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Cervicogenic dizziness is dizziness triggered by movement or positioning of the cervical spine and is often accompanied by neck pain or stiffness. This is a prospective, pragmatic, assessor-blind, randomized controlled trial aimed at testing the efficacy and safety of adjuvant Chuna Manual Therapy (CMT) in patients with cervicogenic dizziness under usual care treatments. Fifty patients with cervicogenic dizziness will be randomly allocated to CMT or usual care (UC) groups in a 1 : 1 ratio. Extensive screening procedures, including examinations for central nervous system problems and nystagmus, will be applied to exclude other dizziness-inducing disorders. The eligible participants will receive 12 sessions of CMT plus UC or only UC over 6 weeks. CMT includes mandatory and discretionary techniques, whereas UC includes electrotherapy, thermotherapy, and patient education. The efficacy will be evaluated primarily as Dizziness Handicap Inventory score. The severity and frequency of dizziness, the level of neck pain or stiffness, and the cervical range of motion will also be evaluated. Safety will be assessed by adverse events. The data will be statistically analyzed at p<0.05. Trial Registration. This trial was registered with Clinical Research Information Service (CRIS) in Korea, KCT0002565, on 29 November 2017, https://cris.nih.go.kr/cris/search/search_result_st01_kren.jsp?seq=9610&ltype=&rtype=.

Alterations in mitochondrial respiration contribute to the development and progression of cancer via abnormal biogenesis, including generation of reactive oxygen species. Ubiquinol–cytochrome c reductase hinge protein (UQCRH) consists of the cytochrome bc1 complex serving respiration in mitochondria. In the present study, we analyzed UQCRH abnormalities in hepatocellular carcinoma (HCC) and its association with clinical outcomes of patients. UQCRH expression in HCC was determined via semiquantitative and quantitative real‐time reverse transcriptase polymerase chain reaction of 96 surgically resected HCC tissues positive for hepatitis B virus surface antigen. UQCRH was frequently overexpressed in HCC tissues (46.8%, based on 2.1‐fold cutoff). UQCRH overexpression was observed in HCCs with larger tumor size, poorer differentiation, or vascular invasion. Kaplan–Meier analysis revealed significantly shorter overall (P = 0.005) and recurrence‐free survival (P = 0.027) in patients with tumors overexpressing UQCRH. The prognostic impact of UQCRH was significant in subgroups of patients divided according to the α‐fetoprotein (AFP) level. The patient subgroup with higher AFP levels (≥20 ng/mL) exhibited significant differences in 5‐year overall (18.5% vs. 67.9%) and recurrence‐free survival rates (11.1% vs. 46.4%) between groups with and without UQCRH overexpression. In contrast, no marked survival differences were observed between subgroups with lower AFP levels (

Background and Aim Most prognostic models for hepatocellular carcinoma are based on data at the time of diagnosis. However, the disease frequently recurs or progresses after initial treatment, with changes in tumor burden and clinical status. Therefore, we developed a risk score model to predict survival of hepatocellular carcinoma patients at the time of disease recurrence or progression. Methods Of 1972 patients newly diagnosed with hepatocellular carcinoma at the National Cancer Center, Korea, between January 2004 and December 2009, 1301 with recurrent or progressive disease were enrolled. They were randomly classified into a development (75%, n = 976) and a validation cohort (25%, n = 325). A survival prediction method was established in the development cohort using the multivariate Cox proportional hazards model, and its performance was evaluated on the validation cohort. Results A model predicting survival of patients with recurrent or progressive hepatocellular carcinoma was developed using some known independent prognostic factors for overall survival: age, albumin, Model for End-Stage Liver Disease score, tumor burden, serum alpha-fetoprotein level, and presence of ascites. In addition, initial treatment modality and best response after initial treatment were also independent prognostic factors and were incorporated in the model. The C-statistics and χ2 statistics of this novel score for the validation cohort were 0.808 (95% CI: 0.781–0.834) and 4.408 for 3-year survival. Conclusions A new model to predict survival of patients with recurrent or progressive hepatocellular carcinoma was developed and validated. This model may be useful for planning subsequent treatments.

