5-Year Survival Rates and Prognostic Factors in Patients with Synchronus and Metachronus Breast Cancer from 2010 to 2015

Abstract

Introduction: Currently breast (BC) cancer is a serious medical problem in all countries of the world. Survival<br />depends on many factors. The present study focused on 5-year survival and its related factors in patients with BC in<br />Iran. Material and methods. The present analytical retrospective study was performed (from March 2010 until March<br />2015) on patients with BC followed for at least 6 months. The main variables assessed were tumor size, grade of lymph<br />node involvement, metastasis, stage, history, human epidermal growth factor receptor expression, and tumor origin.<br />Analysis of survival was accomplished using the Kaplan- Meier method. Results: Some 351 (80.2%) of the total of<br />438 individuals had unilateral and 87(19.8%) had bilateral cancer, 28 (35.6%) of the latter being synchronous and<br />56(64.4%) metachronous. Mean duration of follow-up was 47.44±28.19 months, during which 61 (17.3%) patients<br />with unilateral and 18 with bilateral cancer eventually died. The 5-year survival rate in patients with unilateral BC was<br />significantly higher than those with bilateral BC (Log-rank Test chi2= 3.11, p=0.032). In addition, with metachronous<br />cases, the survival rate was 64.2% in comparison with 51.6% for synchronous BCs. Survival rate was significantly<br />(p value =0.038) higher with metachronous than with synchronous cancers (Log-rank Test chi2=3.54, p=0.038). The<br />highest survival rate was reported for BCs originating from lobule tissue and the lowest rate examples of interstitial<br />tissue origin (Log-rank Test chi2=11.54, p=0.0001). Patients with earl stage lesions (M1) survived longer than with<br />other stages (Log-rank Test chi2= 9.55, p=0.001). Conclusion: In this study, most women with BC had a positive<br />family history and were married. The 5-year survival rate was lower with advanced stages of cancer. According to our<br />findings, survival rates might improve if patients undergo screening and diagnosis is made at an early stage of the disease.