Node Count Research Articles

Prognostic factors of survival in patients with non-small cell lung cancer: a competing risk model using the SEER database.

To explore the prognostic factors of survival in non-small cell lung cancer (NSCLC) patients using the competing risk analysis. This was a retrospective cohort study. NSCLC patients with complete data were selected from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. Outcomes were censored, cancer-specific mortality in NSCLC, and other-cause mortality. Gray's test was used in univariable analysis, and a multivariable Fine-Gray competing risk model with backward elimination was used to explore the prognostic factors of survival. The screened variables were incorporated into a random survival forest (RSF) model for the prediction of 1-, 3-, and 5-year survival in patients with NSCLC. Receiver operator characteristic (ROC) curves, calibration curves, the value of area under the curve (AUC), and decision curve analysis (DCA) were used to evaluate the performance. Totally 1,251 eligible patients were included, 678 (54.20%) patients were cancer-specific mortality, and 128 (10.23%) patients were other-cause mortality. The median follow-up time was 26 months. Age, primary site, N stage, M stage, surgery type, tumor size, and lymph nodes (LNs) count were included in the multivariable Fine-Gray model for further analysis (P<0.05). The six most important features (surgery type, tumor size, M stage, LNs count, N stage, and primary site) were included in the competing risk analysis using the RSF model. The value of AUC for predicting 1-, 3-, and 5-year survival in the testing set were 0.796, 0.804, and 0.792, respectively. Calibration curves were well-fitted. DCA curves showed that the RSF model had similar or greater clinical net benefits in survival compared with the 8th edition the American Joint Committee on Cancer (AJCC) staging. The good performance of the RSF model under different surgery types, T, N, and M stages. We conducted a competing risk analysis using the RSF model for predicting the 1-, 3-, and 5-year survival of NSCLC. We generated a web calculator (https://github.com/YingChen19/Prognostic-factors-of-long-term-survival-of-non-small-cell-lung-cancer), which could provide a convenient assessment and could help improve the prognosis and survival of NSCLC.

Importance of Novel Gastric Cancer Prognostic Index in Patients with Locally Advanced Gastric Cancer Who Underwent Radical Gastrectomy and Chemoradiotherapy

Aim: To investigate the significance of the novel gastric cancer prognostic index, which combines albumin and metastatic lymph node count, on the outcomes of patients with locally advanced gastric cancer who received radical gastrectomy and concurrent chemoradiotherapy. Method: Patients who received concurrent chemoradiotherapy following radical gastrectomy between January 2014 and December 2019 were included in this retrospective analysis. According to the literature, the ideal cutoff value for albumin was determined to be 3.5 g/dL. Meanwhile, the optimal cutoff value for metastatic lymph node count was determined using receiver operating characteristic curve analysis. Results: This retrospective study comprised 137 locally advanced gastric cancer patients. The ideal albumin cutoff value was chosen to be the classically referred 3.5 g/dL (&lt; 3.5 versus ≥ 3.5 g/dL), while the results of the receiver operating characteristic curve analysis revealed the ideal metastatic lymph node count cutoff value as 5 (&lt; 5 versus ≥ 5). Hence, the study population was divided into four possible groups: Group 1: albumin ≥ 3.5 g/dL and metastatic lymph node count &lt; 5, Group 2: albumin ≥ 3.5 g/dL and metastatic lymph node count ≥ 5, Group 3: albumin &lt; 3.5 g/dL and metastatic lymph node count &lt; 5, and Group 4: albumin &lt; 3.5 g/dL and metastatic lymph node count ≥ 5. Since there was no significant difference between Group 2 and Group 3 in the analysis, they were combined to create gastric cancer prognostic index-2. The Kaplan-Meier curves revealed that gastric cancer prognostic index-1 and gastric cancer prognostic index-3 had significant differences in progression-free survival (66.0 versus 16.4 months; P &lt; 0.001) and overall survival (66.0 versus 19.5 months, P &lt; 0.001), respectively. The results of the multivariate analysis confirmed the gastric cancer prognostic index grouping’s independent prognostic significance for overall survival (P &lt; 0.001) and progression-free survival (P = 0.05) outcomes. Conclusion: The novel gastric cancer prognostic index may be utilized as an independent and precise prognostic indicator.

Management of Bladder Cancer Patients with Clinical Evidence of Lymph Node Invasion (cN+).

The purpose of this review is to present the current knowledge about the diagnostic and treatment options for bladder cancer (BCa) patients with clinically positive lymph nodes (cN+). This review shows compaction of CT and MRI performance in preoperative prediction of lymph node invasion (LNI) in BCa patients, along with other diagnostic methods. Most scientific societies do not distinguish cN+ patients in their guidelines; recommendations concern muscle-invasive bladder cancer (MIBC) and differ between associations. The curative treatment that provides the best long-term survival in cN+ patients is a multimodal approach, with a combination of neoadjuvant chemotherapy (NAC) and radical cystectomy (RC) with extended pelvic lymph node dissection (ePLND). The role of adjuvant chemotherapy (AC) remains uncertain; however, emerging evidence indicates comparable outcomes to NAC. Therefore, in cN+ patients who have not received NAC, AC should be implemented. The response to ChT is a crucial prognostic factor for cN+ patients. Recent studies demonstrated the growing importance of immunotherapy, especially in ChT-ineligible patients. Moreover, immunotherapy can be suitable as adjuvant therapy in selected cases. In cN+ patients, the extended template of PLND should be utilized, with the total resected node count being less important than the template. This review is intended to draw special attention to cN+ BCa patients, as the oncological outcomes are significantly worse for this group.

