Prognostic significance of solitary lymph node metastasis in patients with squamous cell carcinoma of middle thoracic esophagus

Prognostic value of node skip metastasis on esophageal cancer: A systematic review and meta-analysis

The association between NSM and prognosis of esophageal cancer remains controversial, though several studies have been conducted drawing their own conclusion. Therefore, we firstly carried out this meta-analysis aiming to explore the association. We performed a comprehensive literature search online, including PubMed, Embase and Web of Science. We selected deaths at 5 years and hazard ratio (HR) with 95% (CI) to perform the meta-analysis with Review Manager 5.3, predicting value of clinic-pathological features in NSM also been analyzed. A total of 7 studies were finally enrolled in this study. NSM, defined by either JSED criterion or anatomical compartment criterion, neither showed significant prognostic value on OS of esophageal cancer (P = 0.64), (P = 0.24). Subgroup analysis of JSED criterion, NSM was not a prognostic factor in solitary node metastasis patients (P = 0.39), whereas NSM demonstrated a poor prognostic factor (P = 0.01) for ESCC. Subgroup analysis according to anatomical criterion, NSM was a favorable factor for OS in middle thoracic ESCC (P = 0.003). Pathological N1 status was found to be a risk factor for NSM (P < 0.00001) according to JSED criterion and middle thoracic ESCC was identified as a predictor for NSM (P = 0.0003) according to anatomical compartment criterion. According to JSED criterion, NSM demonstrated poor prognosis on ESCC and N1 status was a risk factor for NSM. Concerning the anatomical compartment criterion, a favorable prognosis of NSM was found in middle thoracic ESCC and NSM was prone to occur in middle thoracic ESCC. CRD42021219333.

Role of nodal skip metastasis in patients with mid-thoracic oesophageal squamous cell carcinoma: a propensity score matching study

OBJECTIVES

Nodal skip metastasis (NSM) is a common phenomenon in mid-thoracic oesophageal squamous cell carcinoma (MT-OSCC); however, the prognostic implications of NSM in patients with MT-OSCC remain unclear.

METHODS

This retrospective study enrolled 300 patients with MT-OSCC who underwent radical oesophagectomy and who had pathologically confirmed lymph node metastasis from January 2014 to December 2016. The patients were divided into 2 groups according to the presence or absence of NSM. Propensity score matching was applied to minimize patient selection bias. The impact of NSM on overall survival (OS) was assessed by Kaplan-Meier and multiple Cox proportional hazards analyses. The median follow-up time was 57 months.

RESULTS

The NSM rate in the entire cohort was 22.0% (66/300). Pathological N (pN) stage (P < 0.001) and sex (P = 0.001) were identified as significant independent risk factors for NSM. NSM was more frequent in pN1 compared with pN2 patients (87.9% vs 12.1%, P < 0.001) and no NSM was found in pN3. NSM(+) patients had better prognoses than NSM(-) patients (Kaplan-Meier; 3-year OS, 62.1% vs 34.1%, P < 0.001). Propensity score matching produced 51 matched pairs, and the 3-year OS was still better in the NSM(+) compared with the NSM(-) group (66.7% vs 40.0%, P = 0.025). Multivariable Cox analysis confirmed NSM(+) as an independent factor favouring OS in patients with MT-OSCC.

CONCLUSIONS

NSM usually occurs at pN1 stage in patients with MT-OSCC, and is associated with a favourable prognosis.

Prognostic Role of Nodal Skip Metastasis in Thoracic Esophageal Squamous Cell Carcinoma: A Large-Scale Multicenter Study

BACKGROUND

Nodal-skip metastasis (NSM) is found in esophageal squamous cell carcinoma (ESCC), but its prognostic role is controversial. This study aimed to investigate the prognostic value of NSM for thoracic ESCC patients.

METHODS

Categorization of NSM was according to the N groupings of Japan Esophagus Society (JES) staging system, which is dependent on tumor location. Using the Kaplan-Meier method and Cox-regression analysis, this study retrospectively analyzed the overall survival (OS) for 2325 ESCC patients after radical esophagectomy at three high-volume esophageal cancer centers. Predictive models also were constructed.