This study protocol aims to explore the effectiveness, safety, and cost-effectiveness of a herbal medication,Gongjindan(GJD), in patients with chronic dizziness. This will be a prospective, multicenter, randomized, double-blind, placebo-controlled, parallel-group, clinical trial. Seventy-eight patients diagnosed with Meniere’s disease, psychogenic dizziness, or dizziness of unknown cause will be randomized and allocated to either a GJD or a placebo group in a 1 : 1 ratio. Participants will be orally given 3.75 g GJD or placebo in pill form once a day for 56 days. The primary outcome measure will be the Dizziness Handicap Inventory score. Secondary outcome measures will be as follows: severity (mean vertigo scale and visual analogue scale) and frequency of dizziness, balance function (Berg Balance Scale), fatigue (Fatigue Severity Scale) and deficiency pattern/syndrome (qi blood yin yang-deficiency questionnaire) levels, and depression (Korean version of Beck’s Depression Inventory) and anxiety (State-Trait Anxiety Inventory) levels. To assess safety, adverse events, including laboratory test results, will be monitored. Further, the incremental cost-effectiveness ratio will be calculated based on quality-adjusted life years (from the EuroQoL five dimensions’ questionnaire) and medical expenses. Data will be statistically analyzed at a significance level of 0.05 (two-sided). This trial is registered with ClinicalTrials.govNCT03219515, in July 2017.

PURPOSE The objective of this study is to evaluate the relationship of atheroembolic risk factors with postoperative recovery of renal function after on-clamp partial nephrectomy (PN) with warm ischemia in patients with staged T1-2 renal cell carcinoma (RCC). MATERIALS AND METHODS A total of 234 patients from 2004 to 2012 were included, and their clinicopathologic and operative parameters, including atheroembolic risk factors were reviewed retrospectively. Renal function, as determined by estimated glomerular filtration rate (eGFR) and measurement of serum creatinine level (Cr) at each scheduled follow-up for a median four years, was compared between the high-risk (HR) group (n=49, ≥ five risk factors) and the low-risk (LR) group (n=185, < five risk factors). RESULTS Except for baseline renal function and number of risk factors for atheroembolism, differences in characteristics between groups were comparatively insignificant. At 3 months after the operation, Cr and eGFR differed significantly between the two groups (p < 0.05), but no differences were observed afterward. Significant deterioration from baseline in Cr and eGFR was observed in both groups at 1 month after the operation, with a greater change in the HR group (p < 0.05). From measurement to measurement, significantly faster deterioration in Cr and eGFR was observed in the HR group than in the LR group until 6 months after the operation (Cr: LR, 0.02 mg/dL and HR, 0.13 mg/dL; eGFR: LR, 1.50 mL/min/1.73 m(2) and HR, 6.38 mL/min/1.73 m(2); p < 0.05). CONCLUSION The presence of atheroembolic risk factors may negatively influence postoperative recovery of renal function after PN in patients with localized RCC.

The purpose of this study is the evaluation of the surgical and oncological results of laparoscopic liver resection (LLR) for hepatocellular carcinoma (HCC) by comparing laparoscopic and open liver resection (OLR) in the treatment of this disease. Retrospective analysis of laparoscopic and OLR for HCC (

