Investigating Factors Influencing the National Cancer Screening Program among Older Individuals in Republic of Korea-Data from the Korea National Health and Nutrition Examination Survey VIII.

This study aims to determine the influencing factors of the participation of older individuals aged 65 years and above in South Korea's National Cancer Screening Program (NCSP) using data from the eighth wave (2019-2021) of the Korea National Health and Nutrition Examination Survey (KNHANES VIII), and discuss potential problems and coping strategies. Variables were selected based on Andersen's healthcare utilization model. "Participation in the NSCP" was considered the dependent variable, with independent variables including sociodemographic characteristics (sex, marital status, residence, education level, income level, economic activity, medical coverage type, and private insurance), health conditions (subjective health status, hypertension, and diabetes), and health behaviors (physical activity, monthly alcohol consumption, and current smoking status). The analysis revealed that higher participation rates correlated with being married, having an education level beyond elementary school, being employed, subscribing to private insurance, perceiving oneself as having average or poor health, engaging in physical activity, and not smoking. Sex, residence, income, medical coverage type, hypertension, diabetes, and monthly alcohol consumption were found to be insignificantly correlated. These findings underscore the importance of tailored promotion and health education for older individuals to boost NCSP participation rates, which could ultimately elevate public health standards.

Korean colonoscopy screening pilot study (K-cospi) for screening colorectal cancer: study protocol for the multicenter, community-based clinical trial.

BACKGROUND: The Korean National Cancer Screening Program has been providing annual fecal immunochemical test for colorectal cancer (CRC) to adults aged 50 years and older since 2004. The Korean Colonoscopy Screening Pilot Study was developed to evaluate the effectiveness of colonoscopy screening for CRC incidence and mortality, screening-related complications, and acceptability of colonoscopy as a primary modality for the national CRC screening program. METHODS: This study and its protocols have been approved by the Korean Public Institutional Review Board and the National Cancer Center Institutional Review Board. We obtain written informed consent from all participants. The target population is males and females aged 50-74 years living within the pilot sites. A total of 26,640 participants will be recruited for colonoscopy screening. Subjects who have been diagnosed with CRC, who are currently undergoing treatment for CRC, or who have undergone colonoscopy screening within the past 5 years are not allowed to participate. All participants need to complete baseline questionnaires. This pilot study is currently conducted by 104 endoscopists from 57 national cancer screening institutions (42 primary, 10 secondary, and 5 tertiary institutions) located in Goyang-si, Gimpo-si, and Paju-si. The number of endoscopists, medical institutions, and districts participating in the pilot study will be expanded, if necessary. Participating endoscopists at each medical institution perform colonoscopy and report the colonoscopy results to a centralized electronic case report system. We conduct a telephone survey after 7 days and 4 weeks post-colonoscopy to assess for procedure-related complications and satisfaction of the participants. In case of abnormal findings from colonoscopy screening, we track the results from follow-up diagnostic tests. Data from this pilot study will be linked to the diagnostic workup results, the Korean Cancer Registry, and death certificate data for analysis of the performance, long-term effects, and cost-effectiveness of colonoscopy. DISCUSSION: The results will provide critical information to determine whether the introduction of colonoscopy as the primary modality of the Korean National Cancer Screening Program would be acceptable and feasible. Trial registration Korean Clinical Research Information Service registry, KCT0004142. Registered on 15 July 2019, http://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=16227.

Association of Regular Endoscopic Screening with Interval Gastric Cancer Incidence in the National Cancer Screening Program.

Although regular endoscopic screening may help in early detection of gastric cancer, interval cancer remains a problem in the screening program. This study evaluated the association between regular endoscopic screening and interval cancer detection in the Korean National Cancer Screening Program (KNCSP). We defined three groups (regularly, irregularly, and not screened) according to the screening interval, and the trends in the interval cancer rate (ICR) between the groups were tested using the Cochran-Armitage test. The influence of regular endoscopic screening on the risk of interval cancer was evaluated using multivariable logistic regression. Among the 11,642,410 participants who underwent endoscopy, the overall ICR was 0.36 per 1000 negative screenings. The ICR of the not screened group (0.41) was the highest among the three groups and the risk of interval cancer in this group was 1.68 times higher (p < 0.001) than that in the regularly screened group. Women in their 40s who had regular screening with no history of intestinal metaplasia and gastric polyps would have the lowest probability of having interval cancer (0.005%). Regular participation in endoscopic screening programs for reducing the risk of interval cancer may help to improve the quality of screening programs.

