Total Node Count Research Articles

The Relationship Between the Resected Colon Length and the Number of Lymph Nodes in Colorectal Cancer: A Retrospective Cohort Study

Objective: The prognostic factors that are important for colorectal cancer are the pathological grade of the tumor and the existence of lymph node involvement. Currently, the curative treatment option is resection of the tumor with adequate length and margin along with complete dissection of lymph nodes draining the site of resection. Our study investigated into retrieving adequate lymph nodes for accurate staging as well as the relationship between lymph nodes and colon and rectum specimen length. Methods: This retrospective cross-sectional study examined the correlation between resected colon length and lymph node count in people with colorectal cancer diagnosed between January 2010 and June 2018. We defined a cutoff value for the segment length to be resected to allow adequate staging of the tumor. Furthermore, we examined the relationship between the resected segment lengths and survival. Results: Of the patients who were included in this study, 211 were men and 169 were women. The mean resected colon length was 26.47±17.09 cm and the mean dissected lymph node count was 29.05±20.84. There was a positive correlation between specimen length and total lymph node count as well as specimen length and the existence of reactive lymph nodes that were statistically significant (r=0.319, p=0.001; r=0.312, p=0.001, respectively). In our study, tumor localization was described in three regions: the right colon, left colon and rectum. The mean right colon region specimen length was 28.8±15.5 cm, while it was 22.0±11.0 cm for the left colon region, and 21.7±10.6 cm for the rectum region. The 5-year overall survival rate was 53.2%, whereas the 5-year disease-specific survival rate was 58.2%. Conclusion: The mean specimen length to achieve the cutoff value for adequate lymph node retrieval (least 12 lymph nodes) was 16 cm in our study (ROC curve, AUC=0.689±0.05, p=0.001). The resected colon length and the number of retrieved lymph nodes were positively correlated in our study. Based on this confirmation, a cutoff value of 16 cm was calculated to achieve an adequate segment length to be resected.

An enhanced energy efficient protocol for large-scale IoT-based heterogeneous WSNs

There is increasing attention, recently, to optimizing energy consumption in IoT-based large-scale networks. Extending the lifetime of battery-powered nodes is a key challenge in such systems and their various application scenarios. This paper proposes a new zone-based and event-driven protocol for saving energy in large-scale heterogeneous WSNs called TESEES (Threshold Enabled Scalable and Energy Efficient Scheme). The proposed protocol is designed to support network scenarios deploying higher levels of heterogeneity with more than three types of sensor nodes (i.e., four, five, and more). TESEES is a reactive version of the proactive SEES protocol, in which we leverage a novel state-of-the-art thresholding model on the zone-based hierarchical deployments of heterogeneous nodes to regulate the data reporting process, avoiding unnecessary frequent data transmission and reducing the amount of energy dissipation of the sensing nodes and the entire system. With this model, we present a general technique for formulating distinct thresholds for network nodes in each established zone. This mechanism allows for individually configuring the nodes with transmission settings tailored to their respective roles, independent of the heterogeneity levels, total node count, or initial energy. This approach ensures that each node operates optimally within the network. In addition, we present an improved hybrid TMCCT (Threshold-based Minimum Cost Cross-layer Transmission) algorithm that operates at the node level and ensures effective data transmission control by considering current sensor values, heterogeneous event thresholds, and previous data records. Instead of periodical data transmission, this hybridization mechanism, integrated with a grid of energy-harvesting relay nodes, keeps the zone member nodes in the energy-saving mode for maximum time and allows for reactive data transmission only when necessary. This results in a reduced data-reporting frequency, less traffic load, minimized energy consumption, and thus a greater extension of the network’s lifetime. Moreover, unlike the traditional cluster-head election in the weighted probability-based protocols, TESEES relies on an efficient mechanism for zone aggregators’ election that runs at the zone level in multiple stages and employs various static and dynamic parameters based on their generated weights of importance. This leads to selecting the best candidate nodes for the aggregation task and, hence, fairly rotating the role among the zones’ alive nodes. The simulation results show significant improvements in the total energy saving, the lifetime extension, and the transmitted data reduction, reaching 29%, 68%, and 26% respectively, compared to the traditional SEES protocol. Also, the average energy consumption per single round has decreased by 36%.