Background and Aims To evaluate the clinical outcomes of patients with hepatocellular carcinoma (HCC) and compare the findings with that of a previous cohort. Methods Overall, 1972 HCC patients diagnosed and treated at the National Cancer Center, Korea between 2004 and 2009 were enrolled. The data of this cohort were compared with those of a previous cohort (2000–2003) from the same institution. Results In all (mean age, 56.4 years; 1642 men), 74.6% was hepatitis B virus (HBV) positive, 81.6% were Child–Pugh (CP) class A, and 64.4% was Barcelona Clinic Liver Cancer (BCLC) stage C. The modified Union for International Cancer Control (mUICC) stage I, II, III, IVa, and IVb was found in 8.9%, 29.6%, 24.8%, 23.1%, and 13.6% patients, respectively. The most common initial treatment was transarterial chemotherapy (58.3%), followed by resection (18.6%). The 5-year survival rate of BCLC stage 0, A, B, and C were 79.6%, 67.2%, 33.9%, and 17.1%, respectively. The performance status, BCLC stage, mUICC stage, CP class, model for end-stage liver disease score, tumor characteristics, portal vein tumor invasion, and serum alpha-fetoprotein level proved to be independent prognostic variables. Overall survival in the present cohort was better than that in the previous cohort (hazard ratio, 0.829; 95% confidence interval, 0.754–0.912), especially for advanced HCC patients with HBV-positive status. Conclusions This cohort study provides valuable insights into the characteristics of HCC in Korean patients. Our findings may help develop clinical trials, treatment strategies, and prognosis systems for HCC patients in HBV-endemic areas.

To validate the Memorial Sloan-Kettering Cancer Center (MSKCC) and Heng models with metastatic renal cell carcinoma treated with sunitinib, and to investigate prognostic factors in these patients. This study included 106 patients with metastatic renal cell carcinoma who were treated with sunitinib from April 2007 to July 2012 including 35 patients who received systemic treatment before sunitinib and 71 that were naive to systemic treatment. Patients were evaluated using the MSKCC and Heng models, and the significance of several prognostic factors were evaluated. The application of the MSKCC and Heng risk criteria resulted in stratification into 3 groups (favorable, intermediate, and poor risk) with distinctly different overall survival (OS) curves (P

Most prognostic models for hepatocellular carcinoma are based on data at the time of diagnosis. However, the disease frequently recurs or progresses after initial treatment, with changes in tumor burden and clinical status. Therefore, we developed a risk score model to predict survival of hepatocellular carcinoma patients at the time of disease recurrence or progression.Of 1972 patients newly diagnosed with hepatocellular carcinoma at the National Cancer Center, Korea, between January 2004 and December 2009, 1301 with recurrent or progressive disease were enrolled. They were randomly classified into a development (75%, n = 976) and a validation cohort (25%, n = 325). A survival prediction method was established in the development cohort using the multivariate Cox proportional hazards model, and its performance was evaluated on the validation cohort.A model predicting survival of patients with recurrent or progressive hepatocellular carcinoma was developed using some known independent prognostic factors for overall survival: age, albumin, Model for End-Stage Liver Disease score, tumor burden, serum alpha-fetoprotein level, and presence of ascites. In addition, initial treatment modality and best response after initial treatment were also independent prognostic factors and were incorporated in the model. The C-statistics and χA new model to predict survival of patients with recurrent or progressive hepatocellular carcinoma was developed and validated. This model may be useful for planning subsequent treatments.

Objectives: Chronic hepatitis B virus (HBV) infection is the most common cause of hepatocellular carcinoma (HCC) in South Korea, but a high prevalence of metabolic diseases may result in increases in the incidence of cryptogenic HCC (cHCC). We studied characteristics of the cHCC in a single-center cohort. Methods: A cohort of 1,784 HCC patients newly diagnosed and treated at the National Cancer Center, Korea, between 2004 and 2009 was reviewed and analyzed. Results: The cause of HCC was categorized as cHCC, HBV, hepatitis C virus (HCV), or alcohol. Overall, 162 (9.1%) patients of the HCC cohort had cHCC, and their mean age was 61.9 years. The median survival of cHCC patients was 24.7 months, which was the second shortest among the four groups after HBV HCC. cHCC patients had the largest tumor size (mean 7.4 cm) and the second highest proportion of poor prognostic factors such as the proportion of poorly defined tumors and extrahepatic spread in imaging studies. cHCC patients had better survival than HBV HCC patients according to multivariate analysis. Among cHCC patients, 137 (84.6%) had anti-HBc IgG antibodies, but this sub-group had different clinical features to those of HBV HCC patients. The body mass index (BMI) and hyperglycemia and hypercholesterolemia levels in cHCC patients were similar to those in HCV and alcoholic HCC patients. Conclusions: Anti-HBc IgG antibodies were present in most cHCC patients, but cHCC patients had better survival than HBV HCC patients on multivariate analysis. However, cHCC patients had a larger mean tumor size and more aggressive tumor characteristics than HCV HCC or alcoholic HCC patients did. It is hoped that this study will contribute to a better understanding of cHCC in HBV-endemic areas.

