Thoracic Duct Research Articles

Trends in Lymphadenectomy for Esophageal/Esophagogastric Junction Cancer

Lymph node (LN) metastasis is recognized to be an important prognostic factor for esophageal cancer (EC). However, there is no worldwide uniform classification system, and no consensus exists on the extent of the lymphadenectomy. Recently, an international observational cohort study was conducted to evaluate the distribution of LN metastasis in EC patients. Moreover, this could be a milestone to establish a standard classification system and provide new insights to determine the extent of LNs that should be target for treatment. With regard to surgical procedures, three-field lymphadenectomy seems to be promising to improve the prognosis with EC patients. However, extended lymphadenectomy could lead to postoperative complications. The development of minimally invasive esophagectomy (MIE) has allowed us to retrieve cervical paraesophageal nodes without cervical incision and reduce the incidence of postoperative complications. Therefore, it may be possible that the era of MIE could propose the modern extent of LN dissection in the future. Additionally, one of the key components in lymphadenectomy for EC was thoracic duct and surrounding tissues. Although there is some evidence of LN metastasis surrounding the TD, the survival benefit of TD resection is still debatable. With regard to esophagogastiric junction cancer, the extent of LN dissection could be determined by the length of esophageal involvement. We believe further understanding of LN metastasis of EC patients will contribute to establish a global standard of treatment and improve their prognosis.

Mediastinal Thoracic Duct Cyst Infection after Endoscopic Submucosal Dissection for Early Esophageal Cancer: A Case Report.

A mediastinal thoracic duct cyst that originates from the thoracic duct is a very rare disease in the mediastinum. There have been no reports of mediastinal thoracic duct cyst infection caused by endoscopic treatment. This is the first case of mediastinal thoracic duct cyst infection after endoscopic submucosal dissection for early esophageal cancer. We herein report a 75-year-old man with mediastinal thoracic duct cyst infection caused by esophageal endoscopic submucosal dissection. In cases where a mediastinal thoracic duct cyst is found before performing endoscopic esophageal treatment, we should carefully consider the potential risk of post-treatment cyst infection.

Congenital chylothorax in a preterm infant with non-immune hydrops: A case report with literature review on treatment options

Congenital chylothorax is rare with an incidence of 1:10,000-24,000 live births. Congenital chylothorax occurs in lymphatic disorders, heart diseases, cancers, chromosomal abnormalities, tracheoesophageal fistula, etc. Acquired causes are due to surgical thoracic duct trauma. Many cases of chylothorax are idiopathic. The case fatality rate is 15% to 57% and reaches 98% in hydrops foetalis. There is no set standard of treatment for congenital chylothorax. Prenatally, thoracentesis or pleuro-amniotic shunts are done. Postnatally, management of cause, drainage, dietary changes, Octreotide, and Sildenafil have variable results. Pleurodesis, pleuroperitoneal shunt, abrasion, thoracic duct ligation, and anastomoses are surgical options.

A novel anatomical description of the esophagus: the supracarinal mesoesophagus.

During thoracoscopic esophageal resection, while performing the supracarinal lymphadenectomy along the left recurrent laryngeal nerve (LRLN) from the aortic arch to the thoracic apex, we observed a not previously described bilayered fascia-like structure, serving as prolongation of the already known mesoesophagus. We retrospectively evaluated 70 consecutively unedited videos of thoracoscopic interventions on esophageal resections for cancer, in order to determine the validity of this finding and to describe its utility for performing a systematic and more accurate dissection of the LRLN and its adequate lymphadenectomy. After mobilization of the upper esophagus from the trachea and tilting the esophagus by means of two ribbons, a bilayered fascia was observed between the esophagus and the left subclavian artery in 63 of the 70 patients included in this study. By opening the right layer, the left recurrent nerve became visualized and could be dissected free in its whole trajectory. Vessels and branches of the LRLN were divided between miniclips. Mobilizing the esophagus to the right, the base of this fascia could be found at the left subclavian artery. After dissecting and clipping the thoracic duct, complete lymphadenectomy of 2 and 4L stations could be performed. Mobilizing the esophagus in distal direction, the fascia continued at the level of the aortic arch, where it had to be divided in order to mobilize the esophagus from the left bronchus. Here, a lymphadenectomy of the aorta-pulmonary window lymph nodes (station 8) can be performed. It seems that from there the fascia continued without interruption with the previously described mesoesophagus between the thoracic aorta and the esophagus. Here we described the concept of the supracarinal mesoesophagus on the left side. Applying the description of the mesoesophagus will create a better understanding of the supracarinal anatomy, leading to a more adequate and reproducible surgery.