Derivation of a Modified Novel Pathologic Nodal Classification System for Non-Small Cell Lung Cancer

<h3>Purpose/Objective(s)</h3> For decades, nodal staging for non-small cell lung cancer (NSCLC) has been based predominantly on location. Given increasing evidence of the prognostic power of quantitative nodal burden across solid tumors, it is possible that positive lymph node (LN+) count is a primary driver of survival among surgically staged patients with NSCLC. <h3>Materials/Methods</h3> Retrospective cohort analysis was performed on patients with NSCLC undergoing upfront surgery and nodal evaluation, excluding those receiving neoadjuvant chemotherapy in the National Cancer Database (NCDB). Tumor stage was recoded to conform to the current American Joint Committee on Cancer, 8^th Edition (AJCC 8E) based on size and tumor extension. The association between number of positive LNs and survival was modeled with restricted cubic splines in multivariable Cox regression analysis. Recursive partitioning analysis (RPA) was used to develop a modified nodal classification system based on nodal factors independently associated with survival. The proposed nodal classification system was independently validated in patients with NSCLC, now allowing for patients who received neoadjuvant chemotherapy ± radiation, from Surveillance, Epidemiology, and End Results-18 (SEER-18). <h3>Results</h3> Overall, 126,473 patients (62,428 men [49.4%]; mean [SD] age, 67.1 [9.9] years; 32,958 node-positive patients) were included in the NCDB discovery cohort. Mortality risk increased continuously with increasing number of positive LNs in multivariable analysis, with the greatest correlation with the first 3 LN+ (0-3 LN+: HR per LN, 1.38; 95% CI, 1.36-1.41; P<0.001; ≥4 LN+: HR per LN, 1.06; 95% CI, 1.05-1.07; P<0.001). Location of LN (ipsilateral mediastinum) was also a predictor of survival (HR, 1.30; 95% CI, 1.24-1.36; P<0.001). Univariate RPA identified six clusters of patients stratified only by nodal count and not by LN location. On multivariable analysis, these groups demonstrated continuously increasing and non-overlapping mortality risk: N0 (0 LN; reference); N1a (1 LN+; HR, 1.68; 95% CI, 1.61-1.75); N1b (2-3 LN+; HR 1.90; 95% CI, 1.82-1.99); N2a (4 LN+; HR, 2.19; 95% CI, 2.03-2.37); N2b (5-8 LN+; HR, 2.51; 95% CI, 2.35-2.68); N3 (≥9 LN+; HR, 3.35; 95% CI, 3.04-3.70). By contrast, the AJCC 8E nodal classification system spanned a more limited range of mortality risk: N0 (0 LN; reference); N1 (HR, 1.24; 95% CI, 1.09-1.42); N2 (HR, 1.62; 95% CI, 1.41-1.86); N3 (HR, 1.11; 95% CI, 0.75-1.64). The proposed nodal system was validated for overall survival (log-rank P<0.001) and cause-specific survival (k-sample P<0.001) among 112,153 patients with or without neoadjuvant treatment from the SEER-18 validation cohort. <h3>Conclusion</h3> Number of positive LNs is a dominant predictor of outcomes in patients with NSCLC undergoing surgical resection and nodal evaluation, whereas LN location has more limited independent prognostic information in this context. Thus, nodal count should serve as a backbone for pathologic nodal staging in patients with NSCLC.

Impact of Para-Aortic Lymph Node Count on Survival in Patients with Cervical Cancer and Para-Aortic Lymph Node Involvement Treated with Definitive Radiation Therapy

