Thoracic duct identification with indocyanine green fluorescence to prevent chyle leaks during minimally invasive esophagectomy.

INTRODUCTION: Chylothorax (CT) is a rare yet serious complication after esophagectomy. Identification of the thoracic duct (TD) during esophagectomy is challenging due to its anatomical variation. Real-time identification of TD may help to prevent its injury. Near infra-red imaging with Indocyanine green (ICG) is a novel technique that recently has been used to overcome this issue. METHODS: Patients who underwent minimally invasive esophagectomy for esophageal cancer were divided into two groups with and without ICG. We injected ICG into bilateral superficial inguinal lymph nodes. Identification of TD and its injuries during the operation was evaluated and compared with the non-ICG group. RESULTS: Eighteen patients received ICG, and 18 patients underwent surgery without ICG. Each group had one (5.5%) TD ligation. In the ICG group injury was detected intraoperative, and ligation was done at the site of injury. In all cases, the entire thoracic course of TD was visualized intraoperatively after a mean time of 81.39 min from ICG injection to visualization. The Mean extra time for ICG injection was 11.94 min. In the ICG group, no patient suffered from CT. One patient in the non-ICG group developed CT after surgery that was managed conservatively. According to Fisher's exact test, there was no significant association between CT development and ICG use, possibly due to the small sample size. CONCLUSIONS: This study confirms that ICG administration into bilateral superficial inguinal lymph nodes can highlight the TD and reduce its damage during esophagectomy. It can be a standard method for the prevention of postoperative CT.

Lymphatic drainage dysfunction via narrowing of the lumen of cisterna chyli and thoracic duct after luminal dilation.

BACKGROUND: The chronological pattern of extrahepatic lymphatic vessel progression in the course of chronic liver disease has not been clarified. This study aimed to clarify the chronological changes in lymphatic vessels with liver disease progression. METHODS: This was a prospective cross-sectional study that enrolled a total of 199 patients. The maximum diameter of the cisterna chyli (CC) or terminal thoracic duct (tTD) was measured using computed tomography or ultrasonography, respectively. Changes in the maximum diameters of the CC and tTD were evaluated with patients with chronic liver disease as the pilot set (n = 138). Subsequently, we examined whether CC/tTD could be used to re-allocate unclassified patients by the Baveno-VII criteria to appropriately diagnose clinically significant portal hypertension (CSPH) in the pilot and validation sets. RESULTS: In the pilot set, a scatter-plot showed that both CC and tTD were narrowed as terminal features in chronic liver disease after dilation. Because there was a significant correlation between the CC diameter and hepatic venous pressure gradient (r = 0.724) in unclassified patients, the diagnostic value of CC and tTD for CSPH was good (AUC: 0.961 and 0.913, respectively). After re-allocation, 68 and 27 unclassified patients were reduced to 4 and 5 in the pilot and validation sets, respectively. CONCLUSION: Both the CC and tTD narrow in the course of liver disease after dilation. Moreover, the maximum diameter of the CC and tTD can be used to re-allocate patients who are unclassified according to the Baveno-VII criteria. CLINICAL TRIAL NUMBER: UMIN trial no. 000044857.

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.

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.

Invasive treatment of persistent postoperative chylothorax secondary to thoracic duct variation injury: Two case reports and literature review.

RATIONALE: Postoperative chylothorax is a rare complication after pulmonary resection. Thoracic duct variations may play a key role in postoperative chylothorax occurrence and make treatment difficult. No studies in the literature have reported the successful treatment of chylothorax second to thoracic duct variation by lipiodol-based lymphangiography. PATIENT CONCERNS: A 63-year-old male and a 28-year-old female with primary lung adenocarcinoma were treated by video-assisted thoracoscopic cancer resection, and suffered postoperative chylothorax. Conservative treatment was ineffective, including nil per os, persistent thoracic drainage, fatty food restriction, and somatostatin administration. DIAGNOSIS: Postoperative chylothorax. INTERVENTIONS: Patients received lipiodol-based lymphangiography under fluoroscopic guidance. Iatrogenic injuries were identified at thoracic duct variations, including an additional channel in case 1 and the lymphatic plexus instead of the thoracic duct in case 2. OUTCOMES: Thoracic duct variations were identified by lipiodol-based lymphangiography, and postoperative chylothorax was successfully treated by lipiodol embolizing effect. LESSONS: Thoracic duct variations should be considered after the failure of conservative treatment for postoperative chylothorax secondary to pulmonary resection. Lipiodol-based lymphangiography is valuable for identifying the thoracic duct variations and embolizing chylous leakage.