The value of inflammatory indexes in colorectal cancers

In recent years, a relationship has been established between inflammatory indexes and the prognosis of many cancers. Although there are many studies investigating their relationship with colorectal cancers (CRC), there is a serious difference between the results in the related literature. The present study aimed to share our own experience with inflammatory indexes in CRC patients. Patients with a diagnosis of CRC who underwent surgery between January 2019 and June 2022 were retrospectively scanned. Exclusion criteria were as follows; being in a septic state before surgery, accompanying hematological disease, receiving neoadjuvant chemotherapy/radiotherapy, being diagnosed with recurrent CRC, undergoing emergency surgery, receiving immunosuppressive or anti-inflammatory treatment. Therefore, the study was conducted with 52 patients. Demographic information, tumor localization, stages and pathology data of the patients were examined. The relationship between these variables and the systemic immune-inflammation index (SII), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) was investigated. A significant correlation was found between pathological T stages and SII (p=0.008), NLR (p<0.001) and PLR (p=0.035). No correlation was found between inflammatory indexes and Age, Tumor Diameter, N Stage, Total Lymph Node Count, Metastatic Lymph Node Count. In our study, inflammatory indexes were found to be associated only with the T stage. Considering our results together with the variable results in the literature, more evidence is needed for the safe and active use of SII, NLR and PLR as markers of colorectal cancers.

Photonic Spiking Neural Networks with Highly Efficient Training Protocols for Ultrafast Neuromorphic Computing Systems

Photonic technologies offer great prospects for novel, ultrafast, energy-efficient, and hardware-friendly neuromorphic (brain-like) computing platforms. Moreover, neuromorphic photonic approaches based on ubiquitous, technology-mature, and low-cost vertical-cavity surface-emitting lasers (VCSELs) (devices found in fiber-optic transmitters, mobile phones, and automotive sensors) are of particular interest. Given that VCSELs have shown the ability to realize neuronal optical spiking responses (at ultrafast GHz rates), their use in spike-based information-processing systems has been proposed. In this study, spiking neural network (SNN) operation, based on a hardware-friendly photonic system of just one VCSEL, is reported alongside a novel binary weight “significance” training scheme that fully capitalizes on the discrete nature of the optical spikes used by the SNN to process input information. The VCSEL-based photonic SNN was tested with a highly complex multivariate classification task (MADELON) before its performance was compared using a traditional least-squares training method and an alternative novel binary weighting scheme. Excellent classification accuracies of >94% were achieved by both training methods, exceeding the benchmark performance of the dataset in a fraction of the processing time. The newly reported training scheme also dramatically reduces the training set size requirements and the number of trained nodes (≤1% of the total network node count). This VCSEL-based photonic SNN, in combination with the reported “significance” weighting scheme, therefore grants ultrafast spike-based optical processing highly reduced training requirements and hardware complexity for potential application in future neuromorphic systems and artificial intelligence applications.

OGC P43 Oncological outcomes following the introduction of laparoscopic gastric mobilisation during Ivor Lewis Oesophagogastrectomy within a regional Scottish centre

Abstract Background Ivor Lewis Oesophagogastrectomy (ILO) is a potentially curative but highly morbid surgery. Minimally invasive techniques by comparison have demonstrated improved post-operative outcomes for patients. Hybrid laparoscopic gastric mobilisation (LGM) combined with an open right thoracotomy was introduced in our centre in 2019. This study assessed oncological outcomes between ILO with LGM and a fully open ILO, following this local change in operative technique. Methods This was a retrospective study of patients undergoing ILO at a single tertiary unit over a 5-year period (2017–2021). All patients undergoing open ILO were compared with those who had ILO with LGM. Resected lymph node count was used as a marker for oncological outcomes and median length of hospital stay a marker for post-operative outcomes. Results During the study period, 42 patients had open ILO and 32 had ILO with LGM. Patient demographics were similar between groups, with the majority receiving neoadjuvant chemotherapy (Open ILO 92.9% vs LGM 96.9%, p=0.629). Following local introduction of LGM in 2019, it immediately became the predominant method of gastric mobilisation during ILO (58% cases in 2019; 100% cases in 2020; 73% cases in 2021). Median total lymph node count resected was similar between LGM 17(15–25) vs open ILO 18 (16–24), p=0.643. Overall, length of stay was shorter in those having LGM compared to open (16 (11–21) vs 18 (11–36)), although this did not reach statistical significance (p=0.129). Conclusions Introduction of a hybrid minimally invasive technique for oesophagogastrectomy within our regional centre, has been associated with similar oncological outcomes to the traditional open approach. Further evaluation is required to ascertain the potential patient benefits of a LGM on post-operative outcomes within our patient cohort.

