Application research of pulmonary nodule localization techniques in video-assisted thoracic surgery

Objective To evaluate the value and challenges of CT-guided percutaneous placement of coil and indocyanine green (ICG) in the pulmonary nodule localization techniques in video-assisted thoracic surgery (VATS). Additionally, to explore a new fluorescent probe targeting lung cancers. Methods This study analyzed 26 patients underwent CT-guided coil placement at the edges of pulmonary nodules and received ICG injection. Intraoperative fluorescence imaging was conducted using a fluorescence thoracoscope to assist in lesion localization and resection. Given the challenges observed in clinical cases, the study designed a new molecular imaging probe, NY-FR-07 targeting folate receptor alpha (FR-α) of lung cancer. Cellular and animal experiments were conducted to validate its safety, targeting ability of FR-α, and in vivo imaging efficacy of tumors. Results In the VATS guided by the coils and ICG, all 26 lesions were successfully resected. However, coil displacement and ICG diffusion into the thoracic cavity occurred, leading to an expanded surgical field in nine of the cases. To overcome these challenges, a novel fluorescent probe named NY-FR-07 was successfully developed, characterized by minimal cytotoxicity and good biocompatibility. Animal experiments demonstrated that the tumor fluorescence intensity of NY-FR-07 is higher than that of lung tissue at 24 h and 72 h. In the 0.03 mg/kg dose group at 24 h, the tumor-to-lung ratio is 1.714. At 72 h, the tumor-to-lung ratio in all different dose groups exceeds 1.5. Conclusion The coil and ICG localization can assist the VATS of pulmonary nodules, but it still has some limitations. Additionally, the new FR-α targeted fluorescent probe NY-FR-07 demonstrates excellent biocompatibility and precise targeting capabilities, showing potential in accurately identifying the position and boundaries of lung cancer during VATS.