Comparison of mammography, sonography, MRI and clinical examination in patients with locally advanced or inflammatory breast cancer who underwent neoadjuvant chemotherapy

Abstract

Objectives: The purpose of this study was to determine the relative accuracies of mammography, sonography, MRI and clinical examination in predicting residual tumour size and pathological response after neoadjuvant chemotherapy for locally advanced or inflammatory breast cancer. Each prediction method was compared with the gold standard of surgical pathology.

Methods: 43 patients (age range, 25-62 years; mean age, 42.7 years) with locally advanced or inflammatory breast cancer who had been treated by neoadjuvant chemotherapy were enrolled prospectively. We compared the predicted residual tumour size and the predicted response on imaging and clinical examination with residual tumour size and response on pathology. Statistical analysis was performed using weighted kappa statistics and intraclass correlation coefficients (ICC).

Results: The ICC values between predicted tumour size and pathologically determined tumour size were 0.65 for clinical examination, 0.69 for mammography, 0.78 for sonography and 0.97 for MRI. Agreement between the response predictions at mid-treatment and the responses measured by pathology had kappa values of 0.28 for clinical examination, 0.32 for mammography, 0.46 for sonography and 0.68 for MRI. Agreement between the final response predictions and the responses measured by pathology had kappa values of 0.43 for clinical examination, 0.44 for mammography, 0.50 for sonography and 0.82 for MRI.

Conclusion: Predictions of response and residual tumour size made on MRI were better correlated with the assessments of response and residual tumour size made upon pathology than were predictions made on the basis of clinical examination, mammography or sonography. Thus, the evaluation of predicted response using MRI could provide a relatively sensitive early assessment of chemotherapy efficacy.

Figure 1

A 30-year-old woman with a palpable lump in the upper outer quadrant of the right breast. (a) The initial mediolateral oblique mammogram shows an approximately 6 cm mass with pleomorphic calcifications (encircled) in the upper outer quadrant of the right breast. Serial follow-up mammograms after (b) four and (c) eight cycles of chemotherapy show the decreased size of the large malignant mass, but also show remaining pleomorphic calcifications with segmental distribution (arrows). This was considered to be a partial response. (d) The initial sonogram shows a 4.2 cm mass with calcifications in the right breast. Two serial follow-up sonograms after (e) four and (f) eight cycles of chemotherapy show that the size of the mass has decreased markedly, but a vague mass with calcifications remains (arrows). This was considered to be a partial response. (g) A maximum intensity projection image on the initial MRI shows an approximately 5 cm enhancing mass in the right breast. Two serial follow-up MRI images after (h) four and (i) eight cycles of chemotherapy show no residual enhancing lesion in the right breast. This was interpreted as complete response on MRI. Surgery confirmed a 0.1-cm ductal carcinoma in situ, which indicated a pathological complete response.