Synthetic MRI with quantitative mappings for identifying receptor status, proliferation rate, and molecular subtypes of breast cancer

Abstract

ObjectiveTo investigate whether quantitative parameters of synthetic magnetic resonance imaging (MRI) can be used to differentiate among receptor status, proliferation rate, and molecular subtypes in patients with breast cancer. Materials and methodsThis retrospective study included patients with suspicious breast lesions who underwent breast MR examinations (including synthetic MRI) from May 2019 to Oct 2020. Quantitative parameters of synthetic MRI, including T1, T2, and proton density (PD) in the breast lesions before and after (T1-Gd, T2-Gd, and PD-Gd) contrast agent injection were obtained. The Wilcoxon rank sum was utilized to analyze the differences between the parameters and receptor status, proliferation rate, Luminal A/B, TN, and HER2-enriched. The Spearman's rank correlation test was used to analyze association between parameters among five molecular subtypes. Results115 patients who met the inclusion criteria were included. Quantitative T1, T2, PD, and T2-Gd can be used as imaging biomarkers for the different receptor status and proliferation rate of breast cancer. Among them, T2 and T2-Gd were significantly different in the molecular subtypes (P = 0.000 and P = 0.006, respectively) and can further differentiate luminal A/B breast cancers from non-luminal subtypes (P = 0.005 and P = 0.015, respectively). T1 and T2 were significantly different between triple negative (TN) and non-TN breast cancers (P = 0.004 and P = 0.024, respectively). T2 and T2-Gd values were lower for luminal A/B tumors (79.5 ms and 68.00 ms, respectively) and higher for non-luminal tumors (84.00 ms and 75.00 ms, respectively). T1 and T2 values were higher for TN tumors (1.54 × 103ms and 84.00 ms, respectively) and lower for non-TN tumors (1.39 × 103 ms and 80.00 ms, respectively). ConclusionQuantitative parameters derived from synthetic MRI mappings may provide a non-invasive biomarker for discriminating receptor status, proliferation rate, and molecular subtypes in patients with breast cancer.