Effect of Resection of the Thoracic Duct and Surrounding Lymph Nodes on Short- and Long-Term and Nutritional Outcomes After Esophagectomy for Esophageal Cancer

Impact of Thoracic Duct Resection on Long-Term Survival After Esophagectomy: Individual Patient Data Meta-analysis

BACKGROUND

Radical esophagectomy, including thoracic duct resection (TDR), has been proposed to improve regional lymphadenectomy and possibly reduce the risk of locoregional recurrence. However, because of its impact on immunoregulation, some authors have expressed concerns about its possible detrimental effect on long-term survival. The purpose of this review was to assess the influence of TDR on long-term survival.

PATIENTS AND METHODS

PubMed, MEDLINE, Scopus, and Web of Science databases were searched through 15 March 2024. Overall survival (OS), cancer specific survival (CSS), and disease-free survival (DFS) were primary outcomes. Restricted mean survival time difference (RMSTD), risk ratio (RR), standardized mean difference (SMD), and 95% confidence intervals (CI) were used as pooled effect size measures. The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) methodology was employed to evaluate the certainty of evidence.

RESULTS

The analysis included six studies with 5756 patients undergoing transthoracic esophagectomy. TDR was reported in 49.1%. Patients' ages ranged from 27 to 79 years and 86% were males. At 4-year follow-up, the multivariate meta-analysis showed similar results for the comparison noTDR versus TDR in term of OS [- 0.8 months, 95% confidence interval (CI) - 3.1, 1.3], CSS (0.1 months, 95% CI - 0.9, 1.2), and DFS (1.5 months, 95% CI - 2.6, 5.5). TDR was associated with a significantly higher number of harvested mediastinal lymph nodes (SMD 0.57, 95% CI 0.01-1.13) and higher risk of postoperative chylothorax (RR = 1.32; 95% CI 1.04-2.23). Anastomotic leak and pulmonary complications were comparable.

CONCLUSIONS

TDR seems not to improve long-term OS, CSS, and DFS regardless of tumor stage. Routine TDR should not be routinely recommended during esophagectomy.

Does Thoracic Duct Ligation at the Time of Esophagectomy Impact Long-Term Survival? An Individual Patient Data Meta-Analysis

Background: Thoracic duct ligation (TDL) during esophagectomy has been proposed to reduce the risk of postoperative chylothorax. Because of its role in immunoregulation, some authors argued that it had an unfavorable TDL effect on survival. The aim of this study was to analyze the effect of TDL on overall survival (OS). Methods: PubMed, MEDLINE, Scopus, and Web of Science were searched through December 2023. The primary outcome was 5-year OS. The restricted mean survival time difference (RMSTD), hazard ratios (HRs), and 95% confidence intervals (CI) were used as pooled effect size measures. The GRADE methodology was used to summarize the certainty of the evidence. Results: Five studies (3291 patients) were included. TDL was reported in 54% patients. The patients' age ranged from 49 to 69, 76% were males, and BMI ranged from 18 to 26. At the 5-year follow-up, the combined effect from the multivariate meta-analysis is -3.5 months (95% CI -6.1, -0.8) indicating that patients undergoing TDL lived 3.5 months less compared to those without TDL. TDL was associated with a significantly higher hazard for mortality at 12 months (HR 1.54, 95% CI 1.38-1.73), 24 months (HR 1.21, 95% CI 1.12-1.35), and 28 months (HR 1.14, 95% CI 1.02-1.28). TDL and noTDL seem comparable in terms of the postoperative risk for chylothorax (RR = 0.66; p = 0.35). Conclusions: In this study, concurrent TDL was associated with reduced 5-year OS after esophagectomy. This may suggest the need of a rigorous follow-up within the first two years of follow-up.

