Lymph Node Noncompliance Affects the Long-Term Prognosis of Patients with Gastric Cancer after Laparoscopic Total Gastrectomy

Laparoscopic D2+ lymph node dissection in patients with obesity and gastric cancer: A retrospective study

D2 lymph node dissection is widely used in laparoscopic radical gastrectomy for gastric cancer, and its efficacy and safety are known for patients with obesity. Currently, D2+ lymph node dissection is also applied to certain patients with gastric cancer of later stages. Due to the high difficulty of D2+ surgery, it is more challenging to perform on patients with obesity. There is currently limited research on the efficacy and safety of D2+ surgery in obese patients with gastric cancer. The present study aimed to retrospectively analyze the clinical data of patients undergoing laparoscopic radical gastrectomy for gastric cancer admitted to a single gastroenterology department. Patients with a body mass index ≥25 kg/m2 were included in the study. A total of 149 patients were selected as the research subjects and divided into two groups. The observation group comprised 74 patients who underwent D2+ lymph node dissection, while the control group comprised 75 patients who underwent standard D2 lymph node dissection. The surgical performance, postoperative recovery and postoperative complications of the two groups were compared. The results showed that the rates of conversion to open surgery in the D2+ and D2 groups were 5.4% (4/74) and 2.7% (2/75), respectively, and were not significantly different. The duration of surgery in the D2+ group (282.55±23.02 min) was significantly longer than that in the D2 group (271.45±20.05 min). The mean number of lymph node dissections in the D2+ group was 28.57±7.19, which was significantly higher than that in the D2 group (25.29±6.41). No statistically significant differences in intraoperative blood loss, time to first flatus, postoperative hospitalization days, total hospitalization expenses or postoperative complications was detected between the two groups. There were no deaths in either group within the 30-day perioperative period. In addition, there was no significant difference in the 3-year overall survival rate between the two groups, while the 5-year overall survival rate of the D2+ group was significantly higher than that of the D2 group. For obese patients with gastric cancer, D2+ surgery may increase the duration of surgery and slightly increase intraoperative blood loss compared with standard D2 radical surgery, but does not increase the incidence of postoperative complications. Moreover, D2+ surgery increases the number of lymph node dissections and improves the 5-year survival rate of patients. Therefore, it may be concluded that laparoscopic D2+ lymph node dissection is safe and feasible for obese patients with gastric cancer.

OSATS scoring confirms ICG enhancement of performance in laparoscopic radical gastrectomy: a post-hoc analysis of a randomized controlled trial

BACKGROUND

Indocyanine green (ICG) fluorescence imaging is effective in increasing the number of lymph node dissections during laparoscopic radical gastrectomy; however, no studies have attempted to explain this phenomenon.

METHODS

This study utilized the data from a previous randomized controlled trial (FUGES-012 study) investigating ICG-guided laparoscopic radical gastrectomy performed between November 2018 and July 2019. The Objective Structured Assessments of Technical Skills (OSATS) scoring system was used to grade videos from the ICG and non-ICG groups. Patients with an OSATS score greater than 29 were classified as the high-OSATS population, while those with an OSATS score less than or equal to 29 were classified as the low-OSATS population.

RESULTS

A total of 258 patients were included in the modified intention-to-treat analysis: 129 in the ICG group and 129 in the non-ICG group. The OSATS score of the ICG group was higher than that of the non-ICG group (29.6±2.6 vs. 26.6±3.6; P <0.001). The ICG group underwent a significantly higher mean total number of lymph node dissections than the non-ICG group (50.5±15.9 vs. 42.0±10.3; adjusted P <0.001). The group assigned to ICG use, better OSATS (high-OSATS) scores were observed, which correlated with greater D2 lymph node retrieval (54.1±15.0 vs. 47.2±8.7; adjusted P =0.039). Finally, the ICG group had a lower rate of lymph node noncompliance than that of the non-ICG group (31.8 vs. 57.4%; P <0.001).

CONCLUSIONS

By applying the ICG fluorescence navigation technique, better OSATS scores were observed, which correlated with greater lymph node retrieval and a lower lymph node noncompliance rate, as recommended for individualized laparoscopic radical gastrectomy.

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.

