Node Groups Research Articles

Development and validation of a machine-learning model to predict lymph node metastasis of intrahepatic cholangiocarcinoma: A retrospective cohort study.

Lymph node metastasis in intrahepatic cholangiocarcinoma significantly impacts overall survival, emphasizing the need for a predictive model. This study involved patients who underwent curative liver resection between different time periods. Three machine learning models were constructed with a training cohort (2010-2016) and validated with a separate cohort (2019-2023). A total of 170 patients were included in the training set and 101 in the validation cohort. The lymph node status of patients not undergoing lymph node dissection was predicted, followed by survival analysis. Among the models, the support vector machine (SVM) had the best discrimination, with an area under the curve (AUC) of 0.705 for the training set and 0.754 for the validation set, compared to the random forest (AUC: 0.780/0.693) and the logistic regression (AUC: 0.703/0.736). Kaplan-Meier analysis indicated that patients in the positive lymph node group or predicted positive group had significantly worse overall survival (OS: p < 0.001 for both) and disease-free survival (DFS: p < 0.001 for both) compared to negative groups. An online user-friendly calculator based on the SVM model has been developed for practical application.

SRFACS: A secure and robust framework for anonymous communication systems.

Anonymous communication is crucial for preserving user privacy in various applications, such as anonymous browsing, secure online payments, and electronic voting. However, current systems face significant challenges related to robustness, fault tolerance, and efficient communication management. This paper introduces SRFACS (Secure and Robust Framework for Anonymous Communication Systems), designed to address these issues by integrating advanced cryptographic techniques with a structured communication framework. Traditional anonymous communication systems usually lack sufficient fault tolerance, making them vulnerable to node failures, especially in asynchronous environments. In order to overcome these limitations and ensure that the system can keep running in the event of node failure (especially in an asynchronous environment), SRFACS integrates an improved asynchronous Byzantine Fault Tolerant (ABFT) protocol. We use this protocol to expand the traditional single communication node into a structured node group, and handle up to (n - 1)/3 faulty nodes in these groups, so as to enhance fault tolerance and maintain continuous operation. To efficiently manage inter-group communication, SRFACS utilizes leader nodes to coordinate and streamline the communication processes. To mitigate the risks associated with leader failures, we have implemented an efficient leader change protocol that promptly replaces defective leaders, ensuring uninterrupted system performance. Additionally, to prevent erroneous leader actions from compromising the system, we have introduced an advanced multi-signature scheme. This approach secures communication by requiring multiple signatures for verification processes. Furthermore, we have implemented a reputation incentive mechanism to encourage nodes to maintain optimal performance and avoid malicious behavior. This mechanism evaluates nodes according to their past activities and reliability to achieve dynamic updates of SRFACS node groups. We have conducted rigorous security analyses and component performance evaluations of SRFACS, further confirming its potential as a promising secure communication solution.

The impact of extent of nodal involvement on Stage IIIA(N2) NSCLC outcomes

ObjectivesStage IIIA(N2) non-small cell lung cancer (NSCLC) treatment can depend on the extent of nodal involvement, with surgery considered for limited disease and definitive chemoradiation preferred for bulky or multi-station disease. Evidence to support management is limited. This study evaluated the impact of the extent of Stage IIIA(N2) nodal involvement on outcomes after surgery. MethodsPatients who underwent surgical resection of T1-2N2M0 NSCLC in the Surveillance, Epidemiology, and End Results (SEER) database from 2004-2019 were stratified as having limited (1 positive node) versus more extensive (>1 positive node) nodal disease, and survival was evaluated with Kaplan-Meier and Cox analyses. ResultsOf the 6,933 patients identified surgical patients, 2,129 (30.7%) had limited nodal disease while 4,804 (69.3%) had more extensive nodal involvement. The limited nodal group had higher 5-year overall survival than the more extensive node group (39.3% vs 30.3%, p<0.001), and more extensive nodal involvement (Hazard Ratio 1.26, p<0.001) was independently associated with worse survival in Cox analysis. Surgical patients had a higher 5-year overall survival than 1,644 comparable N2 patients with extensive nodal involvement who received definitive chemoradiation (30.9% vs 18.9%, p<0.001). ConclusionsIncreasing nodal involvement is associated with worse survival for Stage IIIA(N2) NSCLC patients but select patients with more extensive nodal disease may still benefit from surgery compared to chemoradiation.

