Effect of taxane-based neoadjuvant chemotherapy on fibroglandular tissue volume and percent breast density in the contralateral normal breast evaluated by 3T MR.
The aim of this study was to evaluate the change of breast density in the normal breast of patients receiving neoadjuvant chemotherapy (NAC). Forty-four breast cancer patients were studied. MRI acquisition was performed before treatment (baseline), and 4 and 12 weeks after treatment. A computer-algorithm-based program was used to segment breast tissue and calculate breast volume (BV), fibroglandular tissue volume (FV), and percent density (PD) (the ratio of FV over BV × 100%). The reduction of FV and PD after treatment was compared with baseline using paired t-tests with a Bonferroni-Holm correction. The association of density reduction with age was analyzed. FV and PD after NAC showed significant decreases compared with the baseline. FV was 110.0 ml (67.2, 189.8) (geometric mean (interquartile range)) at baseline, 104.3 ml (66.6, 164.4) after 4 weeks (p < 0.0001), and 94.7 ml (60.2, 144.4) after 12 weeks (comparison with baseline, p < 0.0001; comparison with 4 weeks, p = 0.016). PD was 11.2% (6.4, 22.4) at baseline, 10.6% (6.6, 20.3) after 4 weeks (p < 0.0001), and 9.7% (6.2, 17.9) after 12 weeks (comparison with baseline, p = 0.0001; comparison with 4 weeks, p = 0.018). Younger patients tended to show a higher density reduction, but overall correlation with age was only moderate (r = 0.28 for FV, p = 0.07, and r = 0.52 for PD, p = 0.0003). Our study showed that breast density measured from MR images acquired at 3T MR can be accurately quantified using a robust computer-aided algorithm based on non-parametric non-uniformity normalization (N3) and an adaptive fuzzy C-means algorithm. Similar to doxorubicin and cyclophosphamide regimens, the taxane-based NAC regimen also caused density atrophy in the normal breast and showed reduction in FV and PD. The effect of breast density reduction was age related and duration related.
Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA, USA; Department of Radiology, E-Da Hospital and I-Shou University, Kaohsiung, Taiwan.
Jeon-Hor
JH
Chen
Wei-Fan
WF
Pan
Julian
J
Kao
Jocelyn
J
Lu
Li-Kuang
LK
Chen
Chih-Chen
CC
Kuo
Chih-Kai
CK
Chang
Wen-Pin
WP
Chen
Christine E
CE
McLaren
Shadfar
S
Bahri
Rita S
RS
Mehta
Min-Ying
MY
Su
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001940:Breast / Q000187:drug effects / Q000473:pathology*; D001943:Breast Neoplasms / Q000188:drug therapy*; D001952:Bridged-Ring Compounds / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009929:Organ Size / Q000187:drug effects; D043823:Taxoids / Q000494:pharmacology / Q000627:therapeutic use*
D014408:Biomarkers, Tumor; D001952:Bridged-Ring Compounds; D043823:Taxoids; C080625:taxane
3T MR; MRI; breast density; fibroglandular tissue volume; neoadjuvant chemotherapy; normal breast; percent density; taxane