A Survey of Liver Cancer Specialists' Views on the National Liver Cancer Screening Program in Korea.

Background/Aims: To reduce the cancer burden, the Korean government initiated the National Cancer Control Plan including the National Liver Cancer Screening Program (NLCSP). Ultrasonography examinations and α-fetoprotein tests at six-month intervals are currently offered for high-risk individuals. High-risk individuals are identified by reviewing the National Health Insurance Service claims data for medical use for the past two years using International Classification of Diseases Codes for specific liver disease. We surveyed the attitudes and opinions towards the NLCSP to understand the issues surrounding the NLCSP in Korea. Methods: Altogether, 90 Korean Liver Cancer Association members participated in online and offline surveys between November and December 2019. Results: Approximately one-quarter (27%) of the survey participants rated the NLCSP as very contributing and about two-thirds (68%) as contributing to some extent toward reducing hepatocellular carcinoma (HCC)-related deaths in Korea. Most (87.8%) responded that the current process of identifying high-risk individuals needs improvement. Many (78.9%) were concerned that the current process identifies individuals who use medical services and paradoxically misses those who do not. When asked for the foremost priority for improvement, solving 'duplication issues between the NLCSP and private clinic HCC screening practices' was the most commonly selected choice (23.3%). Conclusions: The survey participants positively rated the role of the NLCSP in reducing liver cancer deaths. However, many participants rated the NCLSP as needing improvement in all areas. This survey can be a relevant resource for future health policy decisions regarding the NLCSP in Korea.

[French national cancer screening programs: What does the future hold?] / Quelle évolution pour les programmes de dépistage des cancers ?

French national cancer screening programs : what does the future hold? Three organized screening programs are in place or being rolled out in France for breast, colorectal and cervical cancers. Short or medium-term developments aim at facilitating the integration of technological or organizational innovations and at meeting the quality and safety requirements of the screening procedure. However, the stakes differ between the different programs. It is for the screening of breast cancer, the oldest program, the integration of technological innovations, such as breast tomosynthesis -3D- and dematerialization of mammograms, and the renovation of the program in order to propose a personalized follow-up, better coordinated and with an increased involvement of general practitioners. For colorectal cancer, given that a highly effective screening program using a fecal immunological test has been rolled out in 2015, the challenge is now to increase participation, which is too low -35%-, in order to improve the impact of the program. The cervical cancer screening program, whose opportunistic practice is already widespread, is currently being deployed ; it aims to reduce inequalities in access to screening by sending invitations to women who have not been tested in the last 3 years; the sampling will be performed in liquid phase which allows to anticipate a future migration to the HPV test.

Quelle évolution pour les programmes de dépistage des cancers ? Trois programmes de dépistage organisé sont en place ou en cours de déploiement en France pour les cancers du sein, colorectal et du col de l'utérus. Les perspectives d'évolution à court ou moyen termes visent à faciliter l'intégration des innovations technologiques ou organisationnelles dans ces programmes et à satisfaire aux exigences de qualité et de sécurité de la procédure de dépistage. Les enjeux diffèrent cependant entre les différents programmes. Il s'agit pour le dépistage des cancers du sein, le programme le plus ancien, de l'intégration d'innovations technologiques, notamment la tomosynthèse et la dématérialisation des mammographies pour la seconde lecture, et de la rénovation du programme de sorte à proposer aux femmes un suivi personnalisé, mieux coordonné et impliquant davantage le médecin traitant. Pour le cancer colorectal, dans la mesure où un programme performant de dépistage par test immunologique est en place, l'enjeu est d'augmenter la participation, par trop insuffisante, ce qui permettra d'améliorer l'impact du programme. Le programme de dépistage du cancer du col de l'utérus, dont la pratique est déjà bien répandue, est quant à lui en phase de déploiement ; il vise à réduire les inégalités d'accès par l'envoi d'invitations en direction des femmes n'ayant pas réalisé de dépistage dans les 3 dernières années ; le prélèvement sera réalisé en phase liquide ce qui permet d'anticiper un passage au test HPV le cas échéant.

Breast Cancer Screening Program in Morocco: Status of implementation, organization and performance.