<h3>Purpose/Objective(s)</h3> Definitive chemoradiation is the standard treatment for loco-regionally advanced cervical cancer. One of the major changes in the 2018 FIGO staging update was the inclusion of para-aortic lymph node (PAN) involvement in a new IIIC2 category. However, the impact of the extent of para-aortic involvement on treatment outcomes remains unclear. This study aims to correlate features of PAN metastases with treatment outcomes in order to inform future treatment strategies for these patients. <h3>Materials/Methods</h3> Electronic medical databases were queried to identify all cervical cancer patients with FDG-avid PAN metastases treated with curative intent using extended field radiotherapy +/- concurrent chemotherapy at our institution between 2004 to 2018. Patients with neuroendocrine histology or distant metastases were excluded. We determined the number of FDG-avid PANs; distance between the highest PAN and the renal vessels or aortic bifurcation; and the size of the largest PAN. Analysis of variance, Kaplan-Meier method, log-rank tests, and Cox proportional hazard tests were used for analysis. <h3>Results</h3> The 5-year OS of the 102 patients in this study was 42% (95% CI, 32-52%), and the 5-year DMFS was 49% (95% CI, 39-59%). The 5-year OS for patients with non-squamous cancers metastatic to the PANs (N=18) vs. patients with squamous cancers metastatic to the PANs (N=84) were 28% and 45%, respectively (<i>P</i> = 0.075). None of the PAN characteristics studied were significantly associated with OS. However, DMFS was strongly associated with the number of FDG-avid PANs; DMFS of patients with <5 or ≥5 PANs were 56% and 17%, respectively (<i>P</i> = 0.0002). PAN size and the distance between the highest PAN and the renal vessels were not significantly correlated with DMFS. On univariate analysis, age (<i>P</i> = 0.12), BMI (<i>P =</i> 0.91), FIGO 1994 stage (<i>P</i> = 0.35), primary lesion size (<i>P</i> = 0.31), or histologic type (<i>P</i> = 0.99) were not significant predictors of PAN count. None of the 3 patients with more than 5 PAN mets from non-squamous cervical cancers survived. For patients with < 5 positive PANs, those with non-squamous cancers (15 patients) had a 5-year OS of 33%, vs. 44% for 77 patients with squamous histology (<i>P</i> = N.S.). On multivariate analysis, PAN count was significantly associated with 5-year DMFS but not OS. <h3>Conclusion</h3> Although the number of FDG+ PANs was correlated with poor DMFS, proximity to the renal vessels and nodal size appear to have less influence on outcome. The presence of both PAN count 5 or higher and adenocarcinoma histology conferred very poor outcomes. Although even patients with extensive PAN metastases are frequently curable with RT, these data suggest that patients with many PAN metastases from non-squamous cervical cancers may benefit from strategies that emphasize systemic treatments.

Characterization of Loss of Prognostic Data with Updated Pathologic Nodal Staging System for p16+ Oropharyngeal Squamous Cell Carcinoma

<h3>Purpose/Objective(s)</h3> Although the AJCC 8^th edition introduced a distinct pathologic nodal staging system for p16+ OPSCC, the removal of multiple factors in the 7^th edition, including nodal size, quantity, extracapsular extension (ECE), and laterality may limit valuable risk stratification and prognostication. This study aimed to characterize whether the simplification of the new staging system resulted in the loss of prognostic value by using the National Cancer Database (NCDB). <h3>Materials/Methods</h3> The NCDB was queried for patients diagnosed with node-positive p16+ OPSCC. Patients without staging information, metastatic disease, who did not receive definitive surgery, had unknown quantity of positive nodes, or had unknown follow-up were excluded. The optimal nodal quantity threshold was explored using a sensitivity analysis with univariable Cox proportional hazards regression. The prognostic impact of nodal size, nodal laterality, ECE, and the previously identified nodal quantity on OS were then assessed using survival analysis with the Kaplan Meier method, univariable, and multivariable Cox proportional hazards regression. <h3>Results</h3> A total of 5,186 patients met the inclusion criteria. On Kaplan Meier analysis, patients with more than four positive lymph nodes had significantly inferior OS (p<0.001; 5-yr OS: 76% vs 90%). Patients with ECE also had inferior outcomes (p<0.001; 5-yr OS: 83% vs 92%). A nodal size of >6 cm was also associated with inferior OS (p<0.001; 5-yr OS: 81% vs 89%). Lastly, patients with contralateral or bilateral nodal involvement also had inferior OS (p<0.001; 5-yr OS: 81% vs 89%). The nodal count threshold of four (p<0.001; HR [95% CI]: 2.75 [2.27-3.33]), as used in the AJCC 8^th edition, was also validated as the optimal prognostic value using the sensitivity analysis, in comparison to thresholds of three (p<0.001; HR [95% CI]: 2.33 [1.94-2.80]) or five (p<0.001; HR [95% CI]: 2.86 [2.33-3.53]). On multivariable Cox regression, having more than four positive nodes (p<0.001; HR [95% CI]: 1.82 [1.47-2.26]), ECE (p<0.001; HR [95% CI]: 1.60 [1.32-1.95]), and a node >6 cm (p<0.001; HR [95% CI]: 1.78 [1.04-3.02]) remained associated with inferior OS. Node laterality was no longer significant (p=0.412). Other factors associated with OS included age, Charlson Deyo score, insurance type, T stage, and lymphovascular invasion (LVSI). <h3>Conclusion</h3> Patients with a nodal size of >6 cm, more than four positive lymph nodes, ECE, or contralateral or bilateral nodal involvement have inferior OS. While AJCC 8^th edition serves to improve pathologic staging criteria, the associated simplifications result in loss of prognostic information in nodal staging. Although all of these factors needn't necessarily be included in the staging system, work evaluating the impact of the updated pathologic nodal staging for p16+ OPSCC prognostication and treatment selection is warranted, particularly given that factors such as ECE do influence adjuvant treatment.

