Comparison of different methods of splenic hilar lymph node dissection for advanced upper- and/or middle-third gastric cancer

Splenic hilar lymph node dissection enhances survival in Bormann type 4 gastric cancer

Splenic hilar (no.10) lymph node dissection during total gastrectomy is no longer recommended for advanced proximal gastric cancer. However, the treatment efficacy of no.10 lymph node dissection in Borrmann type 4 tumors remains unclear. We enrolled 539 patients who underwent total gastrectomy for Borrmann type 4 tumors between 2006 and 2016 in four major institutions in Korea. We compared the long-term survival of the no.10 lymph node dissection (n = 309) and no-dissection groups (n = 230) using the propensity score (inverse probability of treatment weighting). The treatment effects of no.10 lymph node dissection were estimated in the weighted sample using the Cox proportional hazards regression model with a robust sandwich-type variance estimator. After inverse probability of treatment weighting, there were 540.4 patients in the no.10 lymph node dissection group and 532.7 in the no-dissection group. The two groups showed well-balanced baseline characteristics, including tumor node metastasis stage. The 5-year survival rates in the no.10 lymph node dissection and no-dissection groups were 45.7% and 38.6%, respectively (log-rank p = 0.036, hazard ratio 0.786, 95% confidence interval 0.630-0.982). Multivariate analysis revealed that no.10 lymph node dissection was an independent favorable prognostic factor (adjusted hazard ratio 0.747, 95% confidence interval 0.593-0.940) after adjusting for other prognostic factors. Sensitivity analyses in other inverse probability of treatment weighting models and the propensity score matching model showed similar results. Patients undergoing no.10 lymph node dissection showed improved survival compared to those without. No.10 lymph node dissection is recommended during total gastrectomy for patients with Borrmann type 4 gastric cancer.

Ex Situ In Vivo Technique of Spleen-Preserving Splenic Hilar Lymph Node Dissection in Operable Proximal Gastric Adenocarcinoma

D2 gastrectomy is the globally accepted standard surgical procedure for operable gastric cancer, and lymph node (LN) dissection is considered as the critical part of radical surgery and closely related to the prognosis. The splenic hilar LN (SHLN) or level 10 are to be removed during standard D2 total gastrectomy. In situ and ex situ spleen-preserving lymphadenectomies have been the most common dissection approaches for SHLNs. No study exists which compares the outcomes of these techniques in Indian population. This study is aimed to analyse the operative outcomes of ex situ in vivo technique of spleen-preserving splenic hilar lymph node dissection in patients who underwent D2 total gastrectomy for operable proximal gastric cancer in comparison with in situ in vivo technique of splenic hilar lymph node dissection. We reviewed prospectively collected data from 17 patients with operable proximal gastric cancer between September 2016 and April 2019 who underwent D2 total gastrectomy with splenic hilar lymph node dissection and studied the preoperative demographic factors, operative and postoperative outcomes comparing the different operative techniques. Patients with oesophago-gastric junction involvement, direct splenic or other adjacent organ invasion requiring multivisceral resection and gastric stump carcinoma were excluded. Overall, 17 patients underwent D2 total gastrectomy for operable gastric cancer. Mean age of presentation was 54.7 years including 13 males and 4 females. Five patients had middle third and 12 patients had upper third cancer. All patients had splenic hilar nodal clearance as follows: in situ - 14 and ex situ - 3 patients. R0 resection was achieved in all patients. Lymph node harvest tends to be higher with lower operative time and blood loss in patients with ex situ technique compared to in situ technique with similar morbidity. Ex situ in vivo technique of spleen-preserving splenic hilar lymph node dissection can be considered as both safe and feasible procedure for operable proximal gastric cancer patients in experienced centres to achieve better lymph node yield with no significant increase in morbidity.

Is splenic hilar lymph node dissection necessary for proximal gastric cancer surgery?

Advanced proximal gastric cancer sometimes metastasizes to the splenic hilar lymph nodes (No. 10 LN). Total gastrectomy combined with splenectomy is performed for complete removal of the No. 10 LN and was historically a standard procedure in Japan. However, splenectomy is associated with several disadvantages for patients, such as increased postoperative morbidity, risk of thrombogenic disease, fatal infection from encapsulated bacteria, and the development of other types of cancer in the long term because of loss of immune function. Therefore, splenectomy should only be performed when its estimated oncological effect exceeds such disadvantages. A Japanese randomized controlled trial (JCOG0110) clearly demonstrated that prophylactic splenectomy is not necessary unless the tumor has invaded the greater curvature; thus, splenectomy is no longer routinely performed in Japan. However, several retrospective studies have shown a comparatively high incidence of No. 10 LN metastasis and therapeutic value from LN dissection at that station in the tumors invading the greater curvature. Similar tendencies have also been reported in type 4 or remnant gastric cancer involving the greater curvature. In view of these facts, No. 10 LN dissection is presently recommended for such patients; however, robust evidence is lacking. In recent years, laparoscopic/robotic spleen-preserving splenic hilar dissection utilizing augmented visualization without pancreatic mobilization has been developed. This procedure is expected to replace prophylactic splenectomy and provide an equal oncological effect with lower morbidity. In Japan, a prospective phase-II study (JCOG1809) is currently ongoing to investigate the safety and feasibility of this procedure.

