Nodal Anatomy Research Articles

Perioperative outcomes of combined heart surgery and lung tumor resection: a systematic review and meta-analysis

ObjectiveThe prevalence of patients with concomitant heart and lung lesions requiring surgical intervention is increasing. Simultaneous cardiac surgery and pulmonary resection avoids the need for a second operation. However, there are concerns regarding the potentially increased mortality and complication rates of simultaneous surgery and the adequacy of lung exposure during heart surgery. Therefore, we performed a meta-analysis to evaluate the perioperative mortality and complication rates of combined heart surgery and lung tumor resection.MethodsA comprehensive literature search was performed in July 2020. The PubMed, Embase, and Web of Science databases were searched to identify studies that reported the perioperative outcomes of combined heart surgery and lung tumor resection. Two reviewers independently screened the studies, extracted data, and assessed the risk of bias of included studies. Pooled proportions and 95% confidence intervals (95% CI) were calculated by R version 3.6.1 using the meta package.ResultsA total of 536 patients from 29 studies were included. Overall, the pooled proportion of operative mortality was 0.01 (95% CI: 0.00, 0.03) and the pooled proportion of postoperative complications was 0.40 (95% CI: 0.24, 0.57) for patients who underwent combined cardiothoracic surgery. Subgroup analysis by lung pathology revealed that, for patients with lung cancer, the pooled proportion of anatomical lung resection was 0.99 (95% CI: 0.95, 1.00) and the pooled proportion of systematic lymph node dissection or sampling was 1.00 (95% CI: 1.00, 1.00). Subgroup analysis by heart surgery procedure found that the pooled proportion of postoperative complications of patients who underwent coronary artery bypass grafting (CABG) patients using the off-pump method was 0.17 (95% CI: 0.01, 0.43), while the pooled proportion of complications after CABG using the on-pump method was 0.61 (95% CI: 0.38, 0.82).ConclusionCombined heart surgery and lung tumor resection had a low mortality rate and an acceptable complication rate. Subgroup analyses revealed that most patients with lung cancer underwent uncompromised anatomical resection and mediastinal lymph node sampling or dissection during combined cardiothoracic surgery, and showed off-pump CABG may reduce the complication rate compared with on-pump CABG. Further researches are still needed to verify these findings.

Vaccine delivery systems toward lymph nodes.

Strategies of improving vaccine targeting ability toward lymph nodes have been attracting considerable interest in recent years, though there are remaining delivery barriers based on the inherent properties of lymphatic systems and limited administration routes of vaccination. Recently, emerging vaccine delivery systems using various materials as carriers are widely developed to achieve efficient lymph node targeting and improve vaccine-triggered adaptive immune response. In this review, to further optimize the vaccine targeting ability for future research, the design principles of lymph node targeting vaccine delivery based on the anatomy of lymph nodes and vaccine administration routes are first summarized. Then different designs of lymph node targeting vaccine delivery systems, including vaccine delivery systems in clinical applications, are carefully surveyed. Also, the challenges and opportunities of current delivery systems for vaccines are concluded in the end.

The concept of broad exposure facilitates uniportal video-assisted thoracoscopic mediastinal lymph nodes dissection