Importance of Arterial Vessel Length for Metastatic Lymph Node Retrieval and Survival in Standardized Left- and Right-Sided Colon Cancer Surgery.

We investigated the localization of lymph node metastases, and the role of arterial vessel and specimen lengths in left- and right-sided colon cancer surgery, for survival. This was a prospective cross-sectional population-based study of specimens from patients who underwent standardized surgical resection for colon cancer in 2012-2015. The mesocolon of the specimens was divided into four sections for pathological analysis of lymph nodes. Multiple linear regression analysis was used to explore the relationship between lymph node counts and patient- and surgery-related factors. For survival analysis, a multivariable Cox regression method was used. A total of 317 patients (160 females) were included. Median (range) age was 74 (30-95) years. Median number of lymph node retrieval was 32 (8-198) and was associated with increased specimen length but not to arterial vessel length. One hundred and thirty-three (42%) patients had lymph node metastases. All patients had these located < 5cm from the tumour. Ten, two, and three specimens had lymph node metastases around the central and peripheral ligation of the ileocolic artery and at the central ligation of the inferior mesenteric artery, respectively. The tumour stages in these specimens were T3-4N2M0-1. No statistically significant survival benefit was associated with longer arterial vessel length (p = 0.429). Neither retrieval of lymph nodes nor statistically significant survival was affected by vessel length in standardized left- and right-sided colon cancer surgery.

Construction of Mobile Internet Financial Risk Cautioning Framework Based on BP Neural Network

With the emergence of the 21st-century global economy, the international financial system faces economic risks. A competitive cautioning model for financial management is required to mitigate risks and losses in the financial sector. The financial losses of the banking industry have been categorized and analyzed using the Internet of Things (IoT) and big data technologies to minimize the economic risk of commercial banks in mobile internet finance (MIF). This article proposes a new financial risk cautioning framework (FRCF) based on the IoT, big data, and back propagation-neural network (BP-NN) to ensure steady growth of MIF in the long term. In this article, a big data technology-based approach for data recognition and mining has been suggested. A BP-NN-based method for risk identification and assessment in MIF is also presented. The BP-NN technique calculates each neural network (NN) layer’s node count, transfer functions, learning rate, and other characteristics. The proposed FRCF has been developed through the proper construction, analysis, and testing of many information samples. A conceptual understanding of the use of IoT, big data, and artificial intelligence (AI) technologies through NN models in the financial industry has been described in the article. The proposed FRCF can predict the MIF risks associated with the MIF lending infrastructure with a 98.2% accuracy.

Node Count as a Quality Indicator in Surgically Treated Mucosal Head and Neck Squamous Cell Cancer.

A yield of ≥18 nodes from neck dissection has been shown to be associated with improved locoregional recurrence rates and survival. We sought to determine factors associated with lymph node yields below this threshold. A retrospective review of patients who underwent neck dissection as part of definitive surgical treatment for mucosal head and neck squamous cell carcinoma (SCC) between January 2015 and December 2018 at an academic tertiary referral center was performed. Patients with a history of prior radiation or neck dissection were excluded. There were 412 neck dissections performed in 323 patients. Specimens containing <18 nodes decreased from 16.2% in 2015-2016 to 7.4% of neck dissections in 2017-2018. The proportion of neck dissections removing <3 levels decreased from 9.1% of neck dissections in 2015-2016 to 4.0% in 2017-2018. Multivariable regression analysis demonstrated that dissection of ≥3 levels (OR=0.2 [0.1-0.4]) and neck dissection in 2017-2018 compared to 2015-2016 (OR=0.4 [0.2-0.8]) were significantly associated with a lower odds of <18 nodes. Stage, site, race, sex, human papillomavirus status, positive nodes, surgeon volume, and pathologist volume were not associated with neck dissection specimens with <18 nodes, after controlling for all other variables. Increased recognition of the importance of node count as a quality indicator, and the extent of neck dissection is associated with increased nodal yield from neck dissection. These data suggest that node count can be used as a quality measure of neck dissection for mucosal SCC. 4 Laryngoscope, 133:2160-2165, 2023.

An Enhanced Software Framework for Improving QoS in IoT

Internet of Things (IoT) and Artificial Intelligence (AI) with its subcomponents are the latest emerging technologies that make our daily lives easier. Quality of Service (QoS) plays a very important role in IoT due to the large number of interconnected nodes. QoS is inversely dependent on the node count, i.e. the increment of nodes causes hampering to QoS, as increasing the number of nodes increases the number of requests to the IoT server. An enhanced framework is strongly needed to control QoS in IoT applications. This study proposes and implements an enhanced framework using Matlab, to control the number of requests. The proposed model can improve QoS parameters like throughput, latency, and packet loss by reducing the number of requests generated by the end nodes without compromising the services to the end user. The results showed that QoS parameters improved in terms of throughput by 5-10%, packet loss by up to 6%, and packet latency by 4%. This model can also be tested in hardware and may provide a better QoS solution.