Cervical thoracic duct cyst: a conservative resolution.

A woman in her 70s presented with an enlarging, asymptomatic palpable mass in the left supraclavicular fossa. The clinical impression was of a lipoma. Imaging showed a cystic lesion with continuity of a tubular structure leading to the carotid sheath. Cytology was consistent with thoracic duct sampling. A diagnosis of the rare entity of a thoracic duct cyst with supraclavicular extension was made. This was managed conservatively via repeated aspirations which reduced the size of the mass.

Management of lymphoma-associated chylothorax by interventional radiology and chemotherapy: a report of five cases.

Chylous effusion is associated with lymphatic obstruction or leakage in mediastinal or abdominal lymph nodes, and is a rare but troublesome complication in patients with malignant lymphomas. Although there is no standard of care, it is often treated with simultaneous chemotherapeutic and non-chemotherapeutic interventions. Here, we describe the cases of five patients with lymphoma-associated chylothorax with the aim of clarifying an effective treatment strategy. All patients achieved a partial response or better for lymphoma. All patients underwent interventional radiology (IVR) procedures, including lymphangiography (LAG) and thoracic duct embolization (TDE). Complete resolution of chylothorax was eventually achieved by IVR procedures or pleurodesis in all patients. No patients experienced serious adverse events related to LAG/TDE. Treatment of chylous effusion required months for most patients (range: 0.2-4.8 months). Our data suggest that a combination of chemotherapy and LAG/TDE is effective for refractory lymphoma-related chylous effusion.

Intra-Nodal Indocyanine Green Injection to Delineate Thoracic Duct During Minimally Invasive Esophagectomy.

INTRODUCTION: Post-operative chylothorax is a dreaded complication after esophagectomy; hence real-time identification of the thoracic duct (TD) may aid in avoiding its injury or promptly tackling injury when it occurs. We utilized intra-nodal injection of Indocyanine green (ICG) dye to delineate TD anatomy while performing esophagectomy for esophageal carcinoma. METHOD: Two ml of 1 mg/ml solution of ICG was injected into the inguinal lymph nodes under ultrasound guidance. TD was checked with the laparoscopic Karl Storz IMAGE1 STM or Robotic da Vinci Xi system. The thoracic esophagus, periesophageal tissue, and lymph nodes were dissected. The TD was visualized throughout the dissection using OverlayTM technology & Firefly mode™ and checked at the end to rule out any dye leak. TD was clipped if any dye leakage or TD injury (TDI) was noted using Near Infra-Red Spectroscopy. RESULTS: Twenty one patients with M:F 13:8 underwent minimally invasive esophagectomy (MIE) [thoracoscopic assisted (n = 15) and robotic-assisted (n = 6)]. TD was visualized in all the cases after a median (IQR) time of 35 (30, 35) min. The median (IQR) duration of the thoracic phase was 150 (120,165) min. TDI occurred in 1 case, identified intra-operatively, and TD was successfully clipped. There were no post-operative chylothorax or adverse reactions from the ICG injection. CONCLUSION: Intra-nodal ICG injection before MIE helps to identify the TD in real-time and is a valuable intra-operative aid to prevent or successfully manage a TD injury. It may help to prevent the dreaded complication of post-operative chylothorax after esophagectomy.

[Disorders of the central lymphatic system]. / Stoornissen in het centrale lymfestelsel.

The central lymphatic system consists of the thoracic duct, cisterna chyli and the retroperitoneal lymphatics through which lymph and chyle flows. Disorders of the central lymphatic system can for instance lead to leakage (chylothorax), accumulation of fluid (lymphedema) and retrograde flow (protein losing enteropathy). Abnormalities in the central lymphatic system were overlooked for years, followed by lack of diagnostic and therapeutic options. This has changed, as the technique of intranodal contrast injection in inguinal lymph nodes brought renewed interest in the central lymphatic system. In this article, the importance of intranodal contrast injection in diagnosis and treatment of disorders of the central lymphatic system will be presented through 3 clinical cases.

Cisterna chyli as an optimal marker of tolvaptan response in severe cirrhotic ascites.

