• 제목/요약/키워드: Kaplan-Meier analysis

검색결과 460건 처리시간 0.032초

HOXB7 Predicts Poor Clinical Outcome in Patients with Advanced Esophageal Squamous Cell Cancer

  • Long, Qing-Yun;Zhou, Jun;Zhang, Xiao-Long;Cao, Jiang-Hui
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권4호
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    • pp.1563-1566
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    • 2014
  • Background: Esophageal squamous cell carcinoma (ESCC) accounts for most esophageal cancer in Asia, and is the sixth common cause of cancer-related deaths worldwide. Previous studies indicated HOXB7 is overexpressed in ESCC tissues, but data on prognostic value are limited. Methods: A total of 76 advanced ESCC cases were investigated. Immunohistochemistry (IHC) was used to detect the expression levels of HOXB7 and Kaplan-Meier curves and Cox regression models to determine prognostic significance. Stratified analysis was also performed according to lymph node (LN) status. Results: Kaplan-Meier curve analysis indicated that HOXB7 positive patients had significantly shorter overall survival (OS) than HOXB7 negative patients. Multivariate analysis using the Cox proportional hazards model indicated only TNM stage and HOXB7 expression to be independent predictors of overall survival of advanced ESCC patients. HOXB7 indicated poor OS in both lymph node negative (LN-) and lymph node positive (LN+) patients. Conclusion: HOXB7 predicts poor prognosis of advanced ESCC patients and can be applied as an independent prognostic predictor.

경쟁적 위험하에서의 회귀분석 (Competing Risks Regression Analysis)

  • 백재욱
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제18권2호
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    • pp.130-142
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    • 2018
  • Purpose: The purpose of this study is to introduce regression method in the presence of competing risks and to show how you can use the method with hypothetical data. Methods: Survival analysis has been widely used in biostatistics division. But the same method has not been utilized in reliability division. Especially competing risks, where more than a couple of causes of failure occur and the occurrence of one event precludes the occurrence of the other events, are scattered in reliability field. But they are not utilized in the area of reliability or they are analysed in the wrong way. Specifically Kaplan-Meier method is used to calculate the probability of failure in the presence of competing risks, thereby overestimating the real probability of failure. Hence, cumulative incidence function is introduced. In addition, sample competing risks data are analysed using cumulative incidence function along with some graphs. Lastly we compare cumulative incidence functions with regression type analysis briefly. Results: We used cumulative incidence function to calculate the survival probability or failure probability in the presence of competing risks. We also drew some useful graphs depicting the failure trend over the lifetime. Conclusion: This research shows that Kaplan-Meier method is not appropriate for the evaluation of survival or failure over the course of lifetime in the presence of competing risks. Cumulative incidence function is shown to be useful in stead. Some graphs using the cumulative incidence functions are also shown to be informative.

Black Hispanic and Black Non-Hispanic Breast Cancer Survival Data Analysis with Half-normal Model Application

  • Khan, Hafiz Mohammad Rafiqullah;Saxena, Anshul;Vera, Veronica;Abdool-Ghany, Faheema;Gabbidon, Kemesha;Perea, Nancy;Stewart, Tiffanie Shauna-Jeanne;Ramamoorthy, Venkataraghavan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권21호
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    • pp.9453-9458
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    • 2014
  • Background: Breast cancer is the second leading cause of cancer death for women in the United States. Differences in survival of breast cancer have been noted among racial and ethnic groups, but the reasons for these disparities remain unclear. This study presents the characteristics and the survival curve of two racial and ethnic groups and evaluates the effects of race on survival times by measuring the lifetime data-based half-normal model. Materials and Methods: The distributions among racial and ethnic groups are compared using female breast cancer patients from nine states in the country all taken from the National Cancer Institute's Surveillance, Epidemiology, and End Results cancer registry. The main end points observed are: age at diagnosis, survival time in months, and marital status. The right skewed half-normal statistical probability model is used to show the differences in the survival times between black Hispanic (BH) and black non-Hispanic (BNH) female breast cancer patients. The Kaplan-Meier and Cox proportional hazard ratio are used to estimate and compare the relative risk of death in two minority groups, BH and BNH. Results: A probability random sample method was used to select representative samples from BNH and BH female breast cancer patients, who were diagnosed during the years of 1973-2009 in the United States. The sample contained 1,000 BNH and 298 BH female breast cancer patients. The median age at diagnosis was 57.75 years among BNH and 54.11 years among BH. The results of the half-normal model showed that the survival times formed positive skewed models with higher variability in BNH compared with BH. The Kaplan-Meir estimate was used to plot the survival curves for cancer patients; this test was positively skewed. The Kaplan-Meier and Cox proportional hazard ratio for survival analysis showed that BNH had a significantly longer survival time as compared to BH which is consistent with the results of the half-normal model. Conclusions: The findings with the proposed model strategy will assist in the healthcare field to measure future outcomes for BH and BNH, given their past history and conditions. These findings may provide an enhanced and improved outlook for the diagnosis and treatment of breast cancer patients in the United States.

