Interventional real-time optical imaging guidance for complete tumor ablation
Menée in vitro, ex vivo et à l'aide d'un modèle animal de tumeur hépatique Vx2, cette étude met en évidence l'intérêt d'une technique de guidage en temps réel utilisant l'imagerie optique pour réaliser l'ablation complète d'une tumeur
We present an interventional optical imaging–guided oncologic technique. This interventional oncologic technique can differentiate, in vivo, the three definitive zones of tumor and tumor margin as well as normal surrounding liver, which enables differentiation of residual viable tumors from ablated nonviable tumors and thereby pretermit the intraprocedural real-time guidance for complete tumor eradication during a single interventional ablation session. This innovation should revolutionize the current ablation technology, leading to a significant advancement in the complete treatment of larger or irregular malignant lesions not only in the liver but also in other solid organs.The aim of this study was to develop an interventional optical imaging (OI) technique for intraprocedural guidance of complete tumor ablation. Our study employed four strategies: 1) optimizing experimental protocol of various indocyanine green (ICG) concentrations/detection time windows for ICG-based OI of tumor cells (ICG cells); 2) using the optimized OI to evaluate ablation-heat effect on ICG cells; 3) building the interventional OI system and investigating its sensitivity for differentiating residual viable tumors from nonviable tumors; and 4) preclinically validating its technical feasibility for intraprocedural monitoring of radiofrequency ablations (RFAs) using animal models with orthotopic hepatic tumors. OI signal-to-background ratios (SBRs) among preablation tumors, residual, and ablated tumors were statistically compared and confirmed by subsequent pathology. The optimal dose and detection time window for ICG-based OI were 100 μg/mL at 24 h. Interventional OI displayed significantly higher fluorescence signals of viable ICG cells compared with nonviable ICG cells (189.3 ± 7.6 versus 63.7 ± 5.7 au, P < 0.001). The interventional OI could differentiate three definitive zones of tumor, tumor margin, and normal surrounding liver, demonstrating significantly higher average SBR of residual viable tumors compared to ablated nonviable tumors (2.54 ± 0.31 versus 0.57 ± 0.05, P < 0.001). The innovative interventional OI technique permitted operators to instantly detect residual tumors and thereby guide repeated RFAs, ensuring complete tumor eradication, which was confirmed by ex vivo OI and pathology. In conclusion, we present an interventional oncologic technique, which should revolutionize the current ablation technology, leading to a significant advancement in complete treatment of larger or irregular malignancies.All data used for the study are within the manuscript and SI Appendix.