Evaluation of the impact of health screening on mortality: A study using the Japanese Cancer Registry Database

抄録

Background: Cancer is a leading cause of death worldwide, and early detection has been associated with improved survival. However, the association between cancer detection through health checkups and survival remains debated, particularly for hard-to-screen cancers such as pancreatic cancer.

Objective: To examine the association between cancer detection through health checkups and survival using population-based cancer registry data from Chiba Prefecture, Japan.

Methods: We conducted a cohort study using National Cancer Registry data of patients diagnosed in Chiba Prefecture between 2013 and 2020. Patients were classified into three mutually exclusive cancer groups: screening-targeted cancers, non-screening-targeted cancers, and pancreatic cancer. Cox proportional hazards models were used to assess the association between detection through health checkups and cancer-specific mortality.

Results: Among 254,370 cancer patients, detection through health checkups was associated with more favorable survival in screening-targeted cancers (hazard ratio [HR] 0.41, 95% confidence interval [CI]: 0.33–0.51) and non-screening-targeted cancers (HR 0.15, 95% CI: 0.10–0.22). In pancreatic cancer, health checkup detection was also associated with lower mortality (HR 0.40, 95% CI: 0.19–0.84), although estimates were less consistent in subgroup analyses. The association between health checkup detection and survival differed by sex in both screening-targeted and non-screening-targeted cancers.

Conclusion:

Cancer detection through health checkups was associated with more favorable survival among diagnosed patients, with heterogeneity by cancer type and sex. These findings should not be interpreted as evidence of causal mortality reduction but highlight important patterns in cancer detection and prognosis.