met all TOO criteria, and consequently TOO. Logistic regression models revealed that patients undergoing MIG were significantly more likely to attain TOO. MIG was associated with a higher likelihood of adequate LAD, no prolonged LOS, and concordant chemotherapy. Patients who underwent LG and achieved TOO had the highest median OS (86.7 months), while the OG non-TOO cohort experienced the lowest (34.6 months). The median OS for the RG TOO group was not estimable; however, the mortality rate (.7%) was the lowest of the six cohorts.

CONCLUSION

RG resulted in a significantly increased likelihood of TOO attainment. Although TOO is associated with increased OS across all surgical approaches, attainment of TOO following MIG is associated with a statistically significantly higher median OS.

Impact of Textbook Oncologic Outcome Attainment on Survival After Gastrectomy: A Review of the National Cancer Database

BACKGROUND

Textbook oncologic outcome (TOO) is a composite outcome measure realized when all desired short-term quality metrics are met after an oncologic operation. This study examined the incidence and impact of achieving a TOO among patients undergoing resection of gastric adenocarcinoma.

METHODS

The 2004-2016 National Cancer Database was queried for patients who underwent curative gastrectomy. Textbook oncologic outcome was defined as having met five metrics: R0 resection, American Joint Committee on Cancer-compliant lymph node evaluation (n ≥ 15), no prolonged hospital stay (< 75th percentile by year), no 30-day readmission, and receipt of guideline-accordant systemic therapy.

RESULTS

Of 34,688 patients identified, 8249 (23.8 %) achieved TOO. The patients for whom TOO was achieved were more likely to have traveled farther (p < 0.001) and received care in an academic (p < 0.001) or very high case-volume facility (p < 0.001). The TOO group had a significanty higher median overall survival (OS) than the non-TOO group (80.5 vs 35.3 months; p < 0.001). The Kaplan-Meier curve showed that at 12 months, the survival probability estimate was 92 % for the TOO group versus 77 % for the non-TOO group. At 60 months (long-term survival), survival probability estimates remained higher for the TOO group (57 % vs 38 %). The results of the multivariate Cox regression model found that TOO attainment was significantly associated with a reduced risk of death (hazard ratio, 0.82; p < 0.001).

CONCLUSION

The TOO measure is associated with improved OS and reduced risk of death after gastrectomy for gastric adenocarcinoma. Unfortunately, in this study, TOO was obtained in only 23.8 % of cases.

Assessment of Carbon Nanoparticle Suspension Lymphography-Guided Distal Gastrectomy for Gastric Cancer

IMPORTANCE

Carbon nanoparticle suspension injection (CNSI) can be used to visualize lymph node (LN) drainage in gastric cancer. The tracing and diagnostic value of carbon nanoparticle suspension lymphography-guided distal gastrectomy for gastric cancer has not been thoroughly reported.

OBJECTIVE

To compare the number of lymph nodes identified in patients with gastric cancer receiving a CNSI vs no injection.

DESIGN, SETTING, AND PARTICIPANTS

This is a retrospective cohort study including patients with clinical T1 to T4 disease who underwent laparoscopic or robotic distal gastrectomy. Data from a cohort of 1225 patients at the Fourth Hospital of Hebei Medical University (Shijiazhuang, China) from November 2019 to February 2021 were analyzed. Patients were divided into the CNSI group and conventional group after 1:1 propensity matching analysis. The mean number of LNs detected was compared between groups, and the diagnostic role of CNSI was analyzed in the CNSI group. Statistical analysis was performed from May to July 2021.

EXPOSURE

CNSI was peritumorally injected under an endoscope 1 day before surgery in the CNSI group, and the conventional group did not receive any treatment before surgery.

MAIN OUTCOMES AND MEASURES

The main outcome was the number of LNs detected. Gastrectomy with systematic D1+ (ie, stations 1, 3, 4sb, 4d, 5, 6, and 7) or D2 (ie, all D1 stations, plus 8a, 9, 11p, and 12a) lymphadenectomy was performed. Black-stained LNs and nonblack-stained LNs were examined separately in the CNSI group.