Postesophagectomy chylothorax: a review of the risk factors, diagnosis, and management.

Chylothorax is a crucial postoperative complication of esophagectomy. Characterized by the leakage of chyle and lymphatic fluid through the thoracic duct, chylothorax could result in pleural effusion, respiratory distress, shortness of breath, cardiac arrhythmia, electrolyte imbalance, and malnutrition. Postesophagectomy chylothorax is associated with high morbidity and mortality, and its diagnosis and management require prompt and accurate identification of risk factors and treatment strategies. A variety of strategies are available to treat postesophagectomy chylothorax, ranging from conservative management to pharmacological, lymphangiographic, and surgical treatments. This study reviews the physio-anatomical basis, disease presentation, diagnostic methods, risk factors, and management options for postesophageal chylothorax, filling the literature gap, and highlighting the importance of early recognition and timely intervention in improving patient outcomes.

A prospective analysis of robotic three-stage esophagectomy for carcinoma of the esophagus in a tertiary care cancer centre.

e16078 Background: This study is to evaluate the safety and technical feasibility of total robot-assisted three-stage esophagectomy in terms of: Completeness of surgery, margin status, lymph nodes harvested, learning curve, docking time and total operating time, and associated morbidity and mortality. Methods: It is a prospective non-randomised study from Nov 2016 to Nov 2022 with a total of 168 patients. Inclusion criteria: Histologically proven squamous cell carcinoma, adenocarcinoma of the intrathoracic esophagus surgically resectable (T1-3,N0 -1,M0); ECOG performance status: 0,1 or 2. Exclusion criteria: Carcinoma of cervical esophagus; patients unfit for general anesthesia; stage IV disease. Results: In a total of 168 patients, 52% had Squamous cell carcinoma and 48% had Adenocarcinoma; 8% had upper thoracic, 44.5% mid thoracic and 47% lower thoracic lesions. Mean docking time of 33 mins and mean operating time of 321 min. Average hospital stay of 7 days with average of 44 lymph nodes retrieved and mean blood loss of 280 ml. Intra operative complications of RLN injury in 2%, Thoracic duct injury in 1.6%, and Azygous vein injury in 1%.Post operative complications such as delayed gastric emptying in 3.5%, anastomotic leak in 2.9%, pleural effusion in 2.4%, wound infection in 0.6% and re-exploration in 1.7%. Conclusions: Robotic-assisted esophagectomy has its own unique benefits of very low conversion rates, short learning curve, good quality lymphadenectomy in supra-azygous and bilateral recurrent laryngeal nerve area, less painful with faster recovery even in aged patients with significant co-morbidities. Future RCT may confirm the lower incidence of major complications, and similar OS and DFS compared to open approaches.[Table: see text][Table: see text]

Chylothorax as the Initial Manifestation of Follicular Lymphoma

Chylothorax is the presence of chyle in the pleural space, which can occur with any disruption of the thoracic duct or its main tributaries. Here we describe the case of a 64-year-old nonsmoking woman who presented with shortness of breath and had findings of a massive right-sided chylous pleural effusion. She was subsequently diagnosed with high-grade follicular lymphoma and had chest tube placement and rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone therapy with complete response.

Comment on "Prognosis of Patients With Esophageal Carcinoma Following Routine Thoracic Duct Resection: A Propensity-Matched Analysis of 12,237 Patients Based on the Comprehensive Registry of Esophageal Cancer in Japan".