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.

Sentinel lymph node biopsy compared with systematic lymphadenectomy in patients with uterine carcinosarcoma (536)

<b>Objectives:</b> To assess survival among patients with newly diagnosed uterine carcinosarcoma undergoing sentinel lymph node biopsy (SLN) alone and those undergoing systematic lymphadenectomy (LND). <b>Methods:</b> We identified all patients with newly diagnosed uterine carcinosarcoma who underwent primary surgical management at our institution from January 1996 to December 2019. Patients with gross extrauterine disease of any type were excluded. The SLN cohort underwent SLN biopsy alone, with bilateral SLNs identified. The systematic LND cohort did not undergo SLN biopsy. Progression-free survival (PFS) and overall survival (OS) were defined from the date of surgery to the event. Appropriate statistical testing was performed. <b>Results:</b> We identified 99 SLN and 100 LND patients. Median age and BMI were not different between the groups. Minimally invasive surgery was the approach in 56 (56.6%) SLN (56.6%) and 47 (47%) LND patients (p=0.2). There was no significant difference between cohorts with respect to the degree of myoinvasion (<50%, >50%), presence of lymphovascular space invasion (LVSI), stage, or positive washings. The median total node count was four (range: 1-13) for SLN and 19 (range: 2-50) for LN (p<0.001). Nodal metastasis was noted in 26 (26%) SLN and 21 (21%) LND (p=0.4). Postoperative therapy was given to 91 (92%) SLN and 87 (87%) LND (p=0.3). The type of postoperative therapy administered was as follows: none in eight (8%) SLN and 14 (14%) LND; chemotherapy with or without radiation (RT) in 86 (87%) SLN and 71 (71%) LND; RT alone in five (5%) SLN and 15 (15%) LND (p=0.02). Median follow-up was 51.3 months (range: 0.9-211.1) for the SLN cohort compared with 40.8 months (range: 0.5-269.1) for the LND cohort (p=0.3). The 4-year PFS was 62.4% (SE 5.3%) for SLN and 47.7% (SE 5.5%) for LND (p=0.07). The 4-year OS was 72.4% (SE 4.9%) for SLN and 62.2% (SE 4.2%) for LND (p=0.2). There was no difference in PFS or OS when adjusted for the type of postoperative therapy (chemotherapy with or without RT vs none/RT). An isolated nodal recurrence occurred in two (2%) SLN and four (4%) LND patients (p=0.2). <b>Conclusions:</b> There is no difference in PFS or OS among patients who have uterine carcinosarcoma and undergo SLN biopsy versus systematic LND. SLN biopsy adequately detects the presence of nodal metastasis in these patients. SLN biopsy alone does not compromise oncologic outcomes, and systematic LND is unnecessary in the setting of successful bilateral SLN mapping.

Importance of HALP Score in Breast Cancer and its Diagnostic Value in Predicting Axillary Lymph Node Status.

To determine the diagnostic value of the haemoglobin, albumin, lymphocyte, and platelet (HALP) score in predicting axillary lymph node (ALN) involvement. Observational study. Department of General Surgery, Balıkesir University and Mersin City Hospital, Turkey from January 2016-December 2021. Included in the study were 307 patients who underwent surgical treatment for breast cancer. HALP values were calculated by multiplying the haemoglobin, albumin, and lymphocyte values and dividing the resulting value by the platelet number. The patients were divided in two groups, being those with low HALP (Group 1) and high HALP (Group 2) scores. We examined the potential of the HALP score for the prediction of ALN involvement. Group 1 had 65 patients and the Group 2 had 242 patients. At the cut-off point, a HALP score of <29.01 predicted the presence of axillary involvement with a sensitivity of 84.33% and a specificity of 26.1%. The sentinel lymph node sampling rate was similar in both groups (12.3% vs. 16.9% p=0.365). The presence of positive lymph nodes in the axilla was higher in group 1 (67.7% vs. 53.3% p=0.038). There was no correlation between HALP score, and the metastatic lymph node and total lymph node count. The use of HALP score alone for the prediction of axillary lymph node positivity in patients with breast cancer is not advised. In the present study, a low HALP score was associated with aggressive tumour activity, such as advanced tumour and axillary lymph node positivity. Breast cancer, Axillary lymph node involvement, Immunity, Nutrition.

