Waiting Time for Breast Cancer Treatment in Korea: A Nationwide Cohort Study

PURPOSE: This study aimed to analyze the waiting time for initial treatment after breast cancer diagnosis and determine the factors influencing treatment delay in South Korea. METHODS: This nationwide retrospective cohort study was conducted using the Health Insurance Review and Assessment data. The participants were classified according to the regions where their biopsy and treatment were performed (Seoul-Seoul, Metro-Metro, Other-Other, Metro-Seoul, Other-Seoul). Waiting time was analyzed according to regional subgroup, year of diagnosis, and type of treatment. Multivariable logistic regression models were constructed to identify the factors associated with treatment delay (after 30 days of diagnosis). RESULTS: A total of 133,514 participants newly diagnosed between January 2010 and December 2017 were included in the study. The median waiting time for initial treatment in the total population increased from 8 days, in 2010, to 14 days, in 2017. In the Seoul-Seoul group, the waiting time increased from 10 days, in 2010, to 16 days, in 2017. Although the median waiting time was approximately 10 days in the Metro-Metro and Other-Other groups, it was 27 and 24 days, in the Metro-Seoul and Other-Seoul group, respectively, in 2017. The proportion of delayed upfront surgery by more than 30 days was higher in the Metro-Seoul (odds ratio [OR], 8.088; 95% confidence interval [CI], 7.357–8.893; p < 0.001) and Other-Seoul (OR, 6.210; 95% CI, 5.717–6.750; p < 0.001) groups than in the Metro-Metro (OR, 1.468; 95% CI, 1.352–1.594; p < 0.001) and Other-Other (reference) groups. Previous medical history and treatment at tertiary hospital were observed as factors related to delayed surgery. CONCLUSION: Waiting times for breast cancer surgery have increased across all regions of Korea, with those traveling to Seoul experiencing particularly long wait times.