[Neoadjuvant chemotherapy of breast carcinomas: what post-therapeutic (preoperative) information is provided by quantitative dynamic MRI?].
OBJECTIVE
The aim of this study was to evaluate whether quantitative changes in contrast enhancement (CE) after neoadjuvant chemotherapy (NC) are associated with histological signs of tumor regression and whether quantitative dynamic MRI (dMRI) is capable of accurately assessing preoperative tumor size compared to mammography (MG) and ultrasound (US).


METHODS
Thirty-one patients with breast cancer underwent MRI before and after NC. Dynamic CE was measured using a turbo-FLASH sequence and quantified by a two-compartment model, where two parameters, k(ep) (distribution constant rate) and A (amplitude), were calculated and color mapped.


RESULTS
When tumors had signs of histological regression in the operative specimen (n=17) decrease of the parameters A and k(ep) was significantly more marked compared to tumors without regression (n=12). The correlation between tumor size measured by dMRI and histopathology was 0.81 when areas of unspecific CE were included; when they were not included the correlation was 0.66 and tumor size was systematically underestimated. In 26 patients dMRI was retrospectively compared with MG (r=0.51; dMRI, r=0.80) and in 22 patients with US (r=0.60; dMRI, r=0.75).


CONCLUSIONS
Changes in dynamic CE are associated with histological tumor regression. Quantitative dMRI enables a valid assessment of tumor residue and is superior to MG and US. Remaining unspecific CE within the original tumor site should be considered as potentially malignant.
Wasser
K
K
Abteilung Onkologische Diagnostik und Therapie, Deutsches Krebsforschungszentrum Heidelberg, Germany. klaus.wasser@rad.ma.uni-heidelberg.de
Klein
S K
SK
Junkermann
H
H
Sinn
H P
HP
Darai
S
S
Neff
W
W
Kauczor
H U
HU
Delorme
S
S
D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D003287:Contrast Media; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008327:Mammography; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D012189:Retrospective Studies; D016217:Ultrasonography, Mammary
D003287:Contrast Media