Sentinel lymph node biopsy alone compared to systematic lymphadenectomy in patients with uterine carcinosarcoma

ObjectiveTo assess survival among patients diagnosed with uterine carcinosarcoma (CS) who underwent sentinel lymph node (SLN) biopsy alone vs. systematic lymph node dissection (LND). MethodsWe identified newly diagnosed CS patients who underwent primary surgical management from January 1996–December 2019. The SLN cohort underwent SLN biopsy alone with bilateral SLNs identified. The systematic LND cohort did not undergo SLN biopsy. ResultsNinety-nine patients underwent SLN biopsy, and 100 patients underwent systematic LND. There was no difference by age, stage, body mass index, myoinvasion (<50%, ≥50%), lymphovascular space invasion, or positive washings. Eighty-five SLN (85.9%) and 15 LND (15%) underwent minimally invasive surgery (P < 0.001). The median total node count was four (range, 1–13) for SLN and 19 (range, 2–50) for LND (P < 0.001). Nodal metastasis occurred in 23 (23.2%) SLN and in 22 (22%) LND (P = 0.4). Postoperative therapy was administered to 85 (85.9%) SLN and 71 (71%) LND (P = 0.02). Median follow-up was 33 months (range, 1–205) for SLN and 55.3 months (range, 1–269) for LND (P = 0.001). The three-year progression-free survival (PFS) was 62.9% (SE 5.2%) for SLN and 52.3% (SE 5.3%) for LND (P = 0.13). The three-year overall survival (OS) was 72.1% (SE 5.1%) for SLN and 71.6% (SE 4.6%) for LND (P = 0.68). An isolated nodal recurrence occurred in two (2%) SLN and four (4%) LND (P = 0.26). ConclusionsThere is no difference in PFS or OS among CS patients who undergo SLN biopsy vs. systematic LND. SLN biopsy detects nodal metastasis without compromising oncologic outcomes.

Abstract PO-228: Racial disparities and the impact on recurrence and survival in non-metastatic colon cancer patients undergoing colectomy at a comprehensive cancer center

Abstract Introduction/Purpose: Colorectal cancer has worse outcomes among Black patients; however, few studies have evaluated differences in recurrence rates after surgery. Our goal was to compare recurrence between Black and white patients with colon cancer treated at a comprehensive cancer center with a standardized quality of care. Methods: A retrospective review of Black and white patients with Stage 0-III colon cancer undergoing surgical resection from 2006-2018 was conducted. Patients with neoadjuvant therapy, adjuvant radiation, and missing median family income or body mass index data were excluded. Demographic and clinical data were collected and compared between the groups. Median family income was estimated using patients' zip codes and Census data. Freedom from Recurrence (FFR) was the primary endpoint with an event defined as colon cancer recurrence. A Kaplan-Meier curve evaluated differences between the racial groups with a log-rank test to assess significance. A multivariable analysis using Cox proportional hazards was conducted, and a p value of &amp;lt;0.05 was considered significant. Results: Two thousand and sixty-one patients were included with 1912 white (93%) and 149 (7%) Black patients. Black patients had a median age of 61 compared with 65 in the white cohort (p=0.003) and had a higher median BMI prior to colectomy (p=0.01). Most had right-sided tumors in both groups (58% for Black and 50% for white patients; p=0.13). About 8% of Black patients had Medicaid insurance compared with 2% of white patients (p=&amp;lt;0.005), and Black patients had a lower estimated median family income (p=&amp;lt;0.005). On surgical pathology, more Black patients had node-positive disease (44% for Black and 33% for white patients; p=0.009) and received adjuvant chemotherapy (48% for Black and 37% for white patients; p=0.006). More Black patients underwent open colectomies (39% and 28% respectively, p=0.02). To assess resection quality, 5 white and 0 Black patients had positive margins, and the median total lymph node count was 25 for Black versus 23 for white patients (p=0.04). Few patients in each group had a colectomy with less than 12 lymph nodes resected (1% for Black and 4% for white patients; p=0.17). The survival analysis showed that white patients had a higher FFR compared to Black patients (p=0.005). However, only T4 classification (hazard ratio 2.03, confidence interval 1.52-2.71; p=&amp;lt;0.001) and node-positive disease (hazard ratio 2.88, confidence interval 2.20-3.79; p=&amp;lt;0.001) correlated with lower FFR on multivariable analysis. Race was not significantly correlated (hazard ratio of 1.47, confidence interval 0.97-2.23; p=0.07). Conclusion: We found significant differences in clinical and tumor characteristics between Black and white colon cancer patients who underwent resection consistent with more advanced presentation in Black patients. While Black patients were found to have a lower FFR, after controlling for other factors, Black and white patients had similar stage specific survival when treated at this comprehensive cancer center. Citation Format: Hannah M. Thompson, Jonathan B. Yuval, Anisha Luthra, Fan Wu, Tolulope Iwayemi, Iris H. Wei, Emmanouil P. Pappou, J. Joshua Smith, Garrett M. Nash, Julio Garcia-Aguilar, Francisco Sanchez-Vega. Racial disparities and the impact on recurrence and survival in non-metastatic colon cancer patients undergoing colectomy at a comprehensive cancer center [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-228.

