Prognostic implications of lymphadenectomy in esophageal cancer after neo-adjuvant therapy: a single center experience

Number of Resected Lymph Nodes and Survival Status in Node-Negative Esophageal Squamous Cell Carcinoma: A Cohort Study

Objective

To explore the association between survival status and the number of resected lymph nodes in node-negative esophageal squamous cell carcinoma(ESCC) after surgical treatment.

Methods

This was a retrospective observational cohort study and data were obtained from the Surveillance, Epidemiology, and End Results program (SEER) and TaiZhou hospital in China. The data for subjects with negative lymph nodes and no distant metastasis (pN0M0) after post-operative pathology were screened. The nonlinear relationship between resected lymph node number and survival status in node-negative ESCC was conducted using restricted cubic spline regression analysis. The association between the number of resected lymph nodes and survival status in node-negative ESCC was evaluated by Cox proportional hazards regression models. Subgroup analysis based on different subgroups was also performed.

Results

A total of 999 subjects were included in the study. Restricted cubic spline regression was used to show a U shaped association between the number of resected lymph nodes and survival status in node-negative ESCC, with low count associated with a decreased survival. To elucidate the association, we adjusted for age, sex, race, T stage, TNM (tumor node metastasis classification), location, grade, chemotherapy, and radiotherapy. As the resected lymph node number increased by one node, the survival status was improved by 2% (Hazard ratio(HR) = 0.98, 95% confidence interval (CI) 0.98-0.99). Sensitivity analysis indicate that the effect size and direction in different subgroups are consistent, the results is stability in SEER.

Conclusion

A low count of resected lymph nodes correlated with reduced survival in patients with ESCC, where resecting 25 to 28 or more nodes is considered optimal. Larger prospective studies are warranted to confirm these findings.

Lymphadenectomy and Survival After Neoadjuvant Chemoradiation for Esophageal Adenocarcinoma: Is More Better?

PURPOSE

The purpose of this study was to assess the impact of number of lymph nodes examined on survival in patients with esophageal adenocarcinoma who underwent neoadjuvant chemoradiation.

METHODS

The National Cancer Database was queried for patients who underwent neoadjuvant chemoradiation followed by surgery for esophageal adenocarcinoma. Propensity scores were created predicting the odds of undergoing resection of ≥ 25 nodes. Patients were matched on propensity score. Overall survival analyses were performed using the Kaplan-Meier method. Sensitivity analyses were performed using various nodal cutoffs.

RESULTS

In total, 3953 patients who underwent neoadjuvant chemoradiation were identified. The median number of resected nodes was 14 nodes (IQR, 8-20 nodes). Resection of ≥ 15 (vs. < 15 nodes: 32 vs. 26 months; p < 0.001), ≥ 20 (vs. < 20 nodes: 36 vs. 28 months; p = 0.001), and ≥ 25 (vs. < 25 nodes: 37 vs. 29 months; p = 0.015) nodes was associated with higher median survival, but resection of ≥ 30 nodes was not (vs. < 30 nodes: 41 vs. 33 months; p = 0.367). Resection of ≥ 25 lymph nodes remained predictive for improved survival on subset analysis in patients with negative nodes and who underwent treatment at high-volume centers.

CONCLUSIONS

After neoadjuvant chemoradiation, resection of 25 or more lymph nodes was associated with longer median survival. Prospective trials are warranted to determine the optimal nodal yield after neoadjuvant chemoradiation.

The Value of Lymphadenectomy Post-Neoadjuvant Therapy in Carcinoma Esophagus: a Review

Lymph nodal metastasis is one of the most important prognostic factors determining survival in patients with carcinoma esophagus. Radical esophagectomy, with the resection of surrounding lymph nodes, is considered the prime treatment of carcinoma esophagus. An extensive lymphadenectomy improves the accuracy of staging and betters locoregional control, but its effect on survival is still not apparent and carries the disadvantage of increased morbidity. The extent of lymphadenectomy during esophagectomy also remains debatable, with many studies revealing contradictory results, especially in the era of neoadjuvant therapy. The pattern of distribution and the number of nodal metastasis are modified by neoadjuvant therapy. The paper reviews the existing evidence to determine whether increased lymph node yield improves oncological outcomes in patients undergoing esophagectomy with particular attention to those patients receiving neoadjuvant therapy.

Does the lymph node yield affect survival in patients with esophageal cancer receiving neoadjuvant therapy plus esophagectomy? A systematic review and updated meta-analysis

BACKGROUND

Conflicting data have been reported on the prognostic impact of the extent of lymphadenectomy during esophagectomy for esophageal cancer (EC) after neoadjuvant therapy, especially after neoadjuvant chemoradiotherapy (nCRT).

METHODS

A comprehensive online search was performed to explore the association between increased lymph node yield (LNY) and survival of patients with EC, in which the overall survival (OS) was set as the primary outcome. In addition to analysis of the entire cohort, subgroup analyses of different induction therapy and different populations were also performed.

FINDINGS

A total of 19528 patients from twelve studies were included in our study. The pooled data revealed that more lymph node harvested was associated with better OS (HR = 0·87; 95% CI: 0·79-0·95, p < 0·001). Notably, a higher LNY was associated with better OS if the threshold was less than 18. However, more thorough lymphadenectomy might not bring additional survival benefits when it came to a cutoff value more than 18. The subgroup analysis further revealed that a higher LNY after nCRT was associated favorable survival. In terms of subset analysis of different populations, increased LNY was associated with longer OS in Western populations but not in Eastern.

