Accuracy of tumor size measurements performed by magnetic resonance, ultrasound and mammography, and their correlation with pathological size in primary breast cancer

Abstract

Introduction: The objective of this study was to determine which image test used to measure the size of pre-operative primary breast cancer (mammography, ultrasound or magnetic resonance imaging [MRI]) correlated best with the size of the tumor in the postoperative surgical specimen.

Methods: A retrospective analysis was conducted of women diagnosed with breast cancer for which primary surgical treatment was indicated and who underwent surgical intervention between January 2014 and December 2016. Sociodemographic, imaging and histological variables were collected. The results are presented by age group, tumor size and histological type.

Results: In the 224 women studied, mammography and MRI tumor sizes were compared with pathology study tumor measurements, revealing no significant differences, both overall and based on histologic type or age. However, both significantly underestimated large tumors and significantly overestimated small tumors. Ultrasound significantly underestimated tumor size, especially in large tumors, older patients and in infiltrating ductal carcinoma (IDC) and infiltrating ductal carcinoma with associated ductal carcinoma in situ (IDC+DCIS). MRI correlated best with histological tumor size, although with no statistically significant differences.

Conclusions: MRI is the best predictor of tumor size in breast cancer. Histologic type and tumor size are key parameters when estimating tumor size and should be taken into account when planning surgery. Patient age does not interfere with the interpretation of imaging tests.

Keywords: Breast cancer; Cirugía; Cáncer de mama; Ecografía; Histología; Magnetic resonance imaging; Mammography; Mamografía; Pathology; Resonancia magnética; Surgery; Tamaño tumoral; Tumor size; Ultrasound.