• 제목/요약/키워드: Meier method

검색결과 328건 처리시간 0.031초

Jackknife Estimator of Logistic Transformation from Truncated Data

  • Lee, Won-Hyung
    • 한국국방경영분석학회지
    • /
    • 제6권2호
    • /
    • pp.129-149
    • /
    • 1980
  • In medical follow-up, equipment lifetesting, various military situations, and other fields, one often desires to calculate survival probability as a function of time, p(t). If the observer is able to record the time of occurrence of the event of interest (called a 'death'), then an empirical, non-parametric estimate may simply by obtained from the fraction of survivors after various elapsed times. The estimation is more complicated when the data are truncated, i.e., when the observer loses track of some individuals before death occurs. The product-limit method of Kaplan and Meier is one way of estimating p(t) when the mechanism causing truncation is independent of the mechanism causing death. This paper proposes jackknife estimators of logistic trans-formation and compares it to the product-limit method. A computer simulation is used to generate the times of death and truncation from a variety of assumed distributions.

  • PDF

Racial and Social Economic Factors Impact on the Cause Specific Survival of Pancreatic Cancer: A SEER Survey

  • Cheung, Rex
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권1호
    • /
    • pp.159-163
    • /
    • 2013
  • Background: This study used Surveillance, Epidemiology and End Results (SEER) pancreatic cancer data to identify predictive models and potential socio-economic disparities in pancreatic cancer outcome. Materials and Methods: For risk modeling, Kaplan Meier method was used for cause specific survival analysis. The Kolmogorov-Smirnov's test was used to compare survival curves. The Cox proportional hazard method was applied for multivariate analysis. The area under the ROC curve was computed for predictors of absolute risk of death, optimized to improve efficiency. Results: This study included 58,747 patients. The mean follow up time (S.D.) was 7.6 (10.6) months. SEER stage and grade were strongly predictive univariates. Sex, race, and three socio-economic factors (county level family income, rural-urban residence status, and county level education attainment) were independent multivariate predictors. Racial and socio-economic factors were associated with about 2% difference in absolute cause specific survival. Conclusions: This study s found significant effects of socio-economic factors on pancreas cancer outcome. These data may generate hypotheses for trials to eliminate these outcome disparities.

Increased Argonaute 2 Expression in Gliomas and its Association with Tumor Progression and Poor Prognosis

  • Feng, Bo;Hu, Peng;Lu, Shu-Jun;Chen, Jin-Bo;Ge, Ru-Li
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권9호
    • /
    • pp.4079-4083
    • /
    • 2014
  • Background: Previous studies have showed that argonaute 2 is a potential factor related to genesis of several cancers, however, there have been no reports concerning gliomas. Methods: Paraffin specimens of 129 brain glioma cases were collected from a hospital affiliated to Binzhou Medical University from January 2008 to July 2013. We examined both argonaute 2 mRNA and protein expression by real-time quantitative PCR (qRT-PCR), Western blot analysis, and immunohistochemistry (IHC). The survival curves of the patients were determined using the Kaplan-Meier method and Cox regression, and the log-rank test was used for statistical evaluations. Results: Both argonaute 2 mRNA and protein were upregulated in high-grade when compared to low-grade tumor tissues. Multivariate analysis revealed that argonaute 2 protein expression was independently associated with the overall survival (HR=4.587, 95% CI: 3.001-6.993; P=0.002), and that argonaute 2 protein expression and WHO grading were independent prognostic factors for progression-free survival (HR=4.792, 95% CI: 3.993-5.672; P<0.001, and HR=2.109, 95% CI: 1.278-8.229; P=0.039, respectively). Kaplan-Meier analysis with the log-rank test indicated that high argonaute 2 protein expression had a significant impact on overall survival (P=0.0169) and progression-free survival (P=0.0324). Conclusions: The present study showed that argonaute 2 expression is up-regulated in gliomas. Argonaute 2 might also serve as a novel prognostic marker.

