Objectives: To determine associations between dynamic contrast-enhanced MR imaging (DCE-MRI) parameters and survival intervals in patients with locally advanced breast cancer treated with neoadjuvant chemotherapy (NAC), surgery, and adjuvant therapies. Further, to compare the prognostic value of DCE-MRI parameters against traditional survival indicators.
Methods: DCE-MRI and MR tumour volume measures were obtained prior to treatment and post 2nd NAC cycle. To demonstrate which parameters were associated with survival, Cox's proportional hazards models (CPHM) were employed. To avoid over-parameterisation, only those MR parameters with at least a borderline significant result were entered into the final CPHM.
Results: When considering disease-free survival positive axillary nodal status (hazard ratio [HR] 6.79), younger age (HR 3.37), negative oestrogen receptor status (HR 3.24), pre-treatment Maximum Enhancement Index (MaxEI) (HR 6.51), and percentage change in MaxEI (HR 1.02) represented the retained CPHM covariates. Similarly, positive axillary nodal status (HR 11.47), negative progesterone receptor status (HR 4.37) and percentage change in AUC90 (HR 1.01) represented the retained predictive variables for overall survival.
Conclusions: Multivariate survival analysis has demonstrated that DCE-MRI parameters obtained prior to NAC and/or post 2nd cycle can provide independent prognostic information that can complement traditional prognostic indicators available prior to treatment.
Key points: • MR-derived DCE-MRI parameters obtained prior to treatment have prognostic value. • Early treatment-induced reductions in DCE-MRI parameters represents a positive prognostic indicator. • DCE-MRI parameters provide independent prognostic information that can complement traditional prognostic indicators.