The Clinical Study On Functional MRI In Assessment Of Early Response To Neoadjuvant Chemotherapy In Breast Carcinoma

Part one The value of dynamic contrast-enhanced MRI in assessment of early response to neoadjuvant chemotherapy in breast cancerObjective:To assess the value of dynamic contrast-enhanced magnetic resonance imaging(MRI) in predicting early response to neoadjuvant chemotherapy(NAC) in patients with locally advanced breast cancer(LABC) and to assess the accuracy of MRI in evaluating residual disease after NAC.Materials and methods:Forty-three women with LABC(44 lesions,all were invasive ductal carcinoma) underwent MRI mammography before,after the first and final cycle of NAC.Dynamic contrast-enhanced MRI was performed on a 1.5 T unit.For each patient,tumour volume,early enhanced ratio,maximum enhanced ratio,and maximum enhanced time, dynamic signal intensity-time curve were obtained during treatment.Residual tumour volumes obtained using MRI were compared with pathological findings to assess the accuracy of MRI in detecting and in measuring residual tumour.Results:(1) After 1^st cycle of NAC,the mean volume of responders decreased 1.2±3.1cm³, t=2.005,P=0.055,but after NAC,mean volume of residual tumor decreased significantly..(t=6.926,P=0.000)(2) morphology change:29 cases showed a concentric shrinkage pattern while 7 cases showed a dendritic shrinkage pattern. There is no significant correlation between type of tumor shrinkage and ER/PR. (P＞0.05)(3) Significant differences were found in early enhanced ratio,maximum enhanced ratio and maximum enhanced time between responders and non-responders. (P＜0.05).(4),After 1^st cycle of NAC,early enhanced ratio,maximum enhanced ratio and maximum enhanced time of responders changed significantly(P＜0.001);while there is no significant change in non-responders.(P＞0.05)(5),After NAC,dynamic signal intensity-time types were changed in responders,and tended to be significantly flattening,while no significant change was found in non-responders.(6).The residual tumour volume correlation coefficient between MRI and pathology measurements was very high:(r=0.866,P=0.000).Conclusion:Dynamic contrast-enhanced MRI is useful to evaluate the early response to NAC in LABC.The presence and volume of residual disease in LABC patients treated with NAC could be accurately evaluated by MRI.Part two Diffusion weighted Imaging(DWI) in evaluating early response to neoadjuvant chemotherapy in locally advanced breast cancerObjective:To evaluate the role and the performance of Diffusion weighted Imaging (DWI) for predicting the response to locally advanced breast cancer(LABC) early after the initiation of neoadjuvant chemotherapy(NAC),and to assess the accuracy of DWI in evaluating residual disease after NAC.Materials and methods:88 women with LABC(89 lesions,including 86 invasive ductal carcinoma,1 mutinous adeocarcinoma and 2 invasive lobular carcinoma) underwent Diffusion-weighted Imaging(DWI) before,after the first and final cycle of NAC.DWI was performed on a 1.5 T MR scanner.For each patient,the Apparent Diffusion Coefficient(ADC) values were calculated using b=1000s/mm2.Residual tumour volumes obtained using 3D Maximum Intensity Projections(MIP) of DWI map were compared with pathological findings to assess the accuracy of DWI in detecting and in measuring residual tumour.All were proved by histopathology.Results:1,There were 68 lesions responding to NAC,while 21 non-responders.2,Significant difference was found in ADC value between responders and non-responders.(t=-2.731,P=0.009＜0.01).There was a significant negative correlation between the ADC value before NAC and change of ADC after 1st cycle of NAC.(r=-0.394,P=0.000＜0.001);A negative correlation was also observed between the ADC values measured prior to treatment, and the degree of the changes in tumor volume after NAC(r=-0.430,P=0.025＜0.05). 3.In response group,there was 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＞0.05.4.The tumour volume correlation coefficient between DWI and pathology measurements was very high,r=0.749,P=0.000＜0.001.Conclusion:DWI appears to provide functional information regarding changes in ADC value of tumors due to NAC.DWI may be useful in monitoring tumor pathological response early after the initiation of treatment and in evaluating the residual tumor after NAC. Part three Evaluation of total choline from in-vivo volume localized proton MR spectroscopy and early response to neoadjuvant chemotherapy in locally advanced breast cancerObjective:To evaluate proton Magnetic Resonance Spectroscopy(¹H-MRS) in diagnosis of breast carcinoma and detecting early response to neoadjuvant chemotherapy(NAC) in locally advanced breast cancer(LABC).Materials and Methods:The study included 98 patients with LABC(totally 99 lesions,98 invasive ductal carcinoma,1 mucinous carcinoma) undergoing NAC.Magnetic resonance imaging and ¹H-MRS were carried out before and after the first cycle of treatment. Lesion tCho concentration was quantified by using single-voxel hydrogen 1 MR spectroscopy.The peak height,area under curve and signal-noise ratio of tCho were measured.We compared the results between the baseline and follow-up to predict early response to NAC.All cases were proved by histopathology.Results:(1) In-vivo ¹H-MRS was successfully performed in 83 patients(83.8%,83/99).The sensitivity of detecting TCho(choline-containing compounds) in LABC was 75.9%(63/83).(2) There is no significant correlation between Cho and ER/PR.(χ² = 0.028,P=0.866)(3) Significant differences were found in the peak height,area under curve and signal-noise ratio of tCho between responders and non-responders.(P＜0.05).(4),After 1st cycle of NAC,the peak height,area under curve and signal-noise ratio of tCho in responders changed significantly(P＜0.001);while there is no significant change in non-responders(P＞0.05).After 1st cycle of treatment,the peak amplitude of composite choline in responders were decreased or vanished.Conclusion: ¹H-MRS can detect breast carcinoma.Observation of TCho before treatment and its disappearance(or reduction) after treatment may be a useful indicator of response to NAC in LABC. Part four Evalution of T2^*-Weighted First Pass Perfusion MR imaging in assessment of early response to neoadjuvant chemotherapy in locally advanced breast cancerObjective:To evaluate the value of T2^*-weighted first-pass perfusion imaging (T2^*-PWI) in patients with locally advanced breast cancer(LABC) and to determine if T2^*-weighted imaging can provide additional information to predict early response to neoadjuvant chemotheapy(NAC).Materials and Methods:Forty-five patients with LABC(all were invasive ductal carcinoma) underwent T2^*-PWI.Among them, T2^*-PWI of 19 lesions were carried out before and after the second cycle of treatment. We compared the results between the baseline and follow-up to predict early response to NAC.The first-pass signal intensity loss of the lesions was calculated.All cases were proved by histopathology.Results:(1) Among 45 breast cancer,T2^*-PWI were successfully performed in 41 lesions(91.1%).The sensitivity of T2^*-PWI in detecting breast carcinoma was 87.8%(36/41),Time-intensity curve showed sharp drop of MR signal in the perfusion phase compared with pre-contrast baseline.(2) After 2 cycles of NAC,the negative enhanced integral,negative first-pass slope and maximum signal-loss ratio of LABC changed significantly(P＜0.01).The extent of signal intensity decreased and slope of perfusion curve showed gradually even after therapy. Conclusion:T2^*-PWI can help diagnose malignant breast lesions with a high level of specificity,and provide a sensitive assessment of treatment efficacy.