Sağ kolon tümörlerinde laparoskopik komplet mezokolik eksizyon ve santral vasküler ligasyon öğrenme eğrisi için kümülatif toplam analizi

Purpose: Every procedure, no matter how difficult, has a learning curve. However, no one discusses the learning curve for simple operations. This idea constantly comes up when there is a demanding surgical method that challenges habits. The aim of this study is to use cumulative sum analysis to estimate the learning curve of the demanding laparoscopic complete mesocolic excision+central vascular ligation technique for right sided colon cancer.&#x0D; Materials and Methods: This retrospective study involved patients older than 18 years and with right-sided colon cancer admitted to Ankara University School of Medicine, Department of General Surgery between January 2015 and June 2022. The cumulative sum (CUSUM) chart based on operation duration and quantity of lymph nodes harvested was utilized to determine the learning curve.&#x0D; Results: 53 patients included in this study. CUSUM analysis based on operation duration showed that Surgeon had passed the learning phase and was considered proficient after 21 cases. And the CUSUM analysis based on the lymph nodes harvested revealed that surgeon gained proficiency in 25th case. In terms of demographic, oncological, and operative data, there was no difference between the the groups defined by the phases according to the CUSUM analysis based on both operation duration and lymph node count.&#x0D; Conclusion: Surgeons can become familiar with laparoscopic complete mesocolic excision for right sided colon cancer and perform it after approximately 21 to 25 operations.

376. THE IMPACT OF OVERALL SURVIVAL ON TWO-FIELD OR THREE-FIELD LYMPHADENECTOMY IN MIDDLE AND LOWER THORACIC ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract More than 50% of esophageal cancer cases worldwide occur in China. Squamous cell carcinoma is the main subtype of esophageal cancer in East Asian. The manner of lymphadenectomy during surgery is related to the OS, but the effect of removed lymph node count for middle and lower thoracic esophageal squamous cell carcinoma (ESCC) in China is still controversial. Data were obtained from the Sichuan Cancer Hospital &amp; Institute Esophageal Cancer Case Management Database (SCH-ECCM Database) from Jan. 2010 to Dec. 2017. Patients were divided into two groups: For patients without suspicious tumor-positive cervical lymph nodes, 2-field systematic lymphadenectomy was performed and were belonged 2F group, while patients with suspicious tumor-positive cervical lymph nodes, 3-field systematic lymphadenectomy was performed and were put into 3F group. According to the quartile number of resected lymph nodes during operation. Four subgroups were designed for analysis in 2F group and 3F group, depending on the intensity of the lymphadenectomy. After 60.0 months (95% CI 56.5–63.4) of median follow-up time. The median OS of 2F group patients was 46.9 months (95% CI 39.3–54.5), 3F group was 34.0 months (95% CI 26.1–42.0). The OS at 1, 3, and 5 years were 87%, 57%, and 46% in the 2F group. In the 3F group, the OS rates at 1, 3, and 5 years were 82%, 49%, and 41% (P = 0.029). According to the quartile number of RLNs, there were different survival outcomes in 3F sub-groups, while in the 2F groups, the OS between A/B/C/D group was not significantly different (Fig A &amp; B). ESCC patients with suspicious tumor-positive cervical lymph nodes have significantly worse OS than patients who without tumor-positive cervical lymph nodes. Different lymph nodes number removed in 3F patients could lead the entirely different survival outcomes. However, this still needs further large scale study to verify in China.

594. TOTALLY MINIMALLY INVASIVE 2-STAGE ESOPHAGECTOMY VERSUS HYBRID 2-STAGE ESOPHAGECTOMY. A SINGLE CENTER EXPERIENCE

Abstract Totally minimally invasive 2-stage esophagectomy (TMIE) eliminates the thoracotomy associated with hybrid 2-stage minimally invasive esophagectomy (hybrid-MIE). This has an important role in minimizing post-operative respiratory complications. There is ongoing growing evidence in published literature of improved clinical and oncological outcomes in totally MIE comparing to hybrid MIE, due to enhanced optics and extend of lymphadenectomy as well as to shorter length of hospital stay and surgical trauma associated to thoracoscopy. This is a retrospective analysis of consecutive patients that underwent 2-stage minimally invasive esophagectomy for esophageal and gastro-esophageal junction Siewert type I-II cancers. TMIE combines a laparoscopic and thoracoscopic approach while hybrid-MIE includes laparoscopic open thoracotomic phase. Study included adult patients with no upper age limit (&amp;gt;18 years). All esophagectomies for benign disease, as well as emergency operations were excluded from the study. Primary endpoints were 30- and 90-day mortality rate, anastomotic leak, anastomotic stricture, pulmonary complications, and length of hospital stay. Secondary endpoints were overall survival and progression-free survival rates respectively. During an 8-year-period, 150 patients underwent hybrid-MIE, while 200 underwent TMIE. Operative-time was shorter in the hybrid-MIE group (320 vs 280 min). Anastomotic leak was significantly reduced in the TMIE group comparing to the hybrid-MIE group (2.5% vs 9.5%). Respiratory complications were reduced in the TMIE group (10 vs 25%). Median LOS was similar (7 vs 7.5 days). Median number of resected-lymph nodes was increased in the TMIE group (28 vs 35 lymph nodes). OS survival rate was 60 versus 51 months and PFS was 52 vs 43 months in the TMIE and hybrid-MIE groups respectively. In general, TMIE was associated with moderately lower morbidity compared to hybrid-MIE, but randomized controlled evidence is lacking. The higher anastomotic leakage rate, higher rate of pulmonary complications and lower lymph node count that was found after hybrid-MIE in comparative analysis, indicate that TMIE can significantly improve clinical outcomes of patients undergoing esophagectomy. The findings of this study should be considered carefully by surgeons when moving from hybrid-MIE to TMIE.

