Assessment of Breast Cancer Response to Neoadjuvant Chemotherapy with Tumor's Size at MR Imaging / 实用放射学杂志

ABSTRACT

Objective To investigate the clinical value of tumor's longest diameter and volume in assessing pathologic response in locally advanced breast cancer treated with neoadjuvant chemotherapy(NAC).Methods A prospective study was undertaken in women undergoing NAC for locally advanced breast cancer in order to determine the ability of quantitative MRI to assess the final pathologic response. 36 cases with pathologically confirmed locally advanced breast cancer who had been undergone four courses of NAC underwent preoperative breast MRI three times during the NAC. Pathologic response was assessed according Miller & Payne grading system, of which grade 4 and 5 defined as major histological response (MHR), and grade 1 to 3 as non-major histological response (NMHR). The tumor's longest diameters and volumes in MHR were compared with those in NMHR by Mann-Whitney U test before, after the second and fourth cycle of NAC. Concordance correlation coefficient (CCC) were assessed to evaluate the agreement between the two method. Receiver operating characteristic curve (ROC) analysis was carried out to assess the clinical value of tumor size and the change rate.Results Before,after the second and the fourth cycle of NAC, the difference of tumor's longest diameters and their first change rate between MHR [(2.75±1.16) cm,(2.19±1.07) cm ,(1.58±0.75) cm and (21.70±15.09)%]respectively,and NMHR [(2.71±1.10) cm,(2.33±0.90) cm,(2.01±0.94) cm and (11.68±10.27)%] respectively were not significant(P>0.05). The second change rate of tumor's longest diameter in MHR [(39.00±15.38)% ] was significantly higher than that in NMHR[ (25.83±21.77)% ](P=0.04). Before, after the second and the fourth cycly of NAC, the differences of tumor volumes and their first change rate between MHR [ median 14.00 cm~3 ( range 2.96～83.41 cm~3 ) , median 7.31 cm~3 (range 0.05～55.35 cm~3), median 2.69 cm~3 (range 0～33.40 cm~3 ) , median 48.65% (range 33.64%～98.48%) ] and NMHR [median 4.25 cm~3 (range 4.78～106.55 cm~3), median 10.53 cm~3 (range 1.72～42.85 cm~3), median 7.56 cm~3 (range 0.68～156.58 cm~3), median 52.04% (range-35.79%～78.31%) ] were not significant. The second changing rate of tumor's volume in MHR [median 85.37% (ranged 27.52%～100%)] was significantly higher than that in NMHR [median 68.80% (ranged -289.60%～94.24%)](P=0.01). CCC was computed before and (0.82), after the second cycle (0.67) and after the fourth cycle (0.55), in all examinations pooled together (0.78).The second change rates of tumor's longest diameter and volume were equal to predict the final pathologic response, and the area under curve were 0.75 and 0.80, respectively (P=0.61). Conclusion The agreement between the tumor's longest diameters and tumor's volumes is good in all in breast carcinoma. The assessment efficacy of the change rate of tumor's longest diameter and that of volume were low.