Comparison of Mammographic Findings after Conventional Radiotherapy and forward Intensity-Modulated Radiation Therapy in Breast Conservative Therapy.

ABSTRACT

OBJECTIVE: This study aimed to determine and compare mammographic findings after conventional radiotherapy and forward intensity-modulated radiation therapy for breast conservation. METHODS: Eighty-six patients with BCT (373 mammograms) were included between 2010-2015 and had post-treatment mammograms available for review. All mammograms were taken with an 18 × 24 cm detector and 0.070 mm pixel size (Selenia Dimensions, Hologic, Marlborough, Massachusetts, US). We documented the radiation technique, dose, and mammographic findings (e.g., edema, thickening, scarring, and calcification). We tracked the stability duration for each patient and grouped mammographic findings into 1-, 2, and 3 years post-treatment. SPSS version 26 and Stata version 18 were used for analysis. RESULTS: The FIMRT group received a lower total radiation dose (p=0.030), a higher dose per fraction (p=0.030), and a lower maximum skin dose (p<0.001). The time to stable was shorter in the FIMRT group (975 days for CRT vs. 478 days for FIMRT; p=0.001). Among the 86 patients, the FIMRT group showed less breast parenchymal edema and noticeable scarring at 1, 2, and 3 years post-treatment than the CRT group, although the difference was not statistically significant. CONCLUSION: In the FIMRT group, post-BCT mammographic findings, including breast parenchymal edema and marked scar appearance, were fewer than those in the CRT group, and the duration to stable was significantly reduced.