Mutual evaluation of major prognostic and predictive factors in breast cancer

Aim: In this study, we aim to investigate some basic prognostic and predictive factors that shown to have a decisive influence on the treatment process, and these factors' relations between each other at the follow-up patients with breast cancer. Also we aim to investigate human epidermal growth factor receptor-2 status, which is currently considered to be the most effective prognostic and predictive factor, it's correlation with different methods and assessing the adequacy about human epidermal growth factor receptor-2 status in our center and the impact of these results on the treatment choice decision. Methods: Breast cancer patients, whose diagnosis, treatment and follow-up stages performed in Adnan Menderes University Faculty of Medicine, Department of Internal Medicine, Division of Medical Oncology, enrolled in this study. After receiving informed consent forms from study patients, their clinical (age, size, stage of disease, date of diagnosis, treatments, final situation and date of recurrence development) and pathological (tumor type, size, lymph node involvement, grade, lymphovascular invasion status, p53, Ki-67, human epidermal growth factor receptor-2, estrogen receptor, progesterone receptor) features were obtained from the archive. Results: Involvement of axillary lymph node status was significantly correlated with tumor size and lymphovascular invasion. The presence of lymphovascular invasion was positively correlated with the size of tumor. We detected a positive correlation between age and hormone receptor status, and a negative correlation between hormone receptor and human epidermal growth factor receptor-2. We found no significant relationship between tumor size and involvement of node status and hormone receptore with human epidermal growth factor receptor-2. There was no significant relationship between Ki-67 index and the grade score. We did not detect any significant relationship between Ki-67 index and grade score with nodal involvement, tumor size, age, hormone receptor status, human epidermal growth factor receptor-2 status. We compared human epidermal growth factor receptor-2 (+3) patients with (+1) patients immunohistochemically. We observed test sensitivity 92%, false-negativity 8%, specificity 55%, false positivity 45%, positive predictive value 52%, negative predictive value 90%, accuracy 64%. We found Chromogenic in situ hybridization assay's sensitivity 67%, false-negativity 33%, specificity 87%, false-positivity 13%, positive predictive value 71%, negative predictive value 86% and accuracy 82%. Conclusion: We considered Human epidermal growth factor receptor-2 results with the method of Ki-67 index, grade score, immunohistochemistry and chromogenic in situ hybridization. Examination of the technical process, close cooperation between the clinician and pathologist shall be useful from the time of tissue sampling. Chromogenic in situ hybridization assay is not suitable for use alone. Chromogenic in situ hybridization assay should be used with FISH method until sufficient experience is obtained.