Cheng-En Tsai1, Keng-Liang Wu2, Yi-Chun Chiu3, Seng-Kee Chuah3, Wei-Chen Tai1, Ming-Luen Hu1, Chih-Ming Liang1. 1. Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan. 2. Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan; Chang Gung University, College of Medicine, Kaohsiung, Taiwan; Graduate Institute of Clinical Medical Sciences, Chang Gung University, Kaohsiung, Taiwan. Electronic address: kengliang_wu@yahoo.com.tw. 3. Division of Hepatogastroenterology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, 833, Taiwan; Chang Gung University, College of Medicine, Kaohsiung, Taiwan.
Abstract
BACKGROUND/ PURPOSE: Interval colorectal cancer (CRC) is an emerging issue in CRC screening and surveillance. The frequency of interval CRC and its associated factors have not been well studied in Eastern Asia. We aim to clarify the factors associated with interval CRC. METHODS: CRC patients who had negative colonoscopy results 6-36 months prior to cancer diagnosis were defined as cases of interval CRC. Patient characteristics, past history, colon preparation, colonoscopy findings, and pathology were retrospectively evaluated. A total of 670 patients with colorectal adenocarcinoma by pathology who also underwent colonoscopy before diagnosis from January 2005 to November 2014 were recruited. RESULTS: Twenty-two (3.28%) patients (65.7 ± 9.2 years old; 9 male) were diagnosed with interval CRC. The interval CRCs were predominantly located at the rectum and cecum, and presented as earlier stage cancers (Stage I and Stage II: 86.4%, Stage III and Stage IV: 13.6%). Factors associated with interval cancer include end-stage renal disease (ESRD) (hazard ratio: 10.494, 95% confidence interval: 2.131-51.681) and shorter ascending colon withdrawal time (interval cancer: noninterval cancer 2.00±0.82: 4.91±3.74 minutes; hazard ratio: 0.561, 95% confidence interval: 0.345-0.913). Prior polypectomy and tumor size also tended to be related to interval CRC. CONCLUSION: The prevalence of interval CRC in the present study is 3.28%. Comorbidity with ESRD and shorter ascending colon withdrawal time could be factors associated with interval CRC. Good colon preparation for the patients with ESRD and more ascending colon withdrawal time could reduce the interval CRC.
BACKGROUND/ PURPOSE: Interval colorectal cancer (CRC) is an emerging issue in CRC screening and surveillance. The frequency of interval CRC and its associated factors have not been well studied in Eastern Asia. We aim to clarify the factors associated with interval CRC. METHODS: CRC patients who had negative colonoscopy results 6-36 months prior to cancer diagnosis were defined as cases of interval CRC. Patient characteristics, past history, colon preparation, colonoscopy findings, and pathology were retrospectively evaluated. A total of 670 patients with colorectal adenocarcinoma by pathology who also underwent colonoscopy before diagnosis from January 2005 to November 2014 were recruited. RESULTS: Twenty-two (3.28%) patients (65.7 ± 9.2 years old; 9 male) were diagnosed with interval CRC. The interval CRCs were predominantly located at the rectum and cecum, and presented as earlier stage cancers (Stage I and Stage II: 86.4%, Stage III and Stage IV: 13.6%). Factors associated with interval cancer include end-stage renal disease (ESRD) (hazard ratio: 10.494, 95% confidence interval: 2.131-51.681) and shorter ascending colon withdrawal time (interval cancer: noninterval cancer 2.00±0.82: 4.91±3.74 minutes; hazard ratio: 0.561, 95% confidence interval: 0.345-0.913). Prior polypectomy and tumor size also tended to be related to interval CRC. CONCLUSION: The prevalence of interval CRC in the present study is 3.28%. Comorbidity with ESRD and shorter ascending colon withdrawal time could be factors associated with interval CRC. Good colon preparation for the patients with ESRD and more ascending colon withdrawal time could reduce the interval CRC.