Breast Cancer Screening Program was introduced and rolled out in Morocco in 2010. Women between 40 and 69 years are screened at the primary health centers (PHC) with clinical breast examination (CBE). A comprehensive evaluation of the program was conducted in 2016-2017 for quality assurance and mid-term course correction. The evaluation process involved: in-depth interviews of program managers; focus group discussions with service-providers of screening, diagnosis and treatment; supportive supervisory visits to randomly selected PHCs and diagnostic centers; desk review of the national guidelines and other published documents; and analysis of the performance data compiled by the program-in-charge. We found that the program has strong political support, a well-organized management structure and documented national policy and protocol. In absence of a mechanism to identify and invite the eligible women individually, the program is opportunistic in nature. Every PHC is provided with an annual target to be screened. A highly visible annual campaign to educate and motivate women has a major impact on participation. Record keeping and data collection are paper-based. In the years 2015 and 2016, 1.1 and 1.5 million women were screened, respectively. In the year 2015, 62.8% of the annual target population was covered, CBE positivity was 3.2%, a further assessment rate of screen-positive women was 34.1% and the breast cancer detection rate was 1.0/1000 women. Systematic paper-based data collection enabled the assessment of some of the process and outcome indicators. The screening coverage was moderate and the cancer detection rate was low.

Difference of stage at cancer diagnosis by socioeconomic status for four target cancers of the National Cancer Screening Program in Korea: Results from the Gwangju and Jeonnam cancer registries.

BACKGROUND: The aim of this study was to evaluate whether stage at cancer diagnosis differed according to patient economic status. METHODS: A total of 10,528 patients with cancer of the stomach, colorectum, breast, or cervix, which are target organs of the Korean National Cancer Screening Program (NCSP; fully implemented in 2005) were extracted from population-based cancer registries. The patients were classified into four groups based on socioeconomic status (SES), as determined using their National Health Insurance (NHI) monthly premium at the time of cancer diagnosis. Cancer stage at diagnosis was defined as early (in situ/local) or late stage (regional/distant) based on the Surveillance, Epidemiology, and End Results (SEER) summary stage. Multivariable logistic regression analysis was performed to estimate the risk of non-local stage using age, residential area, and community deprivation index as covariates. RESULTS: The lowest SES subjects showed significantly higher risks of being diagnosed at a later stage for stomach, colorectal, and female breast cancer, but not for cervical cancer, compared with the highest SES subjects. The estimated ORs were 1.28 (95% CI, 1.10-1.49), 1.29 (95% CI, 1.03-1.61), and 1.35 (95% CI, 1.02-1.81) in the lowest SES subjects with stomach, colorectal, and breast cancer, respectively. CONCLUSIONS: In conclusion, later stage diagnoses of stomach, colon, and female breast cancer are still associated with SES in Korea in the era of the NCSP for the lower SES population.

Regional Variation in National Gastric Cancer Screening Rate in Korea / 보건행정학회지

BACKGROUND: This study purposed to analyze regional factors related to gastric cancer screening rate provided by national cancer screening program in Korea. METHODS: The unit of analysis was administrative districts of si∙gun∙gu level. Dependent variable was regional gastric cancer screening rate provided by national cancer screening program, and regional variables were selected to represent the regional characteristics such as demographic, health behavior and status, socioeconomic, and health resource. Tobit regression was applied for the analysis. RESULTS: Analysis results showed that gastric cancer screening rate was varied depending on regions from 47.8% to 69.1%. Tobit regression showed that gastric cancer screening rate had negative relationships with smoking rate, financial independence rate, and National Health Insurance premium per capita. And regional gastric cancer screening rate had positive relationships with sex ratio and number of gastric cancer screening center. CONCLUSION: Regional characteristics should be considered in establishing regional policies for increasing the gastric cancer screening rate.

Gender Differences in Elders' Participation in the National Cancer Screening Program: Evidence from the Korean National Health and Nutrition Examination Survey 2010-12.

BACKGROUND: Cancer-screening programs are effective in reducing cancer prevalence and mortality; however, cancer remains the leading cause of death in elderly people in Korea. The aim of this study was to identify the factors associated with elders' participation in the National Cancer Screening Program (NCSP) and differences in screening rates by gender. METHODS: Original data from the Korea National Health and Nutrition and Examination Survey were analyzed by logistic regression analysis. The sample consisted of 5,505 elderly individuals over age 60. Selected demographic variables, cancer screening participation, physical and psychological health status, and lifestyle were examined. RESULTS: The NCSP participation rates decreased in both men and women as age increased. Private medical insurance (OR 95% CI: 1.04-1.78), one or more chronic disease (OR 95% CI: 1.07-1.71), and current smoker (OR 95% CI: 0.52-0.94) had the strongest associations with cancer screening participation among men after multivariate adjustment. In contrast, cancer screening participation among women was significantly associated only with living place (OR 95% CI: 1.06-2.203) after multivariate adjustment. CONCLUSIONS: Effective health promoting interventions for elders require individualized programs that address gender-related factors associated with elders' participation in cancer screening programs.