Comment on "Prognosis of Patients With Esophageal Carcinoma Following Routine Thoracic Duct Resection: A Propensity-Matched Analysis of 12,237 Patients Based on the Comprehensive Registry of Esophageal Cancer in Japan".

Use of direct fluorescein sodium lymphography for thoracic duct identification in a dog with idiopathic chylothorax

AbstractA 2‐year‐6‐month‐old, female, neutered Greyhound was diagnosed with idiopathic chylothorax. Surgery was performed, which included thoracic duct ligation, subtotal pericardectomy, total right caudal lung lobectomy, chyli cisterna ablation and pleural port device placement. Fluorescein sodium was injected into a mesenteric lymph node through a right paracostal laparotomy for colourisation of the different branches of the thoracic duct to assist in identification. A sterile ultraviolet torch (LED 395 nm) was used to activate the fluorescent yellow‐green signal, enabling visual assessment of the thoracic duct and its branches. Finally, the different branches were ligated using haemovascular clips. Success of the thoracic duct ligation was assessed by contrast fluoroscopy. The dog recovered well from the surgery, but was euthanased without investigation 4 weeks after the procedure due to anorexia, diarrhoea and abdominal pain. This is the first report of thoracic duct ligation for idiopathic chylothorax in a dog using fluorescein sodium as a fluorophore to help with the identification of all the thoracic duct branches.

Dosimetric Effect of Thymus and Thoracic Duct on Radiation-Induced Lymphopenia in Patients With Primary Lung Cancer Who Received Thoracic Radiation

Radiation-induced lymphopenia is a well-recognized factor for tumor control and survival in patients with cancer. This study aimed to determine the role of radiation dose to the thymus and thoracic duct on radiation-induced lymphopenia. Patients with primary lung cancer treated with thoracic radiation therapy between May 2015 and February 2020 with whole blood count data were eligible. Clinical characteristics, including age, gender, histology, stage, chemotherapy regimen, radiation dosimetry, and absolute lymphocyte count (ALC) were collected. The thymus and thoracic duct were contoured by one investigator for consistency and checked by one senior physician. The primary endpoint was radiation-induced decrease in lymphocytes, defined as the difference in ALC (DALC) before and after radiation therapy. The data of a total of 116 consecutive patients were retrospectively retrieved. Significant correlations were found between DALC and several clinical factors. These factors include stage, chemotherapy or concurrent chemoradiation, biologically effective dose (BED), mean lung dose, mean body dose, effective dose to immune cells (EDIC), mean thymus dose (MTD), and mean thoracic duct dose (MTDD) (all P < .05). Ridge regression showed that DALC = 0.0063 × BED + 0.0172 × EDIC + 0.0002 × MTD + 0.0147 × MTDD + 0.2510 (overall P = .00025 and F = 5.85). The combination model has the highest area under the curve of 0.77 (P < .001) when fitting the logistic regression model on DALC categorized as binary endpoint. The sensitivity and specificity of the combined model were 89% and 58%, respectively. This study demonstrated for the first time that radiation doses to the thymus and thoracic duct are strongly associated with radiation-induced lymphopenia patients with lung cancer. Further validation studies are needed to implement thymus and thoracic duct as organs at risk.