INTERPRETATION

Increased LNY during esophagectomy after neoadjuvant therapy, especially after nCRT, might be associated with improved OS. More studies are warranted to assess the survival benefits of a higher LNY receiving neoadjuvant therapy plus esophagectomy, especially in Eastern populations.

FUNDING

Supported by the projects from Suzhou Key Laboratory of Thoracic Oncology (SZS201907), Suzhou Key Discipline for Medicine (SZXK201803), the Science and Technology Research Foundation of Suzhou Municipality (SYS2018063, SYS2018064), Municipal Program of People's Livelihood Science and Technology in Suzhou (SS2019061) and Major Project for Social Development, Jiangsu Provincial Department of Science and Technology (SBE2020750085).

Prognostic Value of Lymph Node Yield on Overall Survival in Esophageal Cancer Patients: A Systematic Review and Meta-analysis

OBJECTIVE

This meta-analysis determines whether increased lymph node yield improves survival in patients with esophageal cancer undergoing esophagectomy with or without neoadjuvant therapy.

BACKGROUND

Esophagectomy involves resection of the esophagus and surrounding lymph nodes, which are commonly the first stations of cancer spread. The extent of lymphadenectomy during esophagectomy remains controversial, with several studies publishing conflicting results, especially in the era of neoadjuvant therapy.

METHODS

An electronic literature search was undertaken using Embase, Medline, and the Cochrane library databases (2000 to 2017). Articles with esophageal cancer patients undergoing esophagectomy with lymphadenectomy and investigating the effects of low and high lymph node yield on overall survival and disease-free survival were included. Meta-analysis of data was conducted using a random effects model. If the study divided the cohort into multiple groups based on lymph node yield, survival was compared between the lowest and highest lymph node yield groups. In addition to analysis of the entire cohort, subset analysis of only those patients receiving neoadjuvant therapy was also performed.

RESULTS

A total of 26 studies were included in this meta-analysis with a follow-up ranging from 15 to 94 months. For the analysis of overall survival, 23 studies were included. A meta-analysis showed that overall survival significantly improved in the high lymph node yield group [hazard ratio (HR) = 0.81; 95% confidence interval (95% CI) = 0.74-0.87; P < 0.01]. In the 10 studies describing disease-free survival, this was significantly improved in the high lymph node yield group (HR = 0.72; 95% CI = 0.62-0.84; P < 0.01). Subset analysis of neoadjuvant-treated patients demonstrated a survival benefit of high lymph node yield on overall survival (HR = 0.82; 95% CI = 0.73-0.92; P < 0.01).

CONCLUSION

This meta-analysis demonstrates the benefit of an increased lymph node yield from esophagectomy on overall and disease-free survival. In addition, a survival benefit of a high lymph node yield was demonstrated in patients receiving neoadjuvant therapy followed by esophagectomy.

Therapeutic value of lymph node dissection for esophageal squamous cell carcinoma after neoadjuvant chemotherapy

BACKGROUND AND OBJECTIVES

The optimal extent of lymphadenectomy in patients with esophageal cancer is controversial. This study aimed to examine the therapeutic value of lymph node (LN) dissection for each LN station in patients with esophageal squamous cell carcinoma (ESCC) who receive neoadjuvant chemotherapy.

METHODS

In 304 patients with ESCC who underwent neoadjuvant chemotherapy, Efficacy Index (EI) was calculated by multiplying the incidence of metastasis by the 3-year survival rate of patients with positive nodes for each LN station.

RESULTS

Prognosis was better in responders to neoadjuvant chemotherapy than non-responders (3-year survival; 66.3% vs 48.1%, P = 0.0035). The total number of resected LNs did not affect survival although the number of positive LNs did. The number of resected LNs did not correlate with the number of metastatic LNs. Cardiac LN and recurrent nerve LN showed high EI, irrespective of tumor location. EI for each LN station did not vary according to the response to neoadjuvant therapy.

CONCLUSIONS

The present study showed that therapeutic value of each LN was not affected by preoperative chemotherapy. The location of resected LNs rather than the total number of resected LNs may be more important to maximize the survival benefit of lymphadenectomy.

Lymph node retrieval during esophagectomy with and without neoadjuvant chemoradiotherapy: prognostic and therapeutic impact on survival

OBJECTIVES

We aimed to examine the association between total number of resected nodes and survival in patients after esophagectomy with and without nCRT.

BACKGROUND

Most studies concerning the potentially positive effect of extended lymphadenectomy on survival have been performed in patients who underwent surgery alone. As nCRT is known to frequently "sterilize" regional nodes, it is unclear whether extended lymphadenectomy after nCRT is still useful.

METHODS

Patients from the randomized CROSS-trial who completed the entire protocol (ie, surgery alone or chemoradiotherapy + surgery) were included. With Cox regression models, we compared the impact of number of resected nodes as well as resected positive nodes on survival in both groups.

RESULTS

One hundred sixty-one patients underwent surgery alone, and 159 patients received multimodality treatment. The median (interquartile range) number of resected nodes was 18 (12-27) and 14 (9-21), with 2 (1-6) and 0 (0-1) resected positive nodes, respectively. Persistent lymph node positivity after nCRT had a greater negative prognostic impact on survival as compared with lymph node positivity after surgery alone. The total number of resected nodes was significantly associated with survival for patients in the surgery-alone arm (hazard ratio per 10 additionally resected nodes, 0.76; P=0.007), but not in the multimodality arm (hazard ratio 1.00; P=0.98).

CONCLUSIONS

The number of resected nodes had a prognostic impact on survival in patients after surgery alone, but its therapeutic value is still controversial. After nCRT, the number of resected nodes was not associated with survival. These data question the indication for maximization of lymphadenectomy after nCRT.