RESULTS

A total of 312 consecutive patients (mean [SD] age, 56.7 [10.4] years; 216 [69.2%] men) who underwent distal gastrectomy were enrolled, including 78 patients in the CNSI group, and another 78 patients determined from 1:1 propensity score matching, making an overall cohort size of 156 patients. The mean (SD) number of LNs detected in the CNSI group was 59.6 (21.4), which was significantly higher than that in the conventional group (30.0 [11.3] LNs; P < .001). In the CNSI group, the mean (SD) number of LNs detected at black-stained LN stations was significantly higher than that at nonstained LN stations (9.2 [6.1] LNs per station vs 3.5 [3.2] LNs per station; P < .001). For black-stained LN stations, the sensitivity was 97.8% (95% CI, 91.6%-99.6%), specificity was 38.1% (95% CI, 34.2%-42.3%), positive predictive value was 20.1% (95% CI, 16.6%-24.2%), and negative predictive value was 99.1% (95% CI, 96.4%-99.8%); for the black-stained LNs, sensitivity was 97.6% (95% CI, 95.3%-98.8%), specificity was 35.4% (95% CI, 33.9%-36.8%), positive predictive value was 11.6% (95% CI, 10.5%-12.8%), and negative predictive value was 99.4% (95% CI, 98.8%-99.7%).

CONCLUSIONS AND RELEVANCE

These findings suggest that CNSI was associated with facilitating the dissection of all positive LNs, which could improve surgical quality. Carbon nanoparticle suspension-guided lymphography may be an alternative to conventional systematic lymphadenectomy for distal gastrectomy.

Impact of the Deep Neuromuscular Block on Oncologic Quality of Laparoscopic Surgery in Obese Gastric Cancer Patients: A Randomized Clinical Trial

BACKGROUND

Obesity can hinder laparoscopic procedures and impede oncological safety during laparoscopic cancer surgery. Deep neuromuscular block (NMB) reportedly improves laparoscopic surgical conditions, but its oncological benefits are unclear. We aimed to evaluate whether deep NMB improves the oncologic quality of laparoscopic cancer surgery in obese patients.

STUDY DESIGN

We conducted a double-blinded, parallel-group, randomized, phase 3 trial at 9 institutions in Korea. Clinical stage I and II gastric cancer patients with a BMI at or above 25 kg m -2 were eligible and randomized 1:1 ratio to the deep or moderate NMB groups, with continuous infusion of rocuronium (0.5-1.0 and 0.1-0.5 mg kg -1 h -1, respectively). The primary endpoint was the number of retrieved lymph nodes (LNs). The secondary endpoints included the surgeon's surgical rating score (SRS) and interrupted events.

RESULTS

Between August 2017 and July 2020, 196 patients were enrolled. Fifteen patients were excluded, and 181 patients were finally included in the study. There was no significant difference in the number of retrieved LNs between the deep (N = 88) and moderate NMB groups (N = 93; 44.6 ± 17.5 vs 41.5 ± 16.9, p = 0.239). However, deep NMB enabled retrieving more LNs in patients with a BMI at or above 28 kg/m2 than moderate NMB (49.2 ± 18.6 vs 39.2 ± 13.3, p = 0.026). Interrupted events during surgery were lower in the deep NMB group than in the moderate NMB group (21.6% vs 36.6%; p = 0.034). The SRS was not influenced by NMB depth.

CONCLUSION

Deep NMB provides potential oncologic benefits by retrieving more LNs in patients with BMI at or above 28 kg/m2 during laparoscopic gastrectomy.

RECURRENCE IN PN0 GASTRIC CANCER: RISK FACTORS IN THE OCCIDENT

BACKGROUND

Nearly 10% of node negative gastric cancer patients who underwent curative surgery have disease recurrence. Western data is extremely poor on this matter and identifying the risk factors that associate with relapse may allow new strategies to improve survival.

AIM

Verify the clinical and pathological characteristics that correlate with recurrence in node negative gastric cancer.

METHODS

All gastric cancer patients submitted to gastrectomy between 2009 and 2019 at our institution and pathologically classified as N0 were considered. Their data were available in a prospective database. Inclusion criteria were: gastric adenocarcinoma, node negative, gastrectomy with curative intent, R0 resection. Main outcomes studied were: disease-free survival and overall survival.