PO-04-059 THORACIC DUCT LEAK AFTER DEFIBRILLATOR IMPLANTATION

Device implantation is a relatively low-risk procedure, however generator pocket complications can still occur. In this case, the device site was complicated by a thoracic duct chylous extravasation leading to lymphatic drainage into a device pocket. Case Report A 55-year-old male with ischemic congestive heart failure and reduced ejection fraction of 30-35% and left bundle branch block >150 milliseconds presented several months after cardiac resynchronization therapy-defibrillation (CRT-D) implantation with device site swelling. The physical exam was notable for an extremely swollen left arm consistent with lymphedema. This swelling slowly enlarged for the past 6 months after implantation. Concern was for device site complication with a slowly evolving hematoma that caused compressive lymph stasis. Decision was made for device extraction and reimplantation. Pictured below (Figure 1) shows that the device pocket actually was filled with lymphatic fluid. Upon further investigation, the thoracic duct was either damaged or obstructed and likely the culprit. The pocket was then evacuated with subsequent device extraction and reimplantation. No immediate complications were noted. Upon follow-up, the device site was normal, and left arm lymphedema was resolved. This case demonstrates a rare complication of device implantation that does not appear to be reported in our literature search. Typically hematoma, infection, erosion, migration, and Twiddler’s Syndrome are the most common complications in device pockets. The thoracic duct typically runs from the superior aspect of the cisterna chyli which is situated at the L2 vertebrae and runs to the lower cervical spine. Termination in 95% of patients are either the internal jugular vein, subclavian vein, or the angle between them. However, termination is typically posterior without a superficial course. Lymphatic obstruction tends to be late presenting and can be easily confused with venous obstruction leading to delays in care. Management of lymphatic drainage usually is removing the obstructive source, however, a low fat diet has shown benefit. Thoracic duct complications in device implantation are rare but can lead to delayed treatment and repeat procedures. Further investigation into such cases may be warranted.

Iteratively stimulated T cells as tools to understand mechanisms of nonlymphoid recirculation

Abstract Memory T cell migration facilitates whole-body immunosurveillance and protection against recurrent infections and cancer. In the absence of inflammation, tissue resident memory T cells (TRM) patrol non-lymphoid tissues (NLT) while effector and central memory T cells (TEM and TCM) are mostly restricted to the blood and the blood/lymph system respectively. Memory T cells that retain the ability to recirculate through all compartments are rare and poorly characterized. Thus, the function of these cells as well as their non-lymphoid tissue entry and egress requirements under homeostatic conditions are not well defined. Using a heterologous prime-boost immunization scheme and adoptive transfers, we have generated an abundant murine memory T cell population that has been exposed to &amp;gt;50 viral infections over the last 10 years. We termed these cells iteratively stimulated T cells (ISTCs). Parabiosis experiments revealed that ISTCs acquired pan-migration properties: they can be found in blood, non-lymphoid tissues, lymph nodes, and thoracic duct lymph (TDL) of the naïve parabiont. ISTCs persist in NLTs like the lung which are usually associated with short-lived TRM populations, and mice harboring recirculating ISTCs are protected from lethal Influenza challenge. These data indicate that establishing recirculating memory T cells might provide a new strategy to generate long-lasting immunity in tissues like the lung. Single cell RNA-sequencing revealed tissue entry and egress target molecules that will be tested in in vivoCRISPR-Cas9 screens to elucidate mechanisms of T cell recirculation. Supported by a grant from SNSF P2B-SP3_200187

Resolution, recurrence, and chyle redistribution after thoracic duct ligation with or without pericardiectomy in dogs with naturally occurring idiopathic chylothorax

To document outcomes of thoracoscopic treatment of idiopathic chylothorax (IC) in dogs with and without constrictive pericardial physiology (CPP) and evaluate patterns of chyle flow redistribution after thoracic duct ligation (TDL). 26 client-owned dogs. In this prospective cohort study, echocardiography and cardiac catheterization were performed to document CPP in dogs with IC. Thoracoscopic TDL with pericardiectomy was performed if CPP was present (TDL/P group). Dogs without evidence of CPP underwent thoracoscopic TDL alone (TDL group). Dogs underwent preoperative, immediate postoperative, and 3-month postoperative CT lymphangiography studies when possible. Perioperative morbidity, resolution and late recurrence rates, and long-term outcome were recorded. 17 dogs underwent TDL, and 9 underwent TDL/P. Twenty-five of 26 (96%) survived the perioperative period. One dog died from ventricular fibrillation during pericardiectomy. Resolution rates for TDL and TDL/P were 94% and 88%, respectively (P = .55), with 1 late recurrence occurring in the TDL group in a median follow-up of 25 months (range, 4 to 60 months). On 3-month postoperative CT lymphangiography studies, ongoing chyle flow past the ligation site was demonstrated in 5 of 17 dogs, of which 1 dog developed recurrence at 13 months postoperatively. In 15 of 17 dogs, chylous redistribution after TDL was principally by retrograde flow to the lumbar lymphatic plexus. In dogs without evidence of CPP, TDL alone was associated with a very good prognosis for treatment of IC. In the absence of CPP, the additional benefit of pericardiectomy in the treatment of IC is questionable.

