Refining the Nodal Staging for Esophageal Squamous Cell Carcinoma Based on Lymph Node Stations

Synchronous carcinomas of the esophagus: Influence of prognosis and staging

OBJECTIVE

Synchronous carcinomas of the esophagus (SCEs), occurring at multiple locations in the esophagus or the esophagogastric junction, are uncommon. In this study, we retrospectively analyzed patients with SCEs, focusing on the types of SCEs and their influence on staging and prognosis.

METHODS

Data of patients treated surgically for esophageal carcinoma between January 2009 and January 2016 were retrieved from the database in the thoracic surgery department of our hospital. The clinicopathologic features of SCEs were collected. The factors on TNM staging and prognosis of SCEs were also analyzed.

RESULTS

A total of 103 patients (2.8 %) with SCEs were found among 3662 consecutive patients. Based on the features of multiple carcinomas, 13 patients (0.35 %) exhibited intramural skip metastasis and 90 patients (2.46 %) displayed multiple primary carcinomas (MPCs). Patients with single esophageal cancer were propensity-matched at a ratio of 1:2 as control group. Among the patients with MPCs, tumor B was defined as the relatively early or superficial lesion. The 5-year OS of patients with MPCs with Tumor B (T1b/2) vs. matched group was 35.0 % vs. 48.45 % respectively (P = 0.013). For the N-stage of SCEs, a revised N-staging system, based on the number of involved lymph node stations better separated sub-N-stage survival curves (P = 0.002), compared with the conventional system (P = 0.019).

CONCLUSIONS

For the pT-stage evaluation of MPCs, the second tumor should be taken into consideration. The revised N-staging system could better reflect the lymph node metastatic characteristics and predict survival in SCEs.

Development and validation of a predictive model for overall survival in esophageal squamous cell carcinoma post-esophagectomy: the role of lymph node metastatic stations

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) poses a substantial healthcare challenge, particularly in areas such as East Asia. The pathologic nodal (pN) stage of ESCC remains a controversial factor. Accurately predicting overall survival (OS) after esophagectomy is crucial for treatment planning and improving treatment outcomes.

METHOD

An analysis was conducted using data from Esophageal Cancer Case Management Database of Sichuan Cancer Hospital and Institute, spanning from January 2010 to December 2017. Our study aimed to examine the clinicopathological characteristics, lymph node resection at individual stations, and treatment details of patients with ESCC who underwent esophagectomy. In addition, a novel nodal stage (N stage) was based on the number of lymph node metastasis (LNM) stations, and a prediction model for OS was devised using the pN stage and the newly proposed N stage.

RESULTS

After analyzing 49 indicators through univariate and multifactorial analyses, 25 of the most significant factors affecting OS after esophagectomy were identified. Further analysis using least absolute shrinkage and selection operator regression revealed six key factors. Models were developed based on the pN stage and the newly introduced N stage. Evaluation of the area under the curve indicated that Model 2 exhibited slightly superior clinical utility compared to Model 1.

CONCLUSIONS

Our study demonstrates that the newly introduced N stage, based on the number of LNM stations, exhibits comparable performance to the current American Joint Committee on Cancer/Union for International Cancer Control pN system, with a slight advantageous edge.

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.

Increased resected lymph node stations improved survival of esophageal squamous cell carcinoma

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) and surgery have been recommended as the standard treatments for locally advanced esophageal squamous cell carcinoma (ESCC). In addition, nodal metastases decreased in frequency and changed in distribution after neoadjuvant therapy. This study aimed to examine the optimal strategy for lymph node dissection (LND) in patients with ESCC who underwent nCRT.

METHODS

The hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) were calculated using the Cox proportional hazard model. To determine the minimal number of LNDs (n-LNS) or least station of LNDs (e-LNS), the Chow test was used.

RESULTS

In total, 333 patients were included. The estimated cut-off values for e-LNS and n-LNS were 9 and 15, respectively. A higher number of e-LNS was significantly associated with improved OS (HR: 0.90; 95% CI 0.84-0.97, P = 0.0075) and DFS (HR: 0.012; 95% CI: 0.84-0.98, P = 0.0074). The e-LNS was a significant prognostic factor in multivariate analyses. The local recurrence rate of 23.1% in high e-LNS is much lower than the results of low e-LNS (13.3%). Comparable morbidity was found in both the e-LNS and n-LND subgroups.

