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BackgroundInvestigation of lymph node micrometastasis (mN) of gastric cancer has been focused on either T1 disease or T1-4N0 disease. Yet, it is unclear whether standard management algorithm toward poorly differentiated gastric cancer (PDGC) is more vulnerable to existence of mN, given its inherently biological aggressiveness, as compared with other histological types.Patients and methodsA surgical series (n = 3456) of gastric cancer categorized by histological differentiation was enrolled to analyze survival stratification. Of them, a cohort of T1-T4 N0 PDGC (n = 100) were subjected to cytokeratin immunohistochemistry, a surrogate of mN.ResultsCancer-specific survival by AJCC8 staging system could be nicely differentiated in both well-/moderately differentiated and signet ring cell types, while those between stage IA versus IB (p = 0.105), and stage IB versus IIA (p = 0.141) in PDGC could not. Thirteen (13%) out of 100 node-negative PDGC cases exhibited mN, with 5, 2, 5 and 1 cases occurring in T1, T2, T3, and T4 stage, respectively, without identifiable contributing factors. Prognostic performance of AJCC8 working upon PDGC became more discriminative by incorporating mN, as hazard ratio of stage IIIC referenced to stage IA increased from 43 to 78.ConclusionDefective discriminative survival of PDGC by standard staging algorithm prompted us to survey mN occurring in T1-T4N0 PDGC. The prognostic performance of AJCC8 working upon PDGC was enhanced by incorporating mN. As so, we recommend documentation of mN exclusively on node-negative PDGC that helps unveil stage migration phenomenon and switch to appropriate adjuvant therapy in need.  相似文献   
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《Cirugía espa?ola》2023,101(5):325-332
IntroductionIn our institution, the study of selective sentinel node biopsy (SLNB) is performed intraoperatively. The main objective of our study is to know the proportion of patients who benefits from the waiting of the results of SLNB.MethodsA retrospective analysis of patients operated on our center between January 1 st, 2018 and June 30, 2019 was carried out. We included women diagnosed with T1–T2 tumors, treated by lumpectomy and SLNB studied using OSNA method.ResultsOur study included 149 women. There were not statistically significant differences in terms of demographic data between the group treated with axillary lymph node dissection (ALND) and exclusively SLNB group. After analysis of SLN intraoperatively, there were performed 18 axillary lymphadenectomies. Only in six of these 18 cases, three or more sentinel nodes were founded. The location of the tumor, the presence of lymphovascular permeation and the total tumor load (TTL) showed statistically significant differences between groups. Only the TTL was established as the independent factor of the need for ALND.ConclusionsObtaining a deferred result of the SLNB allowed reducing the time of anesthesia and occupation of the operating room, since in a high percentage of cases an additional procedure is not performed.  相似文献   
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IntroductionLateral pelvic lymph node dissection (LPLND) is a technically challenging procedure and its learning curve has not been analysed against an oncologically relevant outcome. The purpose of the study was to determine the learning curve for LPLND in rectal cancers using nodal retrieval as performance measure.MethodsConsecutive LPLND for rectal adenocarcinomas from a single institution were retrospectively analysed. Cumulative sum (CUSUM) control charts were used to detect difference in performance with respect to lymph node yield. Negative binomial regression was used to determine factors influencing nodal harvest using Incidence Risk Ratios (IRR). Separate CUSUM curves were generated for open and minimally invasive surgeries (MIS).ResultsOne-hundred and twenty patients were included and all received preoperative radiation. MIS was used in 53.3%. Median lymph node yield was 6 with 20% nodal positivity. Increasing experience (IRR – 1.196) and MIS (IRR – 1.586) were the only factors that influenced nodal harvest. CUSUM charts revealed that learning curve was achieved after the 83rd case overall and after the 19 operations in MIS. There was a 20% increase in nodal yield after every 30 MIS LPLND performed.ConclusionsLearning curve for LPLND is relatively long and only increasing experience and minimally invasive operations increased nodal yield.  相似文献   
