Morphologic Features of Magnetic Resonance Imaging as a Surrogate of Capsular Contracture in Breast Cancer Patients With Implant-based Reconstructions

Abstract

Purpose Capsular contracture (CC) is a serious complication in patients receiving implant-based reconstruction for breast cancer. Currently, no objective methods are available for assessing CC. The goal of the present study was to identify image-based surrogates of CC using magnetic resonance imaging (MRI). Methods and Materials We analyzed a retrospective data set of 50 patients who had undergone both a diagnostic MRI scan and a plastic surgeon’s evaluation of the CC score (Baker’s score) within a 6-month period after mastectomy and reconstructive surgery. The MRI scans were assessed for morphologic shape features of the implant and histogram features of the pectoralis muscle. The shape features, such as roundness, eccentricity, solidity, extent, and ratio length for the implant, were compared with the Baker score. For the pectoralis muscle, the muscle width and median, skewness, and kurtosis of the intensity were compared with the Baker score. Univariate analysis (UVA) using a Wilcoxon rank-sum test and multivariate analysis with the least absolute shrinkage and selection operator logistic regression was performed to determine significant differences in these features between the patient groups categorized according to their Baker’s scores. Results UVA showed statistically significant differences between grade 1 and grade ≥2 for morphologic shape features and histogram features, except for volume and skewness. Only eccentricity, ratio length, and volume were borderline significant in differentiating grade ≤2 and grade ≥3. Features with P<.1 on UVA were used in the multivariate least absolute shrinkage and selection operator logistic regression analysis. Multivariate analysis showed a good level of predictive power for grade 1 versus grade ≥2 CC (area under the receiver operating characteristic curve 0.78, sensitivity 0.78, and specificity 0.82) and for grade ≤2 versus grade ≥3 CC (area under the receiver operating characteristic curve 0.75, sensitivity 0.75, and specificity 0.79). Conclusions The morphologic shape features described on MR images were associated with the severity of CC. MRI has the potential to further improve the diagnostic ability of the Baker score in breast cancer patients who undergo implant reconstruction.

3D images of the silicone implants in capsular contracture after breast augmentation using magnetic resonance imaging with SPACE sequence

“…found that the average thickness of capsules was about 2.39 mm in cases with Baker grade III or IV, whereas the average thickness was 1.14 mm in cases with Baker grade I or II 10 10 . In contrast to previous findings, no difference was found on MR images between low-grade and high-grade capsular contracture in the capsule thickness of another 50 patients 11 .…”

“…MRI and mammographic imaging can display implant deformation, however, ultrasonography is difficult to reflect the deformation because of the small field of view. Tyagi et al quantified the shape features of implants using MRI, such as roundness, eccentricity, and ratio length, which were associated with the severity of capsular contracture 11 . However, the complexity of calculating the parameters of shape features limited their application in daily clinical practice.…”

“…The imaging findings of the thickened capsule and the alteration of implant shape may be the indications of capsular contracture 9 . Several studies have revealed that MRI correlated well with the Baker grade system and effectively used to assess capsular contracture, by the evaluation of the thickness of capsule and shape features of implant [10][11][12] . The shape features, such as roundness, eccentricity, and ratio length for the implant, are so difficult to calculate, which limits their application in daily clinical practice.…”

Towards a consensus approach for assessing capsular contracture severity and progression: A systematic review

“…An association between MRI and Baker grade has also been studied in patients undergoing only implant-based postmastectomy breast reconstruction. 18 , 19 Following multiple regression analyses, Mori et al 18 failed to identify a statistically significant association between capsular thickness and Baker grade severity. Tyagi et al 19 corroborated these findings, also failing to identify differences in capsular thickness across Baker grades I to IV.…”

An experimental study on the prosthesis produced by inactivated autologous subcutaneous adipose tissue and skin dermal tissue in a mini-pig model

“…It will then form a layer of membranous structures to encapsulate the prosthesis, known as the prosthesis capsule. In a few patients, this layer of capsule will become thick, hard, or even produce a compression prosthesis deformation and pain symptoms, known as a “capsular contracture” ( 14 ). In serious cases, it even induces local tissue canceration ( 15 , 16 ).…”