Current cytology practices in Korea: A nationwide survey by the Korean society for cytopathology

Background: Limited data are available on the current status of cytology practices in Korea. This nationwide study presents Korean cytology statistics from 2015. Methods: A nationwide survey was conducted in 2016 as a part of the mandatory quality-control program by the Korean Society for Cytopathology. The questionnaire was sent to 208 medical institutions performing cytopathologic examinations in Korea. Individual institutions were asked to submit their annual cytology statistical reports and gynecologic cytology-histology correlation data for 2015. Results: Responses were obtained from 206 medical institutions including 83 university hospitals, 87 general hospitals, and 36 commercial laboratories. A total of 8,284,952 cytologic examinations were performed in 2015, primarily in commercial laboratories (74.9%). The most common cytology specimens were gynecologic samples (81.3%). Conventional smears and liquid-based cytology were performed in 6,190,526 (74.7%) and 2,094,426 (25.3%) cases, respectively. The overall diagnostic concordance rate between cytologic and histologic diagnoses of uterine cervical samples was 70.5%. Discordant cases were classified into three categories: category A (minimal clinical impact, 17.4%), category B (moderate clinical impact, 10.2%), and category C (major clinical impact, 1.9%). The ratio of atypical squamous cells of undetermined significance to squamous intraepithelial lesion was 1.6 in university hospitals, 2.9 in general hospitals, and 4.9 in commercial laboratories. Conclusions: This survey reveals the current status and trend of cytology practices in Korea. The results of this study can serve as basic data for the establishment of nationwide cytopathology policies and quality improvement guidelines in Korean medical institutions.