Is No. 12a Lymph Node Dissection Compliance Necessary in Patients Who Undergo D2 Gastrectomy for Gastric Adenocarcinomas? A Population-Based Retrospective Propensity Score Matching Study

LN dissection is essential for accurately staging and improving GC patient prognosis. However, the compliance rate for No. 12a LND in practice is low, and its necessity is controversial. Data from GC patients who underwent total gastrectomy (TG)/distal gastrectomy (DG) plus D2 lymphadenectomy between January 2000 and December 2017 at West China Hospital, Sichuan University were reviewed. No. 12a LND noncompliance's effect on the long-term prognosis of patients with GC after D2 gastrectomy was explored. Of the 2788 patients included, No. 12a LND noncompliance occurred in 1753 patients (62.9%). Among 1035 patients with assessable LNs from station 12a, 98 (9.5%) had positive LNs detected at station 12a. No. 12a LN metastasis patients (stage IV not included) had significantly better overall survival (OS) than TNM stage IV patients (p = 0.006). Patients with No. 12a LND compliance had a significantly higher OS than those without, both before (p < 0.001) and after (p < 0.001) PSM. Cox multivariate analysis confirmed that No. 12a LND noncompliance was an independent prognostic factor before (HR 1.323, 95% CI 1.171-1.496, p < 0.001) and after (HR 1.353, 95% CI 1.173-1.560, p < 0.001) PSM. In conclusion, noncompliance with No. 12a LND compromised the long-term survival of patients who underwent D2 gastrectomy for GC.

Reciprocity between lymphadenectomy quality and adjuvant chemotherapy compliance in gastric cancer: post hoc analysis of two randomized controlled trials

OBJECTIVE

To investigate the effect of intraoperative lymph node (LN) dissection and postoperative adjuvant chemotherapy on the overall survival (OS) of gastric cancer (GC) patients and their reciprocity.

METHODS

LN noncompliance was defined as the absence of more than one LN station, as described in the protocol for D2 lymphadenectomy in the Japanese Gastric Cancer Association. The definition of adjuvant chemotherapy (AC) noncompliance was that the chemotherapy planned dose does not meet the requirements.

RESULTS

Kaplan-Meier survival curves showed that the OS of patients with major LN noncompliance was significantly lower than that of patients with nonmajor LN noncompliance, and the OS of AC noncompliance patients was significantly lower than that of AC compliance patients. If there was nonmajor LN noncompliance during surgery, the OS of patients with AC compliance was significantly higher than that of patients with AC noncompliance (P = 0.035). In the case of major LN noncompliance during surgery, there was no statistically significant difference in OS between those with AC compliance and those with AC noncompliance (P = 0.682). Multivariate Cox regression analysis including AC noncompliance indicated that major LN noncompliance was an independent prognostic factor for poor OS (P = 0.012), while AC noncompliance was not an independent prognostic factor for OS (P = 0.609).

CONCLUSION

Adequate lymph node dissection and adjuvant chemotherapy are both key steps to improve the awful prognosis of GC patients. Adjuvant chemotherapy may fail to remedy the poor prognosis caused by major LN noncompliance.

[ICG lymph node mapping in cancer surgery of the upper gastrointestinal tract]

The importance of the assessment of the N‑status in gastric carcinoma, tumors of the gastroesophageal junction and esophageal cancer is undisputed; however, there is currently no internationally validated method for lymph node mapping in esophageal and gastric cancer. Near-infrared fluorescence imaging (NIR) is an innovative technique from the field of vibrational spectroscopy, which in combination with the fluorescent dye indocyanine green (ICG) enables intraoperative real-time visualization of anatomical structures. The ICG currently has four fields of application in oncological surgery: intraoperative real-time angiography for visualization of perfusion, lymphography for visualization of lymphatic vessels, visualization of solid tumors, and (sentinel) lymph node mapping. For imaging of the lymph drainage area and therefore the consecutive lymph nodes, peritumoral injection of ICG must be performed. Several studies have demonstrated the feasibility of peritumoral injection of ICG administered 15 min to 3 days preoperatively with subsequent intraoperative visualization of the lymph nodes. So far prospective randomized studies on the validation of the method are still lacking. In contrast, the use of ICG for lymph node mapping and visualization of sentinel lymph nodes in gastric cancer has been performed in large cohorts as well as in prospective randomized settings. Up to now, multicenter studies for ICG-guided lymph node mapping during oncological surgery of the upper gastrointestinal tract are lacking. Artificial intelligence methods can help to evaluate these techniques in an automated manner in the future as well as to support intraoperative decision making and therefore to improve the quality of oncological surgery.

