Abstract: Objective To investigate the application value of cone-beam breast computed tomography (CBBCT) in prosthetic breast reconstruction after nipple-sparing mastectomy (NSM). Methods A total of 52 breast cancer patients who received prosthetic breast reconstruction after NSM at Guangxi Medical University Cancer Hospital from July 1, 2020 to January 31, 2022 were selected as the subjects. Spearman rank correlation was used to analyze the correlation between the measured volumes of the affected breast CBBCT and the contralateral breast CBBCT and the implanted prosthesis volume obtained by the clinical manual linear measurement method. A simple linear regression equation was established to predict the prosthesis volume calculated by CBBCT, and to compare it with the volume of implanted prosthesis. The Harris beauty score was used to evaluate the cosmetic effect 3 months after surgery. Results All patients completed breast prosthesis reconstruction without prosthesis rupture, prosthesis displacement and other complications. The measured volumes of the affected breast CBBCT and the contralateral breast CBBCT were correlated with the implanted prosthesis volume (r_s=0.73, 0.81). A linear prediction model y=0.001x+4.897 (R²=0.7, P<0.001) was constructed based on the measured volume of the contralateral breast CBBCT. The clinical validation showed that there was no significant difference between the model predicted volume and the implanted volume of prosthesis (t=0.03, P=0.98), and the mean absolute error value was only 0.1 cm³. The Harris beauty score showed that the cosmetic effect was excellent in 4 cases and good in 6 cases 3 months after operation. Conclusions CBBCT can effectively predict the volume of implanted prosthesis in breast reconstruction surgery after NSM.

Key words: Breast cancer, NSM, Prosthetic breast reconstruction, CBBCT, Breast volume, Prosthesis measurement