Prognostic Significance of α5β1-integrin Expression in Cervical Cancer

  • Wang, Hua-Yi;Chen, Zhe;Wang, Zhu-Hui;Wang, Hong;Huang, Li-Ming
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권6호
    • /
    • pp.3891-3895
    • /
    • 2013
  • The purpose of this study was to evaluate the association of expression of ${\alpha}5{\beta}1$-integrin with clinicopathologic features and prognosis in cervical cancer. Levels of ${\alpha}5{\beta}1$-integrin in normal cervical mucosa and cervical cancer tissue were detected with immunohistochemistry. Survival analysis by the Kaplan-Meier method was performed to assess prognostic significance. ${\alpha}5{\beta}1$-integrin expression was detected in 84.6% (143/169) cervical cancer samples, significantly different from that in normal cervical mucosa (P < 0.05). Positive expression rates of ${\alpha}5{\beta}1$-integrin in patients with poor histologic differentiation, lymph node metastasis, and recurrence were elevated. Using Kaplan-Meier analysis, a comparison of survival curves of low versus high expression of ${\alpha}5{\beta}1$-integrin revealed a highly significant difference in human cervical cancer cases (P < 0.05), suggesting that overexpression of ${\alpha}5{\beta}1$-integrin is associated with a worse prognosis.The ${\alpha}5{\beta}1$-integrin promotes angiogenesis and associates with lymph node metastasis, vascular invasion and poor prognosis of cervical cancer. The current study indicated that ${\alpha}5{\beta}1$-integrin may be an independent prognostic factor for cervical cancer patients.

전이암 환자에서 단일기관 영양검색 도구의 예후 가치 (Prognostic Value of a Single Center Nutrition Screening Tool in Patients with Metastatic Cancer)

  • 윤성수;김민진;김은혜;이지영;윤성우
    • 대한암한의학회지
    • /
    • 제24권2호
    • /
    • pp.1-11
    • /
    • 2019
  • Objectives : We investigated whether a single center nutrition screening tool (Kyunghee Neo Nutrition Risk Screening, KNNRS) can predict survival in patients with metastatic cancer. Methods : We retrospectively reviewed data of inpatients with metastatic cancer from April 2016 to August 2019. Data on demographic and clinical parameters were collected from electronic medical records, and overall survival was estimated using the Kaplan-Meier method. Stepwise Cox regression analysis was used to determine factors associated with survival. Patients with a KNNRS score of 0 to 3 were classified as "no-risk", 4 to 10 as "low-risk", and 11 to 20 as "high-risk". Results : Total 105 patients were included in the study. According to nutritional screening at baseline, 25 patients (23.8%, median age 57.0) were classified as ""no risk"" group; 80 patients (76.2%, median age 68.5) as "low risk" group; No patients as "high risk" group. Predictors of survival were Eastern Cooperative Oncology Group Performance Status score of 3 or 4 (hazard ratio [HR] = 1.93; 95% confidence interval [CI] = 1.21-3.10), hemoglobin less than 10 g/dL (HR = 1.97; 95% CI = 1.25-3.10) and C-reactive protein more than 1.0 mg/dL (HR = 1.95; 95% CI = 1.21-3.13). Kaplan-Meier survival analysis showed significant differences in the survival between KNNRS groups: ""no risk"" group: 6.1 ± 1.4 months (95% CI = 3.37-8.83); ""low risk"" group: 3.4 ± 0.9 months (95% CI = 1.5-5.37). Conclusions : Nutritional status according to KNNRS wasn't significant predictor of survival for patients with metastatic cancer. Improvement of KNNRS score thresholds is needed.

Expression of microRNA-218 and its Clinicopathological and Prognostic Significance in Human Glioma Cases