299. LEFT THORACOPHRENOTOMY OESOPHAGOGASTRECTOMY AS AN ALTERNATIVE APPROACH IN OESOPHAGEAL CANCER

Abstract The left thoracophrenotomy approach to oesophagectomy-also known as Sweet Oesophagectomy (SO)—for oesophageal cancer is performed by many centres worldwide but seldom used in the UK, owing to concerns over the extent of lymphadenectomy compared with the Ivor-Lewis oesophagectomy (ILO) approach. This study aims to compare the oncological and clinical outcomes following the Sweet approach with ILO. A retrospective, single centre study was conducted, analysing all patient data following the SO approach and ILO for oesophageal cancer between August 2012 and March 2021. Total number offered the Sweet and ILO were 72 and 197 patients respectively. 91.7% vs 80.2%, p = 0.071 were distal tumours. Median node count were 22 and 23 respectively, p = 0.980. The Sweet was associated with 69.4% circumferential, 94.4% proximal and 95.8% distal R0 resections compared with 72.6% (p = 0.365), 98% (p = 0.132) and 96% (p = 0.330) with ILO resection, respectively. Median operative time was 169 vs. 301 minutes for Sweet and ILO respectively, p &amp;lt; 0.001. Overall complication rate was 29.2% with Sweet and 45.7% with ILO, p = 0.015, including, Anastomotic leaks 0 vs. 11, p = 0.041, return to theatre 1 vs. 22, p = 0.04. The 30-day, 90-day and 5-year survival was 100% vs. 99% (p = 0.391), 98.6% vs. 95.9% (p = 0.281) &amp; 51.4% vs. 50.3% (p = 0.869), respectively. The Sweet procedure was associated with comparable oncological efficacy and survival to ILO. Furthermore, was associated with significantly shorter operative time and lower complication rates, therefore should be considered in selected cases. Having a reduced hospital stay and operative time may be more favourable in more frail patients with distal and junctional oesophageal tumours.

593. UPPER MEDIASTINAL LYMPHADENECTOMY IN PRONE POSITION TOTALLY MINIMALLY INVASIVE ESOPHAGECTOMY

Abstract Minimally invasive esophagectomy (MIE) is a challenging procedure associated with high rate of complications and mortality. Routine lymphadenectomy includes 2-field lymphadenectomy for distal esophageal or esophago-gastric junction Siewert I-II cancers. SML refers to extended 2-field lymphadenectomy or total mediastinal lymphadenectomy. The exact benefits of superior mediastinal lymphadenectomy (SML) have long been debated with no clear evidence pertaining to improved outcomes. N=150 consecutive patients underwent totally MIE under a surgical team from September 2016 to September 2020. SML included right paratracheal nodes and lymph nodes along the right recurrent laryngeal nerve throughout its mediastinal route (including the paratracheal-retrocaval compartment) in cases of extended 2-field lymphadenectomy, as well as left paratracheal nodes and lymph nodes along the left recurrent laryngeal nerve during total mediastinal lymphadenectomy. Eligible patients underwent SML during 2-stage or 3-stage MIE. N=20 consecutive cases were identified as eligible according to the inclusion criteria during the study period. 30- and 90- day mortality rates were 0. There were no anastomotic or chyle leaks noted. Pulmonary complications were observed in 16.5% of the patients. There was 1 right recurrent laryngeal nerve palsy noted. Median length of hospital stay was 9 days. Median number of resected lymph nodes was 45 (Range: 37-68), with median SML nodes count being 8 (Range: 2-25). Median follow up was 24 months. The small sample size is immediately recognised as a limiting and influencing factor in the results of this study. However, MIOs with SML may provide some, although not comprehensive, benefit in oncological outcomes without adding any further significant morbidity. Larger studies are needed to assess the role SML can play in improving patient outcomes.

