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

Development and Validation of a Diagnostic Histopathological Scoring System for Capsular Contracture Based on 720 Breast Implant Capsules

BACKGROUND

Capsular contracture is traditionally evaluated with the Baker classification, but this has notable limitations regarding reproducibility and objectivity.

OBJECTIVES

The aim of this study was to develop and validate procedure-specific histopathological scoring systems to assess capsular contracture severity.

METHODS

Biopsies of breast implant capsules were used to develop histopathological scoring systems for patients following breast augmentation and breast reconstruction. Ten histological parameters were evaluated by multivariable logistic regression to identify those most associated with capsular contracture. Significant parameters (P < .05) were selected for the scoring systems and assigned weighted scores (1-10). Validation was assessed from the area under the curve (AUC) and the mean absolute error (MAE).

RESULTS

A total of 720 biopsies from 542 patients were included. Four parameters were selected for the augmentation scoring system, namely, collagen layer thickness, fiber organization, inflammatory infiltration, and calcification, providing a combined maximum score of 26. The AUC and MAE for the augmentation scoring system were 81% and 0.8%, which is considered strong. Three parameters were selected for the reconstruction scoring system, namely, fiber organization, collagen layer cellularity, and inflammatory infiltration, providing a combined maximum score of 19. The AUC and MAE of the reconstruction scoring system were 72% and 7.1%, which is considered good.

CONCLUSIONS

The new histopathological scoring systems provide an objective, reproducible, and accurate assessment of capsular contracture severity. We propose these novel scoring systems as a valuable tool for confirming capsular contracture diagnosis in the clinical setting, for research, and for implant manufacturers and insurance providers in need of a confirmed capsular contracture diagnosis.

LEVEL OF EVIDENCE: 3

A Phase II Study Evaluating the Effect of Intensity Modulated Postmastectomy Radiation Therapy on Implant Failure Rates in Breast Cancer Patients With Immediate, 2-Stage Implant Reconstruction With an MRI Imaging Correlative Substudy

PURPOSE

Postmastectomy radiation therapy is a mainstay in the adjuvant treatment of node-positive breast cancer, but it poses risks for women with breast reconstruction. Multibeam intensity-modulated radiation therapy improves dose conformality and homogeneity, potentially reducing complications in breast cancer patients with implant-based reconstruction. To investigate this hypothesis, we conducted a single-arm phase 2 clinical trial of breast cancer patients who underwent mastectomy/axillary dissection and prosthesis-based reconstruction.

METHODS AND MATERIALS

The primary endpoint was the rate of implant failure (IF) within 24 months of permanent implant placement, which would be considered an improvement over historical controls if below 16%. IF was defined as removal leading to a flat chest wall or replacement with another reconstruction. Patients were analyzed in 2 cohorts. Cohort 1 (RT-PI) received radiation therapy to the permanent implant. Cohort 2 (RT-TE) received radiation therapy to the TE. IF rates, adverse events, and quality of life were analyzed. Follow-up/postradiation therapy assessments were compared with the baseline/preradiation therapy assessments at 3 to 10 weeks after exchange surgery. A subgroup underwent serial magnetic resonance imaging (MRI) sessions to explore the association between MRI-detected changes and capsular contracture, a known adverse effect of radiation therapy.

RESULTS

Between June 2014 and March 2017, 119 women were enrolled. Cohort 1 included 45 patients, and cohort 2 had 74 patients. Among 100 evaluable participants, 25 experienced IF during the study period. IF occurred in 8/42 (19%) and 17/58 (29%) in cohorts 1 and 2, respectively. Among the IFs, the majority were due to capsular contracture (13), infection (7), exposure (3), and other reasons (2). Morphologic shape features observed in longitudinal MRI images were associated with the development of Baker grade 3 to 4 contractures.

CONCLUSIONS

The rate of IF in reconstructed breast cancer patients treated with intensity-modulated radiation therapy was similar to, but not improved over, that observed with conventional, 3-dimensional-conformal methods. MRI features show promise for predicting capsular contracture but require validation in larger studies.