Impact of thoracic duct resection during radical esophagectomy on oncological and survival outcomes: Systematic review

Practice is variable in the inclusion or exclusion of the thoracic duct (TD) as part of the resected specimen and associated lymphadenectomy in radical esophagectomy for esophageal cancer. While some surgeons believe that the removal of TD-associated nodes may improve radicality and survival, others suggest this represents systemic disease and resection may increase morbidity without survival benefit. A systematic review was performed up to March 2023 using the search terms 'esoph∗' AND 'thoracic duct' for relevant articles which compared thoracic duct preservation (TDP) to resection (TDR) in esophagectomy for esophageal cancer. Included studies were required to report relevant oncological outcomes including at least one of overall survival (OS), disease free survival (DFS) and nodal yield. Seven cohort studies were included in data synthesis, including data for 5926 patients. None of the reported studies were randomised controlled trials. All studies originated from Japan or South Korea with almost exclusively squamous cell-type cancer. Nodal yield was higher in TDR groups. TDR was equivalent or inferior to TDP with reference to clinical outcomes (length of stay, morbidity, mortality). A single study reported increased OS in the TDR group while the remaining studies reported no significant difference. Overall study quality was moderate to poor. While an increased nodal yield may be associated with TDR, this may also be associated with higher morbidity, and currently available data does not suggest any survival benefit.

Oncological and physiological impact of thoracic duct resection in esophageal cancer

Despite advances in multidisciplinary treatment, esophagectomy remains the main curative treatment for esophageal cancer. The advantages and disadvantages of thoracic duct (TD) resection have been controversial for decades. We have herein reviewed relevant published literature regarding 'thoracic duct,' 'esophageal cancer,' and 'esophagectomy' describing the anatomy and function of the TD, and incidence of thoracic duct lymph nodes (TDLN) and TDLN metastases, as well as the oncological and physiological effects of TD resection. The presence of lymph nodes around the TD, referred to as TDLN, has been reported previously. The delineation of TDLNs is clearly defined by a thin fascial structure covering the TD and the surrounding adipose tissue. Previous studies have examined the number of TDLNs and the percentage of patients with TDLN metastasis and revealed that each patient had approximately two TDLNs. The percentage of patients with TDLN metastasis was reported to be 6-15%. Several studies have been conducted to compare the survival after TD resection with that after TD preservation. However, no consensus has been reached because all studies were retrospective, precluding firm conclusions. Although the issue of whether the risk of postoperative complications is affected by TD resection is still unclear, resecting the TD has been shown to have a long-term impact on nutritional status after surgery. In summary, TDLNs are quite common and present in most patients, while metastasis in the TDLNs occurs in a minority. However, the oncological value of TD resection in esophageal cancer surgery remains controversial due to varying findings and methodological limitations of previous comparative studies. Considering the potential but unproven oncological benefits and possible physiological drawbacks of TD resection, including postoperative fluid retention and disadvantages in the long-term nutritional outcome, clinical stage, and nutritional status should be considered before deciding whether to perform TD resection or not.

Prognosis of Patients with Esophageal Carcinoma After Routine Thoracic Duct Resection: A Propensity-matched Analysis of 12,237 Patients Based on the Comprehensive Registry of Esophageal Cancer in Japan

OBJECTIVE

To clarify whether routine thoracic duct (TD) resection improves the prognosis of patients with esophageal cancer after radical esophagectomy.

SUMMARY OF BACKGROUND DATA

Although TD resection can cause nutritional disadvantage and immune suppression, it has been performed for the resection of surrounding lymph nodes.

METHODS

We analyzed 12,237 patients from the Comprehensive Registry of Esophageal Cancer in Japan who underwent esophagectomy between 2007 and 2012. TD resection and preservation groups were compared in terms of prognosis, perioperative outcomes, and initial recurrent patterns using strict propensity score matching. Particularly, the year of esophagectomy and history of primary cancer of other organs were added as covariates.

RESULTS

After propensity score matching, 1638 c-Stage I-IV patients participated in each group. The 5 year overall survival and cause-specific survival rates were 57.5% and 65.6% in the TD-resected group and 55.2% and 63.4% in the TD-preserved group, respectively, without significant differences. The TD-resected group had significantly more retrieved mediastinal nodes (30 vs 21, P < 0.0001) and significantly fewer lymph node recurrence (376 vs 450, P = 0.0029) compared with the TD-preserved group. However, the total number of distant metastatic organs was significantly greater in TD-resected group than in the TD-preserved group (499 vs 421, P = 0.0024).

CONCLUSIONS

TD resection did not improve survival in patients with esoph-ageal cancer. Despite having retrieved more lymph nodes, TD resection caused distant metastases in more organs compared to TD preservation. Hence, prophylactic TD resection should not be recommended in patients with esophageal cancer.