Differential regulation of lymphatic junctional morphology and the potential effects on cardiovascular diseases.

The lymphatic vasculature provides an essential route to drain fluid, macromolecules, and immune cells from the interstitium as lymph, returning it to the bloodstream where the thoracic duct meets the subclavian vein. To ensure functional lymphatic drainage, the lymphatic system contains a complex network of vessels which has differential regulation of unique cell-cell junctions. The lymphatic endothelial cells lining initial lymphatic vessels form permeable "button-like" junctions which allow substances to enter the vessel. Collecting lymphatic vessels form less permeable "zipper-like" junctions which retain lymph within the vessel and prevent leakage. Therefore, sections of the lymphatic bed are differentially permeable, regulated in part by its junctional morphology. In this review, we will discuss our current understanding of regulating lymphatic junctional morphology, highlighting how it relates to lymphatic permeability during development and disease. We will also discuss the effect of alterations in lymphatic permeability on efficient lymphatic flux in health and how it may affect cardiovascular diseases, with a focus on atherosclerosis.

D67. Functional Outcomes following Microsurgical Thoracic Duct Lymphovenous Bypass

PURPOSE: Thoracic duct (TD) lymphovenous bypass is a novel treatment for patients with symptomatic TD occlusion. Treatment response following surgery has yet to be fully characterized. METHODS: A retrospective review of all nonsyndromic patients undergoing TD bypass between 2019-2022 at our institution was performed. All cases were performed with intraoperative lymphangiography by interventional radiology. Postoperative functional outcome was assessed at one month and was compared to baseline presentation at the time of initial evaluation. RESULTS: TD bypass was attempted in 15 patients and completed in 14. Eight were female with a mean age of 44.8±13.9 yr. Eight patients (57.1%) had isolated TD occlusion at the level of the TD-central venous junction. Presenting pathologies included: chylous ascites (N=9), protein-losing enteropathy (N=6), lower-extremity lymphedema (N=5), and chylothorax/plastic bronchitis (N=5). Lymphovenous anastomosis was performed between the TD and the external jugular vein in ten patients with one undergoing vein grafting. Eight patients (57.1%) saw symptomatic improvement. Four patients saw improvement in lymphedema, three patients had reduced need for paracentesis in the setting of chylous ascites, and one patient had resolution of bronchial lymphatic casts. Six patients did not see any functional change in their condition. Five patients experienced complications (two infections of abdominal source, 2 TD leaks, 1 seroma). Seven of eight patients with positive treatment response had isolated distal TD occlusion without other lymphatic disease or malformation. CONCLUSION: TD lymphovenous bypass is a promising treatment for patients with isolated distal TD occlusion and was associated with improvements in lymphedema and chylous ascites.

PC47. Physiologic Effects of Thoracic Duct Lymphovenous Bypass

PURPOSE: The lymphatic system is still largely enigmatic, but mechanical obstruction at the thoracic duct is one pathology we are starting to treat well. Patients with thoracic duct obstruction who have failed conservative treatment as well as minimally invasive therapies may be candidates for microsurgical lymphovenous bypass. At our institution, we have developed a multidisciplinary, collaborative intraoperative protocol with interventional radiologists. Postoperatively, lymphovenous bypass is thought to cause physiological derangements as a result of the increased venous return, but no data exist on specifically what changes can be expected. We herein report on a case series of thoracic duct lymphovenous bypass patients and their postoperative physiologic changes. METHODS: A retrospective review of all nonsyndromic adult patients who underwent thoracic duct lymphovenous bypass by the senior authors from 2016-2021 was performed. Demographic, preoperative, perioperative, and postoperative data were collected. Postoperative changes in vital signs including oxygen requirements, heart rate, and blood pressure were analyzed. RESULTS: Nine patients were included in the study. Immediate postoperative heart rate increased significantly among this heterogeneous patient population, but within 4 - 6 hours the change in heart rate was no longer significant. Mean arterial pressure and oxygen requirement were not significantly different before and after bypass. CONCLUSION: Thoracic duct lymphovenous bypass appears to be well tolerated in the short-term even in patients with cardiopulmonary comorbidities. Further data are necessary to continue to better understand the resulting physiologic changes and to optimize patient outcomes.