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IntroductionIn the recent edition of TNM staging system, pN3b gastric cancer were separated into the staging system for better prognosis accuracy. The definition of pN3b contains a large range of metastasis lymph nodes (mLNs). However, few studies have evaluated the prognosis of pN3b patients and it remains unknown whether these patients were reasonably assigned into the same substage.Materials and methodsA total of 642 pN3b patients from a multi-institutional cohort in China were included. Disease-specific survival (DSS) was estimated using the Kaplan-Meier method and the Cox proportional hazards regression analysis was used to identify the independent prognostic factors. Restricted cubic spine model was used to specify the association between the continuous variables and the logarithm Hazard ratios (HRs). The optimal cut-off value of mLNs for DSS was identified using the X-tile software.ResultsThe 5-year DSS rate of total pN3b cohort was 15.4%. The smooth curves showed a non-linear association between the mLNs and the logarithm HRs. All pN3b gastric cancer patients were divided into two subclassifications (pN3b1: 16-24 mLNs, pN3b2: ≥25 mLNs). Significant survival difference was observed between two subclassifications (P = 0.048). Additionally, more LNs examined could decrease the death risk of pN3b patients and bring survival benefit only in pN3b1 patients, but not in pN3b2 patients.ConclusionsWe proposed a novel subclassification of pN3b patients, which assigned patients into two subclassifications with significant survival difference. Future study should explore the prognosis value based on this novel subclassification in TNM staging system.  相似文献   
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IntroductionThe lymph node ratio (LNR), which represents the proportion of metastatic lymph nodes resected, has been found to be a prognostic variable in several cancers, but data for Medullary thyroid carcinoma (MTC) are sparse. The aim of this study was to determine the value of the LNR in predicting outcome in patients with MTC.Materials and methodsA retrospective multicenter study design of 107 patients with MTC who underwent total thyroidectomy with neck dissection between 1984 and 2016. The association of LNR with patient and tumor characteristics and prognostic factors was evaluated.ResultsStudy population consisted of 53.3% female, mean age at diagnosis was 50.3 ± 18.4 years; 16.8% had inherited MTC. LNR was positively correlated with tumor size (p = 0.018) and inversely correlated with age at diagnosis (p = 0.024). A higher LNR was associated with extrathyroidal extension (p < 0.001), multifocality (p = 0.001), bilateral tumor (p = 0.002), distant metastases (p < 0.001), and tumor recurrence (OR = 14.7, p < 0.001). LNR was also correlated to postoperative calcitonin levels (p < 0.001) and carcinoembryonic antigen (p = 0.011). LNR >0.1 was associated with shorter disease-specific survival in patients at risk: tumor larger than 20 mm at diagnosis (p = 0.013), sporadic MTC (p = 0.01), and age above 40 years at diagnosis (p = 0.004). Cox multivariate survival analysis revealed LNR as the only significant independent factor for disease free survival (p = 0.005).ConclusionsThis study showed that LNR correlates well with patient and tumor characteristics and prognostic variables. We suggest that LNR should be considered an important parameter for predicting outcome in MTC.  相似文献   
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BackgroundLymph node recurrences (LNR) from colorectal cancer (CRC) still represent a therapeutic challenge, as standardized recommendations have yet to be established. The aim of this study was to analyze short- and long-term oncological outcomes following resection of LNR from CRC.MethodsAll patients with previously resected CRC who underwent histopathologically confirmed LNR resection in 3 tertiary referral centers between 2010 and 2017 were reviewed. Short- and long-term outcomes were analyzed, mainly recurrence-free and overall survival. Further recurrences following LNR resection were also analyzed.ResultsOverall, 18 patients were included. Primary CRC was left-sided in 16 (89%) patients, staged T3-4 in 15 (83%), N+ in 14 (78%) and presented with synchronous metastases in 8 (43%). Median time interval between