Risk Factors for the Severity of Complications in Minimally Invasive Total Gastrectomy for Gastric Cancer: a Retrospective Cohort Study

Purpose

Minimally invasive gastrectomy is a promising surgical method with well-known benefits, including reduced postoperative complications. However, for total gastrectomy of gastric cancers, this approach does not significantly reduce the risk of complications. Therefore, we aimed to evaluate the incidence and risk factors for the severity of complications associated with minimally invasive total gastrectomy for gastric cancer.

Materials and Methods

The study included 392 consecutive patients with gastric cancer who underwent either laparoscopic or robotic total gastrectomy between 2011 and 2019. Clinicopathological and operative characteristics were assessed to determine the features related to postoperative complications after minimally invasive total gastrectomy. Binomial and multinomial logistic regression models were used to identify the risk factors for overall complications and mild and severe complications, respectively.

Results

Of 103 (26.3%) patients experiencing complications, 66 (16.8%) and 37 (9.4%) developed mild and severe complications, respectively. On multivariate multinomial regression analysis, independent predictors of severe complications included obesity (OR, 2.56; 95% CI, 1.02−6.43; P=0.046), advanced stage (OR, 2.90; 95% CI, 1.13−7.43; P=0.026), and more intraoperative bleeding (OR, 1.04; 95% CI, 1.02−1.06; P=0.001). Operation time was the only independent risk factor for mild complications (OR, 1.06; 95% CI, 1.001−1.13; P=0.047).

Conclusions

The risk factors for mild and severe complications were associated with surgery, indicating surgical difficulty. Surgeons should be aware of these potential risks that are related to the severity of complications so as to reduce surgery-related complications after minimally invasive total gastrectomy for gastric cancer.

The Retropancreatic Fusion Fascia Oriented Splenic Hilar Lymphadenectomy Versus Laparoscopic Approach In D2 Total Gastrectomy

BACKGROUND The retropancreatic fusion fascia is recognized as the anatomical landmark during retropancreatic mobilization. However, its role in D2 total gastrectomy for proximal advanced gastric cancer (PAGC) remains unexplored. This study aimed to develop the retropancreatic fusion fascia-oriented ex vivo approach for splenic hilar lymphadenectomy (RP-SL) to avoid difficulty in using the total laparoscopic approach (TL-SL). MATERIAL AND METHODS The data for patients with PAGC who underwent D2 total gastrectomy were retrieved from our clinical database and electronic medical records (December 2016 to December 2018), with a 1:1 match ratio for balance of the 2 groups. RESULTS In sum, 84 matched patients were included in the study. There were 2360 retrieved lymph nodes (LNs), with an average of 28.10. Sixteen patients were confirmed with positive splenic hilar lymphadenectomy, and the mean harvested lymph nodes (LNs) were significantly increased in the RP-SL group compared to the TL-SL group (3.07 vs. 2.29, P<0.001), decreased operative time (193.21 min vs. 247.74 min, P<0.001), and less blood loss (96.90 mL vs. 185.24 mL, P=0.001) in the RP-SL group. Postoperative hospital stay (6.55 days vs. 7.26 days), rate of morbidity (9.50% vs. 11.91%), and overall costs (¥65255.64 vs. ¥64419.91) were comparable between the groups (P>0.05).  CONCLUSIONS The landmark at the conjunction between the superior mesenteric vessels and the inferior pancreatic margin made it feasible to identify the retropancreatic areolar. The RP-SL approach was safe and efficient for splenic hilar lymphadenectomy.

Advantages of Splenic Hilar Lymph Node Dissection in Proximal Gastric Cancer Surgery

Gastrectomy with lymph node dissection remains the gold standard for curative treatment of gastric cancer. Dissection of splenic hilar lymph nodes has been included as a part of D2 lymph node dissection for proximal gastric cancer. Previously, pancreatico-splenectomy has been performed for dissecting splenic hilar lymph nodes, followed by pancreas-preserving splenectomy and spleen-preserving lymphadenectomy. However, the necessity of routine splenectomy or splenic hilar lymph node dissection has been under debate due to the increased morbidity caused by splenectomy and the poor prognostic feature of splenic hilar lymph node metastasis. In contrast, the relatively high incidence of splenic hilar lymph node metastasis, survival advantage, and therapeutic value of splenic hilar lymph node dissection in some patient subgroups, as well as the effective use of novel technologies, still supports the necessity and applicability of splenic hilar lymph node dissection. In this review, we aimed to evaluate the need for splenic hilar lymph node dissection and suggest the subgroup of patients with favorable outcomes.