BackgroundSystematic lymph node dissection is an important part of radical resection for lung cancer. Insufficient incision of the mediastinal pleura results in a tapered or tunnel-like operation surface, which increases the difficulty of uniportal video-assisted thoracoscopic mediastinal lymph node dissection. The objective of this study was to report our concept of broad exposure and investigate the efficacy and safety of this concept in uniportal video-assisted thoracoscopic mediastinal lymph nodes dissection.MethodsWe retrospectively analyzed the clinical data of the 204 non-small cell lung cancer patients who underwent uniportal video-assisted thoracoscopic surgery for anatomical lobectomy and systematic lymph node dissection following the concept of broad exposure. SPSS 23.0 software was used for statistical analysis.ResultsAll operations were completed under uniportal video-assisted thoracoscopic surgery following the concept of broad exposure. The median surgery time was 102 (range, 76–285) minutes and the median blood loss was 50 (range, 20–900) milliliters. The median chest tube duration time was 2 (range, 1–6) days, the median postoperative hospital duration time was 5 (range, 4–10) days. The median number of dissected lymph node stations and dissected lymph nodes were 8 (range,6–9) and 15(range,12–19), respectively. The median number of dissected mediastinal lymph nodes stations and dissected mediastinal lymph nodes were 5(range,3–6) and 11(range,10–15), respectively. The up-staging rate of N staging was 6.86%. The postoperative complication rate was 10.29% and there was no perioperative death.ConclusionsAccording to our results, it’s effective and safe to perform uniportal video-assisted thoracoscopic mediastinal lymph nodes dissection following the concept of broad exposure. This new concept not only emphasizes sufficient exposure, but also focuses on protection of important tissues.

Efficacy of CO₂ Infusion for Preoperative Computed Tomographic Angiography with Computed Tomographic Colonography.

BackgroundComputed tomographic colonography (CTC) is useful for patients for whom colonoscopy may be difficult to perform and is widely employed to examine the vasculature prior to colorectal cancer surgery. Computed tomographic angiography (CTA) was shown to be beneficial intraoperatively to manipulate blood vessels and prevent vascular injury. Three-dimensional (3D)-CTA combined with CTC (3D-CTA with CTC) is useful for preoperative evaluations of the anatomy of mesenteric vessels, colon, and lymph nodes. We observed that when the intestine was dilated with carbon dioxide (CO2), the arteriovenous delineation was often more pronounced than without CO2. To clarify the effects of gas injection with and without CO2 on hemodynamics and vascular passage, we compared the effect of contrast for blood vessels.Material/MethodsThirty patients with resectable colorectal cancer who underwent a preoperative CT examination at our institution from January to October 2019 were study participants. Of these, 15 underwent 3D-CTA and 15 had 3D-CTA with CTC. Three board-certified radiologists independently and blindly evaluated 18 blood vessels. CT values for each blood vessel were measured on each image.ResultsCT values for 3D-CTA with CTC were significantly higher with CO2 than without CO2. The quality of 3D-CTA with CTC images for visualization of blood vessels was also significantly greater than that of 3D-CTA, especially those of arterial and intramesenteric venous systems.ConclusionsBased on the higher image quality and CT values obtained by 3D-CTA with CTC for vessels, compared with by 3D-CTA imaging, 3D-CTA with CTC imaging might be useful in evaluating colorectal cancers.

Does 99mTc-tilmanocept, as next generation radiotracer, meet with the requirements for improved sentinel node imaging?

Introduction and objectivesTo evaluate the migration of 99mTc-tilmanocept from the injection site (IS) as well as the uptake in sentinel nodes (SNs) and non-SNs for lymphatic mapping in patients with breast cancer and melanoma, scheduled for SN biopsy after interstitial tracer administration. Materials and methodsFor 29 primary tumours in 28 patients (mean age: 62y, range: 45–81y) scheduled for SN biopsy planar images were acquired 10 and 120min after administration of 74MBq 99mTc-tilmanocept, in order to evaluate lymphatic drainage as well as uptake ratios between injection site (IS), SN and non-SN. SPECT-CT was performed immediately after delayed planar images to enable anatomical lymph node localization. ResultsSNs were visualized in all patients (100%) with drainage to 34 basins. Uptake in non-SNs was perceived in 16 basins (47%). Number of SNs was concordant between early and delayed images in all basins excepting five (86%). In 24 patients tracer migrated to one lymph node basin (LNB), in three to 2 and in one to 4. When IS was included (N=29) on image, IS/SN ratio could be measured per LNB. The IS/SN ratio at 2h compared to 15min decreased with an average of 66% (range: 15–96%). SN/non-SN 2h ratio in LNBs with visible non-SNs averaged 6.6 (range: 2.3–15.6). In 9 patients with two SNs SN1/SN2 ratio averaged 1.9 on delayed images. At histopathology, SNs were found to be tumour positive in 7 basins (20%). Conclusion99mTc-tilmanocept appears to meet the requirements for improved SN imaging in breast cancer and melanoma on the basis of early and persistent SN visualization frequently accompanied by no or markedly less non-SN uptake. This is associated to rapid migration from the injection site together with increasing SN uptake and retention as expressed by decreasing IS/SN and persistently high SN/non-SN ratios. Further head-to-head comparison of 99mTc-tilmanocept with standard SN radiotracers in larger series of patients is necessary.