Toward a Consensus Aproach for Assessing Capsular Contracture Severity and Progression: A Systematic Review

BACKGROUND

Breast implants are the most commonly used medical devices in plastic surgery, and capsular contracture (CC) is one of the most common complications. However, our assessment of CC is based largely on Baker grade, which is problematically subjective and affords only four possible values.

METHODS

The authors performed a systematic review concluding in September of 2021 in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. It identified 19 articles that propose approaches to measuring CC.

RESULTS

In addition to Baker grade, the authors identified several modalities reported to measure CC. These included magnetic resonance imaging, ultrasonography, sonoelastography, mammacompliance measuring devices, applanation tonometry, histologic evaluation, and serology. Capsule thickness and other measures of CC inconsistently correlated with Baker grade, whereas the presence of synovial metaplasia was consistently associated with Baker grade I and II, but not III and IV capsules.

CONCLUSIONS

There remains no particular method to reliably and specifically measure the contracture of capsules that form around breast implants. As such, we would recommend that research investigators use more than one modality to measure CC. Other variables that can impact breast implant stiffness and associated discomfort beyond CC need to be considered when evaluating patient outcomes. Given the value placed on CC outcomes in assessing breast implant safety, and the prevalence of breast implants overall, the need for a more reliable approach to measuring this outcome persists.

Ultrasound Criteria and Baker Scale for Breast Implant Capsular Contracture Diagnosis

Due to the subjectivity of the Baker scale in grading capsular contracture (CC), an objective and reproducible measurement tool is necessary to estimate the presence and grade of CC in patients with breast implants. This study aimed to assess the capacity of breast ultrasonography to identify CCs using the Baker grading system.

Methods

This study included patients who underwent breast augmentation with implants or implant-based breast reconstruction. Patient demographics, surgical type, and ultrasonographic variables were analyzed. The Kruskal-Wallis test was used to determine differences between means, and the Fisher exact test was used for binary variables.

Results

A total of 21 patients (28 breasts) with smooth surface implants were included. In total, 39.2% of breasts had a score of Baker I, 25% had Baker II, 17.9% had Baker III, and 17.9% had Baker IV. When comparing breasts graded Baker I to IV, a mean capsule thickness of 0.6 ± 0.2, 1.0 ± 0.53, 1.68 ± 0.99, and 1.52 ± 0.46 mm, respectively, was shown (P = 0.0044). The breast implant deformity variable was significantly different between Baker grades I to IV (0.0218). Finally, Baker III and IV categories were five times more likely to have abnormal wrinkles than Baker I and II (odds ratio, 5.25; 95% confidence interval, 0.82-33.45; P = 0.0496).

Conclusion

Ultrasound is a useful tool for evaluating the presence of augmented thickness, implant shape deformity, and abnormal wrinkles of the implant shell in correlation with the severity of CC.

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

BACKGROUND

Capsular contracture is a common complication after breast augmentation. However, no objective methods are available to assess capsular contracture at present. The goal of the present study was to evaluate the correlation between capsular contracture and 3D images of the silicone implants by using magnetic resonance imaging (MRI) with sampling perfection with application optimized contrast using different flip angle evolutions (SPACE) sequence.

METHODS

Twenty-one patients (42 breasts) underwent breast augmentation, had postoperative MRI examinations with SPACE sequence, and the evaluation of the Baker grade by two trained plastic surgeons. Capsular thickness was measured on the T2-weighted images. The software ITK-SNAP was used to reconstruct 3D images of the implants. The fold characteristics such as number, depth, direction, and distribution were compared with the Baker grade.

RESULTS

Of the 42 breasts, 14, 8, 12, and 8 breasts were classified as Baker grade I, II, III, and IV, respectively. The MRI images of breasts with Baker grade III or IV revealed a thicker capsule (mean of 2.29 mm) as compared to the capsule with the lower Baker grades (mean of 1.58 mm). The 3D images of implants showed no difference in the number of folds between the groups with different Baker grades. The fold direction and fold distribution differed between grade I to II and grade III to IV.

CONCLUSION

The 3D image of an implant with pathological folds is a potential and feasible diagnostic indication of capsular contracture.

LEVEL OF EVIDENCE

IV.