Association of SOX10 Immunohistochemical Expression with Triple Negative Breast cancer

Abstract Background: The term triple-negative breast cancer (TNBC) refers to a particular class of aggressive, poorly differentiated neoplasms that show the absence of estrogen (ER), progesterone (PR), and human epidermal growth factor receptor2 (HER2) antibodies. The aim of this study is to assess the immunohistochemical expression of SOX10 in TNBC, its correlation with tumor grade and other clinicopathologic characteristics. Materials and methods: A Cross sectional study which included thirty paraffin blocks of primary (TNBC) , that were collected from Karbala teaching centre of histopathology in the period (from Jan. 2023 to Dec. 2023). For each of the collected block, two sections were taken. One stained by hematoxylin and eosin and the other was stained by immunohistochemical method for SOX10. Results: SOX10 reported positive in 43% (13) positive cases versus 57% (17) negative cases, this positivity was significantly correlated with pathological grade (p value =0.012) and the pathological stage (p value =0.038). A particular statistical significance was found in association with the lymph node group and distant metastasis. (p value 0.039 and 0.037) respectively. No significant statistical difference between SOX10 expression and the patient’s age, tumor size, presence of Ductal carcinoma in situ (DCIS) and lymphovascular invasion. Conclusion: The study suggested that SOX10 expression is a prognostic biomarker for TNBC. It also highlighted the clinical significance of targeting SOX10 as a promising potential therapeutic target gene for TNBC therapy. Keywords: SOX10; triple negative breast cancer; immunohistochemistry.

The correlation between multi-mode ultrasonographic features of breast cancer and axillary lymph node metastasis.

This study aimed to explore the correlation between multi-mode ultrasonographic features of breast cancer and axillary lymph node metastasis. A total of 196 patients with surgically confirmed breast cancer between September 2019 and December 2023 were included. Data on preoperative B-mode ultrasound (US), color Doppler, and shear wave elastography (SWE) features of breast cancer masses were collected and analyzed to determine their correlation with axillary lymph node metastasis. The area under the receiver operating characteristic curve (AUC) of B-mode US, color Doppler, SWE, and the multi-mode predictive model for evaluating axillary lymph node metastasis were compared. Among the 196 patients, 70 had positive axillary lymph nodes, while 126 had negative axillary lymph nodes. There was no significant difference in the color features between the negative and positive axillary lymph node groups. Multifocality/multicentricity, architectural distortion, microcalcifications, and the "stiff rim" sign in SWE were identified as independent risk factors to predict axillary lymph node metastasis according to binary logistic regression analysis. The AUC of the predictive model based on these independent risk factors was 0.803 (95% CI: 0.739-0.867), which was significantly higher than that of B-mode US or SWE alone. Multifocality/multicentricity, architectural distortion, microcalcifications, and the "stiff rim" sign in SWE were found to be valuable for predicting axillary lymph node metastasis in patients with breast cancer. The predictive model developed in this study, combining the multi-mode ultrasonographic features of breast cancer masses, could serve as a noninvasive and convenient method to predict axillary lymph node status. This approach could aid in clinical decision-making and individualized treatment to improve the prognosis of breast cancer patients.

Evaluation of Treatment Strategies for Patients with Stage IIIA Non-Small Cell Lung Cancer in the Immunotherapy Era