Anatomical characterization of the inguinal lymph nodes using microcomputed tomography to inform radical inguinal lymph node dissections in penile cancer.

Radical inguinal lymph node dissections (rILND) for penile cancer risk significant postoperative lymphocele and lymphedema. However, reducing the risk of lymphatic complications is limited by our understanding of lymphatic anatomy. Therefore, this study aims to elucidate the lymphatic anatomy within the current surgical borders of a rILND. To visualize the position of the lymph nodes, tissue packets excised from the inguinal region of five fresh, male cadavers were imaged using microcomputed tomography (µCT). To standardize the position, rotation and size between specimens, each lymph node packet was aligned using a Generalized Procrustes analysis. There was a median of 13.5 lymph nodes (range = 8-18) per packet, with the majority (99%) clustered within a 6 cm radius of the saphenofemoral junction; a region 39%-41% smaller than current surgical borders. No difference existed between the number of nodes between sides, or distribution around the saphenofemoral junction. This study provides the first 3D, in situ, standardized characterization of lymph node anatomy in the inguinal region using µCT. By using knowledge of the normal lymphatic anatomy, this study can help inform the reduction in borders of rILND to limit disruption and ensure a complete lymphadenectomy.

Anatomy of Pelvic Lymph Nodal Stations and Their Role in Staging of Rectal Cancers

Abstract Lymph node involvement is common in rectal cancer and is an important factor in cancer staging, prognosis, and treatment planning. Understanding pelvic lymph node anatomy is crucial for diagnostic radiologists in order to provide accurate information on nodal involvement for surgical teams. This paper reviews pelvic lymph node anatomy as it relates to locoregional versus non-locoregional nodal disease, surgical approaches to rectal cancer with nodal involvement, and the importance of standardized rectal cancer imaging reports.

Evidence for persistent radiation-related injury to the immune system in patients with local breast cancer.

e15189 Background: Clinical data in multiple tumors has demonstrated that the inadvertent radiation of circulating lymphocytes causes grade III-IV lymphopenia which is associated with worse outcomes in cancer patients and failure to respond to immunologic interventions. Murine data from our lab demonstrated that radiation to the brain results in striking changes in the anatomy and cellularity of distant unirradiated lymph nodes. This study was designed to understand the relationship between local radiation and the depletion of distant unirradiated lymph nodes in humans which has not been previously studied. Methods: Adult women with breast cancer who had undergone prior mastectomy with pathology, labs, and radiation data available at our institution were enrolled at the time of their deep inferior epigastric perforator artery (DIEP) flap reconstruction. During reconstruction, a single abdominal lymph node was extracted, and subsequently formalin fixed. The pre- and post-treatment lymph nodes of radiated and non-radiated patients were presented in a blinded manner to the hematopathologist. The pathologist described each lymph node and graded the lymph node density as (1) low, (2) low-normal, (3) normal, or (4) high. Results: Seven women have been enrolled (median age 50; range 31-55) with AJCC tumor stages from 1a – 3b (five are hormone positive, and two are triple negative). The reconstruction was completed on average 488.71 + 224.57 days after initial mastectomy. Three of the women received neoadjuvant chemotherapy, and five received adjuvant chemotherapy. Five of the seven women had received radiation (mean 50.9 + 5.6 Gy). The baseline median LN density score in all patients was 4 (range 1-4), with a post mean LN density of 1.2 + 0.4 in the radiation group compared to a mean score of 3 + 1.4 in the control group. Conclusions: Systemic lymphocyte counts remain relatively stable but lymph node density is markedly lower than baseline in 80% of patients who received chest wall irradiation consistent with data from animal model studies. It is important to note that this effect on the nodes is seen long after the radiation has been completed. [Table: see text]