Prognostic Value of Lymph Node Characteristics in Patients with Cervical Cancer Treated with Radical Hysterectomy.

ObjectiveThis study evaluated the prognostic value of various lymph node (LN) characteristics, including the lymph node ratio (LNR), in patients with cervical cancer treated with radical hysterectomy.MethodsIn this retrospective study, 260 patients with cervical cancer who had undergone radical hysterectomy with pelvic or paraaortic lymphadenectomies were included. LN characteristics related to several LN statuses included total LN counts, LN metastasis, total positive LN counts, LNR, and levels of lymphadenectomy. LNR was defined as the number of metastatic LNs divided by the total number of LNs harvested. Univariate and multivariate analyses for disease-free survival (DFS) and overall survival (OS) were performed using the clinicopathological and LN characteristics.ResultsBased on receiver-operating characteristics curve analysis, the cut-off value of LNR was 0.0625. Multivariate analysis revealed that high LNR was significantly related to tumor recurrence (hazard ratio [HR], 5.182; 95% confidence interval [CI], 2.424–11.075; p < 0.0001). After adjusting for clinicopathological factors, LNR was also independent prognostic factor for predicting tumor recurrence (HR, 5.930; 95% CI, 2.114–16.634; p = 0.0007). However, total retrieved LN counts and level of lymphadenectomy were not associated with survival outcomes.ConclusionLNR may be a prognostic biomarker for predicting disease recurrence in cervical cancer treated with radical hysterectomy.

Influence of colonic mesenteric area on the number of lymph node retrieval for colon cancer: a prospective cohort study.

The minimum harvested 12 lymph nodes (LNs) is regarded as the limit for accurate staging of nodal status in colorectal cancer patients. Besides the association of the lengths of resected intestinal segments and vascular pedicles, the mesocolic mesenteric area's impact on LN count has not been studied. We aimed to evaluate the associations between metric variables, including the mesocolic mesentery area on the nodal harvest. All consecutive patients who underwent elective colectomy with a curative intention for colon adenocarcinoma were prospectively included. The metric variables included the lengths of resected intestinal segments, vascular pedicle, and colonic mesenteric area. The variables influencing the LN count and the correlation between the total LN count and the specimens' relevant metric measurements were analyzed. There were 46 patients with a median age of 64 years. The median count for total LNs was 22, and the LN positivity was 59.2%. There was an inadequate LN yield (<12) in 3 patients (6.1%). No significant associations were found between the adequacy of nodal harvest and the demographic, clinical, and tumoral features (P>0.05). There were significant positive correlations between total LN number and length of vascular pedicle and mesenteric area (r=0.576, P<0.001 and r=0.566, P<0.001). The length of the vascular pedicle and mesenteric area were significantly correlated with total LN counts. Although there was no significant impact on the length of resected segments, the colonic mesenteric area can be used alone as a measure for the assessment of the nodal yield in colon cancer.

