Application of the adjuvant! Online model to korean breast cancer patients: An assessment of prognostic accuracy and development of an alternative prognostic tool

Background: Adjuvant! Online (AOL) is a Web-accessible risk-assessment model that predicts the mortality and the benefits of adjuvant therapy for breast cancer. Methods: Using the Yonsei Tumor Registry database, patients with T1-3, N0-3, M0 breast cancer who were treated at the Yonsei Cancer Center between 1986 and 1999 were entered into AOL version 8.0 to calculate survival. Results: The median age of the study population was 45 years (range, 23-76 years) and the median follow-up duration was 10.8 years (range, 0.1-25.9 years) for all 699 patients. AOL significantly overestimated overall survival (OS) (by 11.1 %, P < 0.001), breast cancer-specific survival (BCSS) (by 11.6 %, P < 0.001), and event free-free survival (EFS) (by 9.25 %, P < 0.001) in Korean patients. Therefore, we developed a Korean version of AOL (KAOL), which is a new model for prognosis based on AOL's parameters. The observed 10-year OS (61.4 %), BCSS (62.3 %), and EFS (59.1 %) and the KAOL predicted OS (61.5 %), BCSS (63.5 %) and EFS (57.6 %) were not different (P = 0.976, P = 0.771, and P = 0.674, respectively). Conclusions: AOL was not found to be suitable in Korean patients with breast cancer. The newly developed KAOL accurately predicted 10-year outcomes in Korean breast cancer patients.