Breast cancer is the second most frequent malignancy in Korean women, with a continuously increasing incidence. The Korean Breast Cancer Society has constructed a nationwide breast cancer database through an online registration program. The aim of the present study was to report the fundamental facts on Korean breast cancer in 2011, and to analyze the changing patterns in clinical characteristics and breast cancer management in Korea over the last 10 years. Data on newly diagnosed breast cancer patients, including the total number of cases, age, stage, and type of surgery, for the year 2011 were collected from 84 hospitals and clinics nationwide using a questionnaire survey. Additional data relating to the changing patterns of breast cancer in Korea were collected from the online breast cancer registry database and analyzed. According to nationwide survey data, a total of 16,967 patients were newly diagnosed with breast cancer in 2011. The crude incidence of female breast cancer, including invasive cancer and in situ cancer, was 67 cases per 100,000 women. Analysis of the survey and registry data gave equivalent results in terms of age distribution, stage, and type of surgery. The median age at diagnosis was 50 years, and the proportion of postmenopausal women (51.3%) was higher than that of premenopausal women (48.7%) with breast cancer. The incidence of stage 0 and stage I breast cancer increased continuously over the last 10 years (56.3% in 2011), and breast conserving surgery (65.7%) was performed more frequently than total mastectomy (33.8%). The total number of breast reconstruction surgeries increased approximately 8-fold. We conclude that the clinical characteristics of breast cancer have changed over the past 10 years in Korea, and surgical management has changed accordingly. Analysis of nationwide registry data will contribute to a better understanding of the characteristics of breast cancer in Korea.
Keywords: Breast neoplasms; Korea; Online systems; Registries.