This pilot multicentered, randomized, parallel, sham-controlled trial is intended to evaluate the effectiveness and safety of electroacupuncture therapy for poststroke patients with urinary incontinence. Forty stroke survivors aged >19 years will be recruited in 2 hospitals in the Republic of Korea. Patients who experienced stroke within 2 years and satisfy criteria of urinary frequencies ≥2 with either 3 to 4 points on the Patient Perception of Intensity of Urgency Scale or 13 points or more on the Korean version of the International Prostate Symptom Scale (K-IPSS) will be identified, along with other eligibility criteria. Patients will be randomly allocated to either a treatment or control group to receive 10 sessions of electroacupuncture or sham therapies, respectively. Patients and outcome assessors will be blinded. The primary outcome is the change of Total Urgency and Frequency Score between the baseline and the trial endpoint. The K-IPSS, the International Consultation on Incontinence Questionnaire for Urinary Incontinence Short Form, and the Lower Urinary Tract Symptoms Outcome Score will be evaluated for effectiveness assessment. Adverse events will be reported after every session. The Blinding Index will also be calculated. Data will be statistically analyzed with 0.05 significance levels by 2-sided testing.

The response criteria for complete remission (CR) in acute myeloid leukemia (AML) are currently based on morphology and blood cell counts. However, these criteria are insufficient to establish a diagnosis in cases with poor quality bone marrow (BM) samples demonstrating a loss of cellular morphology. We investigated whether the sera of patients contained biomarkers that indicate disease response status. First, we performed multidimensional liquid chromatography-differential gel electrophoresis (MDLC-DIGE) to generate protein profiles of two pooled, paired serum samples from patients who had achieved CR; one collected at diagnosis (PreCR) and the other collected after chemotherapy (CR). Then, with the biomarker candidates found, ELISA was carried out for individual PreCR and CR samples, and for other verification sets including nonremission (NR) patients and normal samples. We selected two proteins, complement factor H (CFH) and apolipoprotein H (ApoH), with dye (Cy) ratios showing greater than 2.0-fold differences between the pooled samples. ELISA showed that CFH and ApoH are useful for distinguishing between the recovered (CR and normal) and nonrecovered (PreCR, PreNR, and NR) states in AML (p

PURPOSE Tumor regression grade (TRG) is predictive of therapeutic response in rectal cancer patients after chemoradiotherapy (CRT) followed by curative resection. However, various TRG systems have been suggested, with subjective categorization, resulting in interobserver variability. This study compared the prognostic validity of four different TRG systems in order to identify the most ideal TRG system. MATERIALS AND METHODS This study included 933 patients who underwent preoperative CRT and curative resection. Primary tumors alone were graded according to the American Joint Committee on Cancer (AJCC), Dworak, and Ryan TRG systems, and both primary tumors and regional lymph nodes were graded according to a modified Dworak TRG system. The ability of each TRG system to predict recurrence-free survival (RFS) and overall survival (OS) was analyzed using chi-square and C statistics. RESULTS All four TRG systems were significantly predictive of both RFS and OS (p < 0.001 each), however none was a better predictor of prognosis than ypStage. Among the four TRGs, the mDworak TRG system was a better predictor of RFS and OS than the AJCC, Dworak, and Ryan TRG systems, and both the chi-square and C statistics were higher for the former, although the differences were not statistically significant. The combination of ypStage and the modified Dworak TRG better predicted RFS and OS than ypStage alone. CONCLUSION The modified Dworak TRG system for evaluation of entire tumors including regional lymph nodes is a better predictor of survival than current TRG systems for evaluation of the primary tumor alone.

