Left Tracheobronchial Nodes Research Articles

Anatomical and topographic features of lymphatic outflow of the heart in an Anglo‐Nubian goat

The lymphatic system of the heart is directly involved in the spread and development of many pathological processes in animals, particularly neoplasias of various etiologies. Precise knowledge of the lymphatic outflow pathways from the heart gives access to close study of pathogenesis. It allows to actively influence the elimination of the process through preventive and therapeutic measures. In this regard, our study aims to explore the anatomical and topographic features of the lymphatic outflow of the heart in an Anglo‐Nubian goat. The material for the study was fifteen corpses of Anglo‐Nubian goats aged from one to two years. The research methods were thin anatomical preparation, ink‐gelatin perfusion of lymphatic heart vessels, perfusion with Gerota's mass and yellow lead paint, and subsequent radiography of the material under study. It was established that subepicardial lymph nodes collect lymph from the endocardium, myocardium, and epicardium. In Anglo‐Nubian goats, the subepicardial lymphatic vessels of the left surface of the left ventricle and the caudal part of the left surface of the right ventricle merge in the sulcus interventricularis paraconalis and sulcus coronarius, forming lymphatic vessels of a higher order. After the fusion of the vessels, the left lymph collector of the heart is formed. It follows the ventral surface of a. pulmonalis, bends around it ventrally or dorsally, and then flows into the left tracheobronchial lymph node. Subepicardial lymphatic vessels of the cranial part of the left surface of the right ventricle and the right surfaces of the right and left ventricles merge in sulcus interventricularis subsinuosus and sulcus coronarius, also forming lymphatic vessels of higher orders named right lymph collector. The vessel passes under auricula dextra, goes to truncus brachiocephalicus, and is guided through it cranially until it flows into the cranial mediastinal lymph node, located in the Anglo‐Nubian goat at the beginning of a. subclavia sinistra. The outflowing lymphatic vessels leave the cranial mediastinal and left tracheobronchial nodes, flow either directly into the thoracic duct or into the common trunk of the mediastinal lymph nodes. The atrial lymphatic vessels of the Anglo‐Nubian goat flow either into the lymphatic vessel of sulcus coronarius or directly into the cranial mediastinal lymph nodes. Thus, according to the results of thу study, it was established that the lymphatic drainage of the heart in a goat of the Anglo‐Nubian breed is carried out in two main ways, dividing into the left and right halves of the heart. Also, according to the research data, in a goat of the Anglo‐Nubian breed, the possibility of varying the outflow of lymph from the atria in two ways was determined.

Feasibility and strategy for left tracheobronchial lymph node dissection in thoracolaparoscopic esophageal cancer surgery.

This study evaluates the feasibility and strategy of left tracheobronchial lymph node (LN) dissection in the surgical treatment of esophageal cancer, and its impact on surgical outcomes following thoracoscopic esophagectomy. Data of 265 patients with thoracic esophageal cancer who underwent thoracoscopic and laparoscopic esophagectomy was retrospectively reviewed. In 80 cases, thoracoscopic esophagectomy was performed without left tracheobronchial LN dissection (group non-4L), while 185 cases underwent thoracoscopic esophageal mobilization with routine left tracheobronchial node dissection (group 4L). We introduced a "mesoesophageal suspension" method in order to facilitate complete dissection of the left tracheobronchial nodes, along with left recurrent laryngeal nerve nodes. Both univariate and multivariate analyses were performed to evaluate risk factors correlated to left tracheobronchial node metastasis. The non-4L group experienced less blood loss than the 4L group (P = 0.009). More mediastinal LNs were dissected in the 4L group (P < 0.001). There was no significant difference with regard to the incidence of major postoperative complications between the two groups. Compared with other LN metastases, the metastatic rate of the left tracheobronchial LNs was relatively lower. Based on multivariate analysis of six factors, lymphatic invasion and subcarinal node metastasis were shown to be strong independent predictors of left tracheobronchial metastasis. Routine thoracoscopic extensive lymphadenectomy, including the left tracheobronchial LN, was technically feasible and safe in patients with esophageal cancer. Using a mesoesophagus suspension technique, we performed a meticulous LN dissection in the upper mediastinal space.

The spread of metastatic lymph nodes to the mediastinum from left upper lobe cancer: results of superior mediastinal nodal dissection through a median sternotomy

This study endeavored to clarify the location, frequency, and prognostic value of metastatic lymph nodes in the mediastinum among patients with left upper lung cancer who underwent complete dissection of the superior mediastinal lymph node through a median sternotomy. Forty-four patients with left upper lobe cancer underwent extended radical mediastinal nodal dissection (ERD), all of whom were analyzed in this retrospective study. The group comprised 12 females and 32 males, with ages ranging from 28 to 70 years (median age, 60 years). Mediastinal nodal status was assessed according to the systems of Mountain/Dresler 7 and Naruke 8. The clinicopathological records of each patient were examined for prognostic factors, including age, sex, histology, tumor size, c-N number, preoperative serum CEA level, metastatic stations and distribution of metastatic nodes according to Naruke's system 8. The superior mediastinal lymph nodes which cannot be dissected through a left thoracotomy (bilateral #1 and #2, #3, right #3a, and right #4 according to Naruke's map 8 were defined as extra-superior mediastinal nodes for left lung cancer (ESMD). Fourteen patients had one or more metastases to mediastinal lymph nodes, among whom the most common metastatic station was the aortic nodes: 71.4% had metastasis to #5 or #6 (57.1% to #5 and 50% to #6). The next most common metastatic station was the left tracheobronchial nodes (42.8%). Metastasis to the ESMD occurred in 7 of the 44 study subjects (16%), representing a 50% rate of occurrence (7/14) among those with mediastinal nodal involvement. Univariate analysis found that CN factor and aortic nodal involvement (#5, #6) were significant predictive factors for ESMD metastasis. Multivariate analysis determined that only aortic nodal involvement was significant (p = 0.008). Furthermore, ESMD metastasis was rare (5.8%) in the absence of aortic node metastasis. The overall survival rate at 5 years was 50% among the patients without ESMD metastasis. However, the survival rate was 32% at 3 years and 0% at 5 years among the seven patients with ESMD metastasis. The aortic lymph node is the most common site of metastasis from left upper lobe cancer. Multivariate analysis demonstrated that aortic nodal involvement was a significant predictive factor for ESMD metastasis. Based upon the rates of metastasis and the post-operative prognosis in our study patients, dissection of aortic nodes and left tracheobronchial nodes may be important for patients with left upper lobe cancer. Whether ESMD dissection has a beneficial effect on prognosis remains controversial.

