Abstract PO3-22-10: 3D-CT mapping with a photo-translucent application using iPad delineates tumor lesions on patient breast skin in breast-conserving surgery: Preliminary results

Abstract

Abstract Objective: The aim of this study was to evaluate the feasibility and efficacy of a 3D-CT mapping technique with a photo-translucent application using an iPad for tumor localization on the patient's breast skin in breast-conserving surgery (BCS). We also compared the accuracy of tumor localization between conventional methods and 3D-CT mapping. Methods: Between February and July 2023, 20 female patients with early-stage (0 to 2) breast cancer scheduled for BCS were enrolled in this study. Preoperative enhanced CT scans were performed, and a 3D-CT image was generated by incorporating the patient's skin and manually marking the contrast-enhanced lesion using SYNAPSE VINCENT software. The 3D-CT images, adjusted to individual rotation angles to match the horizontal skin position above the tumor, were imported into an iPad equipped with a photo-translucent application. Using a securely fixed iPad holder, the translucent image was superimposed on the patient's breast, and the enhanced lesion was marked on the skin using a blue pen. Conventional tumor marking was performed based on ultrasound imaging, CT, and MRI findings using a black pen. Photographs were taken to simulate BCS based on the 3D-CT blue marking. All patients underwent BCS with resection margins of 1.5-2 cm from the black marking, and intraoperative frozen section analysis was performed to assess the resection margins. Results: The majority of patients had hormone receptor-positive breast cancers, and neoadjuvant chemotherapy was administered in three patients (Table 1). The extent of tumor involvement assessed by pathological assessment and imaging findings showed the least discrepancy with MRI, with an average error of 4.2 mm. MRI also had the lowest rate of missed tumor detection compared to other imaging modalities. The initial positive margin rate was 20%, and the simulation conducted in this study did not alter that value. Furthermore, the simulation demonstrated more effective excision of the tumor's center compared to conventional surgical methods (Table 2). Conclusion: The use of 3D-CT mapping with a photo-translucent application on an iPad offers a promising approach for accurate tumor localization in BCS. This technique provides a simplified and efficient method, and it can also be applied to cases where lesions have completely disappeared after neoadjuvant chemotherapy. XX- XX XX- XX Citation Format: Gou Watanabe, Akihiko Suzuki. 3D-CT mapping with a photo-translucent application using iPad delineates tumor lesions on patient breast skin in breast-conserving surgery: Preliminary results [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-22-10.