BackgroundOptimal treatment for patients with stage IIIA NSCLC is controversial. Growing evidence indicates surgery with adjuvant or neoadjuvant chemotherapy (SC) may be superior to non-surgical treatments. Direct comparisons have not been performed between SC and chemoradiation with immunotherapy (CRI) among patients diagnosed with stage IIIA NSCLC since consolidation immunotherapy was added to treatment guidelines. MethodsThis retrospective study compared surgical and systemic non-surgical treatments (except targeted therapy) among adults diagnosed with stage IIIA NSCLC 2017-2021. Data was from ConcertAI's curated EHR Patient360™ NSCLC real-world care product. Real-world progression-free survival (rwPFS) and overall survival (rwOS) were evaluated among patients treated with SC or CRI using Kaplan-Meier and Cox proportional hazard methods. Baseline differences were balanced using propensity score-derived inverse probability treatment weights (IPTW). ResultsAmong 1718 eligible, the two main comparator groups (SC and CRI) had 431 (25%) and 576 (34%) patients; 711 patients received chemoradiation or monotherapy. A wide range of treatment strategies was observed across included oncology clinics (e.g., 0–67% clinic patients received surgery). IPTW-adjusted analyses showed reduced hazards in the SC group vs. CRI for rwPFS (HR 0.78, 95% CI: 0.63–0.97) and rwOS (HR 0.63, 95% CI: 0.49–0.82). SC was similarly beneficial for patients across nodal status groups and appeared especially beneficial for patients with resectable squamous-cell tumors. ConclusionStage IIIA NSCLC treatment is highly variable. Real-world studies can provide valuable evidence to support surgery as a treatment option for stage IIIA patients, who currently may only be offered chemoradiation with or without immunotherapy.

Development of an evaluation method for precipitation particle types by using disdrometer data

Abstract A method for evaluating precipitation particle types from the size-fall velocity data observed by disdrometers by combining an expectation-maximization (EM) algorithm and a self-organizing map (SOM) was developed. An EM algorithm was used to estimate the particle size-fall velocity relationships according to previous work, and the SOM map was used to classify the relationships into graupel or snow categories. The method was applied for snowfall data observed by the volume scanning video disdrometer at a site in Sapporo, Japan, and the daily graupel-to-solid precipitation ratio (G/S ratio) from 1 December, 2017 to 28 February, 2018 was obtained. The sensitivity of the results to different SOM configurations, SOM node groupings, and training datasets was also tested. The G/S ratio obtained from the simulation data of a meteorological model was compared as an example of the application of the product created by the new method.

SURGICAL TREATMENT OF RECTAL CANCER WITH PRESERVATION OF THE LEFT COLIC ARTERY AND ICG NAVIGATION

Goal. To analyze the peculiarities of surgical diagnosis of lymphogenic metastasis in patients with colorectal cancer. Generalization of data from Ukrainian and foreign literature, results of randomized studies and meta-analyses. The study is based on the results of observation of 88 patients with colorectal cancer (CRC) of the prospective study group. To analyze the features of surgical diagnostics of lymphogenic metastasis in patients with colorectal cancer. Materials and methods. The results of surgical treatment of 88 patients with rectal cancer were analyzed and systematized. These patients underwent examination and treatment in 2023-2024 at the "Prykarpattian Clinical Oncology Center of the Ivano-Frankivsk Regional Council." The study included patients with stage II-III colorectal cancer (T2-3N0-2M0) without complicated courses. All patients received treatment based on NCCN recommendations. Surgical treatment was performed in standard volume with the removal of all regional lymph node groups and preservation of the left colic artery using real-time lymph node mapping with indocyanine green. All patients were divided into two study groups: Group I included 45 patients who underwent anterior or low anterior resection of the rectum with preservation of the left colic artery. This group was subdivided into two subgroups: Ia – 13 patients who underwent intraoperative indocyanine green injection for real-time lymph node visualization. Ib – 32 patients who did not receive this drug but underwent the same volume of surgery. Group II consisted of 43 patients who underwent anterior or low anterior resection of the rectum with high ligation of the inferior mesenteric artery. This group served as the control group. Results. The main mechanisms of lymphogenic metastasis in colorectal cancer patients in Ivano-Frankivsk were characterized. Literature data on the features of surgical diagnostics of colorectal cancer metastasis were summarized. A review of literature shows the social significance of these studies, as this pathology often leads to patient disability, requiring surgical interventions and further palliative treatment due to the widespread metastasis associated with this disease. The priority task for researchers remains the search for the most effective treatment methods for this pathology, based on randomized studies of colorectal cancer treatment and international protocols. According to the literature, surgical treatment of colorectal cancer remains insufficiently effective at the current stage of oncology. Modern methods offer low 5-year survival rates, emphasizing the need to study factors for individualized treatment. The overall 5-year survival rate for colorectal cancer patients from 2018-2022 was (45.8±2.3)%. The effectiveness of using real-time ICG navigation for lymph node mapping and preservation of the left colic artery in stage II-III (T2-4N1-2M0) rectal cancer patients has been proven. This technique allows for optimal lymphadenectomy, reducing the frequency of surgical complications by 14.7% (p&lt;0.05). Conclusion. Ensuring radical resection of rectal cancer while maximizing blood supply preservation to the anastomosis is the main goal of colorectal surgeons. Over the past two decades, surgical techniques have significantly improved due to advancements in surgical equipment. It is anticipated that surgical technologies will further evolve towards enhancement and individualization in the future. Our procedure serves as an example of modern and personalized rectal cancer surgery.