Last-intercalated node and direct lymphatic drainage into the thoracic duct from the thoracoabdominal viscera.

We clarified the configuration of the mediastinal lymphatics, focusing on the last intercalated lymph node and the direct drainage vessel to the thoracic duct, based on recent anatomical findings. We macroscopically observed the lymphatics during dissections of 205 cadavers in combination with routine histology. We also review the results of injection by other researchers. Efferent vessels draining directly into the thoracic duct or venous angle were frequently found in the following node groups: the right paratracheal node group corresponding to the last intercalated node in 98% of cadavers (201); the brachiocephalic angle node group in 85% of cadavers (174); the right recurrent nerve group in 46% (94); the left superior phrenic node group in 73% (150); the node group at the origin of the left common carotid artery (the preaortico-carotid node) in 37% (76); the pretracheal node group in 25% (51) and the left tracheobronchial node group in 36% (74). Last intercalated nodes appeared common for multiple drainage routes or regional lymphatics. These results were mostly consistent with injection studies by Riquet et al. Direct lymphatic drainage from the esophagus to the thoracic duct was observed in 19% of cadavers (39). Direct lymphatic drainage of lung segments to distant mediastinal nodes is also reviewed. The sentinel node concept is discussed in relation to the above observations. We hypothesize that the most critical sentinel node, if such usage is allowed, is situated as a guard for a limited specific route and for a common drainage route. We term it the "common terminal node".

気管・食道のリンパ系の局所解剖

In function-preserving operations of the esophagus and lung, it is crucial to have a precise knowledge of the mediastinal and deep cervical lymphatics and their relationships to surrounding structures. The lymphatics of the mediastinum and neck, which are associated with the esophagus and run along the trachea, were dissected in detail in several anatomical specimens. The actual photographs taken during the dissection are included for a more complete understanding of the intricate topographical relationships. Although there are numerous transverse connections, the mediastinal lymphatics can be roughly divided into two major ascending pathways: the right and the left. Each pathway can then be subdivided into a superficial pathway along the major blood vessels and a deep pathway along the trachea and esophagus. Various deep right ascending pathways are shown to illustrate the problem of the differing levels at which lymph vesseles leave the paratracheal nodes to reach the right venous angle. Further, the brachiocephalic node group is discussed as the critical intermediary nodes between the superficial and deep pathways. Numerous deep left pathways are also dissected from the left tracheobronchial nodes. Some lymphatics ascend along the left recurrent nerve to finally reach the left venous angle, while some pathways traverse to the right side. Still other pathways directly connect to the thoracic duct.

Topographical anatomy of the bronchomediastinal lymph vessels: Their relationships and formation of the collecting trunks.

This article aims to clarify the topographical relationships of the bronchomediastinal collecting lymph vessels to other structures, in particular the great vessels, the trachea, the esophagus and the mediastinal pleura. Minute dissection was performed on eight cadavers with special reference to the converging collecting lymph vessels which form the bronchomediastinal trunks. On the right side, the trunks were consistently observed on both the right brachiocephalic vein and the subserous surface of the mediastinal pleura (anterior and posterior mediastinal trunks). The pathway from the right recurrent chain nodes ran laterally behind the carotid sheath and led either into the deep cervical nodes situated on the scalenus anterior or directly into the right venous angle. On the left side, the trunks showed varying courses. The nodes from which the trunks arose were constant, and classifiable into three groups: the uppermost paratracheal nodes near the recurrent chain nodes, the anterior mediastinal nodes (the left phrenic nodes) surrounding the phrenic nerve in front of and inferior to the aortic arch (the origin of the superior mediastinal trunk), and the left tracheobronchial nodes (the origin of the inferior mediastinal trunk). The large transverse superficial communicating vessel between the right and left sides was usually found in front of the trachea above the aortic arch; it was often connected to the nodes of the brachiocephalic angle. Deep communications were also found in front of the carina and behind the trachea. These findings allow the collecting vessels from the thoracic viscera to be divided into two pathways on each side: the anterior and posterior mediastinal trunks on the right side, and the superior and inferior mediastinal trunks on the left side. In addition to the four trunks, the superficial communicating vessel between the right and left sides is also drained from the superior mediastinum. The internal mammary lymph chain, which often emptied directly into the venous angle or into the deep cervical nodes, occasionally joined with the right anterior mediastinal trunk or the left superior mediastinal trunk.