Influence of donor age on liver transplantation outcomes: A multivariate analysis and comparative study

BACKGROUND The growing disparity between the rising demand for liver transplantation(LT)and the limited availability of donor organs has prompted a greater reliance on older liver grafts.Traditionally,utilizing livers from elderly donors has been associated with outcomes inferior to those achieved with grafts from younger donors.By accounting for additional risk factors,we hypothesize that the utili-zation of older liver grafts has a relatively minor impact on both patient survival and graft viability.AIM To evaluate the impact of donor age on LT outcomes using multivariate analysis and comparing young and elderly donor groups.METHODS In the period from April 2013 to December 2018,656 adult liver transplants were performed at the University Hospital Merkur.Several multivariate Cox propor-tional hazards models were developed to independently assess the significance of donor age.Donor age was treated as a continuous variable.The approach involved univariate and multivariate analysis,including variable selection and assessment of interactions and transformations.Additionally,to exemplify the similarity of using young and old donor liver grafts,the group of 87 recipients of elderly donor liver grafts(≥75 years)was compared to a group of 124 recipients of young liver grafts(≤45 years)from the dataset.Survival rates of the two groups were estimated using the Kaplan-Meier method and the log-rank test was used to test the differences between groups.RESULTS Using multivariate Cox analysis,we found no statistical significance in the role of donor age within the constructed models.Even when retained during the entire model development,the donor age's impact on survival remained insignificant and transformations and interactions yielded no substantial effects on survival.Consistent insigni-ficance and low coefficient values suggest that donor age does not impact patient survival in our dataset.Notably,there was no statistical evidence that the five developed models did not adhere to the proportional hazards assumption.When comparing donor age groups,transplantation using elderly grafts showed similar early graft function,similar graft(P=0.92),and patient survival rates(P=0.86),and no significant difference in the incidence of postoperative complications.CONCLUSION Our center's experience indicates that donor age does not play a significant role in patient survival,with elderly livers performing comparably to younger grafts when accounting for other risk factors.

Efficacy evaluation and survival analysis of the combination of oxaliplatin plus Teysuno (SOX) with immune checkpoint inhibitors in the conversion therapy of locally advanced gastric cancer

Background:The efficacy of combining immune checkpoint inhibitors(ICIs)with chemotherapy in neoadjuvant therapy for locally advanced gastric cancer has been explored.However,limited research exists on its effectiveness in conversion therapy,and its superiority over standalone chemotherapy remains to be elucidated.This study aims to investigate the efficacy and survival outcomes of patients treated with ICIs in combination with conversion therapy for locally advanced gastric cancer.Methods:Retrospective data from patients with locally advanced gastric cancer treated with either oxaliplatin+S-1(SOX)alone or in combination with ICIs in conversion therapywere collected.Clinical andpathological characteristics,disease-free survival,andefficacy assessments in nonoperable patients were compared between the 2 treatment groups.Efficacy was further evaluated through dynamic changes in serum markers,and patients’quality of life was assessed using the QLQ-STO22(Gastric Cancer–Specific Quality of Life Questionnaire)quality-of-life measurement scale.Results:A total of 140 patients underwent conversion therapy:80 in the SOX alone group and 60 in the SOX combined with the ICIs group.There were no significant differences in baseline characteristics between the 2 groups.Compared with the SOX alone group,the SOX combined with ICIs group exhibited a higher conversion rate(83.3%vs 75%,P=0.23),R0 resection rate(90.0%vs 83.3%,P=0.31),pathological complete response(pCR)rate(18%vs 5%,P=0.02),median disease-free survival(21.4 vs 16.9 months,P=0.007),the objective response rate in nonoperable patients(60%vs 40%,P=0.301),and median progression-free survival time(7.9 vs 5.7 months,P=0.009).The QLQ-STO22 quality-of-life assessment revealed statistically significant improvements in pain,swallowing difficulties,and dietary restrictions in the combination therapy group compared with those in the monotherapy group.The enhanced efficacy of immune combination with SOX is evident,as demonstrated by the significantly prolonged surgical duration in operated patients(206.6±26.6 min vs 197.8±19.8 min,P=0.35)and intraoperative blood loss(158.9±21.2 mL vs 148.9±25.1 mL,P=0.59).No significant differences were observed in postoperative complications.Conclusions:Compared with the SOX conversion therapy regimen,SOX combined with ICIs demonstrated higher conversion rates,R0 resection rates,pathological response rates,and disease-free survival without increasing surgical difficulty or complications.Nonoperable patients also experienced longer progression-free survival and objective response rates.

