Prognostic value of lymph node count on survival in pathologically node-negative oesophageal squamous cell cancer

The optimal number of lymph node dissections in three-field lymphadenectomy for esophageal squamous cell carcinoma: a large retrospective study

BACKGROUND

Currently, there is no consensus on the optimal number of lymph node dissections (LNDs) in three-field lymphadenectomy for esophageal squamous cell carcinoma (ESCC). This study aimed to explore the relationship between the LND count and overall survival (OS) in ESCC patients to determine the optimal number of LNDs that confer a survival benefit.

METHODS

A retrospective analysis was conducted on ESCC patients who underwent three-field lymphadenectomy at Fujian Cancer Hospital from February 2004 to January 2018. The optimal LND number was determined using X-Tile software. Kaplan‒Meier survival curves and Cox regression analyses were used to evaluate the relationship between LND count and OS.

RESULTS

A total of 1053 ESCC patients who underwent three-field lymphadenectomy were included in this study (median age 58 years [IQR: 52-65], 781 males [74.2%]). Using X-Tile software, 27 was identified as the optimal cutoff value for the number of LNDs. The 5-year OS for the > 27 LNDs group was significantly better than that for the ≤ 27 LNDs group (67.8% vs. 59.8%, P = 0.042). Multivariate Cox regression analysis confirmed that LND count (≤ 27 and > 27) was an independent protective factor for OS (HR = 0.724; P = 0.004). Stratified analysis on the basis of TNM stage revealed that in patients with T3-4N0M0 disease (HR = 0.412; P = 0.001) and T1-2 N + M0 disease (HR = 0.503; P = 0.025), a greater number of dissected lymph nodes was closely associated with a survival benefit.

CONCLUSION

For ESCC patients undergoing three-field lymphadenectomy, dissecting more than 27 lymph nodes is associated with better prognosis, especially for patients with T3-4N0M0 and T1-2 N + M0 stages.

Sex differences in survival following surgery for esophageal cancer: A systematic review and meta-analysis

The impact of sex on the prognosis of patients with esophageal cancer remains unclear. Evidence supports that sex- based disparities in esophageal cancer survival could be attributed to sex- specific risk exposures, such as age at diagnosis, race, socioeconomic status, smoking, drinking, and histological type. The aim of our study is to investigate the role of sex disparities in survival of patients who underwent surgery for esophageal cancer. A systematic review and meta-analysis of the existing literature in PubMed, EMBASE, and CENTRAL from December 1966 to February 2023, was held. Studies that reported sex-related differences in survival outcomes of patients who underwent esophagectomy for esophageal cancer were identified. A total of 314 studies were included in the quantitative analysis. Statistically significant results derived from 1-year and 2-year overall survival pooled analysis with Relative Risk (RR) 0.93 (95% Confidence Interval (CI): 0.90-0.97, I2 = 52.00) and 0.90 (95% CI: 0.85-0.95, I2 = 0.00), respectively (RR < 1 = favorable for men). In the postoperative complications analysis, statistically significant results concerned anastomotic leak and heart complications, RR: 1.08 (95% CI: 1.01-1.16) and 0.62 (95% CI: 0.52-0.75), respectively. Subgroup analysis was performed among studies with <200 and > 200 patients, histology types, study continent and publication year. Overall, sex tends to be an independent prognostic factor for esophageal carcinoma. However, unanimous results seem rather obscure when multivariable analysis and subgroup analysis occurred. More prospective studies and gender-specific protocols should be conducted to better understand the modifying role of sex in esophageal cancer prognosis.

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.

Association of survival with adjuvant radiotherapy for pN0 esophageal cancer

INTRODUCTION

This study was conducted to elucidate the link between adjuvant radiotherapy and survival in pathologic node-negative (pN0) esophageal cancer patients with upfront esophagectomy.

METHODS

From 2000 to 2016, patients with pN0 esophageal cancer who underwent upfront esophagectomy were selected from the Surveillance, Epidemiology, and End Results (SEER) database. The association of high-risk covariates with survival after adjuvant radiotherapy was evaluated using propensity score matching and multivariate analysis.

RESULTS

We identified 3197 patients, 321 (10.0%) underwent postoperative radiotherapy and 2876 (90.0%) underwent esophagectomy alone. In the unmatched cohort, postoperative radiotherapy was associated with a statistically significant but modest absolute decrease in survival outcomes (P < 0.001). In the matched cohort, the survival differences disappeared. Additionally, adjuvant radiotherapy was linked to a 5-year overall survival (OS) benefit for patients with the pT3-4N0 disease (34.8% vs. 27.7%; P = 0.008). Adjuvant radiotherapy for pT3-4N0 disease with tumor length ≥3 cm, adenocarcinoma, and evaluated lymph node count <12 was shown to independently function as a risk factor for improved OS, as per a multivariate analysis (P < 0.01).

CONCLUSIONS

This population-based trial showed that high-risk patients with pT3-4N0 esophageal cancer had better OS following upfront esophagectomy followed by radiotherapy therapy. This discovery may have major significance in the use of adjuvant radiotherapy following upfront esophagectomy in patients with pN0 esophageal cancer.