One-year Survival Rate of Patients with Primary Malignant Central Nervous System Tumors after Surgery in Kazakhstan

  • Akshulakov, Serik;Igissinov, Nurbek;Aldiyarova, Nurgul;Akhmetzhanova, Zauresh;Ryskeldiyev, Nurzhan;Auezova, Raushan;Zhukov, Yevgeniy
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권16호
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    • pp.6973-6976
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    • 2014
  • This study was conducted to evaluate the one-year survival rate of patients with primary malignant central nervous system (CNS) tumors after surgical treatment in Kazakhstan. Retrospective data of patients undergoing operations in the Department of Central Nervous System Pathology in the JSC National Centre for Neurosurgery in the period from 2009 to 2011 were used as the research material. Kaplan-Meier survival analysis was performed with the following information: gender, date of birth, place of residence, diagnosis according to ICD-10, the date of the operation, the morphological type of tumor, clinical stage, state at the end of the first year of observation, and the date of death. The study was approved by the ethical committee of the JSC National Centre for Neurosurgery. The overall one-year overall survival rate (n=152) was 56.5% (95% confidence interval (CI): 50.2-62.7), and 79.5% (95% CI 72.2-86.8) and 33.1% (95% CI: 21.0-42.3) for Grades I-II (n=76) and Grades III-IV (n=76), respectively. Significant prognostic factors which affected the survival rate were age and higher tumor grade (Grades III-IV), corresponding with results described elsewhere in the world.

Tests based on EDF statistics for randomly censored normal distributions when parameters are unknown

  • Kim, Namhyun
    • Communications for Statistical Applications and Methods
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    • 제26권5호
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    • pp.431-443
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    • 2019
  • Goodness-of-fit techniques are an important topic in statistical analysis. Censored data occur frequently in survival experiments; therefore, many studies are conducted when data are censored. In this paper we mainly consider test statistics based on the empirical distribution function (EDF) to test normal distributions with unknown location and scale parameters when data are randomly censored. The most famous EDF test statistic is the Kolmogorov-Smirnov; in addition, the quadratic statistics such as the $Cram{\acute{e}}r-von$ Mises and the Anderson-Darling statistic are well known. The $Cram{\acute{e}}r-von$ Mises statistic is generalized to randomly censored cases by Koziol and Green (Biometrika, 63, 465-474, 1976). In this paper, we generalize the Anderson-Darling statistic to randomly censored data using the Kaplan-Meier estimator as it was done by Koziol and Green. A simulation study is conducted under a particular censorship model proposed by Koziol and Green. Through a simulation study, the generalized Anderson-Darling statistic shows the best power against almost all alternatives considered among the three EDF statistics we take into account.