RESULTS

A total of 270 patients fulfilled the inclusion criteria. Mean age was 63-year-old and 155 were males. Subtotal gastrectomy and D2 lymphadenectomy were performed in 64% and 74.4%, respectively. Mean lymph node yield was 37.6. Early GC was present in 54.1% of the cases. Mean follow-up was 40.8 months and 19 (7%) patients relapsed. Disease-free survival and overall survival were 90.9% and 74.6%, respectively. Independent risk factors for worse disease-free survival were: total gastrectomy, lesion size ≥3.4 cm, higher pT status and <16 lymph nodes resected.

CONCLUSION

In western gastric cancer pN0 patients submitted to gastrectomy, lymph node count <16, pT3-4 status, tumor size ≥3.4 cm, total gastrectomy and presence of lymphatic invasion, are all risk factors for disease relapse.

Safety and Efficacy of Indocyanine Green Tracer-Guided Lymph Node Dissection During Laparoscopic Radical Gastrectomy in Patients With Gastric Cancer: A Randomized Clinical Trial

Importance

The application of indocyanine green (ICG) imaging in laparoscopic radical gastrectomy is in the preliminary stages of clinical practice, and its safety and efficacy remain controversial.

Objective

To investigate the safety and efficacy of ICG near-infrared tracer-guided imaging during laparoscopic D2 lymphadenectomy in patients with gastric cancer.

Design, Setting, and Participants

Patients with potentially resectable gastric adenocarcinoma (clinical tumor stage cT1-cT4a, N0/+, M0) were enrolled in a prospective randomized clinical trial at a tertiary referral teaching hospital between November 2018 and July 2019. Patients were randomly assigned to the ICG group or the non-ICG group. The number of retrieved lymph nodes, rate of lymph node noncompliance, and postoperative recovery data were compared between the groups in a modified intention-to-treat analysis. Statistical analysis was performed from August to September 2019.

Interventions

The ICG group underwent laparoscopic gastrectomy using near-infrared imaging after receiving an endoscopic peritumoral injection of ICG to the submucosa 1 day before surgery.

Main Outcomes and Measures

Total number of retrieved lymph nodes.

Results

Of 266 participants randomized, 133 underwent ICG tracer-guided laparoscopic gastrectomy, and 133 underwent conventional laparoscopic gastrectomy. After postsurgical exclusions, 258 patients were included in the modified intention-to-treat analysis, which comprised 129 patients (86 men and 43 women; mean [SD] age, 57.8 [10.7] years) in the ICG group and 129 patients (87 men and 42 women; mean [SD] age, 60.1 [9.1] years) in the non-ICG group. The mean number of lymph nodes retrieved in the ICG group was significantly more than the mean number retrieved in the non-ICG group (mean [SD], 50.5 [15.9] lymph nodes vs 42.0 [10.3] lymph nodes, respectively; P < .001). Significantly more perigastric and extraperigastric lymph nodes were retrieved in the ICG group than in the non-ICG group. In addition, the mean total number of lymph nodes retrieved in the ICG group within the scope of D2 lymphadenectomy was also significantly greater than the mean number retrieved in the non-ICG group (mean [SD], 49.6 [15.0] lymph nodes vs 41.7 [10.2] lymph nodes, respectively; P < .001). The lymph node noncompliance rate of the ICG group (41 of 129 patients [31.8%]) was lower than that of the non-ICG group (74 of 129 patients [57.4%]; P < .001). The postoperative recovery process was comparable, and no significant difference was found between the ICG and non-ICG groups in the incidence (20 of 129 patients [15.5%] vs 21 of 129 [16.3%], respectively; P = .86) or severity of complications within 30 days after surgery.

Conclusions and Relevance

Indocyanine green can noticeably improve the number of lymph node dissections and reduce lymph node noncompliance without increased complications in patients undergoing D2 lymphadenectomy. Indocyanine green fluorescence imaging can be performed for routine lymphatic mapping during laparoscopic gastrectomy, especially total gastrectomy.

Trial Registration

ClinicalTrials.gov Identifier: NCT03050879.