Preoperative controlling nutritional status score predicts systemic disease recurrence in patients with resectable biliary tract cancer

INTRODUCTION

This study aimed to evaluate the association between the preoperative Controlling Nutritional Status (CONUT) score, survival outcomes, and recurrence pattern in patients with resectable biliary tract cancer (BTC).

METHODS

A total of 224 BTC patients (gallbladder, n = 69; intrahepatic bile ducts, n = 26; perihilar bile ducts, n = 72; distal bile duct, n = 57) who underwent surgery with curative intent were enrolled. The best cutoff point of the preoperative CONUT score in discriminating survival was determined using χ² scores. The sites of recurrence were subclassified as locoregional or distant.

RESULTS

Patients were subdivided into the CONUT-low (score ≤ 3, n = 156) and the CONUT-high (score > 3; n = 68) groups. In-hospital mortality occurred more frequently in the CONUT-high group than in the CONUT-low group (7.4% vs. 1.3%; p = 0.028). A high preoperative CONUT score was independently associated with worse overall survival (hazard ratio [HR] 1.906, p = 0.001), worse disease-specific survival (HR 1.840, p = 0.006), and worse recurrence-free survival (HR 1.680, p = 0.005). Recurrence developed in 110 (49.1%) patients. A high preoperative CONUT score was independently associated with a higher risk of distant recurrence (HR 2.245, p = 0.001), but not locoregional recurrence. The incidences of distant recurrence at 5 years were 55.4% and 34.2% in the CONUT-high and CONUT-low groups, respectively (p = 0.001).

CONCLUSIONS

The preoperative CONUT score independently predicts survival outcomes and may serve as a surrogate marker of aggressive systemic disease recurrence in patients with resectable BTC.

Is Thoracic Duct Resection Necessary for Esophageal Squamous Cell Carcinoma Patients Treated with Neoadjuvant Chemoradiotherapy? A Propensity-Matched Analysis Based on the Comprehensive Registry of Esophageal Cancer in Japan

BACKGROUND

The thoracic duct (TD) plays an important role in nutrition and immunity but is often resected with the esophagus when dissecting surrounding lymph nodes in patients with esophageal squamous cell carcinoma (ESCC). We examined whether indiscriminate TD resection improved the prognosis of patients with ESCC treated with neoadjuvant chemoradiotherapy (NACRT) followed by esophagectomy.

METHODS

A total of 440 patients treated with NACRT followed by esophagectomy between 2007 and 2012 were analyzed using data from the Comprehensive Registry of Esophageal Cancer in Japan. The propensity score-matched TD resection and TD preservation groups were compared in terms of short- and long-term outcomes.

RESULTS

After matching, there were 85 patients in both groups. No significant differences were found between groups in either overall survival or cause-specific survival rates at 5 years: 44.2% and 49.0% in the TD resection group, and 39.8% and 47.2% in the TD preservation group, respectively. Furthermore, the number of retrieved mediastinal lymph nodes was significantly greater in the TD resection group than in the TD preservation group (26 vs. 15, p < 0.0001). In contrast, TD resection was associated with metastasis to a significantly greater number of distant organs than TD preservation (49 vs. 32, p = 0.049).

CONCLUSIONS

TD resection did not contribute to improved survival in patients with ESCC but did lead to metastases in more organs than TD preservation. Consequently, indiscriminate TD resection might be avoided in patients with ESCC treated with NACRT followed by esophagectomy.

Skeletonizing En Bloc Esophagectomy Revisited: Oncologic Outcome in Association with the Presence of Thoracic Duct Lymph Nodes

BACKGROUND

Skeletonizing en bloc esophagectomy (SEBE) involves the removal of the esophagus en bloc with locoregional soft tissues and lymph nodes, including the thoracic duct (TD); however, its oncologic benefits remain unclear. We evaluated the impact of SEBE on oncologic outcomes in patients with esophageal squamous cell carcinoma.

METHODS

Patients undergoing McKeown esophagectomy without neoadjuvant therapy between 2013 and 2019 were evaluated. Outcomes after SEBE were compared with those after conventional esophagectomy (CE) using propensity score-matched analysis.

