The study of relationship between apparent diffusion coefficient value and maximal diameter of the breast cancer with Ki-67 expression during neoadjuvant chemotherapy / 中华放射学杂志

ABSTRACT

ObjectiveStudy the ADC value and the maximal diameter and their changes of breast cancer before and after neoadjuvant chemotherapy,to determine the relationship with different expression level of Ki-67.Methods Forty eight patients with breast cancer confirmed by biopsy underwent MR DWI and enhanced scan before and after 4 cyclesneoadjuvant chemotherapy.ReviewtheMRimages retrospectively.The ADC value and the maximum diameter( D)of the cancer foci were measured before and after chemotherapy,and the rate of their changes △ADC％ and △D％ were calculated.Using different Ki-67 index level,all the foci were divided into three groups:group A with Ki-67 ＜ 20％,group B with Ki-67 between 20％ and 60％,and group C with Ki-67 ＞ 60％.Using nonparameter test to compare the ADC values,△ADC％,D and △D％ of the three groups before and after chemotherapy,determine whether there were differences.ResultsBefore chemotherapy,the ADC value of group A ( n = 15 ) was 1.1 ×10-3 mm2/s[ (0.9 × 10-3—1.2 × 10-3) mm2/s],which was higher than that of group B[n = 8,0.9 ×10-3 mm2/s(0.9 × 10-3-1.0 × 10-3) mm2/s] and C [n =25,0.9 × 10-3 mm2/s(0.7 × 10-3—1.2 ×10-3) mm2/s],and the difference was statistically significant (P ＜0.05 ) ; while the ADC value of group C after chemotherapy was 1.3 × 10 -3 mm2/s[ (0.2 × 10 -3—1.4 × 10 -3 ) mm2/s],which was higher than that of group A [1.1 × 10-3 mm2/s,(1.0 × 10-3—1.2 × 10-3) mm2/s] and B[1.1 × 10-3 mm2/s,( 1.0 × 10-3-1.1 × 10 -3 ) mm2/s],and the differences were statistically significance ( P ＜ 0.01 ) ; the ADC change rate( △ADC％ ) of group C was 45.5％ ( - 12.0％ —78.6％ ),which was greater than group A [45.5％ ( - 12.0％—78.6％ ) ] and B [ 45.5％ ( - 12.0％—78.6％ ) ],the difference was significant (P ＜ 0.01 ).The maximum diameters of group A were 2.2 cm (2.0—2.4 cm)and 1.0 cm(0.0—1.4 cm)before and after chemotherapy,lower than those of group B [ 3.7 cm ( 3.6—3.9 cm ) before NAC,2.9 cm (0.0-3.1 em) after NAC] and group C[3.4 cm(2.7—4.2 cm) before NAC,1.9 cm(0.0—2.2 cm) after NAC ],and the differences were statistically significant ( P ＜ 0.05 ) ; the change rate of the maximum diameter in group B was 21.6％ ( - 15.2％—27.5％ ),which was less than group A [52.7％ ( -23.6％—72.1％)] (P＜0.01) and C [51.2％ ( -10.3％—92.6％)] (P ＜0.05),and the difference was statistically significant.Conclusion The ADC values and the maximal diameter of breast cancer differed with different expression levels of Ki-67 index before and after neoadjuvant chemotherapy,and the response to neoadjuvant chemotherapy of which varied as well.