Quantifying metadata relevance to network block structure using description length

Network analysis is often enriched by including an examination of node metadata. In the context of understanding the mesoscale of networks it is often assumed that node groups based on metadata and node groups based on connectivity patterns are intrinsically linked. This assumption is increasingly being challenged, whereby metadata might be entirely unrelated to structure or, similarly, multiple sets of metadata might be relevant to the structure of a network in different ways. We propose the metablox tool to quantify the relationship between a network’s node metadata and its mesoscale structure, measuring the strength of the relationship and the type of structural arrangement exhibited by the metadata. We show on a number of synthetic and empirical networks that our tool distinguishes relevant metadata and allows for this in a comparative setting, demonstrating that it can be used as part of systematic meta analyses for the comparison of networks from different domains.

Predictive value of methylene blue combined with indocyanine green in sentinel lymph node metastasis in breast cancer: a prospective pilot cohort study.

The status of sentinel lymph nodes is crucial for prognosis and treatment decisions in breast cancer patients. This study aimed to evaluate the predictive value of combined methylene blue and indocyanine green for sentinel lymph node metastasis in breast cancer. This prospective cohort study enrolled 90 clinically node-negative breast cancer patients. Methylene blue and indocyanine green were injected locally before surgery. Sentinel lymph nodes were grouped based on fluorescence intensity and methylene blue staining. A binary logistic regression model was established using 285 lymph node groups to predict metastatic risk. A total of 475 lymph nodes were identified, with 33 being metastatic. The metastatic risk reached 70% for partially blue-stained and weakly fluorescent lymph nodes between 1-2 cm. The model revealed associations between lymph node size, dye staining patterns, and metastatic risks (P<0.05). The AUC of the ROC curve was 0.855. The staining pattern of combined methylene blue and indocyanine green could predict risks of sentinel lymph node metastasis and facilitate rapid intraoperative identification of high-risk lymph nodes.

Pathological Insights into the Subclassification of Diffuse Large B-Cell Lymphoma (NOS)