Impact of perioperative chemotherapy on postoperative morbidity after gastrectomy for gastric cancer

IntroductionThe use of perioperative chemotherapy (CT) in patients with advanced gastric carcinoma increases their overall survival. This therapy may also increase the number of patients with R0 resection. Potential drawbacks of this therapy, besides its toxicity, include increased surgical morbidity. MethodsWe retrospectively evaluated the records of patients undergoing gastrectomy with curative intent, for carcinoma, at our institution between January 2009 and August 2018. They were divided into two groups: direct surgery (SURG) and perioperative CT (CHEMO). Patients with other neoadjuvant therapies and cardia Siewert I and II carcinomas were excluded.The primary objective was to evaluate the impact of perioperative CT on surgical morbidity. As secondary objectives, resection radicality and total lymph node count were compared between the two groups. ResultsA total of 307 patients (97 direct surgery and 210 perioperative CT) were evaluated. Median age was 67 years old.The overall major surgical morbidity (Clavien-Dindo 3–5) was 10.6% in the CHEMO group and 12.4 in the SURG group (p=0.643).There was no statistically significant difference between the surgical radicality (R0 98% in the SURG group vs 97.5% CHEMO group (p=0.865). There was an increase in the total number of lymph nodes retrieved in the specimen in the CHEMO group (25 vs 22, p=0.001), a difference that was not maintained in the subgroup analysis as a function of the surgery performed. ConclusionsPerioperative CT in gastric carcinoma does not increase surgical morbidity, surgical radicality and total lymph node count.

O30: EVALUATION OF AXILLARY LYMPH NODE METASTATIC BURDEN BY PREOPERATIVE ULTRASOUND

Abstract Introduction Sentinel lymph node biopsy (SLNB) is the gold standard for determining axillary nodal status. There is growing interest in using preoperative axillary ultrasound (AUS) as a non-invasive means of assessing the axilla. However, AUS has limited sensitivity and is subject to operator dependency. This study aimed to quantify axillary nodal burden in preoperative AUS. Method This retrospective study used an institutional database of all primary invasive breast carcinomas from 2006–2019. Those with pathologically proven axillary metastatic disease were included. Patients were considered in two groups, low nodal burden/LNB(1-2LN) and high nodal burden/HNB(≥3LN) based on total positive lymph node count(SLNB+ALND). Preoperative AUS reports were assessed to determine those suspicious for axillary metastasis. Result Of the 347 patients (n=349 axillae), 77.9% had LNB and 22.1% had HNB. In patients with LNB, 228(83.8%) had a normal AUS versus 44(16.2%) suspicious AUS. In those with HNB 60(77.9%) had normal AUS findings versus 17(22.1%) suspicious findings. On multivariate analysis Nottingham Grade-3 was associated with suspicious AUS findings (p=0.02). However, receptor status, SLN macro-metastasis and extra-nodal extension were not associated with abnormal AUS. Conclusion As the surgical approach to the axilla becomes increasingly conservative, detection of axillary involvement by non-invasive means is an area of increasing research. In this cohort, AUS did not reliably identify patients with axillary metastasis. These results highlight the challenges in accurately assessing the axilla using preoperative AUS, which may result in axillary undertreatment if used as an alternative to surgical staging. Take-home message As the surgical approach to the axilla becomes increasingly conservative, detection of axillary involvement by non-invasive means is an area of increasing research. This study highlights the challenges in accurately assessing the axilla using preoperative AUS, which may result in axillary undertreatment if used as an alternative to surgical staging.

A greater lymph node yield is required during pathological examination in microsatellite instability-high gastric cancer

BackgroundThe impact of microsatellite status on lymph node (LN) yield during lymphadenectomy and pathological examination has never been assessed in gastric cancer (GC). In this study, we aimed to appraise the association between microsatellite instability-high (MSI-H) and LN yield after curative gastrectomy.MethodsWe retrospectively analyzed 1757 patients with GC undergoing curative gastrectomy and divided them into two groups: MSI-H (n = 185(10.5%)) and microsatellite stability (MSS) (n = 1572(89.5%)), using a five-Bethesda-marker (NR-24, BAT-25, BAT-26, CAT-25, MONO-27) panel. The median LN count and the percentage of specimens with a minimum of 16 LNs (adequate LN ratio) were compared between the two groups. The log odds (LODDS) of positive LN count (PLNC) to negative LN count (NLNC) and the target LN examined threshold (TLNT(x%)) were calculated in both groups.ResultsStatistically significant differences were found in the median LN count between MSI-H and MSS groups for the complete cohort (30 vs. 28, p = 0.031), for patients undergoing distal gastrectomy (DG) (30 vs. 27, p = 0.002), for stage II patients undergoing DG (34 vs. 28, p = 0.005), and for LN-negative patients undergoing DG (28 vs. 24, p = 0.002). MSI-H was an independent factor for higher total LN count in patients undergoing DG (p = 0.011), but it was not statistically correlated to the adequate LN ratio. Statistically significant differences in PLNC, NLNC and LODDS were found between MSI-H GC and MSS GC (all p < 0.001). The TLNT(90%) for MSI-H and MSS groups were 31 and 25, respectively. TLNT(X%) of MSI-H GC was always higher than that of MSS GC regardless of the given value of X%.ConclusionsMSI-H was associated with higher LN yield in patients undergoing gastrectomy for GC. Although MSI-H did not affect the adequacy of LN harvest, we speculate that a greater lymph node yield is required during pathological examination in MSI-H GC.