CONCLUSION

This cohort study revealed an association between the extent of LND and overall survival, suggesting the therapeutic value of extended lymphadenectomy during esophagectomy. Therefore, more lymph node stations being sampled leads to higher survival rates among patients who receive nCRT, and standard lymphadenectomy of at least 9 stations is strongly recommended.

Abdominal lymph node metastasis in non-surgical esophageal squamous cell carcinoma: prognostic significance and a novel staging strategy

Purpose

This study aimed to evaluate the feasibility of a combination of abdominal lymph node (LN) metastasis and the number of LNs in esophageal squamous cell carcinoma (ESCC) patients to optimize its clinical nodal staging.

Methods

A retrospective study, including a total of 707 ESCC patients treated with definitive radiotherapy, was conducted at two participating institutes. Different combinations of LN variables, including abdominal LN metastasis (R1: no-abdominal LN metastasis; R2: abdominal LN metastasis), were further analyzed to propose a potential revised nodal (rN) staging.

Results

The multivariate analyses showed that the number of metastatic LN and abdominal LN metastasis were independent prognostic factors for the overall survival (OS). The results showed no significant differences in the OS between the N2 patients with abdominal LN metastasis and N3 patients. The OS of the stage III patients with abdominal LN metastasis was not significantly different from those with stage IVa. The N3R1 and N1-2R2 had similar hazard ratios (HRs). The N1R1 subset was defined as rN1, the N2R1 subset was defined as rN2, and the N3R1-2 and N1-2R2 subsets were defined as rN3. The HRs of OS of the rN2 and rN3 groups increased subsequently. The rN stage could identify the differences in the OS times of each subgroup based on the 8th AJCC cN staging or the 11th JES N staging.

Conclusions

The rN staging, including the number of metastatic LNs and abdominal LN metastasis, might serve as a potential prognostic predictor for non-surgical patients with ESCC.

The prognostic value of 11th Japanese classification and 8th AJCC staging systems in Chinese patients with esophageal squamous cell carcinoma

BACKGROUND

Two staging systems, the 8th staging system by the American Joint Committee on Cancer (AJCC) and the 11th Japanese classification by Japan Esophageal Society (JES), are currently applied in the clinic for predicting the prognosis of patients with esophageal squamous cell carcinoma (ESCC). The differences between the two staging systems have been widely researched. However, little studies focus on the differences in specific staging between the two systems. Therefore, we aimed to compare the performance of different staging in predicting overall survival (OS) of Chinese patients with ESCC.

METHODS

This retrospective study included 268 patients who underwent radical esophagectomy and mediastinal lymph node dissection for ESCC between January 2008 and December 2013. Patients were staged by the 8th AJCC and 11th JES staging systems. OS was estimated using the Kaplan-Meier method and compared between N stages and between stage groupings using the log-rank test. Cox proportional hazards regression analysis was performed to identify factors independently related to outcome. Further, we compared the concordance indexes (C-indexes) of the two staging systems.

RESULTS

The mean age was 61.25 ± 7.056 years, median follow-up was 44.82 months, and 5-year OS rate was 47%. The OS was well predicted by the 8th AJCC N staging (P < 0.001) and the 11th JES N staging (P < 0.001), with a c-index of 0.638 (95% CI: 0.592-0.683) for AJCC N staging and 0.627 (95% CI: 0.583-0.670) for JES N staging (P = 0.13). In addition, the OS was also well predicted by stage groupings of the 8th AJCC (P < 0.001) and the 11th JES systems (P < 0.001), with a c-index of 0.658 (95% CI: 0.616-0.699) for 8th AJCC stage grouping and 0.629 (95% CI: 0.589-0.668) for the11th JES stage grouping (P = 0.211).