Abstract Introduction Diffuse Large B-cell Lymphoma, NOS represents around 25-35% of adult Non- Hodgkin’s lymphoma worldwide. According to the 5th edition of WHO for Hematolymphoid neoplasms, DLBCL, NOS encompasses all biologically heterogeneous cases with no clear criteria for inclusion in a specific diagnostic category. The sixth and seventh decade are reported as the median age for DLBCL, NOS in developed countries and a lower median age in developing countries, with slight male predominance (1.2:1). DLBCL, NOS is further subclassified according to cell of origin (COO) using gene expression profiling (GEP) and various immunohistocehmical (IHC) algorithms into germinal center (GCB) and activated B-cell (ABC) subtypes, which carries a prognostic and therapeutic value. Objectives In our study, we have recorded and compared the demographic and pathological data of the DLBCL, NOS subtypes in Ain Shams University Hospitals over the period of three years. Materials and Methods Our retrospective study was conducted in the Department of Histopathology in Ain Shams University Hospitals from January 2020 till December 2022. We retrieved all available cases with a diagnosis consistent with DLBCL, NOS over the period of these three years. A total of 102 cases with available reports, H&amp;E slides and paraffin blocks with sufficient tissue material were included in this study. We recorded the demographic and pathological data of the cases, re-examined available H&amp; E and IHC slides, and applied immunohistochemical (IHC) staining of CD10, and multiple myeloma oncogene 1(MUM1) to remaining DLBCL cases with available paraffin blocks and sufficient tissue material for further subclassification of into GCB and ABC subtypes according to the Hans and modified Hans immuoalgorithms. Finally, we compared and analyzed the demographic and pathological data of both subtypes. Results DLBCL, NOS represented 35.3 % of all NHL cases and 26.19% of all lymphoma cases overall. Out of 102 cases of DLBCL, NOS, 38.2% were GCB while were 61.8 % ABC subtypes. The median age for DLBCL, NOS was 54.9 with male to female ratio of 1.3:1. The ABC subtype showed a higher median age and female affection predominance as compared to GCB. The most affected site overall was the cervical nodal group while stomach, spleen and liver were reported as the most commonly involved extranodal sites. The ABC subtype showed significant association with extra-abdominal nodal groups as compared to the GCB subtype (P = 0.02). The mean Ki-67 proliferation index for DLBCL, NOS was 70.42% while the ABC subtype exhibited higher Ki-67 index with a mean of 74.21 as compared to the GCB subtype with a mean of 69.1 (P = 0.08). A higher proportion of cases of the ABC subtype exhibited &amp;gt;70 % ki-67 proliferation index than the GCB subtype (P = 0.08). Tumor necrosis was noted in 34.8% of cases overall, with higher proportion of cases belonging to the ABC subtype (P = 0.45). Moreover, centroblastic morphological variant was the most common histology reported in both subtypes with less common histological features/variants observed in the ABC subtype; immunoblastic and anaplastic variants. Conclusion In conclusion, incidence of DLBCL, NOS in Ain Shams university hospitals was closely similar to recorded international incidence. According to COO, the ABC subtype was more frequent than the GCB subtype. The ABC subtype was associated with more nodal involvement with a significant predilection to extra- abdominal nodal groups. Moreover, the ABC subtype reported higher overall ki-67 proliferation index with more proportion of cases with &amp;gt; 70% proliferation index and more advanced histological features: immunoblastic/anaplastic variants and necrosis.

Characteristics of lymph node metastasis and short-term outcome of esophageal squamous-cell carcinoma undergoing minimally invasive esophagectomy: a prospective cross-sectional study (with video)

Introduction: Surgery for esophageal squamous-cell carcinoma (ESCC) presents many potential challenges owing to malignant lymph node metastasis, complex procedures and severe postoperative complications. The appropriate lymphadenectomy for ESCC remains controversial. This study aims to evaluate the characteristics of lymph node metastasis and postoperative complications in patients with ESCC undergoing minimally invasive esophagectomy and extended two-field lymph node dissection. Patients and methods: This prospective, single-center, cross-sectional study was conducted from October 2022 to May 2024. All patients with ESCC who underwent minimally invasive esophagectomy and extended two-field lymph node dissection were selected for this study. Postoperative lymph nodes were divided into upper thoracic, middle thoracic, lower thoracic and abdominal lymph node groups. Results: Seventy-four patients with ESCC, including 49 patients who underwent upfront surgery and 25 patients who received preoperative chemoradiotherapy, were selected. The rate of lymph node metastasis in all patients was 39.2%, with 13.6% of patients having upper thoracic metastasis. The factors affecting the rate of lymph node metastasis included preoperative chemoradiotherapy, tumor stage, poor differentiation, lymphovascular/perineural invasion, and tumor size greater than 2 cm, all of which were significantly different (P&lt;0.05). Common postoperative complications included pneumonia (25.7%), recurrent laryngeal nerve (RLN) palsy (10.8%) and anastomotic leak (4.1%). There were no cases required conversion to open surgery, nor any deaths within 90 days postoperatively. Conclusion: Lymph node metastasis in esophageal squamous-cell carcinoma has a high incidence, occurs in the early stages, and is widely distributed in all regions of the mediastinum and abdomen. Minimally invasive esophagectomy and extended two-field lymph node dissection are feasible and safe, with low complication rates.

The Upper Extremity Lymphatic System Is Not Symmetrical in Individuals: An Anatomic Study Utilizing ICG Lymphography and SPECT/CT Lymphoscintigraphy.

