[Value of diffusion weighted imaging (DWI) in evaluating early response to neoadjuvant chemotherapy in locally advanced breast cancer].
OBJECTIVE
To evaluate the role and the performance of diffusion weighted imaging (DWI) for predicting the early response to neoadjuvant chemotherapy (NAC) in local advanced breast cancer (LABC) and to assess the accuracy of DWI in evaluating residual lesion after NAC.


METHODS
88 women with LABC (89 lesions) underwent DWI before and after the first and final cycle of NAC. For each patient, the apparent diffusion coefficient (ADC) values were compared between the baseline and follow-up to predict the early response to NAC. The residual tumor volumes were obtained using 3D maximum intensity projections (MIP) of DWI map, and were compared with pathological findings to assess the accuracy of DWI in detecting and measuring residual tumor. All results were proved or analyzed comparing with the data from histopathology.


RESULTS
There were 68 lesions responding to NAC, while 21 non-responders. The baseline ADC values of responders and non-responders were (1.049 +/- 0.135) x 10(-3) mm(2)/s and (1.171 +/- 0.134) x 10(-3)mm(2)/s, respectively, with a significant difference (t = -2.731, P = 0.009 < 0.01). The ADC value measured prior to treatment was (1.087 +/- 0.146) x 10(-3)mm(2)/s, and the degree of the changes in tumor volume after NAC was (70.4% +/- 55.1)%. A negative correlation was observed (r = -0.430, P = 0.025 < 0.05). In the response group, there was a significant difference in ADC value between prior to NAC and 1st cycle of NAC, the final cycle of NAC, respectively (P < 0.001). While no significant differences were found in non-responders during NAC (P > 0.05). The tumor volume correlation coefficient between DWI and pathology measurements was very high (r = 0.749, P < 0.01).


CONCLUSIONS
DWI appears to provide functional information regarding changes in ADC value of tumors due to NAC. DWI may be useful in monitoring the early pathological response of tumor after the initiation of treatment and in evaluating the residual tumor after NAC.
Wang
Xiao-hong
XH
Department of Diagnostic Radiology, Cancer Hospital, Fudan University, Shanghai 200032, China.
Peng
Wei-jun
WJ
Tan
Hong-na
HN
Xin
Chao
C
Gu
Ya-jia
YJ
Tang
Feng
F
Mao
Jian
J
D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology*; D016190:Carboplatin / Q000008:administration & dosage; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000188:drug therapy / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods*; D018365:Neoplasm, Residual / Q000473:pathology*; D017239:Paclitaxel / Q000008:administration & dosage; D011446:Prospective Studies; D055815:Young Adult
D016190:Carboplatin; D017239:Paclitaxel