Clinical features and prognostic factors in 49 patients with follicular lymphoma at a single center:A retrospective analysis

BACKGROUND Follicular lymphoma(FL)is a type of B-cell lymphoma that originates at the germinal center and has a low malignancy rate.FL has become the most common inert lymphoma in Europe and America but has a relatively low incidence in Asia.AIM To explore the clinical features,curative effects,and prognostic factors of FL.METHODS Completed medical records of 49 patients with FL who were admitted to the Ningbo First Hospital from June 2010 to June 2021 were examined.These patients were definitively diagnosed by pathological biopsy or immunohistochemical staining.The diagnostic criteria were based on the 2008 World Health Organization classification of lymphomas.Ann Arbor staging was performed according to the imaging and bone marrow examination results.Risk stratification of all patients was performed based on the International Prognostic Index(IPI),age-adjusted IPI,Follicular Lymphoma International Prognosis Index(FLIPI),and FLIPI2 to compare the efficacy of different treatment regimens and analyze the related prognostic factors.RESULTS The age of onset in patients ranged from 24 to 76 years,with a median age of 51 years.Most patients developed the disease at 40–59 years of age,and the male:female ratio was 1.6:1.No significant difference was noted in the curative effect between the non-chemotherapy,combined chemotherapy,and other chemotherapy regimens(P>0.05).Hemoglobin(Hb)level<120 g/L,Ki-67 value>50%,bone marrow involvement,and clinical stagesⅢ–IV were associated with a poor prognosis of FL(P<0.05).However,the influence of other indicators was not statistically significant.Risk grouping was performed using the FLIPI,and the results showed that 24.5%,40.8%,and 34.7%of patients were in the low-,moderate-,and high-risk groups,respectively.According to the survival analysis results,the survival rate of patients was lower in the high-risk group than in the other low-risk and moderate-risk groups(P<0.05).CONCLUSION FL mainly occurs in middle-aged and elderly men,primarily affecting lymph nodes and bone marrow.Hb level,Ki-67 value,bone marrow involvement,and clinical staging were used to evaluate prognosis.

Correction:Propensity-matched analysis of patients with intrahepatic cholangiocarcinoma or mixed hepatocellularcholangiocarcinoma and hepatocellular carcinoma undergoing a liver transplant

Rereading the article“Propensity-matched analysis of patients with intrahepatic cholangiocarcinoma or mixed hepatocellular-cholangiocarcinoma and hepatocellular carcinoma undergoing a liver transplant”(DOI:10.5306/wjco.v13.i8.688),published on August 24,we observe,with concern,that figures 3 and 4 are wrong.The authors have attached the correct figures for correction.

Bioinformatics analysis of key genes associated with the prognosis of breast cancer

Objective:We sought to identify potential therapeutic targets for breast cancer patients by employing a bioinformatics analysis to screen for genes linked with an unfavorable prognosis.Methods:The Gene Expression Omnibus(GEO)database was utilized to obtain three gene expression profile datasets,namely GSE42568,GSE86374,and GSE71053.To identify differentially expressed genes(DEGs),the GEO2R online tool was employed.Subsequently,a func-tional enrichment analysis was conducted.Moreover,a protein-protein interaction network was established using STRING,and DEGs were subjected to module analysis via Cytoscape software to identify pivotal genes.Additionally,the selected pivotal genes underwent further ex-amination and validation utilizing three databases:GEPIA,UALCAN,and Kaplan-Meier Plotter.Results:A total of 121 DEGs were detected,comprising 74 genes with increased expression and 47 genes with decreased expression.Ten key genes were identified:HMMR,RRM2,CDK1,TOP2A,AURKA,CCNB1,MAD2L1,KIF2C,BUB1B,UBE2C.Validation in the GEPIA database revealed high expression levels for all key genes except CDK1.A survival analysis conducted using the Kaplan-Meier Plotter database revealed noteworthy associations between nine crucial genes and the overall survival(OS)of individuals diagnosed with breast cancer.Moreover,these nine key genes exhibited significantly increased expression across different molecular subtypes of breast cancer according to the UALCAN data platform.Conclusions:We identified nine crucial genes significantly linked to the onset,progression,and unfavorable prognosis of breast cancer,providing potential targets for novel treatment options and biomarkers to predict patient outcomes.