We evaluated whether superficial lymphatic anatomy and functional lymph node drainage are symmetric between the right and left upper extremities of healthy female volunteers, and if handedness is associated with symmetry of superficial lymphatic anatomy. Symmetry of lymphatic anatomy has been assumed historically. This assumption of individual anatomic symmetry is being utilized clinically and in research without validation. 36 normal female volunteers underwent bilateral indocyanine green (ICG) lymphography and lymphoscintigraphy of the upper extremities. Eight collecting vessel pathways of each upper extremity were mapped on ICG lymphography. 13 lymph node groups were visualized on lymphoscintigraphy. Symmetry of lymphatic anatomy and functional drainage were established by comparing the right and left extremities of each participant. Hand dominance was assessed by hand grip strength on a hand dynamometer. Among the 36 participants, 10 (28%) showed symmetry of all eight upper extremity lymphatic pathways with ICG. However, only 1 (3%) participant demonstrated complete symmetry amongst the 13 lymph node groups. Total symmetry of lymphatic channels was observed on ICG in seven (39%) participants with hand dominance and three (17%) participants without hand dominance (X2 = 2.215, P = 0.137). Lymphatic anatomy and functional drainage of the upper extremities are not consistently symmetric. Functional nodal drainage as demonstrated by lymphoscintigraphy shows less symmetry than anatomic studies of lymphatic channels using ICG. Symmetric lymphatic anatomy does not appear to correlate with hand dominance. These findings challenge the prevailing assumption of left-right lymphatic symmetry.

Transesophageal endoscopic ultrasound-guided aspiration of mediastinal lymph node. Clinical case

In oncologic practice, metastatic lesions in the mediastinal lymph nodes are primarily associated with lung cancer because of its high morbidity. However, lesions in mediastinal lymph nodes are quite common in the context of various other benign and malignant processes. Therefore, due to the anatomy of this zone, difficulties of visualization of specific lymph node groups, complicated differential diagnosis of benign and malignant processes, the problem of sampling biological materials from the affected area remains important and unsolved. Transesophageal endoscopic ultrasound-guided aspiration is a highly effective and safe method of diagnosis and staging of oncologic diseases associated with metastatic lesions in the mediastinal lymph nodes.

Spectrum of Kikuchi-Fujimoto Disease: A 10-Year Study in a Tertiary Care Centre in South India.

Background Kikuchi-Fujimoto disease (KFD) is a benign lesion of the lymph nodes predominantly seen in younger women and is a condition associated with a good prognosis due to its indolent nature. Since KFD is chiefly a diagnosis of exclusion, it is liable to a higher degree of misdiagnosis. Aim In our study, we attempt to document and analyse the demographic, clinical, and pathological spectrum of cases diagnosed as KFD in a South Indian tertiary care centre over a period of 10 years. Methodology This study was conducted in a retrospective observational manner. Descriptive statistics, including simple frequency and percentage, were used to analyse and summarise the collected data. Results Among the 44 cases obtained, 36 patients were female and eight were males, with an age range of eight to 70 years. The mean age of the affected population was 26 years. Fever was a presenting complaint in 63.6% of cases, and 100% of the cases had lymphadenopathy, chiefly affecting the posterior cervical group of nodes (32/44 cases). Multiple lymph node groups were involved in 22 cases. Most of the nodes were larger than 1 cm in their greatest dimension. On analysis of peripheral smears, 43.2% of patients showed leukopenia. Anti-nuclear antibody (ANA) analysis showed a positive status among two patients, simultaneously establishing the diagnosis of systemic lupus erythematosus (SLE). A history of treated tuberculosis was present in four patients, and one patient had a history of non-compliance with TB treatment. Two patients had recently been diagnosed with TB and were on treatment. The involved nodes were subjected to fine-needle aspiration studies in 13 patients; 12/13 cases showed reactive lymphadenitis, while one case had atypical lymphoid cells. The involved nodes of all the patients were excised and sent for histopathological analysis. The diagnosis of KFD was confirmed on the biopsy. Conclusion In this study, we note the clinical presentations of all the patients diagnosed with KFD and elaborate on the investigations that were employed to verify the diagnosis via exclusion that enabled differentiation of KFD from its close mimickers, which have specific treatment. Keeping this entity in mind is essential in order to prevent overdiagnosis, as most often this condition resolves spontaneously, and in occasional cases, symptomatic treatment is sufficient for its management.