Neoadjuvant chemotherapy followed by curative-intent surgery for perihilar cholangiocarcinoma based on its anatomical resectability classification and lymph node status

BackgroundThe prognosis of patients with perihilar cholangiocarcinoma have been unsatisfactory. We established new anatomical resectability classification for patients with localized perihilar cholangiocarcinoma and performed neoadjuvant chemotherapy followed by curative-intent surgery based on its resectability classification and lymph node status to improve prognosis. This study aimed to clarify the long-term outcomes and validation of our strategy.MethodsBetween September 2010 and August 2018, 72 consecutive patients with perihilar cholangiocarcinoma were classified into three groups: Resectable (R = 29), Borderline resectable (BR = 23), and Locally advanced (LA = 20), based on the two factors of tumor vascular and biliary extension. R with clinically lymph node metastasis, BR, and LA patients received neoadjuvant chemotherapy using gemcitabine plus S-1.ResultsForty-seven patients (65.3%) received neoadjuvant chemotherapy: R in 8, BR in 21, and 18 in LA, respectively. Fifty-nine patients (68.1%) underwent curative-intent surgery: R in 26, BR in 17, and LA in 6. Five-year disease-specific survival was 31.5% (median survival time: 33.0 months): 50.3% (not reached) in R, 30.0% (31.4 months) in BR, and 16.5% (22.5 months) in LA, which were relatively stratified. Among 49 patients with resection, disease-specific survival was 43.8% (57.0 months): 57.6% (not reached) in R, 41.0% (52.4 months) in BR, and 0% (49.4 months) in LA, which were significantly good prognosis compared to 23 patients without resection (17.2 months). Multivariate analysis identified preoperative high carcinoembryonic antigen levels (more than 8.5 ng/ml) and pT4 as independent poor prognostic factor of patients with resection.ConclusionNeoadjuvant chemotherapy based on resectability classification and lymph node status was feasible, and was considered efficacious in selected patients.

Applied anatomy of pelvic lymph nodes and its clinical significance for prostate cancer:a single-center cadaveric study

BackgroundPelvic lymph node dissection (PLND) is one of the most important steps in radical prostatectomy (RP). Not only can PLND provide accurate clinical staging to guide treatment after prostatectomy but PLND can also improve the prognosis of patients by eradicating micro-metastases. However, reports of the number of pelvic lymph nodes have generally come from incomplete dissection during surgery, there is no anatomic study that assesses the number and variability of lymph nodes. Our objective is to assess the utility of adopting the lymph node count as a metric of surgical quality for the extent of lymph node dissection during RP for prostate cancer by conducting a dissection study of pelvic lymph nodes in adult male cadavers.MethodsAll 30 adult male cadavers underwent pelvic lymph node dissection (PLND), and the lymph nodes in each of the 9 dissection zones were enumerated and analyzed.ResultsA total of 1267 lymph nodes were obtained. The number of lymph nodes obtained by limited PLND was 4–22 (14.1 ± 4.5), the number obtained by standard PLND was 16–35 (25.9 ± 5.6), the number obtained by extended PLND was 17–44 (30.0 ± 7.0), and the number obtained by super-extended PLDN was 24–60 (42.2 ± 9.7).ConclusionsThere are substantial inter-individual differences in the number of lymph nodes in the pelvic cavity. These results have demonstrated the rationality and feasibility of adopting lymph node count as a surrogate for evaluating the utility of PLND in radical prostatectomy, but these results need to be further explored.

Colorectal cancer treated by resection and extended lymphadenectomy: patterns of spread in left- and right-sided tumours.

