Volumetric kinetic assessment in dynamic contrast enhanced-MRI (DCE-MRI) of breast cancer: A new method for evaluation of whole tumor enhancing pattern

Abstract

Background: At present, dynamic contrast enhancement-MRI (DCE-MRI) has immense role in diagnosis and
evaluation extent of breast cancer. As for diagnosis, evaluation pattern of kinetic enhancement in dynamic
contrast study is performed after gadolinium injection. Since each breast cancer has internal pathophysiological
variety, the kinetic enhancement patterns are supposed to be varied within each mass as well.

Objective: This study aimed to investigate characteristics and additional value of volumetric analysis of kinetic
enhancement patterns on DCE-MRI in evaluating breast cancer in Thai patients.

Methods: We retrospectively studied 52 women, 67 lesions which were histologically proven breast cancer,
using software of breast MRI and generating 3D volumetric voxels covered total tumor volume in DCE-MRI
which performed between January 2014 and December 2017. Measurement of enhancement pattern was categorized by software into percentage of part of tumor which enhanced in each pattern. Consequently, percentages of enhancement in different types were collected which allocated in type I (persistent), type II (plateau) and type III (washout) enhancements. Analysis of the kinetic pattern was done together with subgroup analysis of each type of tumor (IDC, DCIS and other subtypes of breast cancer) as well as tumor grades.

Results: The mean percentages of enhancement pattern in kinetic assessment by 3D voxels of tumor volume
showed the most common 72% type I enhancement, followed by 14.3% type III enhancement and 13.7% type II
enhancement. Subgroup analysis showed similar higher type I enhancement in both IDC (68.3%) and DCIS
(81.3%). However, there were slightly higher suspicious malignant pattern of enhancement (31.7% type II and
18.7% type III enhancements) in IDC more than DCIS as well as in high tumor grade (grade 3) more than low
tumor grade (grade 1) (37% type II and 30.7% type III enhancements), but there were no significant differences.

Conclusion: Volumetric analysis showed heterogeneity of kinetic curve enhancement patterns inside each tumor.
That means each tumor has a variety of enhancement patterns in itself and dissimilarity with others. The majority
of pattern was found as type I enhancement which was not particular for malignant, whereas there was only 28%
with suspicious kinetic enhancement patterns (type II and type III enhancements). The slightly higher suspicious
malignant pattern of enhancement (type II and III enhancements) in IDC more than DCIS along with high tumor
grade was observed, deprived of statistical significance.