Flexible annotation atlas of the mouse brain: combining and dividing brain structures of the Allen Brain Atlas while maintaining anatomical hierarchy

A brain atlas is necessary for analyzing structure and function in neuroimaging research. Although various annotation volumes (AVs) for the mouse brain have been proposed, it is common in magnetic resonance imaging (MRI) of the mouse brain that regions-of-interest (ROIs) for brain structures (nodes) are created arbitrarily according to each researcher’s necessity, leading to inconsistent ROIs among studies. One reason for such a situation is the fact that earlier AVs were fixed, i.e. combination and division of nodes were not implemented. This report presents a pipeline for constructing a flexible annotation atlas (FAA) of the mouse brain by leveraging public resources of the Allen Institute for Brain Science on brain structure, gene expression, and axonal projection. A mere two-step procedure with user-specified, text-based information and Python codes constructs FAA with nodes which can be combined or divided objectively while maintaining anatomical hierarchy of brain structures. Four FAAs with total node count of 4, 101, 866, and 1381 were demonstrated. Unique characteristics of FAA realized analysis of resting-state functional connectivity (FC) across the anatomical hierarchy and among cortical layers, which were thin but large brain structures. FAA can improve the consistency of whole brain ROI definition among laboratories by fulfilling various requests from researchers with its flexibility and reproducibility.

The Number of Sentinel Lymph Nodes Could be Optimized by Adjusting the Injection Dose

Background: The optimal number of sentinel lymph nodes (SLNs) to be removed is controversial based on the false negative rate and prognosis. We investigated factors related to the number of SLNs and the possibility of optimizing the number of SLNs. Methods: We retrospectively reviewed 167 cases in which 0.3 or 0.5 ml of ferucarbotran was sub-dermally injected without massage from July 2016 to November 2018. Sentinel lymph node biopsy (SNB) was conducted using both radioisotope (RI) and superparamagnetic iron oxide (SPIO). The removed nodes with a value of ?0.5 ?T on a magnetometer were considered to be SLNs (SPIO nodes). The total SPIO node count in each case was calculated. Results: There was a significant correlation between the number of SPIO nodes and total count of SPIO nodes (rs=0.821, p&lt;0.0001). With RI and SPIO methods, the average number of removed nodes in the age?75 years and BMI?25 subgroups was significantly lower than that in the age&lt;75 years and BMI&lt;25 subgroups. The number of SPIO nodes was significantly influenced by the injected dose. The average number of SPIO nodes in the age ?75 years and BMI?25 subgroups after injection of 0.5 ml was almost the same as that of the age &lt;75 years and BMI&lt;25 subgroups after injection of 0.3 ml.Conclusion: Obesity and old age seemed to be associated with slow lymphatic flow; however, increasing the dose increased the number of SPIO nodes. Thus, optimization of the number of SLNs seems possible.

Proposed Modification of Staging for Distal Cholangioncarcinoma on the Basis of the 8th Edition of the American Joint Committee on Cancer Staging System

Introduction: We validated 7th and 8th AJCC staging system. Second, we tried to find the optimal value for T category, total lymph node count (TLNC), positive lymph node count (PLNC) and lymph node ratio (LNR). Finally, comparison of performance by various staging models was performed. Method: We retrospectively reviewed 251 patients who underwent surgery for DCC at 4 centers. To determine optimal cutoff value, univariate and multivariate Cox regression analyses were used and χ2 score of each values were compared. To compare the predictive superiority of various staging models, Akaike information criterion (AIC), Bayesian information criterion (BIC), AIC correction (AICc), and Harrells C-statistic were calculated. Results: When applying the optimal cut off value for T category, the categories are classified as follows and referred to as 'revised T category': T1 (< 5mm), T2 (5-10mm) and T3(>10mm). As to N category, PLNC is divided into N (0), N (1-2) and N (≥ 3). LNR were divided into 3 groups (0, >0 to < 0.1 and ≥0.1). In multivariate analysis, age (P = 0.003), TLNC (P = 0.033), revised T(LNR)M staging (P < 0.001) were identified as independent factor for OSR. The predictive performance of revised T (LNR) M staging (AIC:1288.925, BIC 1303.377, AICc 1291.52 and Harrell's C statics 0.667) was superior to other staging system. Conclusions: A modified staging system consisting of revised T category and LNR predicted better overall survival of DCC than AJCC 7th and AJCC 8th editions.