Background and Aim A model to estimate survival in ambulatory hepatocellular carcinoma patients (MESIAH) is useful for estimating patient prognosis but needs improvement for Korean patients, most of whom have a hepatitis B virus. We aimed to modify the MESIAH for better prognostication through enhancing calibration for Korean patient population (K-MESIAH). Methods Utilizing a cohort of 1,969 hepatocellular carcinoma (HCC) patients from the National Cancer Center of Korea between 2004 and 2009, a survival prediction model was developed using the Cox proportional hazards model. The model’s performance was evaluated using C-statistical and χ2-statistical analyses. External validation was performed using an independent cohort of 328 patients from the Seoul National University Bundang Hospital. Results To develop the K-MESIAH, etiology was added to the original risk factors (age, Model for Endstage Liver Disease, albumin, size of the largest nodule, number of tumor nodules, vascular invasion, metastasis, and alpha fetoprotein) in the MESIAH. From the internal validation study, the C-statistics and χ2-statistics for one-, three-, and five-years of survival were 0.83 (95% Confidence Interval: 0.82−0.85), 49.07; 0.81 (95% Confidence Interval: 0.79−0.82), 28.95; and 0.80 (95% Confidence Interval: 0.79−0.81), 20.93, respectively. The K-MESIAH also showed a high prediction ability for the external validation cohort. Conclusions A survival prediction model for Korean HCC patients was developed and validated to have a high level of performance. This K-MESIAH may be more useful in clinical practice and personalized care in a hepatitis B virus endemic area.

Background Despite the recent identification of several prognostic gene signatures, the lack of common genes among experimental cohorts has posed a considerable challenge in uncovering the molecular basis underlying hepatocellular carcinoma (HCC) recurrence for application in clinical purposes. To overcome the limitations of individual gene-based analysis, we applied a pathway-based approach for analysis of HCC recurrence. Results By implementing a permutation-based semi-supervised principal component analysis algorithm using the optimal principal component, we selected sixty-four pathways associated with hepatitis B virus (HBV)-positive HCC recurrence (p

To compare the diagnostic performance of digital tomosynthesis (DTS) and chest radiography for detecting airway abnormalities, using computed tomography (CT) as a reference. We evaluated 161 data sets from 149 patients (91 with and 70 without airway abnormalities) who had undergone radiography, DTS, and CT to detect airway problems. Radiographs and DTS were evaluated to localize and score the severity of the airway abnormalities, and to score the image quality using CT as a reference. Receiver operating characteristics (ROC), McNemar’s test, weighted kappa, and the paired t-test were used for statistical analysis. The sensitivity of DTS was higher (reader 1, 93.51 %; reader 2, 94.29 %) than chest radiography (68.83 %; 71.43 %) in detecting airway lesions. The diagnostic accuracy of DTS (90.91 %; 94.70 %) was also significantly better than that of radiography (78.03 %; 82.58 %, all p

Objectives The aim of this study was to investigate the expression of two commonly altered genes ERG and PTEN in prostate cancer (PC) and evaluate their prognostic significance. Despite conflicting published results, TMPRSS2-ERG gene fusion and PTEN loss are generally considered unfavorable markers for PC progression. Materials and Methods Of the 762 prostatic adenocarcinoma specimens obtained from radical prostatectomy, 613 without neoadjuvant hormone therapy were included in tissue microarrays for quantitatively assessment of ERG and PTEN expression via immunohistochemistry. Statistical analysis of the association between such expression and clinicopathological parameters, including clinical prognosis, was performed with a p-value of = 10 ng/mL), Gleason score (>6), pathologic T stage (>= T3), positive surgical margin, and extraprostatic capsule extension as significant risk factors for BCR (p

