Overall breast cancer survival and prognostic factors.

Abstract

e12525 Background: Breast cancer is a frequent and heterogeneous disease where several clinical, histological and molecular factors determine its prognosis. Our objective is to estimate the prognostic factors influencing overall survival (OS) in patients with breast cancer. Methods: We conducted our first descriptive and analytical single-center study with a retrospective collection of data on files from the Medical Oncology department in University Hospital Center Tlemcen, including patients who died in 2020-2021 and were treated for breast cancer in order to estimate overall survival and determine prognostic factors. The study of survival was carried out by the Kaplan Meier method, and the comparison between the different classes of a variable was carried out by the log rank test. The study of prognostic factors associated with survival was carried out using the Cox model. Results: One hundred twenty-four patients were included. The average age was 50 years [30-87]. The median overall survival in our study, was 48 months [37-58].Seventy-four patients (57.9%) were diagnosed at a localized stage, 50 (40.3%) at a metastatic stage (p = 0.0001; CI: 95%). More than half of the patients, were under 50 years old, 36 were between 50 and 65 years old, and 22 were ≥ 65 years old (p = 0.8; CI: 95%). Forty-seven patients (37.6%) had a tumor located in the right breast, 67 (53.6%) in the left breast and 7 patients (5.6%) had bilateral breast cancer (p = 0.8). Seventy-nine patients (63.7%) underwent a radical mastectomy type Patey, 3 (2.4%) conservative surgery, 9 (7.3%)palliative mastectomy and 33 (26.6%) were not operated (p = 0.02; CI: 95%). The histological type was non-specific infiltrating ductal carcinoma in 93 patients (75.6%) and invasive lobular carcinoma in 14 patients(11.4%) (p = 0.04). Sixty-seven patients (53.6%) had a grade 2 and 38(30.4%) grade 3 (p = 0.08). Tumor size was T0 (0.9%), T1 (8.4%), T2 (44.9%), T3 (13.1%), T4 (32.7%) (p = 0.02). Lymph node involvement was N0 (19.4%), N1 (28.7%), N2 (35.2%), N3 (16.7%) (p = 0.054). In immunohistochemistry; 22 (45.8%) patients had a Ki67 > 20% and 26 patients (54.2%) had a Ki67 ≤ 20% with (p = 0.22). Twenty patients (16%) had a positive HER2 (p = 0.7). Seventy-one patients (61.2%) had positive hormone receptors with a median OS of 57 months [34.79] (p = 0.0001). High expression of estrogen hormone receptors (≥ 50%) had no impact on overall survival (p = 0.06) while high expression of progesterone hormone receptors was associated with better overall survival (p = 0.01). Conclusions: Breast cancer is a frequent and heterogeneous disease with several factors influencing its prognosis. The initial stage of the disease, a radical surgery, the infiltrating ductal histological type, the tumor size and the level of expression of the progesterone receptors were correlated with a better survival in our study.