Survival Analysis Using Cox Proportional Hazards Regression for Pile Bridge Piles Under Wet Service Conditions

This paper studies the deterioration of bridge substructures utilizing the Long-Term Bridge Performance(LTBP)Program InfoBridge^(TM)and develops a survival model using Cox proportional hazards regression.The survival anal­ysis is based on the National Bridge Inventory(NBI)dataset.The study calculates the survival rate of reinforced and prestressed concrete piles on bridges under marine conditions over a 29-year span(from 1992 to 2020).The state of Maryland is the primary focus of this study,with data from three neighboring regions,the District of Columbia,Vir­ginia,and Delaware to expand the sample size.The data obtained from the National Bridge Inventory are condensed and filtered to acquire the most relevant information for model development.The Cox proportional hazards regres­sion is applied to the condensed NBI data with six parameters:Age,ADT,ADTT,number of spans,span length,and structural length.Two survival models are generated for the bridge substructures:Reinforced and prestressed concrete piles in Maryland and reinforced and prestressed concrete piles in wet service conditions in the District of Columbia,Maryland,Delaware,and Virginia.Results from the Cox proportional hazards regression are used to construct Markov chains to demonstrate the sequence of the deterioration of bridge substructures.The Markov chains can be used as a tool to assist in the prediction and decision-making for repair,rehabilitation,and replacement of bridge piles.Based on the numerical model,the Pile Assessment Matrix Program(PAM)is developed to facilitate the assessment and main­tenance of current bridge structures.The program integrates the NBI database with the inspection and research reports from various states’department of transportation,to serve as a tool for condition state simulation based on mainte­nance or rehabilitation strategies.

Association of tumor budding with clinicopathological features and prognostic value in stage III-IV colorectal cancer

BACKGROUND Tumor budding(TB)has emerged as a promising independent prognostic biomarker in colorectal cancer(CRC).The prognostic role of TB has been extensively studied and currently affects clinical decision making in patients with stage I and II CRC.However,existing prognostic studies on TB in stage III CRC have been confined to small retrospective cohort studies.Consequently,this study investigated the correlation among TB categories,clinicopathological features,and prognosis in stage III-IV CRC to further enhance the precision and individualization of treatment through refined prognostic risk stratification.AIM To analyze the relationship between TB categories and clinicopathological characteristics and assess their prognostic value in stage III-IV CRC to further refine the prognostic risk stratification of stage III-IV CRC.METHODS The clinical data of 547 CRC patients were collected for this retrospective study.Infiltration at the front edge of the tumor buds was counted according to the 2016 International Tumor Budding Consensus Conference guidelines.RESULTS Multivariate Cox proportional hazards regression analysis demonstrated that chemotherapy(P=0.004),clinical stage IV(P<0.001),≥4 regional lymph node metastases(P=0.004),left-sided colonic cancer(P=0.040),and Bd 2-3(P=0.002)were independent prognostic factors in patients with stage III-IV CRC.Moreover,the density of tumor infiltrating lymphocytes was higher in Bd 1 than in Bd 2-3,both in the tumor stroma and its invasive margin.CONCLUSION TB has an independent predictive prognostic value in patients with stage III-IV CRC.It is recommended to complete the TB report of stage III-IV CRC cases in the standardized pathological report to further refine risk stratification.