A Recurrence Predictive Model for Node-negative Esophageal Squamous Cell Carcinoma After Upfront Esophagectomy

The prognosis for pathologically node-negative (pN0) esophageal squamous cell carcinoma (ESCC) with surgery alone remains poor. We aimed to develop a model for a more precise prediction of recurrence, which will allow personalized management for pN0 ESCC after upfront complete resection. Clinical and pathological records of patients with completely resected pT1-3N0M0 ESCC were retrospectively analyzed between January 2014 and December 2019. A nomogram for the prediction of recurrence was established based on the Cox regression analysis and evaluated by C-index, AUC, and calibration curves. The model was further validated using bootstrap resampling and k-fold cross-validation and compared with the 8th edition of the AJCC TNM staging system using Td-ROC, NRI, IDI, and DCA. Two-hundred-and seventy cases were included in this study. The median follow-up was 45 months. Distant and/or loco-regional recurrences were noted in 89 (33.0%) patients. The predictive model revealed pT-category, differentiation, perineural invasion, examined lymph nodes (ELN), and prognostic nutritional index (PNI) as independent risk factors for recurrence, with a c-index of 0.725 in the bootstrapping cohort. Td-ROC, NRI, and IDI showed a better predictive ability than the AJCC 8th TNM staging system. Based on this model, patients in the low-risk group had a significantly lower recurrence incidence than those in the high-risk group (p < .001). The predictive model developed in this study may facilitate the precise prediction of recurrences for pN0 ESCC after upfront surgery. Stratifying management of those patients might bring significantly better survival benefits.

Lymphatic invasion is a prognostic factor of pathological N0 esophageal squamous cell carcinoma

Adjuvant treatment after upfront esophagectomy for esophageal squamous cell carcinoma (ESCC) is indicated only for patients with lymph node metastasis in Japan. However, the recurrence rate after curative resection is high even for node-negative patients; thus, understanding the prognostic factors for patients with node-negative ESCC, which still remains unidentified, is important. Here, we aimed to reveal the prognostic factors for the long-term outcomes of patients with node-negative ESCC. Moreover, we compared the long-term outcomes among high-risk node-negative and node-positive patients. This single-institution retrospective study included 103 patients with pT1b-3N0 ESCC who underwent upfront surgery to identify the population at a high risk of recurrence. To compare overall survival (OS) and recurrence-free survival (RFS) between high-risk node-negative and node-positive patients, 51 node-positive ESCC patients with pStage IIIA or less who had undergone upfront surgery were also included. Univariable and multivariable analyses were performed using the Cox proportional hazard regression model. OS and RFS were compared using the log-rank test. Only lymphatic invasion (Ly+) was associated with worse 3-year OS (hazard ratio, 8.63; 95% confidence interval, 2.09-35.69; P = 0.0029) and RFS (hazard ratio, 4.87; 95% confidence interval, 1.69-14.02; P = 0.0034). The node-negative and Ly+ patients showed significantly worse OS (P = 0.0242) and RFS (P = 0.0114) than the node-positive patients who underwent chemotherapy. Ly+ is the only independent prognostic factor in patients with node-negative ESCC. Patients with node-negative and Ly+ ESCC may benefit from adjuvant treatment.

Postoperative survival effect of the number of examined lymph nodes on esophageal squamous cell carcinoma with pathological stage T1-3N0M0

BACKGROUND

The postoperative survival effect of the number of examined lymph nodes on patients of R0-resected esophageal squamous cell carcinoma with pathological stage T1-3N0M0 is still unclear.

METHODS

Patients diagnosed with pathological stage T1-3N0M0 esophageal squamous cell carcinoma from two cancer databases-our cancer center (N = 707), and Surveillance Epidemiology and End Results (N = 151). The primary clinical endpoint was overall survival. The X-tile software was used to determine the optimal cutoff value of the number of examined lymph nodes, and propensity score matching was conducted to reduce selection bias according to the results of X-tile software. The cohort of 151 patients from another database was used for validation.

RESULTS

X-tile software provided an optimal cutoff value of 15 examined lymph nodes based on 707 patients, and 231 pairs of matched patients were included. In the unmatched cohort, Cox proportional hazard regression analysis revealed better overall survival in patients with more than 15 examined lymph nodes (adjusted hazard ratio, 0.566, 95% confidence interval, 0.445-0.720; p < 0.001) compared with patients with 15 or fewer examined lymph nodes. In the validation cohort, patients with more than 15 examined lymph nodes also had better overall survival (adjusted hazard ratio 0.665, p = 0.047).

CONCLUSIONS

The number of examined lymph nodes is a significant prognostic factor in esophageal squamous cell carcinoma patients with pathological stage T1-3N0M0, and more than 15 examined lymph nodes are associated with better overall survival. Although the difference is not significant, the survival curve of patients with examined lymph nodes > 30 is better than those with examined lymph nodes 15-30. We believe that the number of examined lymph nodes can provide prognostic guidance for those patients, and the more examined lymph nodes cause lesser occult lymph nodes metastasis and lead to a better prognosis. Therefore, surgeons and pathologists should try to examine as many lymph nodes as possible to evaluate the pathological stage precisely. However, we need more validation from other studies.