RESULTS

Overall, 232 patients were identified, including 133 patients with SEBE and 99 patients with CE. Lymph node metastasis along the TD was identified in 7.5% (10/133) of the SEBE group, and the incidence was closely related with the tumor invasion depth (2.2% in pT1 and 19.0% in pT2-3). Based on the propensity score, 180 patients (90 pairs) were analyzed. Tumor recurrence was identified in 24.4% and 12.2% of CE and SEBE cases, respectively (p = 0.036). The observed difference was due to the higher incidence of locoregional recurrence in CE (10.5% vs. 2.2%; p = 0.024), while the incidence of systemic recurrence was similar (18.6% vs. 12.2%; p = 0.240). The 5-year disease-free survival rate was 83.6% and 62.4% in the SEBE and CE groups, respectively (p = 0.022). Multivariate analysis revealed that SEBE could significantly reduce the risk of recurrence or death in patients with pT2-3 tumors (hazard ratio 0.173, 95% confidence interval 0.048-0.628; p = 0.008).

CONCLUSIONS

SEBE could identify and eradicate lymphatic metastasis along the TD and positively impact disease-free survival, particularly in patients with pT2-3 tumors.

Effectiveness of lymphadenectomy along the thoracic duct for radical esophagectomy

BACKGROUND

There has been much debate on whether to perform TD resection in radical esophagectomy for esophageal cancer from the perspectives of metastatic rate, effect on postoperative hemodynamics, and other factors. The objective of this study was to determine whether TDLN dissection contributes to improved prognosis.

METHODS

This study involved 1211 patients who underwent D2/D3 dissection with TD resection for thoracic esophageal cancer between 1984 and 2020. The lymph nodes along the TD were defined as TDLNs and the remaining No. 112 nodes as non-TDLNs. The metastatic rate in TDLNs and non-TDLNs and their outcomes were compared with those of other thoracic lymph nodes. Correlation with the invasion depth of the main lesion was also analyzed (T0-2 545 patients, T3-4 666 patients).

RESULTS

The metastatic rates in TDLNs/non-TDLNs in all patients were 7.3%/7.5%, respectively, while those in T0-2 were 2.2%/3.9%, and those in T3-4 were 11.5%/10.6%, with both having higher rates in advanced cases. The efficacy index (EI) for lymphadenectomy in T3-4 was 2.94 for TDLNs and 3.44 for non-TDLNs, with no significant difference. The metastatic rate in TDLNs by tumor site was as follows: Ut/Mt/Lt = 1.1/2.4/2.4% (T0-2) and 7.7/14.5/8.4% (T3-4), being especially high (~ 15%) in patients with advanced cases in Mt region. The EI was comparable or higher for TDLNs compared with other group-2 (Mt/Lt) and group-3 (Ut) regional lymph nodes, regardless of site.

CONCLUSIONS

The significance of TD resection was low in T0-2 due to the low metastatic rate but became evident in cases with invasion depth of T3-4. TDLN resection was at least as effective as dissection of other group-2 or -3 lymph nodes, including No. 112 nodes.

Nutritional Outcomes of Thoracic Duct Resection for Radical Esophagectomy by Assessing Body Composition Changes in One Year: A Single-Center Retrospective Study

BACKGROUND

Thoracic duct (TD) resection is performed when the tumor or a metastatic lymph node directly invades the TD, and is sometimes indicated for radical lymphadenectomy during esophagectomy in esophageal cancer patients. However, the effect of TD resection on nutritional status has not been established.

PATIENTS AND METHODS

In total, 174 consecutive patients from October 2015 to March 2019 who underwent radical esophagectomy for esophageal cancer in Toranomon Hospital were classified into thoracic duct preserved group (n = 51) and TD-resected (TD-R) group (n = 123). We compared laboratory data, body composition data from bioelectrical impedance analysis measured preoperatively and at 1 and 12 months after surgery, and postoperative complications between the two groups.

RESULTS

Clinical stage was significantly more advanced in the TD-R group. Total body weight, body mass index, and fat mass continuously decreased in the two groups over 12 months after surgery, and the decreases were statistically greater in the TD-R group at 12 months after surgery. Skeletal muscle mass and fat-free mass decreased over 1 month after surgery and stayed in a reduced state until 12 months after surgery without statistically significant differences between the two groups. TD resection did not increase incidence of postoperative complications (Clavien-Dindo classification ≥ grade III), but TD resection increased incidence of chylothorax.