CONCLUSIONS

The prognostic effect of 11th JES staging system is comparable with that of AJCC 8th staging system for patients with ESCC. Therefore, both systems are applicable to clinical practice.

Pararespiratory and paradigestive lymph node metastases in esophageal squamous cell carcinoma: predicting survival and refining the N staging system

BACKGROUND

The site of lymph node metastasis (LNM) may affect the prognosis of patients with esophageal squamous cell carcinoma (ESCC). To investigate the prognoses of pararespiratory and paradigestive LNM and to propose a novel N (nN) staging system that integrates both the LNM site and count.

METHODS

This study was a multicenter, large-sample, retrospective cohort study that included ESCC patients with LNM between January 2014 and December 2019 from three Chinese institutes. Patients were set into training (two institutes) and external validation (one institute) cohorts. The primary outcomes were survival differences in LNM site and the development of novel nodal staging system. The overall survival (OS) of patients with pararespiratory LNM only (Group A), paradigestive LNM only (Group B), and both sites (Group C) was evaluated by Kaplan-Meier. Cox proportional hazards models were used to identify the independent prognostic factors. An nN staging system considering both the LNM site and count was developed and evaluated by the area under the receiver operating characteristic curve (AUC).

RESULTS

In total, 1313 patients were included and split into training (n = 1033) and external validation (n = 280) cohorts. There were 342 (26.0%), 568 (43.3%) and 403 (30.7%) patients in groups A, B and C, respectively. The OS of patients with pararespiratory and patients with paradigestive LNM presented significant differences in the training and validation cohorts (P < 0.050). In the training cohort, LNM site was an independent prognostic factor (hazard ratio: 1.58, 95% confidence intervals: 1.41-1.77, P < 0.001). The nN staging definition: nN1 (1-2 positive pararespiratory/paradigestive LNs), nN2 (3-6 pararespiratory LNs or 1 pararespiratory with 1paradigestive LN), nN3 (3-6 LNs with ≥ 1 paradigestive LN), nN4 (≥ 7 LNs). Subsets of patients with different nN stages showed significant differences in OS (P < 0.050). The prognostic model of the nN staging system presented higher performance in the training and validation cohorts at 3-year OS (AUC, 0.725 and 0.751, respectively) and 5-year OS (AUC, 0.740 and 0.793, respectively) than the current N staging systems.

CONCLUSIONS

Compared to pararespiratory LNM, the presence of paradigestive LNM is associated with worse OS. The nN staging system revealed superior prognostic ability than current N staging systems.

Lymph node metastasis is not associated with survival in patients with clinical stage T4 esophageal squamous cell carcinoma undergoing definitive radiotherapy or chemoradiotherapy

Background

Clinical T4 stage (cT4) esophageal tumors are difficult to be surgically resected, and definitive radiotherapy (RT) or chemoradiotherapy (dCRT) remains the main treatment. The study aims to analyze the association between the status of lymph node (LN) metastasis and survival outcomes in the cT4 stage esophageal squamous cell carcinoma (ESCC) patients that underwent treatment with dCRT or RT.

Methods

This retrospective study analyzed the clinical data of 555 ESCC patients treated with dCRT or RT at the Shandong Cancer Hospital and the Liaocheng People’s Hospital from 2010 to 2017. Kaplan–Meier and Cox regression analyses was performed to determine the relationship between LN metastasis and survival outcomes of cT4 and non-cT4 ESCC patients. The chi-square test was used to evaluate the differences in the local and distal recurrence patterns in the ESCC patients belonging to various clinical T stages.

Results

The 3-year survival rates for patients with non-cT4 ESCC and cT4 ESCC were 47.9% and 30.8%, respectively. The overall survival (OS) and progression-free survival (PFS) rates were strongly associated with the status of LN metastasis in the entire cohort (all P &lt; 0.001) and the non-cT4 group (all P &lt; 0.001) but not in the cT4 group. The local recurrence rates were 60.7% for the cT4 ESCC patients and 45.1% for the non-cT4 ESCC patients (P &lt; 0.001). Multivariate analysis showed that clinical N stage (P = 0.002), LN size (P = 0.007), and abdominal LN involvement (P = 0.011) were independent predictors of favorable OS in the non-cT4 group. However, clinical N stage (P = 0.824), LN size (P = 0.383), and abdominal LN involvement (P = 0.337) did not show any significant correlation with OS in the cT4 ESCC patients.