Establishment and evaluation of a prognostic model for patients with unresectable gastric cancer liver metastases

BACKGROUND Liver metastases(LM)is the primary factor contributing to unfavorable outcomes in patients diagnosed with gastric cancer(GC).The objective of this study is to analyze significant prognostic risk factors for patients with GCLM and develop a reliable nomogram model that can accurately predict individualized prognosis,thereby enhancing the ability to evaluate patient outcomes.AIM To analyze prognostic risk factors for GCLM and develop a reliable nomogram model to accurately predict individualized prognosis,thereby enhancing patient outcome assessment.METHODS Retrospective analysis was conducted on clinical data pertaining to GCLM(type III),admitted to the Department of General Surgery across multiple centers of the Chinese PLA General Hospital from January 2010 to January 2018.The dataset was divided into a development cohort and validation cohort in a ratio of 2:1.In the development cohort,we utilized univariate and multivariate Cox regression analyses to identify independent risk factors associated with overall survival in GCLM patients.Subsequently,we established a prediction model based on these findings and evaluated its performance using receiver operator characteristic curve analysis,calibration curves,and clinical decision curves.A nomogram was created to visually represent the prediction model,which was then externally validated using the validation cohort.RESULTS A total of 372 patients were included in this study,comprising 248 individuals in the development cohort and 124 individuals in the validation cohort.Based on Cox analysis results,our final prediction model incorporated five independent risk factors including albumin levels,primary tumor size,presence of extrahepatic metastases,surgical treatment status,and chemotherapy administration.The 1-,3-,and 5-years Area Under the Curve values in the development cohort are 0.753,0.859,and 0.909,respectively;whereas in the validation cohort,they are observed to be 0.772,0.848,and 0.923.Furthermore,the calibration curves demonstrated excellent consistency between observed values and actual values.Finally,the decision curve analysis curve indicated substantial net clinical benefit.CONCLUSION Our study identified significant prognostic risk factors for GCLM and developed a reliable nomogram model,demonstrating promising predictive accuracy and potential clinical benefit in evaluating patient outcomes.

Multiple myeloma survival in New South Wales, Australia, by treatment era to 2020

Objective: Australia has relatively high multiple myeloma(MM) incidence and mortality rates. Advancements in MM treatment over recent decades have driven improvements in MM survival in high-income countries;however, reporting in Australia is limited. We investigated temporal trends in population-wide MM survival across 3 periods of treatment advancements in New South Wales(NSW), Australia.Methods: Individuals with an MM diagnosis in the NSW Cancer Registry between 1985 and 2015 with vital follow-up to 2020, were categorized into 3 previously defined treatment eras according to their diagnosis date(1985±1995, chemotherapy only;1996±2007, autologous stem cell transplantation;and 2008±2015, novel agents including proteasome inhibitors and immunomodulatory drugs). Both relative survival and cause-specific survival according to Fine and Gray's competing risks cumulative incidence function were calculated by treatment era and age at diagnosis.Results: Overall, 11,591 individuals were included in the study, with a median age of 70 years at diagnosis. Five-year relative survival improved over the 36-year(1985±2020) study period(31.0% in 1985±1995;41.9% in 1996±2007;and 56.1% in 2008±2015). For individuals diagnosed before 70 years of age, the 5-year relative survival nearly doubled, from 36.5% in 1985±1995 to 68.5% in 2008±2015. Improvements for those > 70 years of age were less pronounced between 1985±1995 and 1996±2007;however, significant improvements were observed for those diagnosed in 2008±2015. Similar overall and age-specific patterns were observed for causespecific survival. After adjustment for gender and age at diagnosis, treatment era was strongly associated with both relative and cause-specific survival(P < 0.0001).Conclusions: Survival of individuals with MM is improving in Australia with treatment advances. However, older age groups continue to experience poor survival outcomes with only modest improvements over time. Given the increasing prevalence of MM in Australia, the effects of MM treatment on quality of life, particularly in older age, warrant further attention.