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

Background

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

Methods

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

Results

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

Conclusions

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

Nodes staging score to quantify lymph nodes for examination in gastric cancer

The lymph nodal invasion diagnosis is critical for therapeutic-decision and follows up in gastric cancer. However, the number of nodes to be examined for nodal invasion diagnosis is still under controversy, and the model for quantifying risk of missing positive node is currently not reported yet. We analyzed the nodal invasion status of 13,857 gastric cancer samples with records of primary tumor stage, the number of examined and positive lymph nodes in the surveillance, epidemiology, and end results (SEER) database, fitting a beta-binomial model. The nodes need to be examined with different primary tumor stage were determined based on the model. Overall, examining 11 lymph nodes reduces the probability of missing positive nodes to <10%, and the currently median nodes dissected is adequate (12 nodes). While the number of nodes demands to be dissected for T1, T2, T3, and T4 subgroups are 6, 19, 40, and 66, respectively. The currently implemented median value for these samples was 12, 12, 13, and 16, separately. It implies that the number of nodes to be examined is sufficient for early gastric cancer (T1), but it is inadequate for middle and advanced gastric cancer (T2-T3). The clinical significance of nodal staging score was validated with survival information. In summary, we first quantified the lymph nodes to be examined during surgery using a beta-binomial model, and validated with survival information.

Laparoscopic Versus Open D2 Gastrectomy for Gastric Cancer: A Case-Matched Comparative Study

Background: The role of the laparoscopic approach to D2 gastrectomy for gastric cancer remains controversial. The aim of this study was to compare the operative and short-term oncologic outcomes of laparoscopic versus open resections. Methods: Patients who underwent potentially curative D2 gastrectomy between 2017 and 2019 were retrospectively reviewed. Patients were randomly matched on 1:1 basis for age and extent of surgery (total versus subtotal gastrectomy, and additional organ resection). Exclusions included emergency or palliative surgery. The learning curve for laparoscopic resections was included. Analysis was conducted on intention to treat basis. The outcomes were reported as median (range) or per cent as appropriate. Results: Among 78 patients who had undergone potentially curative gastrectomy 36 were matched. The groups were comparable for age, sex, American Society of Anesthesiologists (ASA) score, preoperative serum albumin and hemoglobin, body mass index, frequency of previous abdominal surgery, anatomic distribution of disease, extent of gastrectomy, need for additional resection, and disease stage. There was one conversion to open surgery. Although laparoscopic surgery required longer operating time (393 versus 218 minutes, P < .001), it was associated with less blood loss (100 versus 200 mL, P = .001) and shorter hospital stay (3.0 versus 7.5 days, P < .001). There were no significant differences in the rates of clinically significant complications, mortality, readmissions, reoperations, lymph node retrieval, and R₁ resections. Conclusions: The laparoscopic approach to potentially curative D2 gastrectomy for gastric cancer is associated with less operative trauma and quicker recovery while offering an equivalent oncologic resection.

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.

Single Purse-String Suture for Reinforcement of Duodenal Stump During Laparoscopic Radical Gastrectomy for Gastric Cancer

Background: Duodenal stump leakage (DSL) is a serious surgical complication after radical gastrectomy with Roux-en-Y or BillrothII reconstruction. This study was designed to evaluate the effectiveness of laparoscopic single purse-string suture for reinforcement of duodenal stump.

Methods: A total of 183 patients harboring gastric adenocarcinoma following laparoscopic radical gastrectomy with Roux-en-Y or BillrothIIreconstruction and single purse-string suture for reinforcement of duodenal stump were retrospectively enrolled from Zhongshan Hospital of Fudan University (Shanghai, China) between January 2014 and December 2016. Operative variables and short-term complications were documented and analyzed. Clavien-Dindo classification system was used to identify surgical complications.