Disadvantages of Complete No. 10 Lymph Node Dissection in Gastric Cancer and the Possibility of Spleen-Preserving Dissection: Review

Splenic hilar lymph node dissection has been the standard treatment for advanced proximal gastric cancer. Splenectomy is typically performed as part of this procedure. However, splenectomy has some disadvantages, such as increased risk of postoperative complications, especially pancreatic fistula. Moreover, patients who underwent splenectomy are vulnerable to potentially fatal infection caused by encapsulated bacteria. Furthermore, several studies have shown an association of splenectomy with cancer development and increased risk of thromboembolic events. Therefore, splenectomy should be avoided if it does not confer a distinct oncological advantage. Most studies that compared patients who underwent splenectomy and those who did not failed to demonstrate the efficacy of splenectomy. Based on the results of a randomized controlled trial conducted in Japan, prophylactic dissection with splenectomy is no longer recommended in patients with gastric cancer with no invasion of the greater curvature. However, patients with greater curvature invasion or those with remnant gastric cancer still need to undergo splenectomy to facilitate splenic hilar node dissection. Spleen-preserving splenic hilar node dissection is a new procedure that may help delink splenic hilar node dissection and splenectomy. In this review, we examine the evidence pertaining to the efficacy and disadvantages of splenectomy. We discuss the possibility of spleen-preserving surgery for prophylactic splenic hilar node dissection to overcome the disadvantages of splenectomy.

Laparoscopic splenic hilar lymph node dissection for advanced gastric cancer: to be or not to be

The incidence of proximal gastric cancer has increased in both the East and the West. Although some novel reconstructions like double-tract or double-flap anti-reflux procedure related to proximal gastrectomy are promising, total radical gastrectomy still accounts for a significant portion of these procedures. D2 radical gastrectomy is the globally accepted standard surgical procedure for advanced gastric cancer, and lymph node (LN) dissection is considered as the critical point of radical surgery and closely related to the prognosis. The splenic hilar LNs (No. 10) are LNs that need to be removed during standard D2 surgery for proximal and total gastrectomy. Lymphadenectomy does not only provide valuable information on the prognosis of gastric cancer, but the thoroughness of the sweep itself is directly related to postoperative survival. The incidence of splenic hilar LN (No. 10) metastasis rate is not high. Although the LN metastasis pathway around the spleen is complicated, the feasibility of laparoscopic splenic hilar LN dissection in locally advanced gastric cancer has been verified. However, these results are mostly from small volume clinical studies, and the fact is that the dissection of the splenic hilar is technique-demanding even for open surgery. The rational strategy for LN dissection for surgeons is still controversial. For splenic LN dissection in radical gastric cancer surgery, whether to select individualized splenic LN dissection for those patients highly suspected of clinical metastasis or to advocate the evidence-based strategy and neglect dissection in lower risk patients to avoid over-removing of LNs, is a vital question that needs to be clarified.

Prognostic Impact of Extended Lymph Node Dissection versus Limited Lymph Node Dissection on pN0 Proximal Advanced Gastric Cancer: a Propensity Score Matching Analysis

Purpose

Splenic hilar lymph node dissection (LND) during total gastrectomy is regarded as the standard treatment for proximal advanced gastric cancer (AGC). This study aimed to investigate whether splenic hilar LND or D2 LND is essential for proximal AGC of pT2-4aN0M0 stage.

Materials and Methods

Data of curative total gastrectomies (n=370) performed from 2000 to 2010 for proximal AGC of pT2-4aN0 stage were retrospectively reviewed. Clinicopathological characteristics and long-term outcomes were compared using propensity score matching between patients who underwent splenectomy (n=43) and those who did not (n=327) and between patients who underwent D2 LND (n=122) and those who underwent D1+ LND (n=248).

Results

Tumors of larger size and a more advanced T stage and significantly lower overall and relapse-free survival (P<0.001) were observed in the splenectomy group than in the 2 spleen-preserving groups. Before propensity score matching, worse overall and relapse-free survival (P<0.001) was observed in the splenectomy group than in the non-splenectomy group. After matching, although the overall survival became similar (P=0.123), relapse-free survival was worse in the splenectomy group (P=0.021). Compared with D1+ LND, D2 LND had no positive impact on the overall (P=0.619) and relapse-free survival (P=0.112) after propensity score matching.

Conclusions

Splenic hilar LND with or without splenectomy may not have an oncological benefit for patients with pathological AGC with no LN metastasis.