Diffusion-weighted MR imaging of benign and malignant breast lesions before and after contrast enhancement.
OBJECTIVE
Many publications describe the use of diffusion-weighted imaging (DWI) in breast MRI. This article addresses the question of when to apply the DWI sequence in the course of the scan protocol. The effect of T1-shortening contrast media (CM) on the ADC values of breast lesions is investigated.


METHODS
Data were acquired on a 1.5 T scanner. 60 patients with 79 lesions (20 benign, 59 malignant) were included. The DWI sequence (4 mm slice thickness, b-values: 50, 400, 800) was applied before and after CM administration. Before calculating the ADC map, the b50, b400 and b800 series were analyzed concerning lesion displacement. ADC values before and after CM application were compared.


RESULTS
The mean lesion size was 1.5 ± 0.8 cm. On the basis of the b50 and b400 measurements, the mean ADC value of benign lesions was 1.89 ± 0.30 × 10-3 mm2/s before and 1.85 ± 0.28 ×10-3 mm2/s after CM administration. The consecutive values for two pure mucinous carcinomas were 1.88 × 10-3 mm2/s and 1.81 × 103 mm2/s and for the remaining malignant lesions 1.00 ± 0.18 × 10-3 mm2/s and 0.88 ± 0.21 × 10-3 mm2. On the basis of the b50, b400 and b800 measurements, the mean ADC value of benign lesions was 1.99 ± 0.37 × 10-3 mm2/s before and 1.97 ± 0.30 × 10-3 mm2/s after CM application, whereas the mean ADC value of the malignant lesions was 0.90 ± 0.14 × 10-3 mm2/s before and 0.80 ± 0.14 × 10-3 mm2/s after CM application. While there was no significant change for benign lesions, the ADC value decrease in post-contrast malignant lesions was highly significant.


CONCLUSIONS
DWI after CM is possible and even leads to slightly better lesion discrimination between benign and malignant. However, further studies need to be performed to verify this. Citation Format: • Janka R, Hammon M, Geppert C et al. Diffusion-Weighted MR Imaging of Benign and Malignant Breast Lesions Before and After Contrast Enhancement. Fortschr Röntgenstr 2014; 186: 130 - 135.
Department of Radiology, University Hospital Erlangen.
R
R
Janka
Department of Radiology, University Hospital Erlangen.
M
M
Hammon
Healthcare Sector, Siemens AG, Erlangen.
C
C
Geppert
Department of Radiology, University Hospital Erlangen.
A
A
Nothhelfer
Department of Radiology, University Hospital Erlangen.
M
M
Uder
Department of Radiology, University Hospital Erlangen.
E
E
Wenkel
D000328:Adult; D001943:Breast Neoplasms / Q000473:pathology*; D003287:Contrast Media / Q000008:administration & dosage; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol