Purpose: The aim of this study was to establish possible relationships among the metabolic and vascular characteristics of breast cancer using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) imaging.
Methods: Sixty-seven female patients with invasive ductal breast carcinoma (age 32-79 years) who underwent FDG PET/CT and DCE-MRI prior to cancer treatment were included in the study. The maximum standardized uptake value (SUVmax), metabolic tumor volume, total lesion glycolysis (TLG), and heterogeneity factor (HF) were derived from FDG PET/CT. The DCE-MRI parameters K trans, K ep, and V e were obtained for all tumors, and relationships between the metabolic and perfusion parameters were sought via Spearman's rank correlation analysis. The prognostic significance of clinicopathological and imaging parameters in terms of recurrence-free survival (RFS) was also evaluated.
Results: No significant correlation between perfusion and metabolic parameters (p > 0.05) was found, except between SUVmax and V e (p = 0.001, rho = -0.391). Recurrence developed in 12 of the 67 patients (17.9 %, follow-up period 8-41 months). Age (p = 0.016) and HF (p = 0.027) were significant independent predictors of recurrence-free survival (RFS) upon multivariate analysis. The RFS of patients under 40 years of age was significantly poorer than that of older patients (p < 0.001). Survival of patients with more heterogeneous tumors (HF less than -0.12) was poorer than those with relatively homogenous tumors (p = 0.033).
Conclusions: Tumors with higher levels of glucose metabolism (SUVmax values) exhibited higher tumor cellularities (V e values). Also, of the various metabolic and perfusion parameters available, tumor heterogeneity measured via FDG PET/CT (HF) may be useful in predicting RFS in breast cancer patients.