Conclusions

Our data demonstrated that the status of LN metastasis did not correlate with OS in the cT4 ESCC patients that received dCRT or RT. Furthermore, the prevalence of local recurrence was higher in the cT4 ESCC patients.

Patterns and Impact of Nodal Metastases After Neoadjuvant Chemoradiation and R0 Resection in Esophageal Adenocarcinoma

OBJECTIVE

Little is known about the pattern of nodal metastases in patients with esophageal adenocarcinoma who have received neoadjuvant chemoradiation and undergone surgery. We sought to assess this pattern and evaluate its association with prognosis.

METHODS

All patients with esophageal adenocarcinoma who underwent neoadjuvant chemoradiation and R0 esophagectomy between 2010 and 2018 at our institution were included (n = 537). The primary objective was to evaluate the association of sites of lymph node metastases with disease-free survival. The number of nodal stations and individual sites of nodal metastases were evaluated first in univariable then in separate multivariable Cox regression models adjusted for clinical factors.

RESULTS

Of 537 patients, 193 (36%) had pathologic nodal metastases at the time of surgery; 153 (28%) had single-station disease, 32 (6.0%) had 2-station disease, and 8 (1.5%) had 3-station disease. The majority of patients with multiple positive nodal stations had positive nodes in the paraesophageal (93%) and/or left gastric stations (60%). Multivariable models controlling for clinical factors showed that an increasing number of positive nodal stations (hazard ratio, 1.59; 95% CI, 1.35-1.84; P < .01)-in particular, the subcarinal (hazard ratio, 2.78; 95% CI, 1.54-5.03; P < .01) and paraesophageal stations (hazard ratio, 2.0; 95% CI, 1.58-2.54; P < .01)-was associated with increased risk of recurrence.

CONCLUSIONS

One-third of patients who have undergone R0 resection for esophageal adenocarcinoma following induction chemoradiation therapy have metastatic lymph nodes. An increasing number of nodal stations, particularly paraesophageal and subcarinal metastases, were associated with increased risk of recurrence.

The impact of the nodal status on the overall survival of non-surgical patients with esophageal squamous cell carcinoma

BACKGROUND

The prognosis of N categories for patients with non-surgical esophageal carcinoma based on the number of metastatic lymph nodes is controversial. The present study analyzes prognostic implications of the number, extent, and size of metastatic lymph nodes for patients with esophageal squamous cell carcinoma (ESCC) treated with definitive (chemo-)radiotherapy to provide more information on treatment strategy.

METHODS

We reviewed 357 ESCC patients treated with definitive radiotherapy between January 2013 and March 2016 retrospectively. We assessed potential associations between the involved extent (N0, 1 region, 2 regions, and 3 regions), number (N0, 1-2, 3-6, and ≥ 7), and size (N0, ≤2 cm, and > 2 cm) of metastatic lymph nodes and overall survival. Multivariate analyses of the clinicopathological factors were performed using the Cox proportional hazard model.

RESULTS

5-year survival rates were 43.6% for patients in the N0 group and 29.3% in the N+ group (p = 0.001). Kaplan-Meier analyses for all cases revealed that there were significant differences in survival based on the extent (the OS rates at 3 years were 53.3% for patients in the N0 group, 45.7% in the 1 region-involved group, 28.0% in the 2 regions-involved group, and 13.3% in the 3 regions-involved group, P < 0.001), number (the OS rates at 3 years were 49.0% for patients in the 1-2 LNs group, 27.8% in the 3-6 LNs group, 0 in the ≥7LNs group, P < 0.001), and size (the OS rates at 3 years were 41.6% for patients in the LNs ≤2 cm group and 20.7% in the LNs > 2 cm group, P = 0.001) of metastatic LNs. One hundred seventy-two patients (48.2%) had experienced GTV failure, 157 (43.1%) had distant failure, 49 (13.7%) had out-of-GTV nodal failure, and 70 patients (19.6%) had no evidence of disease at the last follow-up. Nodal status correlated statistically with GTV failure. Patients with LN metastases in the abdominal region had worse survival rates than those with metastases in the other regions. The extent and number of metastatic LNs, T category, Primary tumor location, and chemotherapy were independent prognostic factors of OS in multivariate analyses.