Key Genes Involved in the Beneficial Mechanism of Hyperbaric Oxygen for Glioblastoma and Predictive Indicators of Hyperbaric Oxygen Prolonging Survival in Glioblastoma Patients

Objective The prognosis of glioblastoma is poor,and therapy-resistance is largely attributed to intratumor hypoxia.Hyperbaric oxygen(HBO)effectively alleviates hypoxia.However,the sole role of HBO in glioblastoma remains controversial.We previously reported that HBO can promote apoptosis,shorten protrusions,and delay growth of glioblastoma,but the molecular mechanism is unclear.We aimed to test candidate genes in HBO-exposed glioblastoma cells and to analyze their correlation with the survival of glioblastoma patients.Methods Glioblastoma cell lines exposed to repetitive HBO or normobaric air(NBA)were collected for RNA isolation and microarray data analysis.GO analysis,KEGG pathway analysis and survival analysis of the differentially expressed genes(DEGs)were performed.Results HBO not only inhibited hypoxia-inducing genes including CA9,FGF11,PPFIA4,TCAF2 and SLC2A12,but also regulated vascularization by downregulating the expression of COL1A1,COL8A1,COL12A1,RHOJ and FILIP1L,ultimately attenuated hypoxic microenvironment of glioblastoma.HBO attenuated inflammatory microenvironment by reducing the expression of NLRP2,CARD8,MYD88 and CD180.HBO prevented metastasis by downregulating the expression of NTM,CXCL12,CXCL13,CXCR4,CXCR5,CDC42,IGFBP3,IGFBP5,GPC6,MMP19,ADAMTS1,EFEMP1,PTBP3,NF1 and PDCD1.HBO upregulated the expression of BAK1,PPIF,DDIT3,TP53I11 and FAS,whereas downregulated the expression of MDM4 and SIVA1,thus promoting apoptosis.HBO upregulated the expression of CDC25A,MCM2,PCNA,RFC33,DSCC1 and CDC14A,whereas downregulated the expression of ASNS,CDK6,CDKN1B,PTBP3 and MAD2L1,thus inhibiting cell cycle progression.Among these DEGs,17 indicator-genes of HBO prolonging survival were detected.Conclusions HBO is beneficial for glioblastoma.Glioblastoma patients with these predictive indicators may prolong survival with HBO therapy.These potential therapeutic targets especially COL1A1,ADAMTS1 and PTBP3 deserve further validation.

Curcumin for gastric cancer:Mechanism prediction via network pharmacology,docking,and in vitro experiments

BACKGROUND Curcumin originates from the natural herb turmeric,and its antitumor effects have been known about for a long time.However,the mechanism by which curcumin affects gastric cancer(GC)has not been elucidated.AIM To elucidate the potential mechanisms of curcumin in the treatment of GC.METHODS Network pharmacological approaches were used to perform network analysis of Curcumin.We first analyzed Lipinski’s Rule of Five for the use of Curcumin.Curcumin latent targets were predicted using the PharmMapper,SwissTargetPrediction and DrugBank network databases.GC disease targets were mined through the GeneCard,OMIM,DrugBank and TTD network databases.Then,GO enrichment,KEGG enrichment,protein-protein interaction(PPI),and overall survival analyses were performed.The results were further verified through molecular docking,differential expression analysis and cell experiments.RESULTS We identified a total of 48 curcumin-related genes with 31 overlapping GC-related targets.The intersection targets between curcumin and GC have been enriched in 81 GO biological processes and 22 significant pathways.Following PPI analysis,6 hub targets were identified,namely,estrogen receptor 1(ESR1),epidermal growth factor receptor(EGFR),cytochrome P450 family 3 subfamily A member 4(CYP3A4),mitogen-activated protein kinase 14(MAPK-14),cytochrome P450 family 1 subfamily A member 2(CYP1A2),and cytochrome p450 family 2 subfamily B member 6(CYP2B6).These factors are correlated with decreased survival rates among patients diagnosed with GC.Molecular docking analysis further substantiated the strong binding interactions between Curcumin and the hub target genes.The experimental findings demonstrated that curcumin not only effectively inhibits the growth of BGC-823 cells but also suppresses their proliferation.mRNA levels of hub targets CYP3A4,MAPK14,CYP1A2,and CYP2B6 in BGC-823 cells were significantly increased in each dose group.CONCLUSION Curcumin can play an anti-GC role through a variety of targets,pathways and biological processes.

