Abstract P3-20-03: Breast-conserving surgery improves the outcomes of disease-free survival and overall survival in young women with breast cancer (≤35 years): A retrospective study based on surgical options
Authors: Li Pei , Li Lun , Xue Jingyan , Wu Jiong 
Published: March 2022

Abstract
Background:Compared with non-young patients, young women with breast cancer (YWBC) has worse prognosis and higher risk of recurrence. Under the age of 35 is an independent risk factor of local recurrence in breast cancer patients, and the proportion of YWBC in China is higher than that in Western countries. Although surgery is the most important local treatment for YWBC, there still lack prospective studies to compare that three major surgical options for cancer recurrence and patient survival. So we retrospectively compared the outcomes of the three surgical options on disease-free survival(DFS) and overall survival(OS) of YWBC in Fudan University Shanghai Cancer Center(FUSCC).Method:YWBC (age ≤ 35) who underwent surgery in FUSCC from 2008 to 2016 were enrolled in analysis, and divided into three groups according to their surgical options:(1)breast-conserving surgery,(2)mastectomy alone, and (3)mastectomy with reconstruction. The survival outcome differences among the three groups were compared using Kaplan-Meier method and Cox regression model. Propensity score matching was also used to balance the baseline characteristics to eliminate selection bias.Results:A total of 1520 YWBC were enrolled with the median followed up for 5.1 years, including 524 patients (34.5%) who underwent breast-conserving surgery, 676 patients (44.5%) who underwent mastectomy alone, and 320 patients (21.1%) who underwent mastectomy with reconstruction; The 5-year DFS was 96%, 87%, and 93%, respectively; 10-year DFS was 93%, 82%, and 87%, respectively (P &lt; 0.001); The 5-year OS was 98%, 94%, and 97%, respectively; and 10-year OS was 97%, 87%, and 91%, respectively (P = 0.002). The multivariate Cox analysis showed that DFS and OS were significantly improved in patients undergoing breast-conserving surgery compared with those undergoing mastectomy alone, with HR of 0.448, [95% CI 0.276 ~ 0.728] P = 0.001; 0.405, [95% CI 0.206 ~ 0.797] P = 0.009, respectively. After propensity score matching, the DFS and OS were significantly improved in patients undergoing breast-conserving surgery compared with patients undergoing mastectomy alone (DFS P = 0.001, OS P = 0.009); the outcome of patients underwent mastectomy with reconstruction was also improved compared with patients underwent mastectomy alone in terms of DFS and OS, but the difference was not statistically significant (DFS P = 0.164, OS P = 0.130). Conclusion:Surgical options was an independent factor affecting DFS and OS in YWBC, and the DFS and OS were significantly improved in patients who underwent breast-conserving surgery compared with those who underwent mastectomy alone. The reason of this result may be related to the development of systemic therapy that reduce the local recurrence of breast-conserving surgery. Furthermore, complete body image could make those patients return to families and society, and ensure the quality of life. These findings still need further investigation. Taken together, breast conserving surgery are preferred for early YWBC, and mastectomy with reconstruction are the best option for remodeling the image of YWBC who can not receive breast conserving surgery.
Citation Format: Pei Li, Lun Li, Jingyan Xue, Jiong Wu. Breast-conserving surgery improves the outcomes of disease-free survival and overall survival in young women with breast cancer (≤35 years): A retrospective study based on surgical options [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-20-03.