Determination of the extent of dissection in early gastric cancer based on lymph node station power index

Background

The relative prognostic value of each lymph node (LN) station remains undefined in the treatment of gastric cancer. This study aimed to develop a new method to evaluate LN station ranking and define the optimal extent of lymphadenectomy for early gastric cancer.

Methods

Clinical and histopathological information from patients who underwent curative gastrectomy with lymphadenectomy between 1989 and 2018 was reviewed. The LN station power index (LNPI) of each station was estimated using a LN retrieval frequency and the 5-year overall survival of patients with absence of LN at each station. External validation was conducted to evaluate the relevance of the LNPI.

Results

A training set was developed from examination of 7009 patient records. For most nodal stations, the absence of LN was significantly associated with a poor prognosis. For the perigastric stations, the prognostic value assessed using the LNPI was in the following order: LN 4 (LNPI = 19.68), LN 3 (LNPI = 17.58), LN 6 (LNPI = 15.16), LN 1 (LNPI = 6.71), LN 2 (LNPI = 4.64) and LN 5 (LNPI = 2.86). The value rank of the extra-gastric stations was in the following order: LN 8a (LNPI = 12.93), LN 7 (LNPI = 10.51) and LN 9 (LNPI = 9.70), but the index of LN 12a (LNPI = 4.79) was higher than that of LN 11 (LNPI = 4.78). These trends in the LNPI were similar in the validation patient cohort.

Conclusions

The LNPI is a simple tool to rank the priority of each LN station dissection. The optimal extent of D1 + lymphadenectomy using LNPI was determined to be D1 with LNs 7, 8a and 9.

Exploring the scope of 4sb and 12a lymph node dissection for cT2-4 lower third gastric cancer: Study protocol for a prospective cohort trial

Background

Currently, the extent of 4sb and 12a lymph node dissection is not clear and is based on the personal understanding of the surgeon. It may result in damage to the splenic artery and portal vein, leading to surgical complications. Therefore, this study aims to explore the scope of 4sb and 12a lymph node dissection in cT2-4 lower third gastric cancer.

Methods

This is an ongoing prospective cohort trial. The total sample size required for the trial (March 2022 to February 2025) is approximately 524 patients. The participants are divided into the experimental (4sb first branch and 12a anterior lymphadenectomy) or control groups (traditional 4sb and 12a lymphadenectomy). Electronic data capture systems will be used to collect demographic, laboratory test, auxiliary examination, operation, postoperative condition, postoperative pathology, and follow-up data. The primary outcome is the 12a lymph node metastatic rate. Secondary outcomes include the pathology (consisting of the 4sb lymph node metastatic rate, the number of 4sb lymph nodes dissected, the number of 12a lymph nodes dissected and tumor pathological staging), a safety evaluation index (consisting of complications and mortality ≤30 days after surgery), an efficacy evaluation (consisting of operation data and postoperative recovery status), and follow-up data (consisting of 3-year or 5-year disease-free survival and overall survival).

Discussion

By exploring the scope of 4sb and 12a lymph node dissection on the premise of ensuring radical cure of the tumor, the operation is simplified, the operation time is shortened, the damage of important blood vessels is reduced, the intraoperative and postoperative complications are reduced, and the patient recovers as soon as possible. Our study is a prospective exploration of the pathology, safety, efficacy, and prognosis of the new and traditional methods of 4sb and 12a lymph node dissection.

Trial registration

Chinese Clinical Trial Registry, ChiCTR2200057698 (registration date: March 15, 2022).

Surgical Merits of Open, Laparoscopic, and Robotic Gastrectomy Techniques with D2 Lymphadenectomy in Obese Patients with Gastric Cancer

BACKGROUND

Robotic surgery has been widely adopted for complex procedures to overcome technical limitations of open or laparoscopic methods. However, evidence of any subsequent benefit is lacking. This study was undertaken to compare open, laparoscopic, and robotic gastrectomy in technically demanding procedure-D2 dissection in obese patients with gastric cancer.

METHODS

Data collected between 2010 and 2018 on D2 gastrectomy in obese patients with gastric cancer were used to conduct retrospective analysis, comparing short- and long-term outcomes of open, laparoscopic, and robotic techniques.