The ICON-A model for direct QBO simulations on GPUs (version icon-cscs:baf28a514)

Abstract. Classical numerical models for the global atmosphere, as used for numerical weather forecasting or climate research, have been developed for conventional central processing unit (CPU) architectures. This hinders the employment of such models on current top-performing supercomputers, which achieve their computing power with hybrid architectures, mostly using graphics processing units (GPUs). Thus also scientific applications of such models are restricted to the lesser computer power of CPUs. Here we present the development of a GPU-enabled version of the ICON atmosphere model (ICON-A), motivated by a research project on the quasi-biennial oscillation (QBO), a global-scale wind oscillation in the equatorial stratosphere that depends on a broad spectrum of atmospheric waves, which originates from tropical deep convection. Resolving the relevant scales, from a few kilometers to the size of the globe, is a formidable computational problem, which can only be realized now on top-performing supercomputers. This motivated porting ICON-A, in the specific configuration needed for the research project, in a first step to the GPU architecture of the Piz Daint computer at the Swiss National Supercomputing Centre and in a second step to the JUWELS Booster computer at the Forschungszentrum Jülich. On Piz Daint, the ported code achieves a single-node GPU vs. CPU speedup factor of 6.4 and allows for global experiments at a horizontal resolution of 5 km on 1024 computing nodes with 1 GPU per node with a turnover of 48 simulated days per day. On JUWELS Booster, the more modern hardware in combination with an upgraded code base allows for simulations at the same resolution on 128 computing nodes with 4 GPUs per node and a turnover of 133 simulated days per day. Additionally, the code still remains functional on CPUs, as is demonstrated by additional experiments on the Levante compute system at the German Climate Computing Center. While the application shows good weak scaling over the tested 16-fold increase in grid size and node count, making also higher resolved global simulations possible, the strong scaling on GPUs is relatively poor, which limits the options to increase turnover with more nodes. Initial experiments demonstrate that the ICON-A model can simulate downward-propagating QBO jets, which are driven by wave–mean flow interaction.

Total Neoadjuvant Treatment for Pancreatic Ductal Adenocarcinoma Is Associated With Limited Lymph Node Yield but Improved Ratio

IntroductionThe lymph node yield (LNY) and lymph node ratio (LNR) of nodal metastases following pancreatoduodenectomy (PD) have been reported as prognostic parameters in patients with pancreatic ductal adenocarcinoma (PDAC). However, they have not been compared in the setting of various neoadjuvant therapy modalities. MethodsA single institutional retrospective study identified 134 patients diagnosed with resectable, BLR- and LA-PDAC who underwent PD at Fox Chase Cancer Center between 2010 and 2019. Patients were categorized based on first-line treatment as follows: surgery first (SF), total neoadjuvant therapy (TNT), and single modality neoadjuvant therapy (SMNT). The histopathological reports of the surgical specimens were examined to obtain LNY and determine the counts of lymph nodes with metastases. Subsequently, LNR was calculated as the number of positive lymph nodes divided by the number of lymph nodes examined. ResultsOverall, 49, 38, 27, 12, and 8 patients underwent SF approach, SMNT, incomplete TNT, induction TNT, and consolidation TNT, respectively. There was no difference in R0 resection and vascular resection between the groups (P = 0.096 and 0.794, respectively). The median counts of LNY were 22, 15, 21, 11.5, and 10, respectively (P < 0.001). The average LNR was 0.16, 0.07, 0.03, 0.02, and 0.02, respectively (P < 0.001). There were statistically significant differences in overall survival in the TNT groups (log-rank test P = 0.030). ConclusionsPDAC patients who undergo the TNT modality exhibit lower LNY and improved LNR compared with the SF approach and SMNT neoadjuvant therapy groups. This is likely explained by the increased treatment response and lymph node obliteration associated with the TNT approach. Our results question the minimal requirement of 11-18 harvested lymph nodes for PD following TNT.

Radikal gastrektomi sonrası eş zamanlı kemoradyoterapi uygulanan lokal ileri evre mide kanserlerinde mide kanseri prognostik indeksinin önemi

