Comparative analysis of overall survival according to TNM shttps://s2rims.korea.ac.kr/kumedicine/conference/conferencePopup.do?conferenceId=5938&reload=true&userId=MEDLIB&timestamp=1734913731877#tage of IDC and ILC

초록

Background: Invasive lobular carcinoma (ILC) is the second most common cancer and has many differences compared to invasive ductal cancer (IDC) in epidemiology, clinicopathology, and natural history. ILC is characterized by hormone receptor-positive, human epidermal growth factor receptor 2 (HER 2) negative, and low to intermediate histologic grade, respectively. Diagnosing ILC is not easy. This may be why ILC has poor long-term outcomes compared to IDC. This study aims to investigate the clinicopathological characteristics of ILC and IDC in Korea and evaluate their impact on overall survival (OS) of each TNM stage of ILC and IDC. Material and Methods: The Korean Breast Cancer Society Registry was queried for breast cancer patients who underwent breast cancer surgery between January 2006 and December 2011. We selected 54,348 patients whose tumors were classified as IDC and ILC. Overall survival until December 2014 was analyzed according to TNM stage using Kaplan-Meier curves and Log-rank test. Clinicopathological factors at the time of initial operation, such as sex, age, menopausal status, estrogen and progesterone receptor (ER and PR) expression, HER2 status, Ki-67, surgical methods in breast and axilla and treatment trends, were compared between IDC and ILC. Results: Of 54,348 patients, there were 52,927 (97.4%) in IDC and 1,421 (2.6%) in ILC from 2006 to 2011. As of December 2014, the number of surviving patients was 49,038 (92.7%) for IDC and 1,328 (93.5%) for ILC. In univariate analysis, overall survival was influenced by age, ER and PR status, HER2 status, Ki67 and treatment trends regardless of histology, IDC and ILC (P < 0.001). Mortality rates were 7.3% in IDC and 6.5% in ILC. Overall survival did not differ between IDC and ILC (HR = 0.88, 95% CI = 0.74 to 1.09; P = 0.252). Additionally, overall survival according for TNM stage shows similar results in IDC and ILC (stage\xE2\x85; P = 0.946, stage II; P = 0.147, stage III; P = 0.486, stage IV; P = 0.272). When limiting the analyses to ER positive only, overall survival tended to be similar to before the restriction (HR = 0.88, 95% CI = 0.71 to 1.09; P = 0.137). Conclusion: When comparing IDC and ILC, there are no significant differences in overall survival in the same stage and estrogen receptor positive group.