Whether tumour side affects the anatomical extent and distribution of lymph node metastasis in colon cancer is unknown. The impact of tumour side on the anatomical pattern of lymphatic spread in colon cancer was assessed. Patients with stage III colon cancer from a Japanese multi-institutional database who underwent extensive (D3) lymphadenectomy, which is similar in concept to complete mesocolic excision with central venous ligation, were divided into groups with right- and left-sided tumours. Based on location, mesenteric lymph nodes were categorized as paracolic (L1), intermediate (L2) or central (L3). The Kaplan-Meier method was used to evaluate disease-free survival (DFS) and overall survival (OS), and multivariable Cox models were used to evaluate the association between anatomical lymph node level, metastatic pattern and outcome. A total of 4034 patients with stage III colon cancer (right 1618, left 2416) were included. Unadjusted OS was worse in patients with right colon cancer (hazard ratio 1·23, 95 per cent c.i. 1·08 to 1·40; P = 0·002), but DFS was similar. Right-sided tumours more frequently invaded L3 nodes than left-sided lesions (8·5 versus 3·7 per cent; P < 0·001). The proportion of patients with a skipped pattern of lymphatic spread was higher in right than in left colon cancer (13·7 versus 9·0 per cent; P < 0·001). In multivariable analysis, invasion of L3 nodes was associated with worse OS in left but not in right colon cancer. The presence of skipped metastasis was associated with worse DFS in left, but not right, colon cancer. There are significant differences in the pattern of lymph node invasion between right- and left-sided stage III colon cancer, and in their prognostic significance, suggesting that tumour side may dictate the operative approach.

Anatomical Characterization of the Inguinal Lymph Nodes Using Micro‐Computed Tomography to Inform Radical Inguinal Lymph Node Dissections for Metastatic Penile Cancer

Background, Rationale &amp; AimIn men with penile cancer, a radical inguinal lymph node dissection (rILND) is integral to prevent metastasis and improve disease specific survival. Unfortunately, lymphocele and lymphedema are severe post‐surgical complications that are common to this procedure. The development of a modified inguinal lymph node dissection, that greatly reduced the amount of lymphatic resection, was effective at reducing the incidence of lymphedema and lymphocele; however, it was not suited for patients with advanced‐stage disease as it risked an incomplete cancer resection. As such, there exists a clinical need for a novel surgical template ‐ informed by the lymphatic anatomy ‐ to reduce these post‐surgical complications while ensuring a thorough cancer resection. However, the lymphatic anatomy of the inguinal region is not well characterized in the literature, with no definitive location or number of lymph nodes reported. Therefore, this study aims to elucidate the lymphatic anatomy within the current surgical borders of a rILND using human cadavers.MethodologyTo visualize the position of the lymph nodes, tissue packets excised from the inguinal region were imaged using micro‐computed tomography (μCT; 154 μm Locus Ultra CT scanner). To characterize the distribution of lymph nodes within each tissue packet, lymph nodes were segmented by grayscale values in 3D using a modified seed‐growing algorithm (Region Growing v1.5; Kellner, 2011) in MATLAB. To compare anatomy between tissue packets, the segmented lymph nodes were aligned (registered) with one another by translating, scaling, rotating, and mirroring (if necessary) such that they were all superimposed in a common coordinate system. This was achieved using a specimen‐specific transformation matrix that was obtained from a generalized Procrustes analysis performed using the positions of four landmarks from each specimen; the anterior superior iliac spine, pubic tubercle, sapheno‐femoral junction, and sartorius as it crosses the femoral artery. These landmarks were chosen due to their consistency between individuals as well as their use as surgical landmarks.ResultsPreliminary findings from five samples (n=3 cadavers) show a median of 6 lymph nodes (range = 3–7); their anatomical distribution is illustrated in Figure 1. In addition to obtaining more specimens, ongoing work focuses on segmentation of structures in this region, such as saphenous vein and the sartorius muscle, to provide spatial context to the identified lymph node distribution.Significance &amp; ImplicationsThis study provides the first standardized comparison of lymph node anatomy in the inguinal region, and utilizes a novel imaging methodology validated by our lab to study the anatomy of lymphatic tissue in 3D and in situ. In doing so, the anatomy elucidated in this study will help inform refinement to the borders of the radical surgical template, to limit unnecessary resection in an attempt to reduce the incidence of post‐surgical lymphedema and/or lymphocele.The standardized lymph node data after having the generalized Procrustes analysis applied. The dotted lines represent the rILND surgical borders.Figure 1