Results: Among 183 patients, 108 (59.02%) patients received distal gastrectomy and 75 (40.98%) received total gastrectomy. 88 (48.09%) patients underwent Roux-en-Y reconstruction and 95 (51.91%) patients underwent Billroth-II reconstruction. The mean time of laparoscopic single purse-string suture was 5.01 ± 1.33 min (range from 3.6 to 10.2 min). Postoperative early complication occurred in 26 cases of the patients. There were 4 cases of system-related complications (2.19%), including 3 cases of pulmonary infection (1.64%) and 1 cases of cardiovascular event (0.55%); and 22 cases of surgery-related complications (12.02%), including 6 cases of intra-abdominal infection (3.28%), 4 cases of pancreatic leakage (2.19%), 4 cases of wound complications (2.19%), 3 cases of gastroparesis (1.64%), 2 cases of intra-abdominal bleeding (1.09%), 2 cases of ileus (1.09%), 1 cases of lymphatic leakage (0.55%), and no duodenal stump leakage.

Conclusion: Reinforcement on duodenal stump using laparoscopic single purse-string suture during laparoscopic radical gastrectomy is simple and effective and could avoid the incidence of duodenal stump leakage to some extent.

Siewert III esophagogastric junction adenocarcinoma: does TNM 8th save us?

Siewert III cancers were classified as esophageal cancers by the TNM 7th edition (TNM7), while being defined as gastric cancers by the new TNM 8th edition (TNM8). Aim of this study was to compare previous and present TNM classifications of Siewert III. From 2000 to 2015, 309 patients with Siewert III adenocarcinoma were treated at ten high-volume centers, belonging to the GIRCG (Italian Research Group for Gastric Cancer). We retrospectively analyzed overall survival according to TNM classifications: gastric TNM8 was compared with either gastric TNM7 or esophageal TNM7. Median number of lymph nodes harvested was 31 (interquartile range 22-44). Agreement between gastric TNM7 and TNM8 was very good (weighted kappa 92.3%, IC 95% 90.3-94.1%). Accordingly, stage migration was observed in 54 of 309 patients (17.5%), with 12 patients upstaged (3.9%) and 42 downstaged (13.6%). Cox models including either gastric TNM7 or TNM8 achieved similar goodness-of-fit and c-index. Differences were much larger, when shifting from esophageal TNM7 to gastric TNM8: the agreement was much lower (weighted kappa 69.1%, 65.2-73.2%), with 196 of 309 patients (63.4%) downstaging. The corresponding Cox model presented the lowest goodness-of-fit and discrimination ability. Gastric TNM7 and TNM8 were largely superimposable, so that stage migration was minor and prognostic significance was similar. At variance, stage migration was substantial when shifting from esophageal TNM7 to TNM8. Moreover, survival models with esophageal TNM7 presented the worst goodness-of-fit and the lowest discrimination ability. This further supports placing Siewert III among gastric cancers, as done in TNM8.

Increased number of negative lymph nodes is associated with improved survival outcome in node positive gastric cancer following radical gastrectomy

The concept of negative lymph node (NLN) counts has recently attracted attention as a prognostic indicator in various cancer. However, the correlation between NLN counts and patient prognosis in the setting of gastric cancer is not fully studied. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Clinicopathological characteristics, including race, age, gender, and tumor stage, grade, and cause specific survival were collected. Univariate and multivariate Cox proportional hazards model were used to assess the risk factors for survival. As results, X-tile plots identified 3 and 9 as the optimal cutoff value to divide the patients into high, middle and low risk subsets in terms of cause specific survival, and NLN was validated as independently prognostic factor in mulivariate Cox analysis (P < 0.001). Further analysis showed that NLN was a prognosis factor in each N stage. Collectively, our study results firmly demonstrated that the number of NLNs was an independent prognostic factor for gastric cancer patients, and together with the N stage, it could provide more accurate prognostic information than the N stage alone.

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.

Greater Lymph Node Retrieval Improves Survival in Node-Negative Resected Gastric Cancer in the United States

PURPOSE

Guidelines in western countries recommend retrieving ≥15 lymph nodes (LNs) during gastric cancer resection. This study sought to determine whether the number of examined lymph nodes (eLNs), a proxy for lymphadenectomy, effects survival in node-negative disease.

MATERIALS AND METHODS

The US National Cancer Database (2003-2011) was reviewed for node-negative gastric adenocarcinoma. Treatment was categorized by neoadjuvant therapy (NAT) vs. initial resection, and further stratified by eLN. Kaplan-Meier and Weibull models were used to analyze overall survival.