  • Cheng, Mao-Wei;Wang, Ling-Ling;Hu, Gu-Yu
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권5호
    • /
    • pp.1839-1843
    • /
    • 2015
  • Background: MicroRNAs are a class of noncoding RNAs which regulate multiple cellular processes during tumor development. The purpose of this report is to investigate the clinicopathological and prognostic significance of miR-218 in human gliomas. Materials and Methods: Quantitative RT-PCR (qRT-PCR) was conducted to detect the expression of miR-218 in primary normal human astrocytes, three glioma cell lines and 98 paired glioma and adjacent normal brain tissues.Associations of miR-218 with clinicopathological variables of glioma patients were statistically analyzed. Finally, a survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model. Results: The expression level of miR-218 in primary normal human astrocytes was significantly higher than that in glioma cell lines (p<0.01). Also, the expression level of miR-218 in glioma tissues was significantly downregulated in comparison with that in the adjacent normal brain tissues (p<0.001). Statistical analyses demonstrated that low miR-218 expression was closely associated with advanced WHO grade (p=0.002) and low Karnofsky performance score (p=0.010) of glioma patients. Kaplan-Meier analysis with the log-rank test showed that patients with low-miR-218 expression had poorer disease-free survival and overall survival (p=0.0045 and 0.0124, respectively). Multivariate analysis revealed that miR-218 expression was independently associated with the disease-free survival (p=0.009) and overall survival (p=0.004) of glioma patients. Conclusions: Our results indicate that miR-218 is downregulated in gliomas and that its status might be a potential valuable biomarker for glioma patients.

Expression and Prognostic Significance of lncRNA MALAT1 in Pancreatic Cancer Tissues

  • Liu, Jiang-Hua;Chen, Gang;Dang, Yi-Wu;Li, Chun-Jun;Luo, Dian-Zhong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권7호
    • /
    • pp.2971-2977
    • /
    • 2014
  • Background: Long non-coding RNAs (lncRNAs) have been recently observed in various human cancers. However, the role of lncRNAs in pancreatic duct adenocarcinoma (PDAC) remains unclarified. The aim of this study was to detect the expression of lncRNA MALAT1 in PDAC formalin-fixed, paraffin embedded (FFPE) tissues and to investigate the clinical significance of the MALAT1 level. Methods: The expression of MALAT1 was examined in 45 PDAC and 25 adjacent non-cancerous FFPE tissues, as well as in five PDAC cell lines and a normal pancreatic epithelium cell line HPDE6c-7, using qRT-PCR. The relationship between MALAT1 level and clinicopathological parameters of PDAC was analyzed with the Kaplan-Meier method and Cox proportional hazards model. Results: The relative level of MALAT1 was significantly higher in PDAC compared to the adjacent normal pancreatic tissues (p=0.009). When comparing the MALAT1 level in the cultured cell lines, remarkably higher expression of MALAT1 was found in aspc-1 PDAC cells compared with the immortal pancreatic duct epithelial cell line HPDE6c-7 (q=7.573, p<0.05). Furthermore, MALAT1 expression level showed significant correlation with tumor size (r=0.35, p=0.018), tumor stage (r=0.439, p=0.003) and depth of invasion (r=0.334, p=0.025). Kaplan-Meier analysis revealed that patients with higher MALAT1 expression had a poorer disease free survival (p=0.043). Additionally, multivariate analysis indicated that overexpression of MALAT1, as well as the tumor location and nerve invasion, was an independent predictor of disease-specific survival of PDAC. Conclusion: MALAT1 might be considered as a potential prognostic indicator and may be a target for diagnosis and gene therapy for PDAC.

DEP Domain Containing 1 is a Novel Diagnostic Marker and Prognostic Predictor for Hepatocellular Carcinoma

  • Yuan, Sheng-Guang;Liao, Wei-Jia;Yang, Jian-Jun;Huang, Guo-Jin;Huang, Zhao-Quan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권24호
    • /
    • pp.10917-10922
    • /
    • 2015
  • Background: This study was conducted to determine DEPDC1 expression in hepatocelluar carcinomas (HCCs) and to reveal its potential role in diagnosis and prognosis of affected patients. Materials and Methods: DEPDC1 expression at the mRNA level was detected by quantitative real-time PCR (qRT-PCR) in 205 cases of HCC and paired adjacent normal liver tissues, and by semi-quantitative RT-PCR in 20 cases. Survival curves were obtained by using Kaplan-Meier method and Log-rank test. Independent predictors associated with regard to disease free survival (DFS) and overall survival (OS) were identified using the Cox proportional hazard model. Results: High DEPDC1 mRNA levels were detected in 144 out of 205 cases (70.24%) of HCC, significantly associated with clinicopathological parameters, including tumor size (${\geq}4cm$), alpha-fetoprotein (${\geq}100ng/ml$), B-C of BCLC stage and recurrence. Kaplan-Meier survival analysis revealed that HCC patients with high DEPDC1 expression had poor OS and DFS. Multivariate analysis demonstrated that high DEPDC1 expression was an independent predictor for OS (HR=1.651; 95% 95%CI, 1.041-2.617; p=0.033) and DFS (HR=1.583; 95%CI, 1.01-2.483; p=0.045). Conclusions: Our results indicate DEPDC1 might be a novel diagnostic marker and an independent prognostic predictor for HCC patients.

