Case Report: A 3D-Printed Surgical Guide for Breast-Conserving Surgery After Neoadjuvant Chemotherapy.

BACKGROUND: A challenging problem for patients undergoing breast-conserving surgery after neoadjuvant chemotherapy (NACT) is the accuracy of preoperative tumor localization. After chemotherapy, the original tumor is likely to shrink or scatter dramatically or even show complete remission. For breast-conserving surgery, the development of a guidance device to accurately estimate the resection area is imperative. CASE PRESENTATION: We produced a three-dimensional (3D)-printed breast surgical guide (BSG) based on prone and supine magnetic resonance imaging (MRI). This device was tested on a patient who underwent breast-conserving surgery after NACT. Both ultrasonography and MRI revealed that the tumor shrank substantially after NACT. Identifying the target tumor area using pre-NACT MRI was feasible, and the tumor was safely removed with clear resection margins. CONCLUSION: The BSG has several advantages over conventional methods for tumor localization after NACT. In particular, the BSG provided precise quantitative MRI information about the tumor area.