RESULTS

In a total of 185 patients, there were 69 open, 62 laparoscopic, and 54 robotic gastrectomy procedures. Median ages for respective surgical groups were 66 (interquartile range [IQR]: 61-64 years), 63 (IQR: 59-63), and 59 years (IQR: 56-60 years) (p = 0.009). Early-stage gastric cancer ranked proportionately higher in the laparoscopic group (p = 0.005), but operative times were similar among groups. Estimated blood loss (p < 0.001) and drainage volumes (p = 0.001) were higher in the open group, relative to others. Although a robotic approach performed best in overall compliance and in mean number of retrieved lymph node, observed rates of early or late complications did not differ by technique. The open group experienced significantly poorer overall (p = 0.039) and relapse-free (p < 0.001) survival compared with the laparoscopic or robotic group. Robotic surgery emerged from multivariable Cox regression as a protective factor for relapse-free survival (HR = 0.314, 95% CI 0.116-0.851).

CONCLUSIONS

In obese patients with gastric cancer, robotic gastrectomy with D2 lymphadenectomy proved comparable to open or laparoscopic technique short-term, yielding better long-term outcomes.

Pattern of No. 12a lymph node metastasis in gastric cancer

Objective

The current standard D2 lymphadenectomy for gastric cancer (GC) includes dissection of lymph nodes (LNs) along the proper hepatic artery (No. 12a), however, the survival benefit remains controversial. The purpose of this study was to evaluate the pattern of No. 12a LN metastasis (LNM) in GC and explore the indications for No. 12a LN dissection.

Methods

Medical records of 413 consecutive GC patients who underwent curative surgery in Zhongshan Hospital, Fudan University between January 2015 and December 2018 were enrolled and reviewed retrospectively. The correlation between No. 12a LNM and clinicopathologic characteristics of patients was analyzed.

Results

The overall incidence of No. 12a LNM was 2.67% (11/413). Tumor location (P=0.012), depth of tumor infiltration (P<0.01) and N stage (P=0.018) were significant factors associated with No. 12a LNM. All the tumors with No. 12a LNM involved the lower third of the stomach and were in T3−4 stages. Patients with No. 12a LNM had extensive LNM than those without (20.91±4.25vs. 5.0±0.54, P<0.001). For advanced GC patients (stage III/IV) with tumors involving the lower third of the stomach, the incidence of No. 12a LNM increased to 10.7% (11/103). Patients with No. 12a LNM had a significantly poorer recurrence-free survival (RFS) (P=0.005) and overall survival (OS) (P=0.017). According to the result of multivariable Cox regression, No. 12a LNM was not an independent impact factor on RFS and OS.

Conclusions

The overall incidence of No. 12a LNM was low but it was much higher in GC patients who had very advanced tumors involving the lower third of the stomach. No. 12a LN dissection should be considered for these patients to improve the survival outcomes.

Intraoperative Surrogate Indicators of Gastric Cancer Patients' Long-Term Prognosis: The Number of Lymph Nodes Examined Relates to the Lymph Node Noncompliance Rate

BACKGROUND

The number of examined lymph nodes (ExLNs) and the rate of lymph node (LN) noncompliance are two independent indicators for evaluating the oncological efficacy for radical gastric cancer (GC) surgery. There are no studies to prove the relationship between these two indicators and their influence on the long-term prognosis of GC patients.

METHODS

The clinicopathological data of 1872 patients with radical GC resection with pathological stage pT2-4N0-3M0 from June 2007 to June 2013 were retrospectively analyzed. Noncompliance was defined as patients with more than one or more LN stations absence as described in the protocol for lymphadenectomy in the Japanese Gastric Cancer Association.

RESULTS

Among 1872 patients, 941 (50.3%) had complete LN compliance, 469 (25.1%) had minor LN noncompliance, and 462 (24.6%) had major LN noncompliance. Logistic regression analysis showed that cT staging and ExLNs were independent risk factors for LN noncompliance. In the whole group, Kaplan-Meier survival curve elucidated that overall survival (OS) differences of ExLNs ≤ 25 and ExLNs > 25 were statistically significant (p < 0.001). Stratified analysis of LN noncompliance elucidated no statistically significant difference in OS of these two group. Multivariate COX regression analysis suggested that LN noncompliance was an independent prognostic factor for OS, whereas ExLNs was no longer an independent prognostic factor for OS.

