Uğurcan BALYEMEZ, Sinan AKAY, Hatice Tuba SANAL, Mustafa TAŞAR
Cyprus Journal of Medical Sciences - 2026;11(5):409-416
BACKGROUND/AIMS: This study investigates whether quantitative magnetic resonance imaging (MRI)-derived signal measurements are associated with immunohistochemical biomarkers in breast cancer, extending beyond morphological assessment to signal-based imaging characteristics. MATERIALS AND METHODS: The study retrospectively included 63 patients with 66 breast cancer lesions, selected from an initial cohort of 415 patients based on specific inclusion criteria. MRI scans were performed using a standardized protocol, and quantitative MRI signal measurements were extracted and analysed. Histopathological data-including estrogen receptor (ER), progesterone receptor, human epidermal growth factor receptor 2 status, and Ki-67 proliferation index-were also evaluated. Statistical analyses, including correlation and regression tests, were conducted to assess associations between MRI features and immunohistochemical biomarkers. RESULTS: Weak associations were observed between pre-contrast T1 signal intensity (SI) and ER expression, and between T2 SI and the Ki-67 proliferation index (Spearman's rho=-0.17 and 0.25, respectively); neither remained statistically significant after Bonferroni correction for multiple comparisons nor after adjustment for within-patient lesion clustering. A more robust positive association was observed between the initial enhancement ratio (IER) and Ki-67 (rho=0.39, 95% confidence interval: 0.16-0.57, p=0.001), which remained statistically significant after Bonferroni correction (corrected p=0.016) and in both a single-lesion-per-patient sensitivity analysis and a cluster-robust regression. CONCLUSION: The association between IER and Ki-67 remained statistically significant after correction for multiple comparisons and after accounting for within-patient lesion clustering, suggesting that it may represent a comparatively robust exploratory imaging correlate of tumor proliferation. Associations involving T1 SI and T2 SI were weak and did not survive correction. These findings are preliminary and hypothesis-generating, underscoring the need for further studies with larger datasets to clarify the clinical relevance of quantitative MRI analysis in breast cancer evaluation.