CONCLUSIONS

Our results suggest that loss of body fat mass, which was a main contributor to body weight loss, was accelerated in the TD-R group, but TD resection does not deteriorate loss of muscle mass at 12 months after surgery.

Prognostic impact of thoracic duct lymph node metastasis in esophageal squamous cell carcinoma

AIM

We have previously reported the existence of lymph nodes surrounding the thoracic duct ( TDLN) and transthoracic esophagectomy (TTE) with thoracic duct (TD) resection increased the number of lymph nodes (LNs) retrieved. The current study aims to evaluate the prognostic impact of TDLN metastasis in esophageal cancer patients subdivided by its location and comparing the patients' survival with those with extra-regional LN metastasis.

METHODS

Patients who underwent TTE with TD resection for esophageal squamous cell carcinoma (ESCC) were reviewed. Patients were classified into those with or without TDLN metastasis, and clinicopathological factors were compared between groups. TDLN was further divided into TDLN-Ut/Mt/Lt based on the location in the mediastinum. The relapse-free survival (RFS) and overall survival (OS) were compared between groups.

RESULTS

Of 232 patients, TDLN metastasis was observed in 17 (7%). RFS and OS were significantly worse in the TDLN metastasis group. TDLN metastasis was shown to be an independent prognostic factor for RFS and OS in the multivariate analysis. The negative prognostic impact of TDLN metastasis was evident in TDLN-Mt/Lt. The RFS and OS of patients with TDLN metastasis were almost identical to those with positive LN metastasis in extra-regional LNs.

CONCLUSION

TDLN metastasis was proven to be a strong prognostic indicator. Although the TDLN has been included in the classification of regional LN in the current staging systems, it could be independently classified from the current regional LNs. Given that neoadjuvant therapy has been a standard, we might need to introduce adjuvant therapy when TDLN metastasis is observed.

Thoracic Duct Resection Has a Favorable Impact on Prognosis by Preventing Hematogenous Spread of Esophageal Cancer Cells: A Multi-institutional Analysis of 2269 Patients

BACKGROUND

The impact of thoracic duct (TD) resection on prognosis is controversial. This study aimed to examine the impact of TD resection.

METHODS

In this six-institution, matched-cohort study, 2269 consecutive patients with esophageal squamous cell carcinoma who underwent esophagectomy between 2000 and 2017 were enrolled for analysis of long-term outcomes, including overall survival (OS), disease-free survival (DFS), cause-specific survival (CSS), and recurrence patterns.

RESULTS

Based on a propensity score, 642 TD-resected and 642 TD-preserved patients with all stages of disease were selected. At 5 years, the TD-resected group had an OS of 57.7%, a DFS of 50.9%, and a CSS of 62.2%. These rates were significantly higher than the corresponding rates of 48.7% (p = 0.0078), 41.0% (p = 0.0297), and 55.3% (p = 0.0473) in the TD-preserved group. The OS in the TD-preserved and TD-resected groups was similar for the patients with cStage 1 or 2 (p = 0.6265), but it was significantly higher in the TD-resected group for the patients with cStage 3 or 4 (p = 0.0052). The incidence of total recurrence did not differ between the two groups. However, the incidence of hematogenous recurrence in the TD-resected group (19.0%) was significantly lower than in the TD-preserved group (26.2%) (p = 0.0021). For cT4a tumors, the incidence of local recurrence in the TD-resected group (2.4%) was significantly lower than in the TD-preserved group (18.4%) (p = 0.0183).

CONCLUSIONS

Performance of TD resection may help to improve prognosis, especially for patients with advanced esophageal squamous cell carcinoma, by reducing hematogenous and local recurrence. Prospective trials are needed to determine whether prophylactic TD resection has a positive impact on the prognosis of patients with esophageal cancer.

The presence of metastatic thoracic duct lymph nodes in Western esophageal cancer patients

BACKGROUND

The thoracic lymphadenectomy during an esophagectomy for esophageal cancer includes resection of the thoracic duct (TD) compartment containing the thoracic duct lymph nodes (TDLN). However, the role of TD compartment resection is still a topic of debate since metastatic TDLNs have only been demonstrated in squamous cell carcinomas in Eastern esophageal cancer patients. Therefore, the aim of this study was to assess the presence and metastatic involvement of TDLNs in a Western population, in which adenocarcinoma is the predominant type of esophageal cancer.