RESULTS

Of the 1,036 patients who received NAT, 40.5% had ≤10 eLN, and most underwent proximal gastrectomy (67.8%). In multivariate analysis, greater eLN was associated with improved survival (eLN 16-20: HR, 0.71; P=0.039, eLN 21-30: HR, 0.55; P=0.001). Of the 2,795 patients who underwent initial surgery, 42.5% had ≤10 eLN, and the majority underwent proximal gastrectomy (57.2%). In multivariate analysis, greater eLN was associated with improved survival (eLN 11-15: HR, 0.81; P=0.021, eLN 16-20: HR, 0.73; P=0.004, eLN 21-30: HR, 0.62; P<0.001, and eLN >30: HR, 0.58; P<0.001).

CONCLUSIONS

In the United States, the majority of node-negative gastrectomies include suboptimal eLN. In node-negative gastric cancer, greater LN retrieval appears to have therapeutic and prognostic value, irrespective of initial treatment, suggesting a survival benefit to meticulous lymphadenectomy.

Staging and surgical approaches in gastric cancer: a clinical practice guideline

BACKGROUND

Resection is the cornerstone of cure for gastric adenocarcinoma; however, several aspects of surgical intervention remain controversial or are suboptimally applied at a population level, including staging, extent of lymphadenectomy (lnd), minimum number of lymph nodes that have to be assessed, gross resection margins, use of minimally invasive surgery, and relationship of surgical volumes with patient outcomes and resection in stage iv gastric cancer.

METHODS

Literature searches were conducted in databases including medline (up to 10 June 2016), embase (up to week 24 of 2016), the Cochrane Library and various other practice guideline sites and guideline developer Web sites. A practice guideline was developed.

RESULTS

One guideline, seven systematic reviews, and forty-eight primary studies were included in the evidence base for this guidance document. Seven recommendations are presented.

CONCLUSIONS

All patients should be discussed at a multidisciplinary team meeting, and computed tomography (ct) imaging of chest and abdomen should always be performed when staging patients. Diagnostic laparoscopy is useful in the determination of M1 disease not visible on ct images. A D2 lnd is preferred for curative-intent resection of gastric cancer. At least 16 lymph nodes should be assessed for adequate staging of curative-resected gastric cancer. Gastric cancer surgery should aim to achieve an R0 resection margin. In the metastatic setting, surgery should be considered only for palliation of symptoms. Patients should be referred to higher-volume centres and those that have adequate support to manage potential complications. Laparoscopic resections should be performed to the same standards as those for open resections, by surgeons who are experienced in both advanced laparoscopic surgery and gastric cancer management.

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.

Negative lymph node count is a significant prognostic factor in patient with stage IV gastric cancer after palliative gastrectomy

Negative lymph node (NLN) count has been validated as a protective predictor in various cancers after radical resection. However, the prognostic value of NLN count in the setting of stage IV gastric cancer patients who have received palliative resection has not been investigated. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Kaplan-Meier survival curves and multivariate Cox proportional hazards model were used to assess the risk factors for patients’ survivals. The results showed that NLN count and N stage were independently prognostic factors in patients with stage IV gastric cancer after palliative surgery (P< 0.001). X-tile plots identified 2 and 11 as the optimal cutoff values to divide the patients into high, middle and low risk subsets in term of cause-specific survival (CSS). And NLN count was proved to be an independently prognostic factor in multivariate Cox analysis (P< 0.001). The risk score of NLN counts demonstrated that the plot of hazard ratios (HRs) for NLN counts sharply increased when the number of NLN counts decreased. Collectively, our present study revealed that NLN count was an independent prognostic predictor in stage IV gastric cancer after palliative resection. Standard lymph node dissection, such as D2 lymphadectomy maybe still necessary during palliative resection for patients with metastatic gastric cancer.

