Quantitative 3D Photographic Assessment of Breast Cosmesis after Whole Breast Irradiation for Early-Stage Breast Cancer: A Secondary Analysis of a Randomized Clinical Trial

Abstract Purpose To use 3D surface photography to quantitatively measure breast cosmesis within the framework of a randomized clinical trial of conventionally fractionated (CF) and hypofractionated (HF) whole breast irradiation (WBI), to identify how 3D measurements are associated with patient- and physician-reported cosmesis, and to determine whether objective measures of breast symmetry varied by WBI treatment arm or TGFB1 status. Methods From 2011-2014, 287 women age ≥40 with ductal carcinoma in situ or early-stage invasive breast cancer were enrolled in a multicenter trial and randomized to HF-WBI or CF-WBI with a boost. Three-dimensional surface photography was performed at 3 years post-treatment. Patient-reported cosmetic outcomes were recorded with the Breast Cancer Treatment Outcome Scale. Physician-reported cosmetic outcomes were assessed by the Radiation Therapy Oncology Group scale. Volume ratios and six quantitative measures of breast symmetry, termed F1-6C, were calculated using the breast contour and fiducial points assessed on 3D surface images. Associations between all metrics, patient- and physician-reported cosmesis, treatment arm, and TGFB1 genotype were performed using the Kruskal-Wallis test and multivariable logistic regression models. Results Among 77 (39 CF-WBI and 38 HF-WBI) evaluable patients, both patient- and physician-reported cosmetic outcomes were significantly associated with the F1C vertical symmetry measure (both P Conclusions Quantitative 3D image-derived measures reveal comparable cosmetic outcomes with HF-WBI as compared to CF-WBI. Our findings suggest that 3D surface imaging may be a more sensitive method for measuring subtle cosmetic changes than global patient- or physician-reported assessments.