Oxidative stress prognostic value and importance in breast cancer

"OXIDATIVE STRESS PROGNOSTIC VALUE AND IMPORTANCE IN BREAST CANCER" INTRODUCTION AND AIM: Breast cancer is the most common cancer among women in Turkey and in the world. It constitutes approximately 25% of all cancers in women in Turkey. In breast cancer, which is a systemic disease, it is important to determine the staging of the patients, prognostic factors. Axillary lymph node positivity is the strongest prognostic factor. Clinically, studies have been conducted to find other predictors of prognosis in axillary negative patients. The purpose of this study is; Total Antioxidative Status (TAS), Total Oxidative Status (TOS) and Oxidative Stress Index (OSI) in patients with breast cancer with TAS, TOS and OSI levels of healthy women. Secondary is to differentiate TAS, TOS and OSI values before and after treatment. Our tertiary goal; The aim of this study was to investigate the efficacy of chemotherapy on these biological factors by looking at serum levels of these values before and after neoadjuvant chemotherapy and to evaluate whether serum levels of these factors are predictors of neoadjuvant chemotherapy response predicted. Another aim is to investigate the efficacy of these markers in predicting sentinel lymph node positivity in axillary negative patients clinically. METHOD AND MATERIAL: A total of 45 breast cancer patients and 46 healthy women's blood samples were collected in the clinic of Sakarya University Training and Research Hospital General Surgery Department. Neoadjuvant Blood samples were taken three times before chemotherapy, preoperative and post-operatively in 11 patients receiving chemotherapy, and before and after surgery in patients who did not receive chemotherapy. TAS and TOS values were measured in the sera of these patients and OSI was calculated. Age, body mass index (BMI), obesity, CA15-3, D vitamine level, presence of metastatic lymph node, tumor diameter, histological type, grade, stage, estrogen and progesterone receptor, cerbB2, subtypes were evaluated as clinicopathologic parameters. The data were evaluated on a computer-based IBM SPSS 21.0 program. Because our results are non homogeneous distribution; Mann-Whitney-U and Kruskal-Wallis used the Spearman's correlation test, the ROC graph for the threshold value, and the Chi-square test for the comparison of clinicopathologic parameters with serum positivity. FINDINGS: Serum values of forty-five breast cancer patients were compared with control group and clinicopathologic parameters. In patients with breast cancer, serum TOS and OSI values are higher than healthy women and TAS values are lower before treatment. It was seen that TAS values of obese patients were higher than normal weight patients. In patients with progesterone receptor positive, lymphatic invasion and metastatic breast cancer, TOS and OSI values were higher than patients without negative lymph node invasion and without metastasis. In triple negative patients, TOS and OSI values were higher than the other types. No correlation was found in the correlation analysis between age, CA 15-3, D vitamine level, presence of clinical lymph node metastasis, estrogen receptor positivity, C-B2 receptor positivity, grade, tumor size, extracapsular invasion and vascular invasion and TOS, TAS and OSI. There was no significant difference in TOS, OSI values before and after neoadjuvant chemotherapy and after operation. However, TAS levels increased after neoadjuvant chemotherapy and after surgery. CONCLUSION: As a result, TOS and OSI values are higher in breast cancer patients than healthy women and TAS is lower in breast cancer patients than healthy women. High levels of TOS and OSI in stage 4 and triple negative tumors indicate more oxidative stress in more aggressive tumors.With chemotherapy, tumor shrinks and / or disappears, and surgical removal of the tumor improves TAS values. TOS, TAS and OSI values can be used as a marker for discrimination between healthy women and patients with breast cancer. The high availability of this area will be demonstrated along with its usefulness as a prognostic marker in breast cancer. Key Words: Breast cancer, TAS, TOS, OSI, prognostic factor