Amaç: Radikal gastrektomi sonrası eş zamanlı kemoradyoterapi ile tedavi edilen lokal ileri evre mide kanseri hastalarında albümin ve metastatik lenf nodu sayısının bir kombinasyonu olan yeni mide kanseri prognostik indeksinin önemi araştırılmıştır. Yöntem: Bu retrospektif çalışmamıza Ocak 2014 ile Aralık 2019 tarihleri arasındaki hastalar dahil edilmiştir. Albümin için eşik değer 3.5 g/dL kabul edilirken, metastatik lenf nodu sayısı için ideal eşik değerini tanımlamak amacıyla ‘’receiver operating characteristic’’ eğrisi analizi kullanılmıştır. Bulgular: Çalışmamıza toplam 137 hasta dahil edilmiştir. Albümin 3.5 g/dL (&amp;lt;3.5’e karşılık ≥3.5 g/dL) ve metastatik lenf nodu sayısı için ise eşik değer 5’e göre (&amp;lt;5’e karşılık ≥5) dört olası grup oluşturulmuştur. Grup-1: Albümin ≥3.5 g/dL ve metastatik lenf nodu sayısı &amp;lt;5 Grup-2: Albümin ≥3.5 g/dL ve metastatik lenf nodu sayısı ≥5, Grup- 3: Albümin &amp;lt;3.5 g/dL ve metastatik lenf nodu sayısı &amp;lt;5 ve Grup-4: Albümin &amp;lt;3.5 g/dL ve metastatik lenf nodu sayısı ≥5. Sağ kalım analizlerinde Grup 2 ve Grup 3 arasında anlamlı bir fark bulunmadığı için bu iki grup birleştirilerek mide kanseri prognostik indeksi-2 oluşturulmuştur. Kaplan-Meier eğrilerinden mide kanseri prognostik indeksi-1 ve mide kanseri prognostik indeksi-3 gruplarının sırasıyla progresyonsuz (66.0 aya karşı 16.4 ay; p&amp;lt;0.001) ve genel sağ kalım (66.0 aya karşı 19.5 ay p&amp;lt;0.001) sonuçlarına sahip olduğu belirlenmiştir. Çok değişkenli analiz sonuçları yeni mide kanseri prognostik indeksinin genel (p&amp;lt;0.001) ve progresyonsuz sağ kalım (p=0.05) için bağımsız bir prognostik faktör olduğunu göstermiştir. Sonuç: Çalışmamızdan elde edilen sonuçlar mide kanseri prognostik indeksinin güçlü ve bağımsız bir belirteç olduğunu göstermiştir

Predictive value of NLR and PLR in response to preoperative chemotherapy and prognosis in locally advanced gastric cancer.

PurposePretreatment neutrophil-to-lymphocyte (NLR) and platelet-to-lymphocyte (PLR) ratios are markers of systemic inflammation. In patients with locally advanced gastric cancer (GC), the utility of these ratios in predicting tumor regression grade (TRG) after neoadjuvant chemotherapy (NCT) remains unclear.MethodsThis retrospective study examined 283 locally advanced GC patients who underwent NCT and radical surgery. The receiver operating characteristic (ROC) curve analysis and the Youden index were applied to identify optimal NLR/PLR cutpoints. The Kaplan–Meier method was used to estimate overall survival (OS) and disease-free survival (DFS). Univariate/multivariate analyses were conducted by the logistic regression method.ResultsTRG grade proved significantly worse in patients with high values of both NLR and PLR whether in univariate (OR = 3.457; p = 0.044) or multivariate (OR = 6.876; p = 0.028) analysis. The degree of tumor differentiation was an independent predictive factor for TRG (OR = 2.874; p = 0.037) in multivariate analysis. In the subgroup analyses, NLR predicted OS (p = 0.04) and DFS (p = 0.03) in female patients, whereas PLR was predictive of both OS (p = 0.026) and DFS (p = 0.018) in patients with clinical TNM stage 3 disease and dissected lymph node counts <28. PLR similarly predicted OS in patients <65 years old (p = 0.049), those with positive lymph nodes (p = 0.021), or those with moderate or poorly differentiated tumors (p = 0.049).ConclusionPretreatment NLR and PLR together serve to independently predict TRG after NCT and surgery in patients with locally advanced GC. Screening for patients with high NLR and PLR values may allow them to benefit upfront from alternatives to NCT.

Design of a novel micro‐Zone adaptive Energy‐Trust evaluation Active On‐Demand Vector protocol to optimize communication in challenging and attacked mobile network

SummaryHigh congestion, mobility, and energy restrictions are the critical challenges to mobile networks. The conventional routing protocols are unable to ensure effective and reliable communication in such dynamic and unpredictable situations. In this paper, a novel micro‐Zone adaptive Energy‐Trust evaluation Active On‐Demand Vector (mZ‐ETAODV) protocol is designed to provide routing solutions in extreme conditions. In this work, the complete network is divided into smaller zones of nxn. The extreme zone position‐based evaluation is conducted to handle the stability and to identify the next intermediate node. The zone‐covered neighbors are further computed under energy and trust measures to identify the most reliable neighbor. The proposed protocol is simulated under high mobility, congestion and man‐in‐middle attack situations. The analytical observations are recorded in terms of Packet Delivery Ratio (PDR) ratio, energy consumption, delay and communication loss parameters. The comparative results are generated against AODV, SAODV, PSAODV, PDS‐AODV, NVS‐AODV, iNVS‐AODV, Tripathy et al., DFMCRP, FBSSR, MBDP‐AODV, AGHA, and Singh et al. protocols. The experimentation is conducted in a highly challenging mobile network with high congestion, high mobility, energy restriction, existence of blackhole, grayhole, DDOS, and mixed attacks. These attacks are performed with 0% to 10% density, and analysis is conducted against PDR ratio, communication delay, route switching, dead node count, remaining energy, and attack detection rate measures. The analysis results identified that the proposed protocol reduced the communication delay and energy consumption and achieved significant gain in attack detection rate, network life and PDR ratio.