Nomogram model including LATS2 expression was constructed to predict the prognosis of advanced gastric cancer after surgery

BACKGROUND Gastric cancer is a leading cause of cancer-related deaths worldwide.Prognostic assessments are typically based on the tumor-node-metastasis(TNM)staging system,which does not account for the molecular heterogeneity of this disease.LATS2,a tumor suppressor gene involved in the Hippo signaling pathway,has been identified as a potential prognostic biomarker in gastric cancer.AIM To construct and validate a nomogram model that includes LATS2 expression to predict the survival prognosis of advanced gastric cancer patients following ra-dical surgery,and compare its predictive performance with traditional TNM staging.METHODS A retrospective analysis of 245 advanced gastric cancer patients from the Fourth Hospital of Hebei Medical University was conducted.The patients were divided into a training group(171 patients)and a validation group(74 patients)to deve-lop and test our prognostic model.The performance of the model was determined using C-indices,receiver operating characteristic curves,calibration plots,and decision curves.RESULTS The model demonstrated a high predictive accuracy with C-indices of 0.829 in the training set and 0.862 in the validation set.Area under the curve values for three-year and five-year survival prediction were significantly robust,suggesting an excellent discrimination ability.Calibration plots confirmed the high concordance between the predictions and actual survival outcomes.CONCLUSION We developed a nomogram model incorporating LATS2 expression,which significantly outperformed conven-tional TNM staging in predicting the prognosis of advanced gastric cancer patients postsurgery.This model may serve as a valuable tool for individualized patient management,allowing for more accurate stratification and im-proved clinical outcomes.Further validation in larger patient cohorts will be necessary to establish its generaliza-bility and clinical utility.

Clinical significance of peripheral blood immune cells in patients with gastric cancer after surgery

BACKGROUND Gastric cancer is one of the most common malignant tumors worldwide,and surgical resection is one of the main ways to treat gastric cancer.However,the immune status of postoperative patients is crucial for prognosis and survival,and immune cells play an important role in this process.Therefore,it is helpful to understand the immune status of postoperative patients by evaluating the levels of peripheral blood immune cells,especially total T cells(CD3+),helper T cells(CD3+CD4+),and suppressor T cells(CD3+CD8+),and its relationship to sur-vival.AIM To analyzed the immune cells in peripheral blood of patients with gastric cancer after surgery,detect the levels of total T cells,helper T cells and suppressor T cells.METHODS A total of 58 patients with gastric cancer who received surgical treatment were included in the retrospective study.Flow cytometry was used to detect the level of peripheral blood immune cells and analyze the correlation between total T cells,helper T cells and inhibitory T cells.To explore the relationship between these immune markers and patient survival.RESULTS The results showed that the levels of total T cells,helper T cells,and suppressor T cells changed in patients after gastric cancer surgery.There was a significant positive correlation between total T cells,helper T cells and suppressor T cells(r=0.35,P<0.01;r=0.56,P<0.01).However,there was a negative correlation between helper T cells and suppressor T cells(r=-0.63,P<0.01).Follow-up showed that the survival rate of patients in the high-level total T cell group was significantly higher than that in the low-level group(28.87±24.98 months vs 18.42±16.21 months).The survival curve shows that the curve of patients in the high-level group is shifted to the upper right,and that of the low-level group is shifted downward.There was no significant difference between the levels of helper T cells and suppressor T cells and patient survival time.CONCLUSION By detecting peripheral blood immune cells with flow cytometry,we can initially evaluate the immune status of patients after gastric cancer surgery and initially explore its relationship with patient survival.