Model‐based clustering in simple hypergraphs through a stochastic blockmodel

AbstractWe propose a model to address the overlooked problem of node clustering in simple hypergraphs. Simple hypergraphs are suitable when a node may not appear multiple times in the same hyperedge, such as in co‐authorship datasets. Our model generalizes the stochastic blockmodel for graphs and assumes the existence of latent node groups and hyperedges are conditionally independent given these groups. We first establish the generic identifiability of the model parameters. We then develop a variational approximation Expectation‐Maximization algorithm for parameter inference and node clustering, and derive a statistical criterion for model selection. To illustrate the performance of our R package HyperSBM, we compare it with other node clustering methods using synthetic data generated from the model, as well as from a line clustering experiment and a co‐authorship dataset.

467. DISTRIBUTION OF LYMPH NODE INVOLVEMENT IN PATIENTS WITH GASTRO-ESOPHAGEAL JUNCTION ADENOCARCINOMA

Abstract Background Curative cancer surgery relies on understanding the lymphatic spread of the tumour to guide lymphadenectomy. The lymphatic involvement in patients with esophageal squamous cell carcinoma (SCC) has been evaluated extensively in large cohort studies from the East where SCC predominates, but the pattern of lymph node spread in gastro-esophageal junction (GEJ) adenocarcinoma is less clear. The primary aim of this study was to compare differences in the pattern of lymph node involvement according to the Siewert classification. Methods Consecutive patients who underwent curative resection for GEJ adenocarcinoma between February 2010 and April 2023 were analysed from a prospectively maintained database. Patient demographic data, neo-adjuvant treatment, operation type and histopathological report data were collected and analysed according to the pathological Siewert classification of GEJ cancer. Results 807 patients who underwent curative surgery for GEJ adenocarcinoma were analysed. The median lymph node yield was 26 (5-81). Comparing positive para-esophageal node yields, Type I and II tumours were similar but both significantly higher than Type III. For positive para-gastric nodes, Type 2 and 3 tumours were similar but both significantly higher than type 1. The significance of these comparisons is presented in table 1. There were no differences comparing other specific nodal groups. Evaluating the effect of node involvement on overall survival positive node status and positive hepatic artery nodes were found to be independent factors adversely affecting survival. Conclusion Siewert type I tumours have greater proximal lymph node involvement compared to type III tumours with higher proportions of positive para-esophageal nodes. Type III tumours on the other hand have higher proportions of para-gastric nodes. Type II tumours have similar para-esophageal node involvement to type 1 tumours and similar para-gastric involvement to type III tumours. Involvement of more specific nodal groups does not seem to vary between the sub types.

776. THREE-FIELD LYMPHADENECTOMY IN ESOPHAGEAL CANCER: EXPERIENCE OF A PORTUGUESE TERTIARY CENTER

Abstract Background The American Joint Committee for Cancer (AJCC) and the Japanese Esophagus Society (JES) differ in the N classification for esophageal cancer, with the former considering the presence of disease in the supraclavicular lymph nodes as M1, and the latter classifying it as loco-regional disease in thoracic esophageal tumors. Patients who would be excluded from a curative intent treatment strategy by the AJCC classification may be candidates for surgery with lymphadenectomy of nodal groups 101 and 104 (JES). Our goal is to understand the impact of three-field lymphadenectomy on morbidity, loco-regional control and overall survival in patients with esophageal cancer. Methods A retrospective cohort study was conducted using data from a prospective database from a single center, which included all consecutive patients undergoing esophagectomy for cancer with either two-field total thoracic lymphadenectomy or three-field lymphadenectomy, between January 2019 and December 2023. Three-field lymphadenectomy was performed for clinical supraclavicular and recurrent nerve nodal involvement and for proximal third tumors. We assessed the morbidity and mortality of both types of surgery, and loco-regional and distant recurrence and overall survival for both groups. Results Of the 279 esophagectomies for cancer, 137 were included for analysis. The median age was 65 years, with 84% males. 58,4% had squamous cell carcinoma and 41,6% adenocarcinoma. 34.3% of the patients had a 3-field lymphadenectomy, 27,7% of these for supraclavicular N+ and 34% for recurrent nerve N+. Conclusion In this large single-center cohort, patients with significant lymph node involvement, treated with esophagectomy and three-field lymphadenectomy, demonstrated comparable loco-regional control and overall survival to more favorable cases, with no statistically significant increase in morbidity and mortality.

