Fluorescence grid analysis for the evaluation of piecemeal surgery in sinonasal inverted papilloma: a proof-of-concept study

Detection of Tumour-Targeted IRDye800CW Tracer with Commercially Available Laparoscopic Surgical Systems

(1) Introduction: Near-infrared fluorescence (NIRF) combined with tumour-targeted tracers, such as bevacizumab-800CW, could aid surgical decision-making. This study explored the use of IRDye800CW, conjugated to bevacizumab, with four commercially available NIRF laparoscopes optimised for indocyanine green (ICG). (2) Methods: A (lymph node) phantom was made from a calibration device for NIRF and tissue-mimicking material. Serial dilutions of bevacizumab-800CW were made and ICG functioned as a reference. System settings, working distance, and thickness of tissue-mimicking material were varied to assess visibility of the fluorescence signal and tissue penetration. Tests were performed with four laparoscopes: VISERA ELITE II, Olympus; IMAGE1 S™ 4U Rubina, KARL STORZ; ENDOCAM Logic 4K platform, Richard Wolf; da Vinci Xi, Intuitive Surgical. (3) Results: The lowest visible bevacizumab-800CW concentration ranged between 13-850 nM (8-512 times diluted stock solution) for all laparoscopes, but the tracer was not visible through 0.8 cm of tissue in all systems. In contrast, ICG was still visible at a concentration of 0.4 nM (16,384 times diluted) and through 1.6-2.4 cm of tissue. Visibility and tissue penetration generally improved with a reduced working distance and manually adjusted system settings. (4) Conclusion: Depending on the application, bevacizumab-800CW might be sufficiently visible with current laparoscopes, but optimisation would widen applicability of tumour-targeted IRDye800CW tracers.

New and effective EGFR-targeted fluorescence imaging technology for intraoperative rapid determination of lung cancer in freshly isolated tissue

PURPOSE

During lung cancer surgery, it is very important to define tumor boundaries and determine the surgical margin distance. In previous research, systemically application of fluorescent probes can help medical professionals determine the boundaries of tumors and find small tumors and metastases, thereby improving the accuracy of surgical resection. However, there are very few safe and effective probes that can be applied to clinical trials up to now, which limits the clinical application of fluorescence imaging. Here we developed a new technology that can quickly identify the tumor area in the resected lung tissue during the operation and distinguish the tumor boundary and metastatic lymph nodes.

EXPERIMENTAL DESIGN

For animal studies, a PDX model of lung cancer was established. The tumors, lungs, and peritumoral muscle tissues of tumor-bearing mice were surgically removed and incubated with a probe targeting epidermal growth factor receptor (EGFR) for 20 min, and then imaged by a closed-field near-infrared two-zone (NIR-II) fluorescence imaging system. For clinical samples, ten surgically removed lung tissues and 60 lymph nodes from 10 lung cancer patients undergoing radical resection were incubated with the targeting probe immediately after intraoperative resection and imaged to identify the tumor area and distinguish the tumor boundary and metastatic lymph nodes. The accuracy of fluorescence imaging was confirmed by HE staining and immunohistochemistry.

RESULTS

The ex vivo animal imaging experiments showed a fluorescence enhancement of tumor tissue. For clinical samples, our results showed that this new technology yielded more than 85.7% sensitivity and 100% specificity in identifying the tumor area in the resected lung tissue. The average fluorescence tumor-to-background ratio was 2.5 ± 1.3. Furthermore, we also used this technique to image metastatic lymph nodes intraoperatively and showed that metastatic lymph nodes have brighter fluorescence than normal lymph nodes, as the average fluorescence tumor-to-background signal ratio was 2.7 ± 1.1. Calculations on the results of the fluorescence signal in relation to the number of metastatic lymph nodes yielded values of 77.8% for sensitivity and 92.1% for specificity. We expect this new technology to be a useful diagnostic tool for rapid intraoperative pathological detection and margin determination.

CONCLUSIONS

By using fluorescently labeled anti-human EGFR recombinant antibody scFv fragment to incubate freshly isolated tissues during surgery, the probes can quickly accumulate in lung cancer tissues, which can be used to quickly identify tumor areas in the resected lung tissues and distinguish tumor boundaries and find metastases in lymph nodes. This technology is expected to be used for rapid intraoperative pathological detection and margin determination.

Image-guided surgery and novel intraoperative devices for enhanced visualisation in general and paediatric surgery: a review

Fluorescence guided surgery, augmented reality, and intra-operative imaging devices are rapidly pervading the field of surgical interventions, equipping the surgeon with powerful tools capable of enhancing the surgical visualisation of anatomical normal and pathological structures. There is a wide range of possibilities in the adult population to use these novel technologies and devices in the guidance for surgical procedures and minimally invasive surgeries. Their applications and their use have also been increasingly growing in the field of paediatric surgery, where the detailed visualisation of small anatomical structures could reduce procedure time, minimising surgical complications and ultimately improve the outcome of surgery. This review aims to illustrate the mechanisms underlying these innovations and their main applications in the clinical setting.