Lymph Node and Bone Marrow Micrometastases Define the Prognosis of Patients with pN0 Esophageal Cancer.

Background: Pathological routine lymph node staging is postulated to be the main oncological prognosticator in esophageal cancer (EC). However, micrometastases in lymph nodes (LNMM) and bone marrow (BNMM) are discussed as the key events in tumor recurrence. We assessed the prognostic significance of the LNMM/BNMM status in initially pN0 staged patients with curative esophagectomy. Methods: From 110 patients bone marrow aspirates and lymph node tissues were analyzed. For LNMM detection immunohistochemistry was performed using the anticytokeratin antibody AE1/AE3. To detect micrometastases in the bone marrow a staining with the pan-keratin antibody A45-B/B3 was done. Results were correlated with clinicopathologic parameters as well as recurrence and death during follow-up time. Results: Thirty-eight (34.5%) patients showed LNMM, whereas in 54 (49.1%) patients BNMM could be detected. LNMM and BNMM positive patients showed a correlation to an increased pT category (p = 0.017). Univariate and multivariate analyses revealed that the LNMM/BNMM status and especially LNMM skipping the anatomical lymph node chain were significant independent predictors of overall survival and recurrence-free survival. Conclusions: This study indicates that routine pathological staging of EC is insufficient. Micrometastases in lymph nodes and the bone marrow seem to be the main reason for tumor recurrence and they are a strong prognosticator following curative treatment of pN0 EC.

The role of sentinel node in early ovarian cancer: a systematic review.

Early ovarian cancer (EOC) is defined as ovarian cancer macroscopically limited to the ovaries at the time of initial diagnosis. Approximately only 25% of patients with ovarian cancer are affected by EOC. This condition requires complete surgical staging, including systematic lymphadenectomy up to the level of the renal vessels, with the consequent risk of complications and morbidity. With the aim to reduce the procedure-related morbidity, sentinel lymph node mapping (SLNm) has been introduced as an experimental procedure in EOC staging. The aim of the present study is to systematically review the available series on this interesting issue. Studies were identified by searching electronic databases. The search was systematically applied to PubMed, ClinicalTrials.gov, Scopus and Web of Science looking for records describing the use of sentinel lymph node technique in EOC from January 1st, 1989 to January 1st, 2019. A total of 10 studies were identified for inclusion. Of the 121 patients involved in these studies, only 43 had a histologically-confirmed diagnosis of EOC and were included in the present analysis. SLN (paraaortic and/or pelvic) overall detection rate (DR) was of 97.6%. The overall sensitivity (SS) and negative predictive value (NPV) of the included cases were 66.7% and 96.6%, respectively. We calculated also NPV, SS and DR based on the anatomical lymph node district, with a value of 100% both in the lumbo-aortic and in the pelvic district and a DR of 83.3% and 43% respectively. This review shows that evidence on SLNm in EOC is still scant. Based on the limited data available, SLNm may provide potentially useful information on nodal status in patients affected by this disease.

Material design for lymph node drug delivery.

