Overall survival and disease-free survival in association with treatment protocols in breast cancer patients in 2011-2022

Abstract

The survival rate of breast cancer patients depends on a wide range of factors, including the time of diagnosis, the rate of disease progression at the time of diagnosis, tumor size, metastasis and involvement of other body organs, the patient's treatment regimen, and post-treatment care. The aim of this study is to evaluate the overall and disease-free survival in association with treatment protocols in breast cancer patients in 2011-2022. Materials and Methods: This research was a descriptive-analytical cross-sectional study, and all patients with a definitive diagnosis of breast cancer, regardless of the stage of the disease, who visited Tabriz medical centers between the April 2011 to March 2011 were included in the study (611 patients). The sampling method in this study was census. The primary outcomes of this study were the overall and disease-free survival. The overall survival was from the time of definite diagnosis of the disease to the time of death, and the disease-free survival was from the time of diagnosis to the time of the recurrence of the disease, when follow-up was done by telephone contact with the patient or family. Also, overall and disease-free survival were calculated for all patients using the Kaplan-Meier method. Cox regression analysis was used to analyze the relationship of all investigated variables with the risk of death and disease recurrence. Results: In this study, none of the demographic and background variables had a statistically significant relationship with the risk of death and recurrence of breast cancer (P > 0.05). Among the treatment variables studied, modified radical mastectomy (MRM) compared to breast-conserving surgery (BCS) (HR = 2.49; P = 0.038), tumor size between 2 and 5 compared to tumor size more than 5 (HR = 3.14; P = 0.009) and lymph node involvement (HR = 2.38; P = 0.011) had a statistically significant relationship with the risk of death. On the other hand, among the studied treatment variables, tumor size between 2 and 5 compared to tumor size more than 5 (HR = 2.32; P = 0.025) and lymph node involvement (HR = 2.13; P = 0.005) had a statistically significant relationship with the risk of recurrence. Also, among all the studied variables, the Adriamycin and Cyclophosphamide chemotherapy regimen (HR=0.08; P=0.026) and the presence of metastasis (HR = 2.56; P = 0.020) had a statistically significant relationship with the risk of recurrence of breast cancer patients.