상악암에 대한 집합적 치료 (Multidisciplinary Treatment for Maxillary Cancer)

  • 조재식;김성훈;박은호;이종원
    • 대한기관식도과학회:학술대회논문집
    • /
    • 대한기관식도과학회 1993년도 제27차 학술대회 초록집
    • /
    • pp.95-95
    • /
    • 1993
  • 상악암은 비교적 진행되어서야 발견되는 수가 많지만 경부 임파절 전이나 원격 전이는 다른 두경부 암에 비해 흔하지 않기 때문에 종양의 국소 억제가 치료의 성패를 좌우하게 된다. 그러나, 상악동은 안와나 두개저에 접하고 있어서 다른 악성 종양처럼 충분하게 안전한 절제연을 두고 제거하는 것이 불가능한 수가 많다. 한편 대부분의 시설에서 수술과 방사선요법을 단독 또는 병행요법으로 시행하고 있는데 그 치료성적이 보고자에 따라 다양하며 비교적 좋지 못한 형편이다. 저자들은 88년 t월부터 91년 12월까지 상악암으로 진단받고 동맥내 항암제 주입요법, 방사선 치료및 수술을 포함한 집합적 치료를 시행하였던 16례(전례 편평상피암, T2 1례, T3 6례, T4 9례, 평균 연령 57.2세)에 대하여 그 결과를 후향적으로 검토하였다. Kaplan-Meier법에 의한 5년 생존률은 51.95%였으며 안구나 구개, 안면 피부등을 일부 보존할 수 있었고 기능적으로도 만족할 만하였다.

  • PDF

Prognostic Value of an Immune Long Non-Coding RNA Signature in Liver Hepatocellular Carcinoma

  • Rui Kong;Nan Wang;Chun li Zhou;Jie Lu
    • Journal of Microbiology and Biotechnology
    • /
    • 제34권4호
    • /
    • pp.958-968
    • /
    • 2024
  • In recent years, there has been a growing recognition of the important role that long non-coding RNAs (lncRNAs) play in the immunological process of hepatocellular carcinoma (LIHC). An increasing number of studies have shown that certain lncRNAs hold great potential as viable options for diagnosis and treatment in clinical practice. The primary objective of our investigation was to devise an immune lncRNA profile to explore the significance of immune-associated lncRNAs in the accurate diagnosis and prognosis of LIHC. Gene expression profiles of LIHC samples obtained from TCGA database were screened for immune-related genes. The optimal immune-related lncRNA signature was built via correlational analysis, univariate and multivariate Cox analysis. Then, the Kaplan-Meier plot, ROC curve, clinical analysis, gene set enrichment analysis, and principal component analysis were performed to evaluate the capability of the immune lncRNA signature as a prognostic indicator. Six long non-coding RNAs were identified via correlation analysis and Cox regression analysis considering their interactions with immune genes. Subsequently, tumor samples were categorized into two distinct risk groups based on different clinical outcomes. Stratification analysis indicated that the prognostic ability of this signature acted as an independent factor. The Kaplan-Meier method was employed to conduct survival analysis, results showed a significant difference between the two risk groups. The predictive performance of this signature was validated by principal component analysis (PCA). Additionally, data obtained from gene set enrichment analysis (GSEA) revealed several potential biological processes in which these biomarkers may be involved. To summarize, this study demonstrated that this six-lncRNA signature could be identified as a potential factor that can independently predict the prognosis of LIHC patients.