Metastatic lymph nodes and prognosis assessed by the number of retrieved lymph nodes in gastric cancer

BACKGROUND The prognostic value of quantitative assessments of the number of retrieved lymph nodes(RLNs)in gastric cancer(GC)patients needs further study.AIM To discuss how to obtain a more accurate count of metastatic lymph nodes(MLNs)based on RLNs in different pT stages and then to evaluate patient prognosis.METHODS This study retrospectively analyzed patients who underwent GC radical surgery and D2/D2+LN dissection at the Cancer Hospital of Harbin Medical University from January 2011 to May 2017.Locally weighted smoothing was used to analyze the relationship between RLNs and the number of MLNs.Restricted cubic splines were used to analyze the relationship between RLNs and hazard ratios(HRs),and X-tile was used to determine the optimal cutoff value for RLNs.Patient survival was analyzed with the Kaplan-Meier method and log-rank test.Finally,HRs and 95%confidence intervals were calculated using Cox proportional hazards models to analyze independent risk factors associated with patient outcomes.RESULTS A total of 4968 patients were included in the training cohort,and 11154 patients were included in the validation cohort.The smooth curve showed that the number of MLNs increased with an increasing number of RLNs,and a nonlinear relationship between RLNs and HRs was observed.X-tile analysis showed that the optimal number of RLNs for pT1-pT4 stage GC patients was 26,31,39,and 45,respectively.A greater number of RLNs can reduce the risk of death in patients with pT1,pT2,and pT4 stage cancers but may not reduce the risk of death in patients with pT3 stage cancer.Multivariate analysis showed that RLNs were an independent risk factor associated with the prognosis of patients with pT1-pT4 stage cancer(P=0.044,P=0.037,P=0.003,P<0.001).CONCLUSION A greater number of RLNs may not benefit the survival of patients with pT3 stage disease but can benefit the survival of patients with pT1,pT2,and pT4 stage disease.For the pT1,pT2,and pT4 stages,it is recommended to retrieve 26,31 and 45 LNs,respectively.

Targeted delivery of docetaxel to the metastatic lymph nodes:A comparison study between nanoliposomes and activated carbon nanoparticles

The objective of this study is to compare the targeting ability of activated carbon nanoparticles and nanoliposomes,which are used as carriers for delivering docetaxel(DTX)to the metastatic lymph nodes.In this study,we first prepared the DTX-loaded activated carbon nanoparticles(DTX-AC-NPs)by modifying the activated carbon with nitric acid oxidation and absorbing DTX in the concentrated nitro-oxide nanocarbon.We then prepared DTX-loaded nanoliposomes(DTX-LPs)by the proliposome method.The physiochemical properties of DTX-AC-NPs and DTX-LPs were carefully evaluated in vitro.The metastatic lymph node uptake and the injection site retention were investigated by analyzing the DTX concentration in metastatic lymph nodes and injection sites.The result showed that DTX-AC-NPs and DTX-LPs with suitable and stable physicochemical properties could be used for in vivo lymph node targeting studies.DTX-AC-NPs significantly increased DTX-AUC_((0-24)) and prolonged DTX-retention in metastatic lymph nodes compared to DTX-LPs and non-modified activate carbon in vivo.This study demonstrated activated carbon nanoparticles may be potential intralymphatic drug delivery system to preferentially target regional metastatic lymph nodes.

Deep neural network-assisted computed tomography diagnosis of metastatic lymph nodes from gastric cancer

Background:Artificial intelligence-assisted image recognition technology is currently able to detect the target area of an image and fetch information to make classifications according to target features.This study aimed to use deep neural netAVorks for computed tomography(CT)diagnosis of perigastric metastatic lymph nodes(PGMLNs)to simulate the recognition of lymph nodes by radiologists,and to acquire more accurate identification results.Methods:A total of 1371 images of suspected lymph node metastasis from enhanced abdominal CT scans were identified and labeled by radiologists and were used with 18,780 original images for faster region-based convolutional neural networks(FR-CNN)deep learning.The identification results of 6000 random CT images from 100 gastric cancer patients by the FR-CNN were compared with results obtained from radiologists in terms of their identification accuracy.Similarly,1004 CT images with metastatic lymph nodes that had been post-operatively confirmed by pathological examination and 11,340 original images were used in the identification and learning processes described above.The same 6000 gastric cancer CT images were used for the verification,according to which the diagnosis results were analyzed.Results:In the initial group,precision-recall curves were generated based on the precision rates,the recall rates of nodule classes of the training set and the validation set;the mean average precision(mAP)value was 0.5019.To verify the results of the initial learning group,the receiver operating characteristic curves was generated,and the corresponding area under the curve(AUC)value was calculated as 0.8995.After the second phase of precise learning,all the indicators were improved,and the mAP and AUC values were 0.7801 and 0.9541,respectively.Conclusion:Through deep learning,FR-CNN achieved high judgment effectiveness and recognition accuracy for CT diagnosis of PGMLNs.