RESULTS

The overall NSM rate was 20% (229/1141): 37.4% in the in upper, 12.9% in the middle, and 22.2% in the lower thoracic ESCC. The patients with NSM always had a better prognosis than those without NSM. Furthermore, NSM was an independent prognostic factor for thoracic ESCC patients (hazard ratio [HR], 0.633; 95% confidence interval [CI], 0.499-0.803; P < 0.001). By integrating the prognostic values of NSM and N stage, the authors proposed the new N staging system. The categories defined by the new N staging system were more homogeneous in terms of OS than those defined by the current N system. Moreover, the new N system was shown to be an independent prognostic factor also for thoracic ESCC patients (HR, 1.607; 95% CI, 1.520-1.700; P < 0.001). Overall, the new N system had slightly better homogeneity, discriminatory ability, and monotonicity of gradient than the current N system.

CONCLUSIONS

This study emphasized the prognostic power of NSM and developed a modified node-staging system to improve the efficiency of the current International Union for Cancer Control (UICC)/American Joint Committee on Cancer (AJCC) N staging system.

Elucidation of the Anatomical Mechanism of Nodal Skip Metastasis in Superficial Thoracic Esophageal Squamous Cell Carcinoma

Background

Lymph node metastasis (LNM) is a standard mechanism of cancer progression in esophageal squamous cell carcinoma (ESCC). We aimed to clarify the anatomical mechanism of skip nodal metastasis to mediastinal zones by analyzing the relationship between LNM to sentinel zones and lymphatic vessel counts in the muscle layer adjacent to the outer esophagus.

Methods

We examined the surgical records of 287 patients with ESCC who underwent potentially curative surgery (three-field lymphadenectomy) and whole esophagi, including pharynges and stomachs from 10 cadavers, to determine the number of lymphatic vessels in the intra-outer longitudinal muscle layer adjacent to the outer esophagus of the cervical (Ce), upper thoracic, middle thoracic (Mt), lower thoracic (Lt), and abdominal esophagi (Ae).

Results

The frequency of LNM to the middle mediastinal and supraclavicular zones, including the Mt and Ce, respectively, was lower than to the upper and lower mediastinal and abdominal zone in patients with superficial and advanced thoracic ESCC. In cadavers, the lymphatic vessel counts of the intra-outer longitudinal muscle layer in the Mt and Ce were significantly lower than those of the Lt and Ae, suggesting that lymphatic flow toward the outside of the Mt and Ce was not more abundant than to other sites.

Conclusion

Our anatomical data suggested that the absence of intra-muscle lymphatic vessels in the middle mediastinal and supraclavicular zones causes skip LNM in patients with thoracic ESCC. Thus, standard esophagectomy with lymph node dissection, including distant zones, may be appropriate for treating patients with superficial thoracic ESCC.

Electronic supplementary material

The online version of this article (10.1245/s10434-018-6390-0) contains supplementary material, which is available to authorized users.

The extent of lymphadenectomy in esophageal resection for cancer should be standardized

The incidence of esophageal cancer increases, with approximately 482,000 patients diagnosed with esophageal cancer each year. Despite the growing incidence of esophageal carcinoma, the extent of the lymphadenectomy is still under discussion. Lymph node status is an important prognostic parameter in esophageal cancer and an independent predictor of survival. Surgical strategy depends on the distribution pattern of nodal metastases but consensus on the extent of lymphadenectomy differs worldwide. For squamous cell cancer, Japanese surgeons have standardized the 2- or 3-field lymphadenectomy according to the location of the tumor. For adenocarcinoma, in the Western World accounting for 85% of all esophageal cancers, the type of lymphadenectomy to perform is not clear. Moreover, the use of neoadjuvant therapy may influence the mediastinal lymph nodes and the significance of the lymphadenectomy for survival. These aspects have challenged the traditional policy concerning lymphadenectomy, at least in the Western World. Furthermore, an extensive lymphadenectomy may improve survival but, on the other hand, may cause significant more morbidity. An overview of the literature on the extent of lymphadenectomy for esophageal cancer with respect to the supposed lymph node distribution patterns for squamous cell carcinoma and adenocarcinoma, the different lymph node classification systems, the commonly used surgical techniques and outcomes, and the proposal of observational cohort study to standardize the type of lymphadenectomy according to the type of tumor, location and use of neoadjuvant therapy will be provided.

