Preoperative dynamic breast magnetic resonance imaging kinetic features using computer-aided diagnosis: Association with survival outcome and tumor aggressiveness in patients with invasive breast cancer

Abstract

Objectives: To evaluate whether preoperative breast dynamic contrast-enhanced (DCE) magnetic resonance (MR) imaging kinetic features, assessed using computer-aided diagnosis (CAD), can predict survival outcome and tumor aggressiveness in patients with invasive breast cancer.

Materials and methods: Between March and December 2011, 301 women who underwent preoperative DCE MR imaging for invasive breast cancer, with CAD data, were identified. All MR images were retrospectively evaluated using a commercially available CAD system. The following kinetic parameters were prospectively recorded for each lesion: initial peak enhancement, the proportion of early phase medium and rapid enhancement, and the proportion of delayed phase persistent, plateau, and washout enhancement. The Cox proportional hazards model was used to determine the association between the kinetic features assessed by CAD and disease-free survival (DFS). The peak signal intensity and kinetic enhancement profiles were compared with the clinical-pathological variables.

Results: There were 32 recurrences during a mean follow-up time of 55.2 months (range, 5-72 months). Multivariate analysis revealed that a higher peak enhancement (DFS hazard ratio, 1.004 [95% confidence interval (CI): 1.001, 1.006]; P = .013) on DCE MR imaging and a triple-negative subtype (DFS hazard ratio, 21.060 [95% CI: 2.675, 165.780]; P = .004) were associated with a poorer DFS. Higher peak enhancement was significantly associated with a higher tumor stage, clinical stage, and histologic grade.

Conclusions: Patients with breast cancer who showed higher CAD-derived peak enhancement on breast MR imaging had worse DFS. Peak enhancement and volumetric analysis of kinetic patterns were useful for predicting tumor aggressiveness.

Fig 1. Magnetic resonance (MR) images with computer-aided detection (CAD) Color Overlay Map in a 66-year-old Woman with grade 2 invasive ductal carcinoma in the left breast.

(A) Axial contrast-enhanced T1-weighted MR image shows a 26-mm irregular mass (arrows). (B) Axial maximum-intensity-projection MR image shows CAD color overlay over the breast mass. L1 denotes the first lesion of the left breast. Areas in red, yellow, and blue indicate a rapid washout-type delayed enhancement, plateau-type delayed enhancement, and persistent-type delayed enhancement pattern, respectively. (C) Kinetic curve graph showing rapid initial enhancement and rapid washout-type curve. The initial peak enhancement value was 559%. With respect to the delayed phase enhancement, 9% of the mass showed washout, 50% of the mass showed a persistent-type curve, and 41% showed a plateau-type curve. Regional recurrence was diagnosed in the ipsilateral axillary lymph node 26 months after surgery.

Fig 2. Magnetic resonance (MR) Images with Computer-aided detection (CAD) Color Overlay Map in a 71-year-old Woman with grade 2 invasive ductal carcinoma in the right breast.

(A) Axial contrast-enhanced T1-weighted MR image shows a 15-mm irregular mass (arrows). (B) Axial maximum-intensity-projection MR image shows a CAD color overlay over the breast mass. R1 denotes the first lesion of the right breast. Areas in red, yellow, and blue indicate rapid washout-type delayed enhancement, plateau-type delayed enhancement, and persistent-type delayed enhancement patterns, respectively. (C) Graph of the kinetic curve shows rapid initial enhancement and rapid washout-type curve. The initial peak enhancement value was 119%. With respect to the delayed phase enhancement, 39% of the mass showed washout, 4% of the mass showed a persistent-type curve, and 58% showed a plateau-type curve. There was no recurrence during the 65-month follow-up period.