The spectrum of imaging manifestations of Gorham–Stout disease: a novel dynamic contrast-enhanced MR lymphangiography

BackgroundTo describe the radiological features of Gorham–Stout disease (GSD) as evaluated using plain radiography and dynamic contrast-enhanced magnetic resonance lymphangiography (DCMRL) imaging techniques.MethodsClinical and conventional imaging data were retrospectively reviewed for 15 patients with GSD between January 2001 and December 2020. After December 2018, DCMRL examinations were performed for lymphatic vessel evaluation in patients with GSD and reviewed in four patients.ResultsThe median age at diagnosis was 9 years (range: 2 months–53 years). The clinical manifestations were dyspnea in seven patients (46.7%), sepsis in 12 (80.0%), orthopedic problems in seven (46.7%), and bloody chylothorax in seven (46.7%). The common sites of osseous involvement were the spine (73.3%) and pelvic bone (60.0%). Among the non-osseous involvements, peri-osseous infiltrative soft-tissue abnormalities adjacent to the area of bone involvement were the most common (86.7%), followed by splenic cysts (26.7%) and interstitial thickening (26.7%). DCMRL demonstrated weak central conducting lymphatic flow in two patients with abnormal giant tortuous thoracic ducts and no flow in one patient. All patients who underwent DCMRL in this study presented with altered anatomical lymphatics and functional flow with collateralization.ConclusionDCMRL imaging and plain radiography are very useful for determining the extent of GSD. DCMRL is a novel imaging tool for the visualization of abnormal lymphatics in patients with GSD, which helps in further treatment. Therefore, in patients with GSD, it might be necessary to obtain not only plain radiographs but also MR and DCMRL images.

Milky fluid from where? You are about to find out…

Traumatic chylothorax most commonly occurs after thoracic surgeries with a few cases reported in patients after abdominal surgery. Effusions usually are caused by a pleural reaction during the postoperative period. However, this can also occur from disruption of the thoracic duct during the surgical procedure. The initial approach is conservative with supportive measures, including drainage by ultrasound-guided thoracentesis and diet modification, and surgery is rarely needed. Having a medical history preceding abdominal surgery is always important to consider the possibility of a pancreatic pleural fistula, which can be excluded by an abdominal computed tomography. Lymphangiography is considered the gold standard diagnostic tool, but its use is limited to cases unresponsive to conservative measures. In this patient, a lymphangiography or surgical intervention was not performed since the patient improved after initial management with no recurrent pleural effusion. A new pleural effusion after abdominal surgery must include chylothorax in the differential diagnosis.Keywords: Traumatic chylothorax, hiatal hernia repair, thoracic duct, lymphangiography, abdominal computed tomography

The thoracic duct: The final frontier for intervention?

Key Points Thoracic duct obstruction can cause chylothorax, protein‐losing enteropathy, and chylous ascites but there have been few reports of interventional approaches to diagnosis and treatment. This case series demonstrates that direct lymphangiography and measurement of the lympho‐venous pressure gradient can guide successful interventions of the thoracic duct. Refinement of these techniques will improve the diagnosis of lymphatic disorders and potentially reduce the need for surgical intervention.

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.

To clarify whether routine thoracic duct (TD) resection improves the prognosis of patients with esophageal cancer after radical esophagectomy. Although TD resection can cause nutritional disadvantage and immune suppression, it has been performed for the resection of surrounding lymph nodes. 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. 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). 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.