Application of tissue pneumoperitoneum technique around lymph nodes in thoracoscopic lung cancer resection.

Thoracoscopic surgery is a primary treatment for lung cancer, with lobectomy and mediastinal lymph node dissection being the predominant surgical approaches for invasive lung cancer. While many thoracic surgeons can proficiently perform lobectomy, thorough and standardized lymph node dissection remains challenging. This study aimed to explore a safer and more efficient surgical method for mediastinal lymph node dissection in lung cancer. A prospective randomized controlled study was conducted, involving 100 patients with right lung cancer who were admitted to our hospital from January 2021 to April 2024 and met the inclusion criteria. These patients were randomly divided into an observation group (tissue pneumoperitoneum technique around lymph nodes group) and a control group (conventional surgery group). Thoracoscopic lobectomy and mediastinal lymph node dissection were performed. Intraoperative and postoperative related indicators were observed to validate the effectiveness and safety of the tissue pneumoperitoneum technique around lymph nodes. The observation group showed a significantly shorter lymph node dissection surgery time compared to the control group, with a statistically significant difference (p < 0.05). The number of lymph nodes dissected in the observation group was significantly higher than that in the control group, with a statistically significant difference (p < 0.05). Although the observation group had slightly more mediastinal lymph node stations dissected than the control group, the difference was not statistically significant (p > 0.05). The total drainage volume within three days postoperatively was comparable between the two groups, with no statistically significant difference (p > 0.05). The observation group had shorter chest tube indwelling time and postoperative hospital stay than the control group, with statistically significant differences (p < 0.05). The incidence of surgical complications was similar between the two groups, and there were no perioperative deaths. The tissue pneumoperitoneum technique around lymph nodes is a more efficient method for mediastinal lymph node dissection in lung cancer, demonstrating safety and feasibility, and is worthy of promotion.

Analysis of the expression of cytokines and chemokines, platelet-leukocyte aggregates, sCD40L and sCD62P in cutaneous melanoma.

Cutaneous melanoma (CM) is a malignancy with a variable incidence worldwide and a poor advanced-stage prognosis. Melanoma growth is closely associated with the immune system. A cross-sectional study was performed on CM patients admitted at the Hospital de Cancer de Pernambuco (HCP) between 2015 and 2018. Fifty-one CM patients were included, and 30 healthy individuals. The study aimed to evaluate the association of platelet activation mechanisms and inflammatory response in patients with cutaneous melanoma. Elevated serum IL10 and low serum TNF levels in CM patients compared to controls (p < 0.05). High IL6 levels in patients with negative lymph nodes LN (-) compared to positive lymph nodes group (LN +, p = 0.0005). Low RANTES levels in patients compared to controls (p < 0.05). Elevated levels of platelet-lymphocyte (PLA), platelet-monocytes (PMA), and platelet-neutrophils (PNA) aggregates were observed in patients compared to controls (p < 0.05). CM patients with stage II had lower PMA levels than stages I and III (p < 0.05). High PMA levels were observed in patients with LN (+) compared to the LN (-) group (p < 0.0001). Patients with SSM had high levels of sCD40L and sCD62P compared to controls (p < 0.05)). High sCD40L levels in stage II compared to the stage III group, and sCD62P in stages I and II compared to the stage III group (p < 0.05). High sCD62P levels in patients with LN (-) compared to the group LN (+) (p < 0.05). It was observed the immunosuppressive profile in CM may favor tumor progression. High levels of platelet-leukocyte aggregates, sCD40L, and sCD62P may be associated with the worst prognosis.