CORRELATION BETWEEN ONCOTYPEDX AND CLINICOPATHOLOGICAL CRITERIA IN HORMONE RECEPTOR POSITIVE AND HER-2 NEGATIVE EARLY BREAST CANCER

Introduction: OncotypeDX is a molecular test of considerable cost, capable of providing prognostic stratification and predicting breast cancer patients who may benefit from the use of adjuvant chemotherapy. Objetive: Describe and correlate clinicopathological charactherists of patients with OncotypeDX score. Method: Data from medical records of women over 18 years diagnosed with early breast cancer between 2012 and 2022, stage T1-T2, hormone receptor positive, HER2 negative, with no axillary lymph node involvement or up to three positive lymph nodes, submitted to OncotypeDX after surgery. Statistical analyzes were performed in SPSS v.25, categorical variables were represented by absolute and relative frequency, represented by mean and standard deviation, median and interquartile range (median [P25;P75]) and amplitude (minimum and maximum). Results: From 155 patitents, the median age was 50.8 years, 51.3% were premenopausal and 30.5% underwent chemotherapy. The most used regimen was docetaxel plus cyclophosphamide for 6 cycles. OncotypeDX value ranged from 0-60. Among patients, 119 had tumors smaller than 2 cm and 134 patients had no lymph node involvement. Regarding clinical risk, 116 patients showed low clinical risk. The proportion of patients with histological grade 1, 2 and 3 tumors were 18.2%, 66.9% and 14.9%, respectively. Breast cancer recurrence occurred in 14 patients, whom only 4 underwent adjuvant chemotherapy. In Pearson’s correlation test, estrogen and progesterone receptors showed an inverse correlation with OncotypeDX, that is, the smaller the receptor (R=-0.238 and R=-0.500 respectively) the higher the OncotypeDX score. In relation to Ki-67, it presented a moderate correlation (R=0.450) and the tumor size in millimeters presented a weak correlation (R=0.236) with OncotypeDX score. The histological grade and angiolymphatic invasion tended to be significant (P=0.064 each) when correlated with the OncotypeDX score, in the analysis of variance (ANOVA) with Tukey’s post-hoc test. Smoking, body mass index and menopausal status were not significant for the purposes of this analysis. Conclusion: The result of OncotypeDX score led to the use of adjuvant chemotherapy in 30.5% of patients. It was observed an inverse correlation between estrogen and progesterone receptors, that is, the smaller the receptors, the higher the OncotypeDX score. Angiolyphatic invasion and histologic grade were more likely to correlate with elevated OncotypeDX values.