OBJECTIVE We report on the short and late morbidity and mortality of ileal conduit and neobladder after radical cystectomy with their associated risk factors. METHODS We retrospectively collected data on 308 non-metastatic bladder cancer patients who underwent radical cystectomy with either ileal conduit or neobladder for a curative intent from January 1999 to December 2011. Post-operative morbidity and mortality of 30-day (early) and 90-day (late) complication with their risk factors were examined in association with different types of urinary diversion. A comparative analysis using propensity-score matching was performed with matching variables of age, sex, number of underlying diseases and pathologic T and N stages, lymph node dissection, operative time and time of surgical year for comparison of the early and late morbidities between ileal conduit and neobladder. RESULTS During the median follow-up of 46.6 months, early and late morbidities were 29.5% (n=91) and 19.8% (n=61), and complication-related mortalities were 2.2 and 6.6%, respectively. The type of urinary diversion significantly affected only the late complications (early: neobladder 57 vs. ileal conduit 47, P=0.096; late: neobladder 67 vs. ileal conduit 37, P

To evaluate the clinical outcomes of patients with hepatocellular carcinoma (HCC) and compare the findings with that of a previous cohort.Overall, 1972 HCC patients diagnosed and treated at the National Cancer Center, Korea between 2004 and 2009 were enrolled. The data of this cohort were compared with those of a previous cohort (2000-2003) from the same institution.In all (mean age, 56.4 years; 1642 men), 74.6% was hepatitis B virus (HBV) positive, 81.6% were Child-Pugh (CP) class A, and 64.4% was Barcelona Clinic Liver Cancer (BCLC) stage C. The modified Union for International Cancer Control (mUICC) stage I, II, III, IVa, and IVb was found in 8.9%, 29.6%, 24.8%, 23.1%, and 13.6% patients, respectively. The most common initial treatment was transarterial chemotherapy (58.3%), followed by resection (18.6%). The 5-year survival rate of BCLC stage 0, A, B, and C were 79.6%, 67.2%, 33.9%, and 17.1%, respectively. The performance status, BCLC stage, mUICC stage, CP class, model for end-stage liver disease score, tumor characteristics, portal vein tumor invasion, and serum alpha-fetoprotein level proved to be independent prognostic variables. Overall survival in the present cohort was better than that in the previous cohort (hazard ratio, 0.829; 95% confidence interval, 0.754-0.912), especially for advanced HCC patients with HBV-positive status.This cohort study provides valuable insights into the characteristics of HCC in Korean patients. Our findings may help develop clinical trials, treatment strategies, and prognosis systems for HCC patients in HBV-endemic areas.

Introduction There is no reliable screening tool to identify people with high risk of developing pancreatic cancer even though pancreatic cancer represents the fifth-leading cause of cancer-related death in Korea. The goal of this study was to develop an individualized risk prediction model that can be used to screen for asymptomatic pancreatic cancer in Korean men and women. Materials and Methods Gender-specific risk prediction models for pancreatic cancer were developed using the Cox proportional hazards model based on an 8-year follow-up of a cohort study of 1,289,933 men and 557,701 women in Korea who had biennial examinations in 1996-1997. The performance of the models was evaluated with respect to their discrimination and calibration ability based on the C-statistic and Hosmer-Leme show type chi(2) statistic. Results A total of 1,634 (0.13%) men and 561 (0.10%) women were newly diagnosed with pancreatic cancer. Age, height, BMI, fasting glucose, urine glucose, smoking, and age at smoking initiation were included in the risk prediction model for men. Height, BMI, fasting glucose, urine glucose, smoking, and drinking habit were included in the risk prediction model for women. Smoking was the most significant risk factor for developing pancreatic cancer in both men and women. The risk prediction model exhibited good discrimination and calibration ability, and in external validation it had excellent prediction ability. Conclusion Gender-specific risk prediction models for pancreatic cancer were developed and validated for the first time. The prediction models will be a useful tool for detecting high-risk individuals who may benefit from increased surveillance for pancreatic cancer.