Examined lymph node count is not associated with prognosis in elderly patients with pN0 thoracic esophageal cancer

The purpose of this study was to determine whether the number of lymph nodes dissected predicts prognosis in surgically treated elderly patients with pN0 thoracic esophageal cancer. We searched the Surveillance, Epidemiology, and End Results database and identified the records of younger (<75 years) and older (≥75 years) patients with pN0 thoracic esophageal cancer between 1998 and 2015. The patient characteristics, tumor data, and postoperative variables were analyzed in this study. The Kaplan-Meier method and a Cox proportional hazard model were used to compare overall and cause-specific survival. Data from 1,792 esophageal cancer patients (older: n = 295; younger: n = 1497) were included. The survival analysis showed that the overall and cause-specific survival in the patients with ≥15 examined lymph nodes (eLNs) was significantly superior to that in the patients with 1 to 14 eLNs (P < .001); however, the difference disappeared in the older patients. After stratification by the tumor location, histology, pT classification, and differentiation between the younger and older cohorts to analyze the association between eLNs and survival, we found that the differences remained significant in most subgroups in the younger cohort. There were no differences in any subgroups of older patients. This study replicated the previously identified finding that long-term survival in patients with extensive lymphadenectomy was significantly superior to that in patients with less extensive lymphadenectomy. However, less extensive lymphadenectomy may be an acceptable treatment modality for elderly patients with pN0 thoracic esophageal cancer.

Prognostic impact of examined lymph node count in pT1N0M0 esophageal cancer: A population-based study

Background

Research on the impact of examined lymph node (ELN) count on node‐negative esophageal cancer (EC) especially pT1N0M0 EC is inadequate. This study was designed to analyze the prognostic impact of ELN count on pT1N0M0 EC.

Methods

Data of resected pT1N0M0 EC patients between 1988 and 2015 were extracted from the United States Surveillance, Epidemiology, and End Results (SEER) database. The association between ELN count and overall survival (OS) or esophageal cancer‐specific survival (ECSS) were investigated. Factors that may predict the outcome were identified using the Kaplan‐Meier method and the Cox proportional‐hazards model.

Results

A total of 906 patients who underwent resection with at least one lymph node (LN) retrieved met our criteria. The cumulative 5‐year OS was 67.6%, while the cumulative 5‐year ECSS was 75.4%. X‐Tile analysis showed that 12 was the optimal cutoff value for ELN count in terms of both OS (χ2 = 28.764, P < 0.0001) and ECSS (χ2 = 15.668, P = 0.0026). A Kaplan‐Meier survival analysis and log‐rank comparison revealed that ELN > 12 was significantly associated with better OS (HR, 0.532; 95% CI, 0.421–0.672; P < 0.001) and ECSS (HR, 0.561; 95% CI, 0.420–0.749; P < 0.001) rates than ELN ≤12. The OS and ECSS benefit of increasing ELN count were also reflected in the multivariate analysis after adjustment for age, sex, race, marital status, location, T stage, tumor size, pathology, and differentiation.

Conclusions

These findings indicated that greater number of ELN count exhibits prognostic significance in pT1N0M0 EC. We recommend more than 12 LNs should be examined in pT1N0M0 EC.

Pathologically examining a minimum of three lymph nodes could better determine node negativity in patients with non-metastatic chromophobe renal cell carcinoma

Objective

To evaluate the prognostic value of lymph node (LN) involvement for patients with chromophobe renal cell carcinoma (chRCC) and ascertain the minimum number of LNs that need to be pathologically examined to reliably diagnose a patient with node negative chRCC.

Methods

From 2004 to 2014, non-metastatic chRCC patients receiving radical nephrectomy together with lymphadenectomy were identified from the Surveillance, Epidemiology and End Results (SEER) database. The primary outcome was overall survival (OS).

Results

Two hundred and forty-six patients received lymph node dissection during the surgery. Of the patients, 24 (10%) had pathologically confirmed positive LN. Multivariate Cox regression model showed that positive LN was an independent unfavorable predictor for OS (HR = 2.83, 95%CI = 1.14-6.98, P = 0.024). More importantly, LN(-) patients with at least three LNs dissected had significantly better OS compared with when 1-2 LNs were examined (P = 0.048). Multivariate analysis confirmed that in LN(-) patients, the examination of three or more LNs could independently predict better OS compared with patients with only 1-2 LNs dissected (HR≥3LNs = 0.362, 95% CI = 0.135-0.972, P = 0.044). Additionally, the likelihood of finding at least one positive LN was significantly higher on dissection of ≥3 LNs compared with examination of 1-2 LNs (15% vs 5%, P = 0.018). Decision curve analysis found a better clinical validity of the '3 LNs examined'-based classification compared with the traditional LN(-)/LN(+) classification.

Conclusion

The proportion of positive LNs in chRCC was far from neglectable and LN metastasis could independently predict unfavorable OS. We recommended a minimum of three LNs should be pathologically examined in order to reliably determine node negative.