Differential diagnosis of metastasis from non-metastatic lymph nodes in cervical cancers： pilot study of diffusion weighted imaging with background suppression at 3T magnetic resonance

Background Diffusion weighted imaging with background suppression （DWIBS） is potentially useful in detecting metastatic lymph nodes. This study aimed to evaluate the efficacy of DWIBS at 3T magnetic resonance （MR） for diagnosing metastatic lymph nodes in cervical cancer.Methods This retrospective study included 25 patients with cervical cancer who underwent MR examination and were treated by hysterectomy and lymphadenectomy. The metastatic and non-metastatic lymph nodes were histologically proven by operation. Apparent diffusion coefficient （ADC） values, long-axis diameters, short-axis diameters, ratio of short- to long-axis diameters of all the identifiable lymph nodes were measured and compared.Results Twenty-five primary tumor lesions, 17 metastatic lymph nodes and 140 non-metastatic lymph nodes were pathologically confirmed in 25 cases with cervical cancer. The difference of ADC values between primary tumor lesions,metastatic and non-metastatic lymph nodes were statistically significant （F=7.93, P=0.001）. There was no statistically significant difference between primary tumor lesions of cervical cancer and metastatic lymph nodes （t=-0.75, P=-0.456）,and the difference between primary tumor lesions and non-metastatic lymph nodes was statistically significant （t =4.68, P〈0.001）. The ADC values, long-axis diameters, short-axis diameters, ratio of short- to long-axis diameters of metastatic and non-metastatic lymph nodes were （0.86±0.36）×10-3 mm2/s vs. （1.12±0.34）×10-3 mm2/s, （1.51±0.41） cm vs.（1.19±0.36） cm, （1.16±0.35） cm vs. （0.77±0.22） cm, 0.78±0.17 vs. 0.68±0.19 respectively, and statistically significant difference existed between two groups.Conclusions DWIBS at 3T MR has the distinct advantages in detecting pelvic lymph nodes of cervical cancer.Quantitative measurement of ADC values could reflect the degree of restriction of diffusion of metastatic and non-metastatic lymph nodes. The combination of size and ADC value would be useful in the accurate diagnosis of metastatic lymph nodes.

Prognostic impact of metastatic lymph node ratio on gastric cancer after curative distal gastrectomy

AIM:To investigate the prognostic impact of metastatic lymph node ratio(rN) on gastric cancer after curative distal gastrectomy.METHODS:A total of 634 gastric cancer patients who underwent curative resection(R0) of lymph nodes at distal gastrectomy in 1995-2004.Correlations between positive nodes and retrieved nodes,between rN and retrieved nodes,and between rN and negative lymph node(LN) count were analyzed respectively.Prognostic factors were identif ied by univariate and multivariate analyses.Staging accuracy of the pN category(5th UICC/TNM system) and the rN category was compared according to the survival rates of patients.A linear regression model was used to identify the relation between rN and 5-year survival rate of the patients.RESULTS:The number of dissected LNs was related with metastatic LNs but not related with rN.Cox regression analysis showed that depth of invasion,pN and rN category were the independent predictors of survival(P < 0.05).There was a signif icant difference in survival between LN stages classif ied by the rN category or by the pN category(P < 0.05).However,no signif icant difference was found in survival rate between LN stages classif ied by the pN category or by the rN category(P > 0.05).Linear regression model showed a signif icant linear correlation between rN and the 5-year survival rate of gastric cancer patients(β = 0.862,P < 0.001).Pearson's correlation test revealed that negative LN count was negatively correlated with rN(P < 0.001).CONCLUSION:rN category is a better prognostic tool than the 5th UICC pN category for gastric cancer patients after curative distal gastrectomy.Increased negative LN count can reduce rN and improve the survival rate of gastric cancer patients.

A clinical analysis of risk factor with lymph node metastatic recurrence in patients with N0 esophageal cancer after Ivor-Lewis Esophagectomy

Objective To investigate the risk factors with lymph node metastatic recurrence in patients with N0 esophageal cancer after Ivor-Lewis Esophagectomy. Methods The subjects were 82 patients with pN0 esophagea cancer who underwent Ivor-Lewis esophagectomy from January 2001 to January 2005. By using RT-PCR,VEGF C mRNA was detected in tumor issues,and Mucin (MUC1) mRNA was detected in lymph nodes. The Kaplan-Meier method was used to calculate the survival

Retrieved lymph nodes from different anatomic groups in gastric cancer:a proposed optimal number,comparison with other nodal classification strategies and its impact on prognosis

Background:The optimal number of retrieved lymph nodes(LNs)in gastric cancer(GC)is still debatable and previ-ous studies proposing new classification alternatives mostly focused on the number of retrieved LNs without proper consideration on the anatomic nodal groups’location.Here,we assessed the impact of retrieved LNs from different nodal location groups on the survival of GC patients.Methods:Stage I-III gastric cancer patients who had radical gastrectomy were investigated.LN grouping was deter-mined according to the 13th edition of the JCGC.The optimal cut-off values of retrieved LNs in different LN groups(Group 1 and 2)were calculated,based on which a proposed nodal classification(rN)simultaneously accounting the optimal number and location of retrieved LNs was proposed.The performance of rN was then compared to that of LN ratio,log-odds of metastatic LNs(LODDs)and the 8th edition of the Union for International Cancer Control/American Joint Committee on Cancer(UICC/AJCC)N classification.Results:The optimal cut-off values for Group 1 and 2 were 13 and 9,respectively.The 5-year overall survival(OS)was higher for patients in retrieved Group 1 LNs>13(vs.Group 1 LNs≤13,63.2%vs.57.9%,P=0.005)and retrieved Group 2 LNs>9(vs.Group 2 LNs≤9,72.5%vs.60.7%,P=0.009).Patients staged as pN0-3b were sub classified using this Group 1 and 2 nodal analogy.The OS of pN0-N2 patients in retrieved Group 1 LNs>13 or Group 2 LNs>9 were superior to those in retrieved Group 1 LNs≤13 and Group 2 LNs≤9(All P<0.05);except for pN3 patients.The rN clas-sification was formulated and demonstrated better 5-year OS prognostication performance as compared to the LNR,LODDs,and the 8th UICC/AJCC N staging system.Conclusions:The retrieval of>13 and>9 LNs for Group 1 and Group 2,respectively,could represent an alternative lymph node retrieval approach in radical gastrectomy for more precise survival prognostication and minimizing staging migration,especially if>16 LNs is found to be difficult.