Recipient functional status impacts on short and long-term intestinal transplant outcomes in United States adults

BACKGROUND Recipient functional status prior to transplantation has been found to impact post-transplant outcomes in heart,liver and kidney transplants.However,information on how functional status,before and after transplant impacts post-transplant survival outcomes is lacking.AIM To investigate the impact of recipient functional status on short and long term intestinal transplant outcomes in United States adults.METHODS We conducted a retrospective cohort study on 1254 adults who underwent first-time intestinal transplantation from 2005 to 2022.The primary outcome was mortality.Using the Karnofsky Performance Status,functional impairment was categorized as severe,moderate and normal.Analyses were conducted using Kaplan-Meier curves and multivariable Cox regression.RESULTS The median age was 41 years,majority(53.4%)were women.Severe impairment was present in 28.3%of recipients.The median survival time was 906.6 days.The median survival time was 1331 and 560 days for patients with normal and severe functional impairment respectively.Recipients with severe impairment had a 56%higher risk of mortality at one year[Hazard ratio(HR)=1.56;95%CI:1.23–1.98;P<0.001]and 58%at five years(HR=1.58;95%CI:1.24–2.00;P<0.001)compared to patients with no functional impairment.Recipients with worse functional status after transplant also had poor survival outcomes.CONCLUSION Pre-and post-transplant recipient functional status is an important prognostic indicator for short-and long-term intestinal transplant outcomes.

Comparison of Semi-Parametric Shared Frailty Models for Bees’Survival

Survival analysis is a fundamental tool in medical science for time-to-event data. However, its application to colony organisms like bees poses challenges due to their social nature. Traditional survival models may not accurately capture the interdependence among individuals within a colony. Frailty models, accounting for shared risks within groups, offer a promising alternative. This study evaluates the performance of semi-parametric shared frailty models (gamma, inverse normal, and positive stable-in comparison to the traditional Cox model using bees’ survival data). We examined the effect of misspecification of the frailty distribution on regression and heterogeneity parameters using simulation and concluded that the heterogeneity parameter was more sensitive to misspecification of the frailty distribution and choice of initial parameters (cluster size and true heterogeneity parameter) compared to the regression parameter. From the data, parameter estimates for covariates were close for the four models but slightly higher for the Cox model. The shared gamma frailty model provided a better fit to the data in comparison with the other models. Therefore, when focusing on regression parameters, the gamma frailty model is recommended. This research underscores the importance of tailored survival methodologies for accurately analyzing time-to-event data in social organisms.

Application of a 2 Parameter Weibull Distribution in Modeling of State Holding Time in HIV/AIDS Transition Dynamics

This study investigates the application of the two-parameter Weibull distribution in modeling state holding times within HIV/AIDS progression dynamics. By comparing the performance of the Weibull-based Accelerated Failure Time (AFT) model, Cox Proportional Hazards model, and Survival model, we assess the effectiveness of these models in capturing survival rates across varying gender, age groups, and treatment categories. Simulated data was used to fit the models, with model identification criteria (AIC, BIC, and R2) applied for evaluation. Results indicate that the AFT model is particularly sensitive to interaction terms, showing significant effects for older age groups (50 - 60 years) and treatment interaction, while the Cox model provides a more stable fit across all age groups. The Survival model displayed variability, with its performance diminishing when interaction terms were introduced, particularly in older age groups. Overall, while the AFT model captures the complexities of interactions in the data, the Cox model’s stability suggests it may be better suited for general analyses without strong interaction effects. The findings highlight the importance of model selection in survival analysis, especially in complex disease progression scenarios like HIV/AIDS.

Clinicopathological features and survival analysis of gastroenteropancreatic neuroendocrine neoplasms: a retrospective study in a single center of China

Objective： To investigate the clinicopathological features, survival and prognostic factors for gastroenteropancreatic neuroendocrine neoplasms（GEP-NENs） in a Chinese population.Methods： We investigated 154 consecutive patients（88 males, 66 females; median age 56 years, age range 9-86 years） diagnosed with GEP-NENs between 2001 and 2013 at The Affiliated Hospital of Qingdao University. Demographic, clinical and pathological variables and survival data were retrieved.Results： The pancreas was the most common site of involvement（63/154, 40.9%）. Tumor size varied from 0.3 to 16.0 cm（median, 1.2 cm）. The patients were followed up for a median period of 22 months（range, 1-157 months）. The estimated 3- and 5-year overall survival（OS） rates for all patients were 84.0% and 81.9%, respectively. Multivariate analysis showed that larger tumor size, lymphatic metastases and distant metastases were significant predictors for poor survival outcome.Conclusions： Our data provide further information on the clinicopathological features of GEP-NENs in China. Additionally, we identified tumor size, lymphatic metastases and distant metastases as independent prognostic factors for long-term survival.