Effectiveness of gastric cancer screening programs in South Korea: organized vs opportunistic models.

AIM: To investigate the outcome and effectiveness of two screening programs, National Cancer Screening Program (NCSP) and opportunistic screening (OS), for the detection of gastric cancer. METHODS: A total of 45  654 subjects underwent upper endoscopy as part of the NCSP or OS at the Chung-Ang University Healthcare System in Korea between January 2007 and December 2010. The study population was comprised of subjects over the age of 40 years. More specifically, subjects who took part in the NCSP were Medicaid recipients and beneficiaries of the National Health Insurance Corporation. Still photographs from the endoscopies diagnosed as gastric cancer were reviewed by two experienced endoscopists. RESULTS: The mean age of the screened subjects was 55 years for men and 54 years for women. A total of 126 cases (0.28%) of gastric cancer were detected from both screening programs; 100 cases (0.3%) from NCSP and in 26 cases (0.2%) from OS. The proportion of early gastric cancer (EGC) detected in NCSP was higher than that in OS (74.0% vs 53.8%, P = 0.046). Among the 34  416 screenees in NCSP, 6585 (19.1%) underwent upper endoscopy every other year as scheduled. Among the 11  238 screenees in OS, 3050 (27.1%) underwent upper endoscopy at least once every two years during the study period. The detection rate of gastric cancer was found to be significantly higher during irregular follow-up than during regular follow-up in both screening programs (0.3% vs 0.2%, P = 0.036). A higher incidence of EGC than advanced gastric cancer was observed during regular follow-up compared with irregular follow-up. CONCLUSION: Compliance to the screening program is more important than the type of screening system used.

Outcomes and Efficiency of National Gastric Cancer Screening Program in Korea

BACKGROUND/AIMS: The National Cancer Screening Program (NCSP) for Medicaid recipients has contributed to reduction of cancer-related mortality in Korea. Although biennial gastric cancer screening by endoscopy has been increasing in Korea as part of the NCSP, few studies have evaluated its efficiency. Therefore, we analyzed the outcomes and efficiency of the NCSP for gastric cancer using endoscopy in Korea. MATERIALS AND METHODS: We reviewed results from the NCSP for gastric cancer at Chung-Ang University Yong-San Hospital in Korea from March 2003 to March 2008. The study population comprised of Medicaid recipients more than 40 years old, who were taken from the National Health Insurance Corporation. RESULTS: A total of 7,278 asymptomatic subjects underwent endoscopy for gastric cancer screening. The mean age of the screened subjects was 51.3 years for men and 48.9 years for women. The male to female ratio of the screened subjects was 1.2:1. Gastric cancer was diagnosed in 32 (0.44%) of 7,278 subjects (22 men and 10 women). Their mean age was 54.4 years. Of these, 21 subjects (0.29%) were diagnosed as early gastric cancer (EGC) and 11 subjects (0.15%) were diagnosed as advanced gastric cancer. The proportion of EGCs among total gastric cancers was 65.6%. CONCLUSIONS: Despite accomplishments of the NCSP for gastric cancer in Korea, its effectiveness remains an issue. Efficiency and cost-effectiveness analysis will be needed for successful progression.

Prevalence and risk factor of erosive esophagitis observed in Korean National Cancer Screening Program.

Prevalence of erosive esophagitis (EE) has been increasing in Korea. The purpose of this study was to estimate prevalence of EE among low socioeconomic population in Korea and to investigate risk factors for EE. We reviewed the medical records of 7,278 subjects who were examined by upper endoscopy in the Korean National Cancer Screening Program at Chung-Ang University Yong-san Hospital from March 2003 to March 2008. The study population included subjects ≥ 40 yr of age who were Medicaid recipients and beneficiaries in the National Health Insurance Corporation. Multivariate analysis was used to determine risk factors for EE. Prevalence of EE was 6.7% (486/7,278). According to the LA classification system, LA-A in 344 subjects, LA-B in 135 subjects, and LA-C and D in 7 subjects. In multivariate analysis, age ≥ 60 yr, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and endoscopic hiatal hernia were significant risk factors for EE. The prevalence of EE in low socioeconomic Korean population is similar to that in personal annual medical check-ups. Risk factors for EE among them include old age, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and hiatal hernia.