Impact of perioperative chemotherapy on postoperative morbidity after gastrectomy for gastric cancer

IntroductionThe use of perioperative chemotherapy (CT) in patients with advanced gastric carcinoma increases their overall survival. This therapy may also increase the number of patients with R0 resection. Potential drawbacks of this therapy, besides its toxicity, include increased surgical morbidity. MethodsWe retrospectively evaluated the records of patients undergoing gastrectomy with curative intent, for carcinoma, at our institution between January 2009 and August 2018. They were divided into two groups: direct surgery (SURG) and perioperative CT (CHEMO). Patients with other neoadjuvant therapies and cardia Siewert I and II carcinomas were excluded.The primary objective was to evaluate the impact of perioperative CT on surgical morbidity. As secondary objectives, resection radicality and total lymph node count were compared between the two groups. ResultsA total of 307 patients (97 direct surgery and 210 perioperative CT) were evaluated. Median age was 67 years old.The overall major surgical morbidity (Clavien-Dindo 3–5) was 10.6% in the CHEMO group and 12.4 in the SURG group (p=0.643).There was no statistically significant difference between the surgical radicality (R0 98% in the SURG group vs 97.5% CHEMO group (p=0.865). There was an increase in the total number of lymph nodes retrieved in the specimen in the CHEMO group (25 vs 22, p=0.001), a difference that was not maintained in the subgroup analysis as a function of the surgery performed. ConclusionsPerioperative CT in gastric carcinoma does not increase surgical morbidity, surgical radicality and total lymph node count.

Abstract 525: Adult Inducible Deletion of Endothelial Hypoxia-inducible Factor-2α Exaggerates Myocardial Infarction Induced Heart Failure and Cardiac Microvascular Barrier Dysfunction

Background: Myocardial ischemia occurs during myocardial infarction results in the stabilization of Hypoxia-inducible factors (HIFs). Hif2α expresses profoundly in vascular endothelial cells (EC), and its embryonic deletion increases vessel permeability. It has been shown that HIF2a is protective from renal and pulmonary injury. However, the direct role of ecHIF2α in ischemia heart disease is unknown. We hypothesized that ecHIF2a expression in response to myocardial infarction (MI) protects cardiac barrier dysfunction and against heart failure. Methods and Results: We generated the Inducible endothelial-specific knockout mice (ecHIF2a -/- ) by crossing Hif2a flox/flox mice with Cre ERT2 mice under the VE-cadherin promoter. Followed with MI, ecHIF2a -/- mice displayed worsened cardiac function determined by echocardiography, and they had increased mortality as compared to the controls. In vitro, we used primary mouse cardiac microvascular endothelial cells (mCMVEC) from ecHIF2a -/- mouse hearts. We found that under hypoxia condition or 1mM Dimethyloxalylglycine treatment, the deficiency of HIF2a in the mCMVEC increased endothelial permeability determined by trans-endothelial electrical resistance. The knocking down of HIF2a in HUVECs induced by a HIF2a siRNA led to impaired tube formation accessed by the significant reduction in total node counts, junctions, meshes, and full tube length compared to control-siRNA treated cells. HIF2α deletion and hypoxia both reduced endothelial cell migration, and interestingly, the retarded HIF2α-/- ECs migration seems to be independent of hypoxia. Moreover, apoptosis assay showed that ecHIF2a -/- ECs increased cell early apoptotic stage compared to WT in hypoxic conditions, but not in normoxia indicating the critical role of HIF2α in ECs survival during cardiac ischemia. Finally, several increased markers of inflammation, such as ICAM-1 and VCAM-1, are associated with HIF2a deletion. Conclusion: These data revealed an essential role of HIF2α in protecting cardiac remodeling in response to MI, which might through promoting endothelial cell migration, barrier function, as well as vascularization. Thus, HIF2α is a potential therapeutic target in the treatment of ischemic heart disease.