ABSTRACT
<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>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.</p>
Subject(s)
Adult , Aged , Female , Humans , Middle Aged , Young Adult , Antineoplastic Combined Chemotherapy Protocols , Therapeutic Uses , Breast Neoplasms , Drug Therapy , Pathology , Carboplatin , Carcinoma, Ductal, Breast , Drug Therapy , Pathology , Carcinoma, Lobular , Drug Therapy , Pathology , Diffusion Magnetic Resonance Imaging , Methods , Neoadjuvant Therapy , Methods , Neoplasm, Residual , Pathology , Paclitaxel , Prospective StudiesABSTRACT
<p><b>OBJECTIVE</b>To assess the value of dynamic contrast-enhanced MRI (DMRI) in predicting early response to neoadjuvant chemotherapy (NAC) in patients with locally advanced breast cancer (LABC) and to assess the accuracy of MRI in evaluation of residual disease after NAC.</p><p><b>METHODS</b>Forty-three women with LABC (44 lesions, all were invasive ductal carcinoma) underwent DMRI before, after the first and final cycles of NAC. For each patient, the tumor volume, early enhancement ratio (E1), maximum enhancement ratio (Emax), and maximum enhancement time (Tmax), dynamic signal intensity-time curve were obtained during treatment. The residual tumor volumes obtained by DMRI were compared with pathological findings to assess the accuracy of DMRI.</p><p><b>RESULTS</b>After the first cycle of NAC, the mean volume of responders decreased insignificantly (P = 0.055), but after NAC, mean volume of residual tumor decreased significantly (P = 0.000). Morphological changes: 29 cases showed a concentric shrinkage pattern while 7 cases showed a dendritic shrinkage pattern. Significant differences were found in E1, Emax and Tmax between responders and non-responders (P < 0.05). After the first cycle of NAC, E1, Emax and Tmax of responders changed significantly (P < 0.001), while there was no significant change in non-responders (P > 0.05). After NAC, the dynamic signal intensity-time types were changed in responders, and tended to be significantly flattening, while no significant change was found in non-responders. The residual tumor volume correlation coefficient between MRI and pathology measurements was very high (r = 0.866, P < 0.01).</p><p><b>CONCLUSION</b>DMRI is useful to evaluate the early response to NAC in LABC. The presence and volume of residual tumor in LABC patients treated with NAC can be accurately evaluated by DMRI.</p>