The response criteria for complete remission (CR) in acute myeloid leukemia (AML) are currently based on morphology and blood cell counts. However, these criteria are insufficient to establish a diagnosis in cases with poor quality bone marrow (BM) samples demonstrating a loss of cellular morphology. We investigated whether the sera of patients contained biomarkers that indicate disease response status. First, we performed multidimensional liquid chromatography-differential gel electrophoresis (MDLC-DIGE) to generate protein profiles of two pooled, paired serum samples from patients who had achieved CR; one collected at diagnosis (PreCR) and the other collected after chemotherapy (CR). Then, with the biomarker candidates found, ELISA was carried out for individual PreCR and CR samples, and for other verification sets including nonremission (NR) patients and normal samples. We selected two proteins, complement factor H (CFH) and apolipoprotein H (ApoH), with dye (Cy) ratios showing greater than 2.0-fold differences between the pooled samples. ELISA showed that CFH and ApoH are useful for distinguishing between the recovered (CR and normal) and nonrecovered (PreCR, PreNR, and NR) states in AML (p0.001). We successfully applied a protein profiling technology of MDLC-DIGE and LC-MS/MS to discover two biomarkers for CR which needs further validation for a clinical setting.

Gene expression data can be associated with various clinical outcomes. In particular, these data can be of importance in discovering survival-associated genes for medical applications. As alternatives to traditional statistical methods, sophisticated methods and software programs have been developed to overcome the high-dimensional difficulty of microarray data. Nevertheless, new algorithms and software programs are needed to include practical functions such as the discovery of multiple sets of survival-associated genes and the incorporation of risk factors, and to use in the R environment which many statisticians are familiar with. For survival modeling with microarray data, we have developed a software program (called rbsurv) which can be used conveniently and interactively in the R environment. This program selects survival-associated genes based on the partial likelihood of the Cox model and separates training and validation sets of samples for robustness. It can discover multiple sets of genes by iterative forward selection rather than one large set of genes. It can also allow adjustment for risk factors in microarray survival modeling. This software package, the rbsurv package, can be used to discover survival-associated genes with microarray data conveniently.

4045 Background: Due to the very low survival of pancreatic cancer (PC), early detection is a critical strategy to improve the outcome of PC.Screening individuals with genetic syndromes associated with a high incidence of PC or families predisposed to PC is increasing. However, those populations account for only 10% of all PC cases. A different approach for developing an effective surveillance tool is needed to identify high-risk individuals without hereditary risks. The goal of this study was to develop and validate risk prediction models for filtering purposes as part of the sporadic PC surveillance activities. Methods: Based on an eight-year follow-up of a cohort study involving 1,289,933 men and 557,701 women in Korea who had biennial examinations in 1996-1997, gender-specific risk prediction models were developed using the Cox proportional hazards model. The models were validated using independent data of 500,046 men and 627,629 women who had biennial examinations in 1998-1999. The models’ performance was evaluated with respect to their discrimination and calibration abilities based on the C-statistic and the Hosmer-Lemeshow (H-L) type χ2-statistic. Results: Age, height, BMI, fasting glucose, urine glucose, smoking, and age at smoking initiation were included in the model for men. In the model for women, height, BMI, fasting glucose, urine glucose, smoking, and drinking habits were included. Smoking was the most significant risk factor for developing pancreatic cancer in both men and women. Model validation showed excellent model performance with C-statistics (95% confidence interval) of 0.813 (0.800−0.826) and 0.804 (0.788−0.820) for men and women, respectively. The H-L type χ2-statistics (P-values) were 7.478 (0.587) and 10.297 (0.327) for men and women, respectively. Five different risk groups could be identified with hazard ratios (HR) greater than 20 in the highest risk group compared to the lowest risk group in both the men and women. Conclusions: Gender-specific individualized risk prediction models for PC were developed and validated with a high level of performance. These models can be used to identify high-risk individuals who may benefit from increased surveillance of PC.