Evidence-based National Cancer Screening program of Korea

Cancer is the leading cause of death in Korea. Therefore cancer control is one of the most important health issues. Cancer screening is the most promising strategy for controlling cancer. The National Cancer Screening Program started in 2002 in Korea. The goal of the program is to reduce the mortality or incidence rate of the cancer or both. To be effective, the evidence-based National Cancer Screening program should be implemented. For the evidence-based program, related indices were recommended for each step. When adopting a new cancer screening program, the predicted benefit and harm should be analysed, and when a decision is made to adopt the program, a pilot study for feasibility should be implemented. After implementing the community-based screening program, several types of the evaluation for the effectiveness of the program ought to be performed. The indices for each step were listed and discussed. And several conditions suggested for performing evidence-based national cancer screening program in Korea were discussed. Randomized clinical trials to compare the efficacy between the screening tools are recommended. And the study to evaluate the harm from the screening programs should be performed. To achieve the goal of the National Cancer Screening Program, evidence-based national cancer screening program should be performed.

Prevalence and Risk Factor of Erosive Esophagitis Observed in Korean National Cancer Screening Program

Prevalence of erosive esophagitis (EE) has been increasing in Korea. The purpose of this study was to estimate prevalence of EE among low socioeconomic population in Korea and to investigate risk factors for EE. We reviewed the medical records of 7,278 subjects who were examined by upper endoscopy in the Korean National Cancer Screening Program at Chung-Ang University Yong-san Hospital from March 2003 to March 2008. The study population included subjects > or = 40 yr of age who were Medicaid recipients and beneficiaries in the National Health Insurance Corporation. Multivariate analysis was used to determine risk factors for EE. Prevalence of EE was 6.7% (486/7,278). According to the LA classification system, LA-A in 344 subjects, LA-B in 135 subjects, and LA-C and D in 7 subjects. In multivariate analysis, age > or = 60 yr, male sex, BMI > or = 25, current smoking, alcohol consumption, fasting glucose level > or = 126 mg/dL, and endoscopic hiatal hernia were significant risk factors for EE. The prevalence of EE in low socioeconomic Korean population is similar to that in personal annual medical check-ups. Risk factors for EE among them include old age, male sex, BMI > or = 25, current smoking, alcohol consumption, fasting glucose level > or = 126 mg/dL, and hiatal hernia.

Clinical features of colorectal cancer detected by the national cancer screening program.

PURPOSE: Since 2004, the National Cancer Screening Program of Korea has included colorectal cancer screening based on primary screening with the fecal occult blood test (FOBT). We report on the clinical features of colorectal cancer detected by the National Cancer Screening Program. METHODS: We retrospectively analyzed 577 patients who underwent elective surgery for colorectal cancer at the Seoul National University Hospital between January 2008 and December 2009. We compared the clinical features of colorectal cancers detected by the National Cancer Screening Program (NCSP group) with those of the control group in terms of age, gender, preoperative symptom, location of the tumor, surgical technique and tumor-node-metastasis (TNM) stage. RESULTS: Age, gender, location of the tumor and operation types were not different between the two groups. The proportion of asymptomatic patients was significantly higher in the NCSP group than it was in the control group (86.5% vs. 20.0%; P < 0.001). The proportion of less invasive lesions (T1 or T2) was significantly higher in the NCSP group (46.3% vs. 27.7%; P = 0.002). The pathologic stages of the colorectal cancers in the NCSP group were I, 40.3%; II, 17.9%; III, 40.3% and IV, 1.5% whereas in the control group, they were I, 20.8%; II, 32.9%; III, 34.9% and IV, 11.4%. The proportion of stage I cancer was significantly higher in the NCSP group than in the control group (40.3% vs. 20.8%; P = 0.006). CONCLUSION: Our study demonstrates the FOBT in the NCSP is effective in early detection of colorectal cancer.

Trends of mammography use in a national breast cancer screening program, 2004-2008.