CONCLUSIONS

For patients with ESCC who received definitive (chemo-)radiotherapy, the number, extent, and size of metastatic LNs were prognostic factors, particularly of the T2/3 disease. Patients with LN metastases in the abdominal region had worse survival.

Nimotuzumab Plus Paclitaxel and Cisplatin as a 1st-Line Treatment for Esophageal Cancer: Long Term Follow-up of a Phase II Study

The effect of anti-epidermal growth factor receptor targeted treatment in esophageal squamous cell carcinoma (ESCC) is still unclear. We conducted a prospective phase II study of paclitaxel, cisplatin, and nimotuzumab (TPN) as a first-line treatment for unresectable or metastatic ESCC and the objective response rate was 51.8%. Here, we report the long-term follow-up results of the initial trial. Fifty-nine patients were enrolled from Mar 2011 to Apr 2013 and were treated with the TPN regimen. Palliative sequential radiotherapy was given if all tumor lesions were confined to 1-2 radiation fields. Fifty-six patients were eligible for evaluation. After a median follow-up of 32.2months, the median progression-free survival (PFS) and the overall survival (OS) time were 18.1±4.2 months (95% CI: 9.8-26.4) and 26.2±10.0 months (95% CI: 6.6-45.8), respectively, in 29 patients with unresectable local-regional disease, while they were 6.6±0.4 months (95% CI: 5.8-7.5) and 11.5±3.7 months (95% CI: 4.2-18.8), respectively, in 27 patients with metastatic disease. Patients who were male, those with multiple station lymph node metastases, those with visceral metastasis, those who did not response to TPN treatment, and those who did not receive radiotherapy, had a worse OS. In 6 patients with multiple station lymph node metastasis and in 3 patients with recurrent disease and oligo-metastasis (local lymph nodes), TPN with sequential radiation resulted in a mean OS of 17.67±9.50 months and a mean OS of over 40 months, respectively. In conclusion, TPN is effective as a first-line treatment for patients with unresectable and metastatic ESCC. In addition, TPN treatment with sequential radiation might improve survival in patients with limited or oligo lymph node metastases.

Histone deacetylase 6 expression in metastatic lymph nodes is a valuable prognostic marker for resected node-positive esophageal squamous cell cancer

Background

Histone deacetylase 6 (HDAC6) exerts enzymatic deacetylation activity on histones and on non-histone substrates and plays a key role in microtubule dynamics and chaperone activities. In addition, previous studies have demonstrated its role in cancer progression. However, its clinical significance in esophageal squamous cell cancer (ESCC) has not been elucidated. We investigated the correlation of HDAC6 expression and clinical outcome in a group of T3N1–3M0 surgically resected ESCCs.

Methods

Tissue microarrays were conducted on 209 surgically resected T3N1–3M0 ESCC tumors, including 163 pairs of primary tumors (PTs) and their corresponding metastatic lymph nodes (MLNs). Immunohistochemistry was utilized to evaluate HDAC6 protein levels. The relationship between patient outcomes and HDAC6 expression was analyzed statistically.

Results

The level of HDAC6 expression in ESCC MLNs was found to be significantly lower than that in PTs (P<0.001). Patients with lower MLN HDAC6 expression demonstrated improved overall survival (P=0.011) and disease-free survival (P=0.012) than those with higher HDAC6 expression. HDAC6 expression levels in PTs revealed no prognostic significance. Multivariate analysis showed that the MLN HDAC6 expression level was an independent prognostic factor for both overall survival (HR 1.456, P=0.029) and disease-free survival (HR 1.432, P=0.033).