A significant fraction of the total immune cells in the body are located in several hundred lymph nodes, in which lymphocyte accumulation, activation and proliferation are organized. Therefore, targeting lymph nodes provides the possibility to directly deliver drugs to lymphocytes and lymph node-resident cells and thus to modify the adaptive immune response. However, owing to the structure and anatomy of lymph nodes, as well as the distinct localization and migration of the different cell types within the lymph node, it is difficult to access specific cell populations by delivering free drugs. Materials can be used as instructive delivery vehicles to achieve accumulation of drugs in the lymph nodes and to target specific lymph node-resident cell subtypes. In this Review, we describe the compartmental architecture of lymph nodes and the cell and fluid transport mechanisms to and from lymph nodes. We discuss the different entry routes into lymph nodes and how they can be explored for drug delivery, including the lymphatics, blood capillaries, high endothelial venules, cell-mediated pathways, homing of circulating lymphocytes and direct lymph node injection. We examine different nanoscale and microscale materials for the targeting of specific immune cells and highlight their potential for the treatment of immune dysfunction and for cancer immunotherapy. Finally, we give an outlook to the field, exploring how lymph node targeting can be improved by the use of materials.

Анатомія глибокої кори лімфатичних вузлів лабораторних тварин

Анатомія глибокої кори лімфатичних вузлів лабораторних тварин

VATS lymph node dissection and staging: the Southampton experience

Background: We set out to describe the Southampton experience with video-assisted thoracoscopic surgery (VATS) mediastinal nodal dissection. We aim to discuss our refined technique and the rationale behind it, as well as complications, caveats and trouble shooting. We describe our experience about how to avoid injury to the recurrent laryngeal nerves (RLNs). Methods: This is an observational descriptive review of the operation notes and video recordings of patients undergoing VATS mediastinal systematic nodal dissection (SND) performed during major pulmonary resections for non-small cell lung cancer (NSCLC). VATS-SND was routinely performed at the time of anatomical resection. Our SND conformed to the American College of Surgery Oncology Group (ACOSOG) Z0030 trial definition of SND. In addition, we routinely explore stations 3a, 3p, 4L and 2L. The majority of cases were performed using monopolar diathermy, but in the last 2 years this was replaced by a bipolar energy device. Knowledge about the nodal anatomy and that of the RLN was obtained by dissecting freshly embalmed human cadavers at the All India Institute of Medical Sciences. Results: Five video clips summarizing our current state of experience are presented. These include right nodal harvesting, left nodal harvesting, across midline harvesting of specific nodes, how to avoid damage to the RLN, complications and troubleshooting. Between 2007–2017, we operated on 600 patients (240 left side, 40%). Bleeding in excess of 500 mL which was directly related to SND occurred 3 times. Immediate conversion to thoracotomy was required in one case, and 2 cases required postoperative VATS re-exploration. There were three port-access site metastases, but none of the patients had nodal micrometastases. Three phrenic nerve palsies are reported, one right and two left-sided. There was no RLN palsy on the right side and 3 on the left side (1.3%). Two RLN palsies were due to thermal injury and one due to inadvertent transection of the descending vagal trunk. There was no RLN palsy attributable to energy spray after changing practice from monopolar to bipolar diathermy. The ligamentum arteriosum had to be transected in four patients without complications. Conclusions: Cumulative experience in a large throughput centre has improved the safety record of VATS comprehensive mediastinal nodal dissection. VATS allows the surgeon to access all nodal stations consistently, safely and with minimal complications. A better understanding of the RLN anatomy and the use of a bipolar energy device have contributed to the significant drop in phrenic and RLN palsies in our experience.

Computational assessment of the functional role of sinoatrial node exit pathways in the human heart.

