[Disease-free survival of breast cancer patients and identification of related factors]

ABSTRACT

Breast cancer is the most common cancer among women especially in eastern Mediterean region. Disease-free survival is common to evaluate the treatment of cancers. Several factors have been determined as prognostic factors for disease-free survival in studies. In this cross-sectional study, during 2005-2007, 153 women with breast cancer were treated in Fayazbakhsh hospital, Tehran. These patients had no metastasis at the time of diagnosis. Patients underwent MRM or BCS surgery. All patients followed until 2011 April. Metastases were diagnosed with x-ray, Biochemical methods, ultrasound with oncologist confirmation. A Cox's regression with time to first event variable was used to determine the prognostic factors. Kaplan-Myer method was used to estimate the survival function. All statistical methods ran in R software version 2.10. Out of 133 patients, 25[18.8%] died and 108[81.2%] were alive. Out of alive patients, 99[74.4%] without metastasis and 9 patients[6.8%] experienced a metastasis. Using Kaplan-Myer estimation showed that disease-free survival was 64 months, and five years rate of disease-free was 72 percent. Increasing in disease-free survival was associated with low grade of tumor, low number of involved lymph nodes, ER negative and HER2 negative. Odds ratio of metastasis or death for HER2 positive was 2.46 times of HER2 negative. Patients with grade 3 had risk of metastasis 1.69-fold of grade2. The result of this study showed that HER2, ER, Grade and number of involved lymph nodes were prognostic factors. Age, size of tumor and PR were not identified as prognostic factors