Conclusion

High expression of HDAC6 in MLNs but not in PTs suggests a poor prognosis for patients with resected T3N1–3M0 ESCC. We should take into account the protein expression of MLNs when assessing prognosis in patients with lymph-node involvement.

Validity of upfront surgery for patients with unsuspected lymph node metastasis in esophageal cancer: a propensity scoring matching study

Background

Although neoadjuvant therapy followed by esophagectomy is well-established as being superior to upfront esophagectomy when locoregional lymph node (LN) metastasis is present in esophageal cancer, upfront esophagectomy without neoadjuvant therapy may be performed in patients with LN metastasis due to unreliable preoperative evaluations. However, outcomes in this setting remain unclear. The purpose of the present study was to clarify whether upfront esophagectomy without neoadjuvant therapy in patients with unsuspected lymph node metastasis in esophageal cancer is appropriate.

Methods

We included 215 squamous cell esophageal cancer patients who met the study criteria. Inclusion criteria included complete (R0) and curative surgery cases, intra-thoracic esophageal cancer, preoperative biopsy-proven squamous cell carcinoma, and cases without LN metastasis (WL, cN0 and pN0) or with unsuspected LN metastasis (UL, cN0 and pN1). Exclusion criteria were palliation or salvage cases, other uncured previous or current primary cancers, complete remission cases, and operative mortalities (defined as patients who died during hospitalization or within one month after surgery). We compared 5-year disease- free survival (DFS) between WL and UL. In addition, we investigated the influence of neoadjuvant therapy in UL. To overcome heterogeneity in baseline characteristics between the groups, a propensity matched-analysis based on propensity scores was then carried out to create a cohort of WL with clinical characteristics similar to those in UL.

Results

The incidence of UL among preoperative N0 patients was 25.6% and the incidence of UL cases who did not receive neoadjuvant therapy was 47.2%. All subjects were stratified into either WL (160 patients) or UL (55 patients). Twenty nine of 55 patients in UL received neoadjuvant therapy before esophagectomy and all patients with LN metastasis received adjuvant therapy after esophagectomy. There was no significant difference in DFS between WL and UL (p = 0.242). Furthermore, there were no significant differences in DFS between cases that received and did not receive neoadjuvant therapy (p = 0.769).

Conclusions

Upfront surgery without neoadjuvant therapy in UL is appropriate for patients who can tolerate adjuvant therapy.

A new classification of lymph node metastases according to the lymph node stations for predicting prognosis in surgical patients with esophageal squamous cell carcinoma

Lymph node metastasis (LNM) is one of the major prognostic factors for esophageal squamous cell carcinoma (ESCC). However there is no consensus regarding the prognostic significance of the location of LNM. Therefore, a novel classification was proposed to identify the lymph node (LN) stations which may be useful in predicting prognosis. A total of 260 ESCC patients were enrolled in this prospective study. The prognostic values of LNM in different lymph node (LN) stations were evaluated by random survival forests (RSF). Their prognostic significance was examined by Cox regression and receiver operating characteristic curve (ROC). The three most frequently involved LN stations were station 16 (24.49%), station 1 (22.22%) and station 2 (21.05%). Stations 1, 2, 8M, 8L and 16 were grouped as dominant LN stations (DLNS) which showed higher values in predicting overall survival (OS) and disease-free survival (DFS) than the remaining LN stations, which we define as non-dominant LN stations (N-DLNS). LNM features of DLNS (number of positive LN stations, number of positive LNs and LN ratio), but not those from N-DLNS, served as independent prognostic factors (P<0.05) whenever used alone or when combined with factors from N-DLNS. Furthermore, the area under ROC indicated that DLNS is a more accurate prediction than N-DLNS (P<0.05). This study demonstrated the value of LNM in DLNS in predicting prognosis in surgical ESCC patients, which outperformed those from N-DLNS. Therefore, the method of dominant and non-dominant classification may serve as an additional parameter to improve individualized therapeutic strategies.