Prognostic impact of nodal status and therapeutic implications

The prognostic impact of lymph node (LN) metastases in gastric cancer is generally accepted. In primarily resected patients the pN-category and LN ratio are independent prognostic factors. Number of involved LNs, number of resected LNs, lymphangiosis and micrometastases also influence the prognosis significantly. To guarantee a proper D2 lymphadenectomy (LAD) at least 25 LNs according to the German S3 guidelines for the treatment of gastric cancer should be removed. Also in neoadjuvantly treated patients the ypN-category and LN ratio play an important prognostic role, despite the fact that UICC staging system was development based only on primarily resected patients. The role of response of LNs in neoadjuvantly treated patients is still unclear and needs further investigation. It seems to be less important than the response of the primary tumor. Limited data exists, suggesting that preoperative treatment might reduce the number of LNs involved and improve ypN-category. Due to further development in gastric cancer like laparoscopic resection and effective perioperative treatment in locally advanced tumor the role and the prognostic impact of LAD is again in the focus of discussion.

Increasing the Number of Examined Lymph Nodes is a Prerequisite for Improvement in the Accurate Evaluation of Overall Survival of Node-Negative Gastric Cancer Patients

BACKGROUND

This study aims to elucidate whether increasing the number of examined lymph nodes (NELN) is mandatory for the accurate prognosis of node-negative gastric cancer (GC) patients after curative gastrectomy in Eastern countries (China and Japan).

METHODS

The clinicopathological data of 2455 GC patients (including 1137 node-negative cases) were included to demonstrate whether a minimum NELN is inevitable for guaranteeing the accurate prognosis of node-negative GC patients after curative gastrectomy.

RESULTS

Survival analyses revealed that the NELN significantly positively correlated with overall survival (p < 0.001) and was an independent prognostic predictor (hazard ratio 0.447; p = 0.025) of 1137 node-negative GC patients. Stratum analysis within the Kaplan-Meier method showed that sex, tumor size, and extent of lymphadenectomy did not affect the NELN in predicting the prognosis of all node-negative GC patients. Stage migration was mainly detected in the subgroup of node-negative GC Chinese patients who presented considerably lower mean NELN and more advanced staging than patients from Japan. The NELN was identified as the most intensively independent predictor of prognosis of 600 node-negative GC patients from China, with the smallest Akaike information criterion (176.964) and Bayesian information criterion values (194.552). These findings indicate that increasing the NELN is a prerequisite to guaranteeing precise TNM classification.

CONCLUSIONS

The NELN should be considered a mandatory requirement for improving the accuracy of prognostic evaluation of GC patients, especially for advanced-stage patients.

Prognostic Factors for Node-Negative Advanced Gastric Cancer after Curative Gastrectomy

PURPOSE

Lymph node (LN) metastasis is the best prognostic indicator in non-distant metastatic advanced gastric cancer. This study aimed to assess the prognostic value of various clinicopathologic factors in node-negative advanced gastric cancer.

MATERIALS AND METHODS

We retrospectively analyzed the clinical records of 254 patients with primary node-negative stage T2~4 gastric cancer. These patients were selected from a pool of 1,890 patients who underwent radical resection at Memorial Jin-Pok Kim Korea Gastric Cancer Center, Inje University Seoul Paik Hospital between 1998 and 2008.

RESULTS

Of the 254 patients, 128 patients (50.4%), 88 patients (34.6%), 37 patients (14.6%), and 1 patient (0.4%) had T2, T3, T4a, and T4b tumors, respectively. In a univariate analysis, operation type, T-stage, venous invasion, tumor size, and less than 15 LNs significantly correlated with tumor recurrence and cumulative overall survival. In a multivariate logistic regression analysis, tumor size, venous invasion, and less than 15 LNs significantly and independently correlated with recurrence. In a multivariate Cox proportional hazards analysis, tumor size (hazard ratio [HR]: 2.926; 95% confidence interval [CI]: 1.173~7.300; P=0.021), venous invasion (HR: 3.985; 95% CI: 1.401~11.338; P=0.010), and less than 15 LNs (HR: 0.092; 95% CI: 0.029~0.290; P<0.001) significantly correlated with overall survival.

CONCLUSIONS

Node-negative gastric cancers recurred in 8.3% of the patients in our study. Tumor size, venous invasion, and less than 15 LNs reliably predicted recurrence as well as survival. Aggressive postoperative treatments and timely follow-ups should be considered in cases with these characteristics.