Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran
OBJECTIVES Colorectal cancer (CRC) patients are considered to have been cured when the mortality rate of individuals with the disease returns to the same level as expected in the general population. This study aimed to assess the impact of various risk factors on the cure fraction of CRC patients us...
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| Format: | Article |
| Language: | English |
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Korean Society of Epidemiology
2018-09-01
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| Series: | Epidemiology and Health |
| Subjects: | |
| Online Access: | http://www.e-epih.org/upload/pdf/epih-40-e2018045.pdf |
| _version_ | 1818109721418137600 |
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| author | Mehdi Azizmohammad Looha Mohamad Amin Pourhoseingholi Maryam Nasserinejad Hadis Najafimehr Mohammad Reza Zali |
| author_facet | Mehdi Azizmohammad Looha Mohamad Amin Pourhoseingholi Maryam Nasserinejad Hadis Najafimehr Mohammad Reza Zali |
| author_sort | Mehdi Azizmohammad Looha |
| collection | DOAJ |
| description | OBJECTIVES Colorectal cancer (CRC) patients are considered to have been cured when the mortality rate of individuals with the disease returns to the same level as expected in the general population. This study aimed to assess the impact of various risk factors on the cure fraction of CRC patients using a real dataset of Iranian CRC patients with a non-mixture non-parametric cure model. METHODS This study was conducted on the medical records of 512 patients who were definitively diagnosed with CRC at Taleghani Hospital, Tehran, Iran from 2001 to 2007. A non-mixture non-parametric cure rate model was applied to the data after using stepwise selection to identify the risk factors of CRC. RESULTS For non-cured cases, the mean survival time was 1,243.83 days (95% confidence interval [CI], 1,174.65 to 1,313.00) and the median survival time was 1,493.00 days (95% CI, 1,398.67 to 1,587.33). The 1- and 3-year survival rates were 92.9% (95% CI, 91.0 to 95.0) and 73.4% (95% CI, 68.0 to 79.0), respectively. Pathologic stage T1 of the primary tumor (estimate=0.58; p=0.013), a poorly differentiated tumor (estimate=1.17; p<0.001), a body mass index (BMI) between 18.6 and 24.9 kg/m2 (estimate=−0.60; p=0.04), and a BMI between 25.0 and 29.9 kg/m2 (estimate=−1.43; p<0.001) had significant impacts on the cure fraction of CRC in the multivariate analysis. The proportion of cured patients was 64.1% (95% CI, 56.7 to 72.4). CONCLUSIONS This study found that the pathologic stage of the primary tumor, tumor grade, and BMI were potential risk factors that had an impact on the cure fraction. A non-mixture non-parametric cure rate model provides a flexible framework for accurately determining the impact of risk factors on the long-term survival of patients with CRC. |
| first_indexed | 2024-12-11T02:35:45Z |
| format | Article |
| id | doaj.art-79b8fccf8121454086fee4aa104fe731 |
| institution | Directory Open Access Journal |
| issn | 2092-7193 |
| language | English |
| last_indexed | 2024-12-11T02:35:45Z |
| publishDate | 2018-09-01 |
| publisher | Korean Society of Epidemiology |
| record_format | Article |
| series | Epidemiology and Health |
| spelling | doaj.art-79b8fccf8121454086fee4aa104fe7312022-12-22T01:23:43ZengKorean Society of EpidemiologyEpidemiology and Health2092-71932018-09-014010.4178/epih.e2018045998Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in IranMehdi Azizmohammad Looha0Mohamad Amin Pourhoseingholi1Maryam Nasserinejad2Hadis Najafimehr3Mohammad Reza Zali4 Department of Biostatistics, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Science, Tehran, Iran Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, IranOBJECTIVES Colorectal cancer (CRC) patients are considered to have been cured when the mortality rate of individuals with the disease returns to the same level as expected in the general population. This study aimed to assess the impact of various risk factors on the cure fraction of CRC patients using a real dataset of Iranian CRC patients with a non-mixture non-parametric cure model. METHODS This study was conducted on the medical records of 512 patients who were definitively diagnosed with CRC at Taleghani Hospital, Tehran, Iran from 2001 to 2007. A non-mixture non-parametric cure rate model was applied to the data after using stepwise selection to identify the risk factors of CRC. RESULTS For non-cured cases, the mean survival time was 1,243.83 days (95% confidence interval [CI], 1,174.65 to 1,313.00) and the median survival time was 1,493.00 days (95% CI, 1,398.67 to 1,587.33). The 1- and 3-year survival rates were 92.9% (95% CI, 91.0 to 95.0) and 73.4% (95% CI, 68.0 to 79.0), respectively. Pathologic stage T1 of the primary tumor (estimate=0.58; p=0.013), a poorly differentiated tumor (estimate=1.17; p<0.001), a body mass index (BMI) between 18.6 and 24.9 kg/m2 (estimate=−0.60; p=0.04), and a BMI between 25.0 and 29.9 kg/m2 (estimate=−1.43; p<0.001) had significant impacts on the cure fraction of CRC in the multivariate analysis. The proportion of cured patients was 64.1% (95% CI, 56.7 to 72.4). CONCLUSIONS This study found that the pathologic stage of the primary tumor, tumor grade, and BMI were potential risk factors that had an impact on the cure fraction. A non-mixture non-parametric cure rate model provides a flexible framework for accurately determining the impact of risk factors on the long-term survival of patients with CRC.http://www.e-epih.org/upload/pdf/epih-40-e2018045.pdfColorectal cancerSurvival analysisNon-mixture cure rate modelsBody mass indexIran |
| spellingShingle | Mehdi Azizmohammad Looha Mohamad Amin Pourhoseingholi Maryam Nasserinejad Hadis Najafimehr Mohammad Reza Zali Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran Epidemiology and Health Colorectal cancer Survival analysis Non-mixture cure rate models Body mass index Iran |
| title | Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran |
| title_full | Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran |
| title_fullStr | Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran |
| title_full_unstemmed | Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran |
| title_short | Application of a non-parametric non-mixture cure rate model for analyzing the survival of patients with colorectal cancer in Iran |
| title_sort | application of a non parametric non mixture cure rate model for analyzing the survival of patients with colorectal cancer in iran |
| topic | Colorectal cancer Survival analysis Non-mixture cure rate models Body mass index Iran |
| url | http://www.e-epih.org/upload/pdf/epih-40-e2018045.pdf |
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