Lymph Node Yield in Colon Cancer: Individuals Can Make the Difference

Intracorporeal anastomosis could be associated with a higher lymph node yield in right colon cancer surgery: Results of the ICA-LATAM study, a retrospective, multicentre, comparative analysis in Latin America

AIM

The aim of this work was to compare lymph node (LN) yield in patients operated on for right colon cancer (RCC) using a laparoscopic approach between those receiving an intracorporeal (ICA) or extracorporeal anastomosis (ECA).

METHOD

This is a retrospective multicentre study involving patients operated on for RCC in nine tertiary referral centres in Latin America during a 2-year period. The main comparative outcome between groups was the number of LNs harvested between groups.

RESULTS

The study included 416 patients, 261 (62.7%) in the ECA group and 155 (37.3%) in the ICA group. Patients in the ECA group were elderly (66 vs. 61 years, p < 0.001). Patients receiving an ICA achieved a significantly higher LN yield than those receiving an ECA (24 vs. 18, p < 0.001). This group also had a lower percentage of patients achieving a substandard LN yield (<12 LNs) (10% vs. 24.8%, p = 0.001) and more patients achieving a high number of harvested LNs (>32 LNs) (15.5% vs. 8.3%, p = 0.039). In the multivariate analysis, ICA was independently related to the primary outcome (LN yield) (OR 3.28, p = 0.027, 95% CI 1.14-9.38).

CONCLUSION

In this retrospective study, patients operated on for RCC who received an ICA achieved a higher LN yield. Further studies are needed to reconfirm these findings, and also to find an explanation for these results.

The effect of preoperative endoscopic tattooing using India ink on lymph node yield in laparoscopic colectomy for stage I right-sided colon cancer

PURPOSE

The purpose of this study is to evaluate the effect of preoperative endoscopic tattooing using India ink (ETI) on the number of retrieved lymph nodes (LNs) dissected during laparoscopic surgery for stage I right-sided colon cancer (RCC).

METHODS

This single-center, retrospective study included stage I RCC patients who underwent laparoscopic surgery between January 2010 and December 2021. The clinicopathological background and number of LNs retrieved were compared between patients managed with and without ETI. A multiple linear regression analysis was used to examine the effect of independent variables on the LN yield.

RESULTS

A total of 169 patients were enrolled. Of these, 89 patients (52.7%) were classified into the ETI group, and 80 (47.3%) were classified into the no-ETI group. There were no significant differences in age, sex, body mass index, or tumor progression between the two groups. A univariate analysis showed that the number of LNs retrieved was significantly higher in female (26 vs. 24, p = 0.026), with tumor localization in the ascending or transverse colon (20 in the cecum, 26 in the ascending colon, 27 in the transverse colon, p < 0.001), and with preoperative ETI (28 vs. 21, p < 0.001). In a multivariate linear regression analysis, female sex (p = 0.0011), D3 lymphadenectomy (p = 0.046), and preoperative ETI (p = 0.012) were independently associated with the LN yield.

CONCLUSION

In laparoscopic surgery for stage I RCC, preoperative ETI increased the number of LNs retrieved and allowed for appropriate staging.

How does lymph node yield affect survival outcomes of stage I and II colon cancer?

Background

According to the American Joint Committee on Cancer staging for cancer of the colon, a minimum of 12 lymph nodes (LN) has to be sampled for accurate staging. This has bearing on the long-term prognosis and the need for adjuvant chemotherapy. The aim of this study was to revisit the association of lymph node yield and the long-term survival in patients with stages I and II, i.e. node-negative, colon cancer.

Method

Consecutive patients who underwent elective or emergency curative resections for cancer of colon between the years 2003 and 2012 were retrospectively reviewed. Only patients with stage I or II diseases (AJCC 8th edition) were included. They were analysed in three groups, LN<12, LN12-19 and LN≥20. Their clinic-pathological characteristics were compared. The disease-free (DFS) and overall survival (OS) were estimated with the Kaplan-Meier method and compared with the log-rank test.

Results

There was a total of 659 patients included in the analysis. Twelve or more LN were found in 65.6% of the specimens. The mean follow-up was 83.9 months. LN≥20 had significantly better DFS (p = 0.015) and OS (p = 0.036), whereas LN<12 had similar DFS and OS when compared to LN12-19. The advantage in DFS and OS were mainly seen in those with stage II diseases. A lymph node yield of greater than 20 was one of the predictors of favourable DFS, hazard ratio 0.358; 95% CI 0.170–.756, p = 0.007.

Conclusion

The lymph node yield had a significant association with survival outcomes. A lymph node yield of 20 or more was associated with better survival outcomes. On the other hand, lymph node yield less than 12 was not shown to have inferior survival outcomes when compared to those between 12 and 19.

Compliance to D2 lymphadenectomy in laparoscopic gastrectomy

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

Survival after resection of appendiceal carcinoma by hemicolectomy and less radical than hemicolectomy: a population-based propensity score matched analysis

AIM

The operative treatment for non-metastatic appendiceal carcinoma is controversial despite the recommendation of right hemicolectomy (RH) by many researchers. The aim of this population-based study was to compare outcomes after RH and less radical resection than right hemicolectomy (LRH).

METHOD

A total of 1144 patients who underwent resection with additional lymphadenectomy of Stages I-III appendiceal carcinoma from 2004 to 2012 were identified in the Surveillance, Epidemiology and End Results database. Overall survival (OS) and cancer-specific survival (CSS) after RH and LRH were assessed by unadjusted and risk-adjusted Cox regression analysis and by propensity score matched analysis.

RESULTS

A total of 855 (74.7%) patients underwent RH and 289 (25.3%) underwent LRH. In an unadjusted analysis, survival after LRH and RH did not differ in OS [hazard ratio (HR) 0.95, 95% CI 0.71-1.26, P = 0.707] and CSS (HR 0.95, 95% CI 0.69-1.32, P = 0.762). The 5-year OS and CSS in patients who underwent RH were 71.6% (95% CI 67.8-75.6%) and 76.4% (95% CI 72.8-80.3) compared with 73.8% (95% CI 67.9-80.2) and 78.7% (95% CI 73.2-84.7) in patients with LRH, respectively. No relevant difference in survival between LRH and RH could be observed in a multivariable analysis (OS, HR 0.90, 95% CI 0.65-1.25, P = 0.493; CSS, HR 0.87, 95% CI 0.60-1.26, P = 0.420) and after propensity score adjusted analysis (OS, HR 0.87, 95% CI 0.62-1.22, P = 0.442; CSS, HR 0.97, 95% CI 0.67-1.40, P = 0.883).

CONCLUSIONS

In this retrospective analysis, survival after RH for non-metastatic appendiceal carcinoma was not statistically significantly superior to LRH. Hence, LRH with lymphadenectomy might be sufficient for treatment of non-metastatic appendiceal carcinoma.