Optical diagnostics of liver tumors using an autofluorescence lifetime probe

Liver cancer is a global health challenge and its incidence is expected to grow worldwide to 1 million new cases in 2025. While hepatocellular carcinoma (HCC) is the most common liver cancer, hepatic metastases of colorectal cancer (CRLM) occur in almost 50% of patients with CRC. For both HCC and CRLM, surgical resection represents the only chance of long-term survival. In this context, a label-free optical surgical guidance tool would be highly suitable for reducing the positive margin rate and improving patient outcomes. In this study, we used a fiber-based autofluorescence lifetime imaging probe to provide real-time discrimination of tumor from marginal tissues in freshly excised liver samples. The proposed method allowed discriminating tumors from healthy tissue by reporting the fluorescence lifetime decay of cellular metabolic biomarkers, i.e., NAD(P)H and FAD. The acquisitions on 37 surgical specimens of both HCC and CRLM demonstrate that this approach is a method for delineating tumor borders with 67.7% and 77% accuracy, respectively. The results, combined with the ability to capture and process images in real time under bright background, highlight the technology's potential for clinical use for both label-free tissue diagnostics and surgical guidance.