Characteristics and dynamics analysis of Populus euphratica populations in the middle reaches of Tarim River

Populus euphratica Oliv. is widely distributed along the Tarim River. Maintaining stability of P. euphratica population is important to local development. This study explored the static life table, survivorship curves and four function curves (survival rate, cumulative mortality rate, mortality density, and hazard rate), and development index of P. euphratica population in the middle reaches of Tarim River. The results indicated that the age structure of P. euphratica population belonged to positive pyramidal type, which meant young age-class individuals occupied most populations. The number ofⅠ-Ⅱage classes accounted for 66.2% of whole population, and this indicated that there were abundant subsequent seedlings resources to support the growth of P. euphratica population in the middle reaches of Tarim River. The survivorship curve of P. euphratica belonged to the Deevey Ⅲ (concave-type) and the development index was 47.72%. Four function curves revealed that the individuals of P. euphratica sharply decreased at the initial stage and then leveled off at the late stage of survival curve. Time sequence prediction models predicted that the number of midlife individuals would increase in future 10, 20, 30 years, and P. euphratica population grew steadily as a result of rich saplings.

Hepatocellular carcinoma in extremely elderly patients:An analysis of clinical characteristics,prognosis and patient survival

AIM： To identify the clinical and prognostic features of patients with hepatocellular carcinoma （HCC） aged 80 years or more. METHODS： A total of 1310 patients with HCC were included in this study. Ninety-one patients aged 80 years or more at the time of diagnosis of HCC were defined as the extremely elderly group. Two hundred and thirty-four patients aged 〉/ 50 years but less than 60 years were regarded as the non-elderly group. RESULTS： The sex ratio （male to female） was significantly lower in the extremely elderly group （0.90：1） than in the non-elderly group （3.9：1, P〈 0.001）. The positive rate for HBsAg was significantly lower in the extremely elderly group and the proportion of patients negative for HBsAg and HCVAb obviously increased in the extremely elderly group （P〈 0.001）. There were no significant differences in the following parameters： diameter and number of tumors, Child-Pugh grading, tumor staging, presence of portal thrombosis or ascites, and positive rate for HCVAb. Extremely elderly patients did not often receive surgical treatment （P 〈 0.001） and they were more likely to receive conservative treatment （P〈 0.01）. There were no significant differences in survival curves based on the Kaplan-Meier methods in comparison with the overall patients between the two groups. However, the survival curves were significantly worse in the extremely elderly patients with stage Ⅰ/Ⅱ, stage Ⅰ/Ⅱ and Child-Pugh grade A cirrhosis in comparison with the non-elderly group. The causes of death did not differ among the patients, and most cases died of liverrelated diseases even in the extremely elderly patients. CONCLUSION： In the patients with good liver functions and good performance status, aggressive treatment for HCC might improve the survival rate, even in extremely elderly patients.

Clinicopathological analysis of paraganglioma with literature review

AIM： To investigate the 152 cases of paragangliomas resected over the past 32 years in West China Hospital dinicopathologically.METHODS： All cases of paragangliomas diagnosed at the Department of Gastrointestinal Surgery and Department of Pathology, West China Hospital, China were reviewed. The pathological documents were supplied by the Department of Pathology, West China Hospital, and other necessary data were extracted from the hospital records. The statistical analyses were performed by survival analysis （Kaplan-Meier method）, descriptive statistical analyses and Х^2 analysis.RESULTS： The neuroendocrine marker vimentin was found to be selectively expressed in the benign tumors, and there were significant differences in the expression of those markers in both benign and malignant tumors. The survival analysis revealed that survival correlated significantly with the malignancy, metastasis and nodal status.CONCLUSION： Vimentin may be useful in the differential diagnosis between malignant and benign tumors. The difference in the expression of this marker in the tumors could be a clue to the future clinical diagnosis. The malignancy, metastasis and the nodal status may predict the prognosis of this disease.