CONCLUSIONS

The increase number of ExLNs can improve the OS of GC patients, which depends on the decrease of LN noncompliance rate. As surrogate indicators for long-term prognosis of GC patients, LN noncompliance rate was better than ExLNs number.

Value of the preoperative prognostic nutritional index for the evaluation of patient prognosis after radical gastrectomy

Preoperative prognostic nutritional index (PNI) has been widely used for the clinical evaluation of patients with cancer. The present study assessed the prognostic value of preoperative PNI in patients after gastric cancer (GC) radical surgery. The clinical case and follow-up data of 170 patients undergoing GC radical surgery were retrospectively analyzed. The receiver operating characteristic (ROC) curve was used to compare the predictive ability of each inflammatory index: The PNI, neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR). The correlation between the preoperative PNI and overall survival (OS) was also analyzed via Kaplan-Meier (K-M) curves and multivariate Cox regression analyses. The results revealed that the optimal PNI cut-off was 46.030. According to this cut-off value, the whole sample was divided into PNI <46.030 (low PNI group) and PNI ≥46.030 (high PNI group). These groups were comprised of 102 and 68 cases, respectively. The area under the curve value of the PNI was 0.725, which was greater than that of traditional inflammatory indices, including the NLR and LMR. K-M survival analysis revealed that the 5 year survival rate of patients in the low PNI group was significantly lower than that of patients in the high PNI group (P<0.01). Univariate analysis and Cox multiple regression model analysis demonstrated that the T stage, N stage, pathological grade and PNI were independent risk factors for the 5 year survival rate after radical gastrectomy (P<0.05). In conclusion, the preoperative PNI is an independent risk factor for 5 year survival after radical gastrectomy and has clinical value for the prognostic evaluation of patients with GC.

Laparoscopic total gastrectomy for upper-middle advanced gastric cancer: analysis based on lymph node noncompliance

BACKGROUND

Increasing number of clinical studies have shown that laparoscopic distal gastrectomy (LDG) with D2 lymph node (LN) dissection is an effective method for the treatment of advanced gastric cancer (AGC). However, reports on the technical feasibility and oncology efficacy of laparoscopic total gastrectomy (LTG) in the treatment of AGC are rare.

METHODS

A retrospective analysis of the clinicopathologic data of 1313 patients with clinical stage of cT2-4aN0-3M0 undergoing laparoscopic radical gastrectomy with D2 LN dissection from June 2007 to December 2013 was performed. Noncompliance was defined as patients with more than one LN station absence as described in the protocol for D2 lymphadenectomy in the Japanese Gastric Cancer Association (JGCA). According to the literature, it was subdivided into LN compliance group (all LN stations were detected), minor LN noncompliance group (1-2 LN stations were not detected), major LN noncompliance group (more than 2 LN stations were not detected). Based on the LN noncompliance, the surgical indications of LTG were analyzed with LDG as control.

RESULTS

Among the 1313 patients, 197 (39.20%) patients and 321(39.71%) patients in the LDG group and the LTG group had minor LN noncompliance, 59(11.70%) patients and 163(20.10%) patients had major LN noncompliance. The difference in the extent of LN noncompliance between the two groups was statistically significant (p < 0.001). COX proportional hazards regression analysis elucidated that the LN noncompliance was an independent prognostic factor for overall survival (OS). BMI ≥ 25 kg/m² and the history of previous abdominal surgery (PAS) were independent risk factors for major LN noncompliance in LTG group (p < 0.05), with which patients were defined as a LN noncompliance high-risk group. With the exception of LN noncompliance high-risk group, the difference in the extent of LN noncompliance between LTG group and LDG group was still statistically significant (p = 0.008). Tumor diameter > 60 mm is a preoperative risk factor for station #5 LN noncompliance, and no preoperative risk factors for station #6 LN noncompliance were found, with which patients were defined as LN noncompliance middle-risk group.

CONCLUSION

LN noncompliance is an independent prognostic factor for poor prognosis in patients after LTG. Based on this finding, patients with BMI ≥ 25 kg/m², history of PAS and tumor diameter > 60 mm in the advanced stage of upper-middle gastric cancer represent high/middle-risk groups with LN noncompliance in LTG surgery, which should be carefully selected.