Efficacy of Contrast-Enhanced Cone-Beam Breast CT in Assessing NAC Involvement

Overview

This study evaluated the diagnostic performance of contrast-enhanced cone-beam breast CT (CE-CBBCT) for preoperative assessment of nipple–areolar complex (NAC) involvement in early breast cancer. Using propensity score-matched cases, CE-CBBCT demonstrated promising accuracy in identifying NAC involvement, potentially aiding surgical decision-making for nipple-sparing mastectomy.

Background

Nipple-sparing mastectomy (NSM) preserves the nipple–areola complex (NAC) and skin while removing breast glandular tissue, addressing patients' psychological needs. However, NAC involvement occurs in 8% to 27.7% of breast cancer cases and is a contraindication for NSM. Accurate preoperative evaluation of NAC involvement is essential. Conventional imaging modalities such as mammography, ultrasound, MRI, and PET/CT have shown variable accuracy (80.8%–87.4%) and sensitivity (60.5%–92%) in predicting NAC involvement. CE-CBBCT is a novel imaging technique offering rapid, non-compressive, high-resolution 3D breast imaging with contrast enhancement, but its role in assessing NAC involvement remains underexplored.

Data Highlights

A retrospective study included 182 breast cancer cases (91 with pathological NAC involvement and 91 matched controls without NAC involvement) from a cohort of 641 cases. CE-CBBCT imaging was performed with two-phase contrast-enhanced scans. Imaging features assessed included asymmetric NAC enhancement, nipple retraction, periareolar skin thickening, suspicious calcifications, and tumor–nipple distance. Radiologists independently evaluated imaging blinded to pathology results.

Key Findings

• CE-CBBCT demonstrated high diagnostic accuracy in detecting NAC involvement in early breast cancer.
• Significant imaging predictors of NAC involvement included asymmetric NAC enhancement and nipple retraction on CE-CBBCT.
• CE-CBBCT allows simultaneous assessment of microcalcifications and contrast enhancement without breast compression.
• Propensity score matching controlled for confounders such as age, menopausal status, and tumor stage, strengthening the validity of findings.
• CE-CBBCT may provide a non-invasive, rapid, and reliable imaging modality to guide surgical planning for NSM candidates.

Clinical Implications

CE-CBBCT can be integrated into preoperative breast cancer evaluation to improve detection of NAC involvement, thereby aiding in selecting appropriate candidates for nipple-sparing mastectomy. Its ability to provide detailed 3D imaging without compression and to assess both enhancement and calcifications may enhance diagnostic confidence. Clinicians should consider CE-CBBCT especially in patients contraindicated for MRI or when detailed NAC assessment is required.

Conclusion

Contrast-enhanced cone-beam breast CT shows promising diagnostic performance in assessing nipple–areolar complex involvement in early breast cancer, supporting its use as a valuable tool in preoperative evaluation and surgical planning.

References

1. Sun Yat-sen University Cancer Center Study 2019-2021 -- Efficacy of CE-CBBCT in NAC involvement
2. Regulatory Approvals -- CE-CBBCT by Chinese NMPA, US FDA, EU