PURPOSE: Korea started breast cancer screening as part of the National Cancer Screening Program (NCSP) in 1999. In order to identify under-served groups, we investigated mammography uptake in the National Breast Cancer Screening Program. MATERIALS AND METHODS: The study population was participants in the National Breast Cancer Screening Program from 2004 to 2008. We analyzed participation rates by insurance type, age group, and area of residence. RESULTS: Total participation rates for breast cancer screening increased from 18.2% in 2004 to 35.0% in 2008. The participation rate in the group aged 60 to 69 years showed the greatest increase, 21.3%, among the four age groups. Although the screening rate increased continuously, the participation rate of the Medical Aid Program (MAP) group was low compared to the National Health Insurance (NHI) group. Moreover, the increasing trend of mammography uptake in the MAP group was much lower than that of the NHI group. CONCLUSION: The participation rate for breast cancer screening in the NCSP in Korea has increased. However, the participation rate in mammography among MAP recipients is still lower than that of NHI beneficiaries. To increase mammography uptake, it is important to make it available to everyone by ensuring inclusion of all population subgroups.

Trends of Mammography Use in a National Breast Cancer Screening Program, 2004-2008 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Korea started breast cancer screening as part of the National Cancer Screening Program (NCSP) in 1999. In order to identify under-served groups, we investigated mammography uptake in the National Breast Cancer Screening Program. MATERIALS AND METHODS: The study population was participants in the National Breast Cancer Screening Program from 2004 to 2008. We analyzed participation rates by insurance type, age group, and area of residence. RESULTS: Total participation rates for breast cancer screening increased from 18.2% in 2004 to 35.0% in 2008. The participation rate in the group aged 60 to 69 years showed the greatest increase, 21.3%, among the four age groups. Although the screening rate increased continuously, the participation rate of the Medical Aid Program (MAP) group was low compared to the National Health Insurance (NHI) group. Moreover, the increasing trend of mammography uptake in the MAP group was much lower than that of the NHI group. CONCLUSION: The participation rate for breast cancer screening in the NCSP in Korea has increased. However, the participation rate in mammography among MAP recipients is still lower than that of NHI beneficiaries. To increase mammography uptake, it is important to make it available to everyone by ensuring inclusion of all population subgroups.

Factors Associated with Cancer Screening Intention in Eligible Persons for National Cancer Screening Program / 예방의학회지

OBJECTIVES: To identify factors associated with cancer screening intention using the Theory of Planned Behavior (TPB). METHODS: Among 55,920 eligible persons for National Cancer Screening Program (NCSP) in J city, 1,100 individuals were contacted. Of these, 797 were interviewed using a structured questionnaire. Thirty-six responses were excluded due to incomplete data. The remaining 761 completed questionnaires were analyzed to find factors associated with cancer screening intention. RESULTS: Cancer screening intention was significantly associated with behavioral attitude (p<0.01) and subjective norm (p<0.01), but not with perceived behavioral control (p=0.29) in the TPB model. These three constructs explained 29.7% of cancer screening intention in multiple linear regression analysis. External factors such as socio-demographic status, health and health behavior variables explained 8.9% of screening intention. Among them, household monthly income, past cancer screening experience, exercise and daily eating habit were significantly associated with screening intention. CONCLUSIONS: Cancer screening intention may be influenced by focusing attitude, subjective norm in TPB model and other external factors. However, further studies are warranted to identify factors influencing cancer screening intention and behavior.

Clinical Features of Colorectal Cancer Detected by the National Cancer Screening Program

PURPOSE: Since 2004, the National Cancer Screening Program of Korea has included colorectal cancer screening based on primary screening with the fecal occult blood test (FOBT). We report on the clinical features of colorectal cancer detected by the National Cancer Screening Program. METHODS: We retrospectively analyzed 577 patients who underwent elective surgery for colorectal cancer at the Seoul National University Hospital between January 2008 and December 2009. We compared the clinical features of colorectal cancers detected by the National Cancer Screening Program (NCSP group) with those of the control group in terms of age, gender, preoperative symptom, location of the tumor, surgical technique and tumor-node-metastasis (TNM) stage. RESULTS: Age, gender, location of the tumor and operation types were not different between the two groups. The proportion of asymptomatic patients was significantly higher in the NCSP group than it was in the control group (86.5% vs. 20.0%; P < 0.001). The proportion of less invasive lesions (T1 or T2) was significantly higher in the NCSP group (46.3% vs. 27.7%; P = 0.002). The pathologic stages of the colorectal cancers in the NCSP group were I, 40.3%; II, 17.9%; III, 40.3% and IV, 1.5% whereas in the control group, they were I, 20.8%; II, 32.9%; III, 34.9% and IV, 11.4%. The proportion of stage I cancer was significantly higher in the NCSP group than in the control group (40.3% vs. 20.8%; P = 0.006). CONCLUSION: Our study demonstrates the FOBT in the NCSP is effective in early detection of colorectal cancer.