For patients with cirrhosis, no definitive predictor of the efficacy and prognosis of tolvaptan treatment exists. We assessed the cisterna chyli's utility as an optimal marker. We retrospectively enrolled 172 patients with cirrhosis. The effect of tolvaptan was evaluated using post-treatment survival time. The overall response to tolvaptan was 52.3%. The median cisterna chyli diameter was 4.1 mm. Of 172 patients, 100 were included in the pilot set and 72 in the validation set. According to the Youden index, the cisterna chyli diameter's cutoff value was 4 mm, with a sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of 92%, 83%, 86%, 91%, 5.43, and 0.09, respectively, in the pilot set. The area under the curve of the cisterna chyli diameter for evaluating tolvaptan's effect was 0.911 and 0.988 in the pilot and validation sets, respectively. During multivariate analysis, cisterna chyli narrowing and furosemide treatment were significant predictive factors for tolvaptan's insufficient effect. Cumulative liver transplantation-free survival rates were significantly higher in patients with cisterna chyli dilatation than in those without (p = 0.028). Our findings suggest a strong association of cisterna chyli with tolvaptan treatment response in patients with cirrhosis and hepatic edema.

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.

Respiratory Failure in Noonan Syndrome Treated by Microsurgical Thoracic Duct-Venous Anastomosis.

Noonan syndrome is a disorder characterized by central and peripheral lymphatic conducting anomalies, leading to chylothorax, chylous ascites, and metabolic derangement. Novel imaging methods, including dynamic contrast magnetic resonance lymphangiography and intranodal lymphangiography, have allowed for increased visualization of lymphatic pathology. Severe pulmonary insufficiency and chylothoraces developed in a 61-year-old man with Noonan syndrome. Dynamic contrast magnetic resonance lymphangiography and intranodal lymphangiography demonstrated central thoracic duct (TD) occlusion. The patient's condition significantly improved after a microsurgical TD-venous anastomosis assisted by TD catheterization for imaging guidance, resulting in decompression of the lymphatic system and resolution of the pulmonary symptoms.

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.

Recurrent thoracic duct cyst of the left supraclavicular fossa: A retrospective study of 6 observational case series and literature review.

ABSTRACT: The transient occlusion of the terminal thoracic duct is a rare disease responsible for renitent supraclavicular cysts. The aim of this study was to describe the clinical characteristics, evolution, and treatment.A retrospective multicenter study and literature review was carried out. The literature search (PubMed) was conducted including data up to 31 December 2020 and PRISMA guidelines were respected.This study identified 6 observational cases between September 2010 and December 2020. The search results indicated a total of 24 articles of which 19 were excluded due to the lack of recurrent swelling or the unavailability of full texts (n = 5). Fourteen patients (8 from literature) mostly reported a noninflammatory, painless renitent mass in the supraclavicular fossa which appeared rapidly over a few hours and disappeared spontaneously over an average of 8 days (range: from about 2 hours to 10 days). Anamnesis indicated a high-fat intake during the preceding days in all cases and 7 from literature found in the Medline databases. Recurrences were noted in 10 patients. Thoracic duct imaging was performed in all cases to detect abnormalities or extrinsic compression as well as to eliminate differential diagnoses.A painless, fluctuating, noninflammatory, and recurrent swelling of the left supraclavicular fossa in patients evoking an intermittent obstruction of the terminal portion of the thoracic duct was identified. A low-fat diet was found as safe and effective treatment.

Abdominal lymph node metastasis by lymphatic spread through the thoracic duct in patients with non-small-cell lung cancer.

BACKGROUND: Abdominal lymph node metastasis (ALNM) is common in patients with metastatic non-small-cell lung cancer (NSCLC). However, its mechanism of spread remains to be elucidated. We investigated whether thoracic duct has the role as a pathway for ALNM in NSCLC using clinical data. METHODS: We classified ALNM into subgroups by their location and evaluated its prevalence and association with clinical characteristics in 892 patients with metastatic NSCLC. The abdominal lymph nodes were classified into direct or indirect groups depending on whether they drain directly into the trunk (intestinal trunk or lumbar trunks) connected to the cisterna chyli. RESULTS: One hundred-five patients (11.8%) had ALNM. The paraaortic lymph node was most commonly involved, followed by the aortocaval, left gastric, paracaval, and celiac lymph nodes. After grouping the patients by location of ALNM, 56 patients (53.3%) with ALNM were in the "direct only" group, only seven patients (6.7%) were in the "indirect only" group, and 42 patients (40.0%) were in "both" groups. In patients whose intrathoracic lesions were limited to the right thorax, there was a significantly lower prevalence of ALNM (3.4% vs. 14.3%, p < 0.001). On multivariate logistic regression analysis of clinical variables, higher N category was associated with increased risk of ALNM. CONCLUSIONS: This study suggests that the thoracic duct is one of the potential routes of lymphatic spread to the abdominal lymph nodes. Clinicians should assess for the presence of ALNM during staging work-up and follow-up for NSCLC patients with intrathoracic lesion in left thorax and with high N category.

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.