乳腺癌新辅助化疗前后MR表观扩散系数及癌灶最大径与Ki-67表达的相关性研究

目的 探讨乳腺癌患者新辅助化疗前后ADC值和癌灶最大径与Ki-67不同表达程度之间的关系.方法 回顾性分析48例穿刺活检证实为乳腺癌的患者资料,患者于新辅助化疔前及化疗第4周期后行MR DWI及增强扫描.测量化疗前后癌灶的ADC值及最大径,并计算其变化率△ADC％和△D％.利用Ki-67指数不同,将所有癌灶分为A、B、C三组:A组Ki-67＜ 20％,B组Ki-67为20％ ～ 60％,C组Ki-67＞ 60％.采用非参数检验比较3组癌灶化疗前后ADC值、△ADC％、最大径及△D％的差异.结果 化疗前A组(15例)癌灶的ADC值为1.1 × 10-3 mm2/s[(0.9×10-3～1.2×10-3)mm2/s],高于B组[8例,0.9×10-3 mm2/s(0.9×10-3～1.0×10-3) mm2/s]和C组[25例,0.9×10-3mm2/s(0.7 × 10-3～1.2×10-3)mm2/s],差异有统计学意义(P＜0.05)；而化疗后C组癌灶的ADC值为1.3×10-3 mm2/s[(0.2×10-3 ～ 1.4×10-3)mm2/s],高于A组[1.1×10-3 mm2/s,(1.0× 10-3 ～ 1.2×10-3)mm2/s]和B组[1.1×10-3 mm2/s(1.0×10-3～1.1×10-3)mm2/s],差异具有统计学意义(P＜0.01)；化疗前后C组癌灶的ADC变化率为45.5％(- 12.0％～78.6％),大于A组[45.5％(- 12.0％ ～ 78.6％)]和B组[45.5％(- 12.0％～78.6％)],差异具有统计学意义(P＜0.01).化疗前、后癌灶的最大径A组分别为2.2 cm(2.0～2.4 cm)和1.0 cm(0.0～ 1.4 cm),均小于B组[化疗前3.7 cm(3.6～3.9 cm),化疗后2.9 cm(0.0 ～3.1 cm)]和C组[化疗前3.4 cm(2.7 ～4.2 cm),化疗后1.9 cm(0.0 ～2.2 cm)],且差异具有统计学意义(P＜0.05)；B组癌灶化疗后最大径的变化率为21.6％(- 15.2％ ～ 27.5％),小于A组[52.7％(-23.6％ ～72.1％)](P＜0.01)和C组[51.2％(- 10.3％～92.6％)](P＜0.05),差异具有统计学意义.结论 对于Ki-67指数不同表达程度的癌灶,新辅助化疗前、后癌灶的ADC值不同,癌灶的ADC值及最大径线对于化疗的反应不同,差异具有统计学意义.

The study of relationship between apparent diffusion coefficient value and maximal diameter of the breast cancer with Ki-67 expression during neoadjuvant chemotherapy

Objective Study 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 cycles neoadjuvant chemotherapy.Review the MR images 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.