비재무정보를 이용한 사회적기업의 생존에 영향을 미치는 요인에 관한 실증연구 (An Empirical Study on Factors Affecting the Survival of Social Enterprises Using Non-Financial Information)

  • 김혁;이동명;남기정
    • 산업융합연구
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    • 제21권1호
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    • pp.111-122
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    • 2023
  • 본 연구의 목적은 신용보증기관에서 신용보증을 이용한 사회적기업의 비재무정보를 사용하여 생존율과 생존시간을 추정하고 생존시간에 영향을 주는 요인들을 검증하여 이해관계자에게 정보를 제공하고 생존율을 향상시켜 기업의 고용을 유지·확대하여 사회·경제적 비용을 감소시키는데 기여하고자 한다. 연구방법은 비모수적 분석방법인 카플란마이어 분석법(Kaplan-Meier Analysis)으로 생존분석을 실시하였다. 연구대상 기업은 2009년부터 2018년 사이에 설립된 621개(정상기업 577개, 부실기업 44개) 기업을 표본으로 선정하였다. 사회적기업의 대표자정보와 기업정보로 구분하여 생존시간에 영향을 주는 요인들을 검증한 결과 대표자 신용등급, 대표자 주택보유여부, 여신거래기간, 기업 신용등급이 생존시간에 영향을 주는 유의미한 변수로 도출되었다. 향후 금융기관들은 사회적기업 대출심사시 생존에 영향을 미치는 요인들을 반영하여 기업의 건전성을 유인하고, 고용유지와 사회적비용 감소에 기여할 수 있을 것이다. 정부나 민간단체 등 지원기관들은 사회적기업의 성장과 지속가능성을 위한 정책수립, 교육훈련 등에도 다양하게 활용이 가능할 것이다. 본 연구를 계기로 사회적기업의 성과와 더불어 기업의 부실과 관련하여 영향을 미치는 요인들에 대하여 더욱 관심을 갖고 연구가 지속되길 바란다.

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
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    • 제34권4호
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    • pp.958-968
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    • 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.

Hepatocellular Carcinoma: Texture Analysis of Preoperative Computed Tomography Images Can Provide Markers of Tumor Grade and Disease-Free Survival

  • Jiseon Oh;Jeong Min Lee;Junghoan Park;Ijin Joo;Jeong Hee Yoon;Dong Ho Lee;Balaji Ganeshan;Joon Koo Han
    • Korean Journal of Radiology
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    • 제20권4호
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    • pp.569-579
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    • 2019
  • Objective: To investigate the usefulness of computed tomography (CT) texture analysis (CTTA) in estimating histologic tumor grade and in predicting disease-free survival (DFS) after surgical resection in patients with hepatocellular carcinoma (HCC). Materials and Methods: Eighty-one patients with a single HCC who had undergone quadriphasic liver CT followed by surgical resection were enrolled. Texture analysis of tumors on preoperative CT images was performed using commercially available software. The mean, mean of positive pixels (MPP), entropy, kurtosis, skewness, and standard deviation (SD) of the pixel distribution histogram were derived with and without filtration. The texture features were then compared between groups classified according to histologic grade. Kaplan-Meier and Cox proportional hazards analyses were performed to determine the relationship between texture features and DFS. Results: SD and MPP quantified from fine to coarse textures on arterial-phase CT images showed significant positive associations with the histologic grade of HCC (p < 0.05). Kaplan-Meier analysis identified most CT texture features across the different filters from fine to coarse texture scales as significant univariate markers of DFS. Cox proportional hazards analysis identified skewness on arterial-phase images (fine texture scale, spatial scaling factor [SSF] 2.0, p < 0.001; medium texture scale, SSF 3.0, p < 0.001), tumor size (p = 0.001), microscopic vascular invasion (p = 0.034), rim arterial enhancement (p = 0.024), and peritumoral parenchymal enhancement (p = 0.010) as independent predictors of DFS. Conclusion: CTTA was demonstrated to provide texture features significantly correlated with higher tumor grade as well as predictive markers of DFS after surgical resection of HCCs in addition to other valuable imaging and clinico-pathologic parameters.