AimThe human right atrium and sinoatrial node (SAN) anatomy is complex. Optical mapping experiments suggest that the SAN is functionally insulated from atrial tissue except at discrete SAN-atrial electrical junctions called SAN exit pathways, SEPs. Additionally, histological imaging suggests the presence of a secondary pacemaker close to the SAN. We hypothesise that a) an insulating border-SEP anatomical configuration is related to SAN arrhythmia; and b) a secondary pacemaker, the paranodal area, is an alternate pacemaker but accentuates tachycardia. A 3D electro-anatomical computational model was used to test these hypotheses.MethodsA detailed 3D human SAN electro-anatomical mathematical model was developed based on our previous anatomical reconstruction. Electrical activity was simulated using tissue specific variants of the Fenton-Karma action potential equations. Simulation experiments were designed to deploy this complex electro-anatomical system to assess the roles of border-SEPs and paranodal area by mimicking experimentally observed SAN arrhythmia. Robust and accurate numerical algorithms were implemented for solving the mono domain reaction-diffusion equation implicitly, calculating 3D filament traces, and computing dominant frequency among other quantitative measurements.ResultsA centre to periphery gradient of increasing diffusion was sufficient to permit initiation of pacemaking at the centre of the 3D SAN. Re-entry within the SAN, micro re-entry, was possible by imposing significant SAN fibrosis in the presence of the insulating border. SEPs promoted the micro re-entry to generate more complex SAN-atrial tachycardia. Simulation of macro re-entry, i.e. re-entry around the SAN, was possible by inclusion of atrial fibrosis in the presence of the insulating border. The border shielded the SAN from atrial tachycardia. However, SAN micro-structure intercellular gap junctional coupling and the paranodal area contributed to prolonged atrial fibrillation. Finally, the micro-structure was found to be sufficient to explain shifts of leading pacemaker site location.ConclusionsThe simulations establish a relationship between anatomy and SAN electrical function. Microstructure, in the form of intercellular gap junction coupling, was found to regulate SAN function and arrhythmia.

Imaging of lymphatic drainage from the chest and regional lymph nodes in lymphadenopathies of various etiologies

Introduction and aim. Chest lymphadenopathy is unspecific syndrome found in various diseases. The aim of the study was to give an overview of chest lymph outflow pathways and methods of chest lymphadenopathy imaging. Methods. 60 literature sources were analyzed: 28 in Russian and 32 in international journals. Various radiological methods of chest lymphadenopathy were analyzed as well. Results. A definition of lymphadenopathy, brief description of the chest lymphatic drainage pathways anatomy and modern classification of thoracic lymph nodes are provided in this article. Modern imaging methods of lymphatic drainage and thoracic lymph nodes in lymphadenopathy syndrome are presented: the traditional x-ray techniques, ultrasound, computed tomography, magnetic resonance imaging, SPECT, PET/CT. Conclusion. A problem of chest lymph outflow pathway studying and a problem of chest lymphadenopathy is significant and awaits further investigation. Optimal methods of chest lymphadenopathy imaging are anatomical (CT, US) and functional (SPECT, PET/CT).

Robotic inguinal lymphadenectomy for penile cancer: the why, how, and what.

Squamous cell carcinoma of the penis (SCC-P) demonstrates a reliable pattern of spread to the lymph nodes of the groin. High grade and higher stage (pT1b or greater) SCC-P demonstrate a higher propensity for metastasis to the inguinal lymph nodes. Further, lymphadenopathy progresses in a predictable fashion, from superficial inguinal lymph nodes to deep inguinal lymph nodes to pelvic lymph nodes, with limited survival noted for those patients with progression to pelvic lymph nodes. Fortunately, inguinal lymphadenectomy can provide cure and improvement in RFS for SCC-P. Unfortunately open inguinal lymphadenectomy is associated with significant morbidity. Perhaps owing to this morbidity, inguinal lymphadenectomy is underperformed in the US. In other words, urologists only offer inguinal lymphadenectomy for high risk SCC-P in only a minority of cases and even when performed, lymph node yield is often unsatisfactory (less than 8 nodes per groin). Recently, a laparoendoscopic inguinal lymphadenectomy has been developed as a new approach to offer potentially curative lymph node resection while minimizing morbidity. The robotic platform has since been adapted for this approach and several reports demonstrate significant improvements in morbidity while maintaining oncologic equivalency. This review highlights the rationale for inguinal lymphadenectomy, inguinal lymph node anatomy, and technical considerations and outcomes of laparoscopic and robotic inguinal lymphadenectomy.