<abstract xmlns="http://www.w3.org/1999/xhtml"><sec><h3>Background</h3><p>The aim, of the study was to estimate the accuracy of magnetic resonance imaging (MRI) in assessing residual disease in breast cancer patients receiving neoadjuvant chemotherapy (NAC) and to identify the clinico-pathological factors that affect the diagnostic accuracy of breast MRI to determine residual tumour size following NAC.</p></sec><sec><h3>Patients and methods</h3><p>91 breast cancer patients undergoing NAC (92 breast lesions) were included in the study. Breast MRI was performed at baseline and after completion of NAC. Treatment response was evaluated by MRI and histopathological examination to investigate the ability of MRI to predict tumour response. Residual tumour size was measured on post-treatment MRI and compared with pathology in 89 lesions. Clinicopathological factors were analyzed to compare MRI-pathologic size differences.</p></sec><sec><h3>Results</h3><p>The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosing invasive residual disease by using MRI were 75.00%, 78.57%, 88.89%, 57.89%, and 76.09% respectively. The Pearson’s correlation coefficient (r) between tumour sizes determined by MRI and pathology was r = 0.648 (p &lt; 0.001). The size discrepancy was significantly lower in cancers with initial MRI size ≤ 5 cm (p = 0.050), in cancers with high tumour grade (p &lt; 0.001), and in patients with hormonal receptor-negative cancer (p = 0.033).</p></sec><sec><h3>Conclusions</h3><p>MRI is an accurate tool for evaluating tumour response after NAC. The accuracy of MRI in estimating residual tumour size varies with the baseline MRI tumour size, the tumour grade and the hormonal receptor status.</p></sec></abstract>

BackgroundThe aim, of the study was to estimate the accuracy of magnetic resonance imaging (MRI) in assessing residual disease in breast cancer patients receiving neoadjuvant chemotherapy (NAC) and to identify the clinico-pathological factors that affect the diagnostic accuracy of breast MRI to determine residual tumour size following NAC.Patients and methods91 breast cancer patients undergoing NAC (92 breast lesions) were included in the study. Breast MRI was performed at baseline and after completion of NAC. Treatment response was evaluated by MRI and histopathological examination to investigate the ability of MRI to predict tumour response. Residual tumour size was measured on post-treatment MRI and compared with pathology in 89 lesions. Clinicopathological factors were analyzed to compare MRI-pathologic size differences.ResultsThe overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for diagnosing invasive residual disease by using MRI were 75.00%, 78.57%, 88.89%, 57.89%, and 76.09% respectively. The Pearson’s correlation coefficient (r) between tumour sizes determined by MRI and pathology was r = 0.648 (p < 0.001). The size discrepancy was significantly lower in cancers with initial MRI size ≤ 5 cm (p = 0.050), in cancers with high tumour grade (p < 0.001), and in patients with hormonal receptor-negative cancer (p = 0.033).ConclusionsMRI is an accurate tool for evaluating tumour response after NAC. The accuracy of MRI in estimating residual tumour size varies with the baseline MRI tumour size, the tumour grade and the hormonal receptor status.

Diagnostic accuracy of MRI to evaluate tumour response and residual tumour size after neoadjuvant chemotherapy in breast cancer patients

Radiology and Oncology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

BackgroundThe aim, of the study was to estimate the accuracy of magnetic resonance imaging (MRI) in assessing residual disease in breast cancer patients...

Variable	Regression coefficient (B)	se	p	95% CI
Tumour grade	0.807	0.236	0.001	0.338-1.276
HR status	0.086	0.249	0.729	−0.408-0.581
BTS (MRI)	0.610	0.277	0.030	0.060-1.161

CONTINUOUS VARIABLES	Mean	SD	Median	Range
AGE (years)	47.22	10.10	42.0	31.0–75.0
BASAL TUMOR SIZE (cm)	3.99	1.97	3.40	1.60–13.0

		Pathology		Total
		No pCR	pCR	Total
MRI	No iCR	TP = 48	FP = 6	54 (58.70%)
MRI	iCR	FN = 16	TN = 22	38 (41.30%)
Total		64 (69.60%)	28 (30.40%)	92 (100%)

Variable	No.	Discrepancy (mean ± SD)	p-value
Age (years)
≤45	43	1.09±1.14	0.281
> 45	46	0.84 ±1.01
Baseline tumour size (cm)
≤5	74	0.85 ±0.99	0.050
>5	15	1.53 ±1.33
Histological type			0.818
ductal	83	0.97 ±1.09
lobular	6	0.87 ±0.82
Histological grade			<0.001
1 or 2	40	1.44 ±1.24
3	47	0.56 ±0.71
Hormonal receptor status			0.033
positive	59	1.14 ±1.13
negative	30	0.63 ±0.87
HER2 status			0.906
positive	24	0.99 ±1.12
negative	65	0.96 ±1.07
Molecular subtype			0.055
Luminal A	10	1.59 ±1.34
Luminal B-HER2−	34	1.05 ±1.06
Luminal B-HER2+	15	1.02 ±1.14
HER2+	9	0.92 ±1.14
Triple negative	21	0.50 ±0.70

Diagnostic accuracy of MRI to evaluate tumour response and residual tumour size after neoadjuvant chemotherapy in breast cancer patients

Article Category: Research Article

Published Online: Feb 16, 2016

Page range: 73 - 79

Received: Sep 30, 2015

Accepted: Dec 30, 2015

DOI: https://doi.org/10.1515/raon-2016-0007

Keywords
breast cancer, MRI, residual tumour, neoadjuvant chemotherapy

© 2016 Radiol Oncol

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1.

Figure 2.

Results from the Multivariate Regression Analysis

Clinical and tumour characteristics

MRI diagnostic performance in predicting pathologic response

Factors affecting the MRI diagnostic accuracy based on the discrepancy between MRI and pathologic residual tumour size

Diagnostic accuracy of MRI to evaluate tumour response and residual tumour size after neoadjuvant chemotherapy in breast cancer patients

Article Category: Research Article

Published Online: Feb 16, 2016

Page range: 73 - 79

Received: Sep 30, 2015

Accepted: Dec 30, 2015

DOI: https://doi.org/10.1515/raon-2016-0007

Keywordsbreast cancer, MRI, residual tumour, neoadjuvant chemotherapy

© 2016 Radiol Oncol

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Figure 1.

Figure 2.

Results from the Multivariate Regression Analysis

Clinical and tumour characteristics

MRI diagnostic performance in predicting pathologic response

Factors affecting the MRI diagnostic accuracy based on the discrepancy between MRI and pathologic residual tumour size

Keywords
breast cancer, MRI, residual tumour, neoadjuvant chemotherapy