The prognostic value of nodal skip metastasis in resectable thoracic esophageal squamous cell carcinoma

Purpose

This study aimed to investigate the incidence of nodal skip metastasis (NSM) to identify the risk factors that influence NSM and to assess the prognostic value of NSM in patients with thoracic esophageal squamous cell carcinoma (ESCC).

Patients and methods

Between January 2009 and December 2013, 285 patients with ESCC with positive lymph nodes who underwent complete resection were enrolled.

Results

For the entire group, NSM occurred in 32.3% (92/285) of patients. The median survival time and 5-year survival rate in the NSM group were 28 months and 12.0%, respectively, compared with 36.3 months and 25.0%, respectively, in the non-NSM group (P=0.008). Both N stage (P=0.001) and T stage (P=0.014) were associated with the incidence of NSM. NSM (P=0.008), T stage (P=0.000), and N stage (P=0.000) were independent prognostic factors for survival. In the NSM group, T stage (P=0.014) and N stage (P=0.000) were independent prognostic factors for survival.

Conclusion

It was concluded that NSM is common in ESCC and is associated with poor survival.

Nodal skip metastasis in thoracic esophageal squamous cell carcinoma: a cohort study

Background

Nodal skip metastasis is a prognostic factor in some sites of malignancies, but its role in esophageal cancer is still unclear. The present study aimed to investigate occurrence and effect of nodal skip metastases in thoracic esophageal squamous cell carcinoma.

Methods

All 578 patients undergoing esophagectomy for thoracic esophageal squamous cell carcinoma at the Center for Esophageal Diseases located in Padova between January 1992 and December 2010 were retrospectively evaluated. Selection criteria were R0 resection, pathological M0 stage and pathological lymph node involvement. Patients receiving neoadjuvant therapy were excluded.

Results

The selection identified 88 patients with lymph node involvement confirmed by pathological evaluation. Sixteen patients (18.2%) had nodal skip metastasis. Adjusting for the number of lymph node metastases, patient with nodal skip metastasis had similar 5-year overall survival (14% vs. 13%, p = 0.93) and 5-year disease free survival (14% vs. 9%, p = 0.48) compared to patients with both peritumoral and distant lymph node metastases. The risk difference of nodal skip metastasis was: −24.1% (95% C.I. -43.1% to −5.2%) in patients with more than one lymph node metastasis compared to those with one lymph node metastasis; −2.3% (95% C.I. -29.8% to 25.2%) in middle thoracic esophagus and −23.0% (95% C.I. -47.8% to 1.8%) in lower thoracic esophagus compared to upper thoracic esophagus; 18.1% (95% C.I. 3.2% to 33.0%) in clinical N0 stage vs. clinical N+ stage.

Conclusions

Nodal skip metastasis is a common pattern of metastatic lymph involvement in thoracic esophageal squamous cell carcinoma. However, neither overall survival nor disease free survival are associated with nodal skip metastasis occurrence.

Prognostic significance of lymph node characteristics on survival in esophageal squamous cell carcinomas

OBJECTIVES

To investigate the prognostic significance of lymph node characteristics (total number of resected lymph nodes, metastatic lymph node ratio, and metastatic lymph nodes site) on survival in patients with esophageal squamous cell carcinoma.

METHODS

Patients who underwent esophagectomy at Huashan Hospital, Fudan University, between October 1, 2003, and December 31, 2008, were reviewed. Survival data and clinicopathological characteristics were collected.

RESULTS

Among 205 patients, the median overall survival time was 48.0 months and the overall 5-year survival rate was 44.7 %. The independent risk factors for disease-free survival were the metastatic lymph node ratio (P < 0.001) and the number of positive lymph nodes (P < 0.001) and not the total number of resected lymph nodes (Χ (2) = 3.063, P = 0.216). There was no difference in survival between patients with extrathoracic and intrathoracic lymph node metastasis (Χ (2) = 0.295, P = 0.587). No significant relation was found between tumor location and the site of metastatic lymph nodes (rs = 0.125, P = 0.245).

CONCLUSIONS

Our finding revealed that the ratio and the number, but not the site, of metastatic lymph nodes were independent prognostic risk factors in esophageal squamous cell carcinomas. We suggest taking these factors into consideration for better estimation of prognosis.