primary CRC and LNR resections was 31 months. Performed lymphadenectomies were aortocaval (n = 10), pelvic (n = 7), in hepatic pedicle (n = 3) and mesenteric (n = 1). Four patients had associated liver metastases resection. Three (17%) presented with postoperative complications, of which one Clavien-Dindo 3. Fourteen (78%) patients presented with further recurrences after a mean delay of 9 months, with 36% of patients presenting with early (<6 months) recurrence. Five (36%) patients could undergo secondary recurrence resection and 3 (21%) patients radiotherapy. Median overall survival following LNR resection reached 44 months.ConclusionsCurrent results suggest that LNR resection is feasible and associated with improved survival, in selected patients. Longer time interval between primary CRC resection and LNR occurrence appeared to be a favorable prognostic factor whereas multisite recurrence appeared to be associated with impaired long-term survival.  相似文献   
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BackgroundThis study aimed to investigate the incidence and distribution of regional lymph node metastasis according to tumor location, and to clarify whether tumor location could determine the extent of regional lymphadenectomy in patients with pathological T2 (pT2) gallbladder carcinoma.MethodsIn total, 81 patients with pT2 gallbladder carcinoma (25 with pT2a tumors and 56 with pT2b tumors) who underwent radical resection were enrolled. Tumor location was determined histologically in each gallbladder specimen.ResultsSurvival after resection was significantly worse in patients with pT2b tumors than those with pT2a tumors (5-year survival, 72% vs. 96%; p = 0.027). Tumor location was an independent prognostic factor on multivariate analysis (hazard ratio, 14.162; p = 0.018). The incidence of regional lymph node metastasis was significantly higher in patients with pT2b tumors than in those with pT2a tumors (46% vs. 20%; p = 0.028). However, the number of positive nodes was similar between the two groups (median, 2 vs. 2; p = 0.910). For node-positive patients with pT2b tumors, metastasis was found in every regional node group (12%–63%), whereas even for node-positive patients with pT2a tumors, metastasis was observed in regional node groups outside the hepatoduodenal ligament.ConclusionsTumor location in patients with pT2 gallbladder carcinoma can predict the presence or absence of regional lymph node metastasis but not the number and anatomical distribution of positive regional lymph nodes. The extent of regional lymphadenectomy should not be changed even in patients with pT2a tumors, provided that they are fit enough for surgery.  相似文献   
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IntroductionLymph node yield (LNY) in neck dissection has been identified as a prognostic factor in oral cavity cancer. The purpose of this study was to investigate the impact of additional use of optical imaging on LNY in therapeutic ND in oral cancer.MethodsConsecutive patients with oral squamous cell carcinoma with clinical neck metastasis planned for primary tumor resection were randomized to conventional neck dissection or near-infrared fluorescence (NIRF)-guided neck dissection, respectively. In the intervention group, patients were injected with ICG-Nanocoll prior to surgery. Intraoperatively, an optical hand-held camera system was used for lymph node identification. Also, NIRF imaging of the neck specimen was performed, and optical signals were pinned with needle markings to guide the pathological examination. The endpoint of the study was LNY per neck side in levels Ib-III.Results31 patients were included with 18 neck sides in the control group and 18 neck sides in the intervention group for evaluation. During NIRF-guided ND, individual lymph nodes could be identified by a bright fluorescent signal and individual tumor-related drainage patterns could be observed in the neck. The LNY in the intervention group was significantly higher compared to the control group (p = 0.032) with a mean of 24 LN (range: 12–33 LN in levels Ib-III compared to 18 LN (range: 10–36 LN) in the control group, respectively.ConclusionsNIRF-guided ND significantly improved the nodal yield compared to the control group. Intraoperative real-time optical imaging enabled direct visualization of tumor-related drainage patterns within the neck lymphatics.  相似文献   
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