Volumetric breast density is essential for predicting cosmetic outcome at the late stage after breast-conserving surgery.

ABSTRACT

BACKGROUND: The critical issue related to breast-conserving therapy (BCT) is that cosmetic outcomes deteriorate with long-term follow-up. There is little research for breast density as a predictor of cosmetic outcomes at the late stage after BCT. To improve the long-term quality of life after BCT of breast cancer patients, the correlation of volumetric breast density (VBD) and cosmetic outcome at the late stage after BCT was evaluated. STUDY DESIGN: Breast volume, fibroglandular tissue volume, adipose tissue volume, and VBD were calculated on mammography using image analysis software (Volpara(®)) in 151 patients with BCT. Furthermore, the correlation of breast density and the change of breast volume over time was analyzed on mammography in 99 patients who were followed-up long-term after BCT. RESULTS: On multivariate analysis, VBD was a predictor of cosmetic outcome after BCT with percent breast volume excised (PBVE). Decreased adipose tissue volume and increased fibrosis were more common in patients with VBD < 15%. Furthermore, remnant breast volume continued to decrease over time in low breast density patients during long-term follow-up. 93% of patients with VBD ≥ 15% and PBVE < 10% had a better cosmetic outcome, while 60% of patients with VBD < 15% and PBVE ≥ 10% had a worse cosmetic outcome after BCT. CONCLUSIONS: While PBVE was involved in cosmetic outcome at the early stage after BCT, VBD was associated with cosmetic outcome at the late stage after BCT. Thus, a combination of VBD and PBVE could predict cosmetic outcome after BCT and contribute to the selection for the appropriate BCT.