폐 편평세포암종 내 Leucine-Rich Repeat Kinase 2 암촉진 효과와 Interleukin-10 발현과의 연관성 (Correlation of Protumor Effects of Leucine-Rich Repeat Kinase 2 with Interleukin-10 Expression in Lung Squamous Cell Carcinoma)

  • 이성원;박상욱
    • 대한임상검사과학회지
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    • 제55권2호
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    • pp.105-112
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    • 2023
  • Leucine-rich repeat kinase 2 (LRRK2)는 파킨슨병과 같은 신경퇴행성 질환의 병태생리학적인 측면에서 중요한 역할을 하는 것으로 알려져 있고 주로 뇌뿐만 아니라 폐에서도 발현된다. 그러나 LRRK2 발현이 폐 편평세포암(lung squamous cell carcinoma, LUSC)과 같은 일반적인 폐암의 아형과 병인성이 있는지는 불분명하다. 본 연구에서는 Kaplan Meier 플로터 생물정보학 온라인 도구를 사용하여 폐 편평세포암종 내에서 LRRK2와의 예후 진단가치를 분석하였다. 폐 편평세포암종 환자는 LRRK2의 발현이 높아지면 더 나쁜 예후를 나타낸다고 알려져 왔다. LRRK2 발현이 높은 환자의 경우 종양 돌연변이 부담, 높은 신항원부하, 더 나쁜 생존율, 성별과 상관관계를 보였다. 더욱이, gene expression profiling interactive analysis 데이터분석에서 높은 LRRK2 발현을 가진 환자에서의 심각한 증상은 항염증성 사이토카인(예, IL-4, IL-10)의 높은 발현에 양의 상관관계를 보였지만 염증성 사이토카인은 상관성이 없었다. 이러한 결과에서 IL-10관련 유전자의 높은 발현은 더 나쁜 예후를 보이는 LRRK2-high 환자들에서 유의미하게 연관성을 보였다. 또한, tumor immunity estimation resource 데이터는 큰포식세포가 LRRK2-high LUSC환자에서 IL-10의 기원세포 중 하나임을 보여주었다. 본 연구를 통해 결과적으로 LRRK2-IL10 축의 가설이 LUSC 환자의 잠재적이 치료 표적과 예후 바이오 마커일 수 있음을 보여주었다.

Conservative Neck Dissection in Oral Cancer Patients: a 5 Year Retrospective Study in Malaysia

  • Balasundram, Sathesh;Mustafa, Wan Mahadzir Wan;Ip, Jolene;Adnan, Tassha Hilda;Supramaniam, Premaa
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권8호
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    • pp.4045-4050
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    • 2012
  • Objective: The impact of ablative oral cancer surgery was studied, with particular reference to recurrence and nodal metastasis, to assess survival probability and prognostic indicators and to elucidate if ethnicity influences the survival of patients. Methods: Patients who underwent major ablative surgery of the head and neck region with neck dissection were identified and clinical records were assessed. Inclusion criteria were stage I-IV oral and oropharyngeal malignancies necessitating resection with or without radiotherapy from 2004 to 2009. All individuals had a pre-operative assessment prior to the surgery. The post operative assessment period ranged from 1 year to 5 years. Survival distributions were analyzed using Kaplan-Meier curves. Results: 87 patients (males:38%; females:62%) were included in this study, with an age range of 21-85 years. Some 78% underwent neck dissections while 63% had surgery and radiotherapy. Nodal recurrence was detected in 5.7% while 20.5% had primary site recurrence within the study period. Kaplan-Meier survival analysis revealed that the median survival time was 57 months. One year overall survival (OS) rate was 72.7% and three year overall survival rate dropped to 61.5%. On OS analysis, the log-rank test showed a significant difference of survival between Malay and Chinese patients (Bonferroni correction p=0.033). Recurrence-free survival (RFS) analysis revealed that 25% of the patients have reached the event of recurrence at 46 months. One year RFS rate was 85.2% and the three year survival rate was 76.1%. In the RFS analysis, the log-rank test showed a significant difference in the event of recurrence and nodal metastasis (p<0.001). Conclusion: Conservative neck is effective, in conjunction with postoperative radiotherapy, for control of neck metastases. Ethnicity appears to influence the survival of the patients, but a prospective trial is required to validate this.