METHODS

From July 2017 to May 2020 all consecutive patients undergoing an open or robot-assisted transthoracic esophagectomy with concurrent lymphadenectomy and resection of the TD compartment in the University Medical Center Utrecht, The Netherlands and the Città della Salute e della Scienza University Hospital in Turin, Italy were included. The TD compartment was resected en bloc and was separated in the operation room by the operating surgeon after which it was macro- and microscopically assessed for (metastatic) TDLNs by the pathologist.

RESULTS

A total of 117 patients with an adenocarcinoma (73%) or squamous cell carcinoma (27%) of the esophagus were included. In 61 (52%) patients TDLNs were found, containing metastasis in 9 (15%) patients. No major complications related to TD compartment resection were observed.

CONCLUSIONS

This is the first study to demonstrate the presence of metastatic TDLNs in adenocarcinomas of the esophagus. This result provides a valid argument to routinely extend the thoracic lymphadenectomy with resection of the TD compartment during an esophagectomy for esophageal cancer.

The effect of prophylactic thoracic duct ligation during esophagectomy on the incidence of chylothorax and survival of the patients: an updated review

BACKGROUND

The role of thoracic duct ligation (TDL) during esophagectomy remains controversial. This review aimed to elucidate the effect of TDL on chylothorax and survival of the patients after esophagectomy for cancer.

METHODS

We searched articles from PubMed, Web of Science, Scopus, Cochrane, and Google Scholar till May 2020 according to the PRISMA guidelines using the terms of [Oesophagectomy OR esophagectomy] AND [chylothorax] AND [thoracic duct ligation]. Only those compared the incidence of chylothorax in patients who ligated or resected the thoracic duct (ligation group) or preserved the thoracic duct (preservation group) were selected.

RESULTS

First, 15 studies including one randomized controlled trial were collected for meta-analysis regarding post-esophagectomy chylothorax. Of these, 3658 patients underwent TDL and 4638 cases preserved the thoracic duct. Both groups showed similar chylothorax rate (odd ratios 0.73 in favor of ligation group; 95% confidence interval [CI] 0.50-1.07, p = 0.11). Second, four studies providing survival information were included for another meta-analysis, and the patients in preservation group demonstrated better 5-year overall survival compared to those in ligation group (odds ratio 1.25; 95% CI 1.08-1.44, p = 0.002).

CONCLUSIONS

The present review provided updated evidence opposing prophylactic TDL during esophagectomy for lowering chylothorax. Considering the harmful effect of TDL on survival of the patients, further well-designed trials should be considered in selected cases under strict supervision.

Minimally invasive oesophagectomy with extended lymph node dissection and thoracic duct resection for early-stage oesophageal squamous cell carcinoma

BACKGROUND

Oesophageal squamous cell carcinoma is an aggressive disease owing to early and widespread lymph node metastases. Multimodal therapy and radical surgery may improve prognosis. Few studies have investigated the efficacy of radical lymph node and thoracic duct resection.

METHODS

Patients with oesophageal squamous cell carcinoma who underwent transthoracic minimally invasive oesophagectomy (TMIE) for cancer at Keio University Hospital between January 2004 and December 2016 were selected. Between 2004 and 2008, TMIE was performed in the lateral decubitus position without thoracic duct resection (standard TMIE). From 2009 onwards, TMIE with extended lymph node and thoracic duct resection was introduced (extended TMIE). Demographics, co-morbidity, number of retrieved lymph nodes, pathology, postoperative complications and recurrence-free survival (RFS) were compared between groups.

RESULTS

Forty-four patients underwent standard TMIE and 191 extended TMIE. There were no significant differences in clinical and pathological tumour stage or postoperative complications. The extended-TMIE group had more lymph nodes removed at nodal stations 106recL and 112. Among patients with cT1 N0 disease, RFS was better in the extended-TMIE group (P < 0·001), whereas there was no difference in RFS between groups in patients with advanced disease.

CONCLUSION

Extended TMIE including thoracic duct resection increased the number of lymph nodes retrieved and was associated with improved survival in patients with cT1 N0 oesophageal squamous cell carcinoma.