Hyewon Bang¹, Tae Kyung Yoo², Oh Joon Kwon¹, Woo Chan Park² and Yong Hwa Eom¹*
1Department of Surgery, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
2Department of Surgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
Purpose: To evaluate whether the recently updated 8th edition of the American Joint Committee on Cancer (AJCC) staging systems represents better refinement of the 7th edition for breast cancer. Methods: Data of 3,140 patients who were newly diagnosed with malignant breast cancer between January 2005 and December 2015 at a single institute were retrospectively reviewed. Invasive breast cancer was restaged according to the 8th edition of the AJCC staging system distributed on December 15th 2017. Five-year recurrence and survival rates were compared between the 7th edition and the 8th edition. Results: According to the 7th edition and the 8th edition staging system, stage migration was observed in 947 (38.4%) patients. Of these, 214 (22.6%) patients showed upgraded stage while 733 (77.4%) patients showed downgraded stage with the 8th edition compared to those with the 7th edition. Using the 7th edition staging system, 5-year Recurrence Free Survival (RFS) rates for patients with stage IIB disease and stage IIIB were lower (p<0.001) than those of patients with stage IIIA and IIIC. Five-year Disease-Specific Survival (DSS) and Overall Survival (OS) rates for patients with stage IB disease were lower (p<0.001) than those of patients with stage IIA disease. Conclusion: The recently updated 8th edition of AJCC staging system provides finer stratification of breast cancer with more accurate information about prognosis than the 7th edition staging system.
Bang H, Yoo TK, Kwon OJ, Park WC, Eom YH. Retrospective Prognostic Evaluation Using the 8th Edition vs. the 7th Edition of AJCC Staging System for Breast Cancer: A Single Institution Study of 3,140 Patients in Korea. Clin Surg. 2021; 6: 3348..