Strategies of nodal staging of the TNM system for esophageal cancer

The 8^th edition of UICC/AJCC TNM staging for esophageal cancer will start in use since 2018. The nodal staging in this version of TNM system remains unchanged from the 7^th edition that based on the number of lymph nodes (LN) involved, except the limited revision of the regional LN map. In this review, N staging revision was evaluated from its initially simple definition of negative (N0) and positive (N1) LN(s) to the current positive node number based proposal. Meanwhile the disadvantages of current N staging were discussed. The refined nodal staging system in view of the number of metastatic node stations was introduced; as well as the extent and station of metastatic node could better reflect the disease progression and prognosis. The controversy on N staging of esophagogastric junction cancer was also discussed. Other reported N staging associated elements including LN ratio and lymphatic vessel invasion were reviewed and evaluated.

Numeric pathologic lymph node classification shows prognostic superiority to topographic pN classification in esophageal squamous cell carcinoma

BACKGROUND

The current eighth tumor node metastasis lymph node category pathologic lymph node staging system for esophageal squamous cell carcinoma is based solely on the number of metastatic nodes and does not consider anatomic distribution. We aimed to assess the prognostic capability of the eighth tumor node metastasis pathologic lymph node staging system (numeric-based) compared with the 11th Japan Esophageal Society (topography-based) pathologic lymph node staging system in patients with esophageal squamous cell carcinoma.

METHODS

We retrospectively reviewed the clinical records of 289 patients with esophageal squamous cell carcinoma who underwent esophagectomy with extended lymph node dissection during the period from January 2006 through June 2016. We compared discrimination abilities for overall survival, recurrence-free survival, and cancer-specific survival between these 2 staging systems using C-statistics.

RESULTS

The median number of dissected and metastatic nodes was 61 (25% to 75% quartile range, 45 to 79) and 1 (25% to 75% quartile range, 0 to 3), respectively. The eighth tumor node metastasis pathologic lymph node staging system had a greater ability to accurately determine overall survival (C-statistics: tumor node metastasis classification, 0.69, 95% confidence interval, 0.62-0.76; Japan Esophageal Society classification; 0.65, 95% confidence interval, 0.58-0.71; P = .014) and cancer-specific survival (C-statistics: tumor node metastasis classification, 0.78, 95% confidence interval, 0.70-0.87; Japan Esophageal Society classification; 0.72, 95% confidence interval, 0.64-0.80; P = .018). Rates of total recurrence rose as the eighth tumor node metastasis pathologic lymph node stage increased, while stratification of patients according to the topography-based node classification system was not feasible.

CONCLUSION

Numeric nodal staging is an essential tool for stratifying the oncologic outcomes of patients with esophageal squamous cell carcinoma even in the cohort in which adequate numbers of lymph nodes were harvested.

Adequate lymphadenectomy in patients with oesophageal squamous cell carcinoma: resecting the minimal number of lymph node stations

OBJECTIVES

The seventh edition of the American Joint Committee on Cancer (AJCC) tumour-node-metastasis (TNM) staging system for oesophageal cancer did not define the minimal requirement for an adequate extent of lymphadenectomy in patients with oesophageal cancer. This study aimed to define the minimum number of lymph node (LN) stations to be resected in patients with oesophageal squamous cell carcinoma (OSCC).

METHODS

We conducted a retrospective review of clinicopathological data from 2033 patients with OSCC undergoing complete resection between August 2005 and September 2013. An ordinal logistic regression analysis was used to identify the variables associated with revised N (rN) staging progression and indices that could be used in the stratified analysis. To determine the optimal number of resected LN stations, we compared the overall survival hazard ratio between groups with different numbers of LN stations using a Cox's proportional hazards regression model. The highest χ(2) value was deemed the cut-off point.

RESULTS

The progression of rN staging was influenced by T-staging, G-staging, tumour length (>3 cm), lymphovascular invasion and number of resected LN stations. According to Cox's proportional hazards regression model, we recommended that at least six LN stations should be removed. Then, we conducted a stratified analysis by G status and tumour length. We found that at least seven LN stations should be removed in patients with G3 or tumour length >3 cm.

CONCLUSIONS

For thoracic OSCC, at least six LN stations had to be removed. Furthermore, for patients with G3 or tumour length >3 cm, the recommendation was seven.