In situ detection of renal cell carcinomas using diffuse reflectance and fluorescence spectroscopy for enhanced biopsy guidance: An ex vivo study

Renal tumor biopsy is essential for diagnosing and treating renal cell carcinomas (RCC). However, due to sampling errors or missing the lesion during biopsy, multiple biopsies are often necessary to ensure accuracy. In this study, we investigated the potential of a miniaturized dual-modality spectroscopic probe, which integrates diffuse reflectance spectroscopy (DRS) and fluorescence spectroscopy (FS), for distinguishing renal tumors from normal tissue in situ. This probe has a slender outer diameter of 1.0 mm, allowing it to fit comfortably within a biopsy needle and reach renal tissue. DRS and FS data were collected from 237 locations in 30 fresh renal specimens, including both normal and RCC tissues, obtained from 30 renal surgery patients. The results were then compared with co-registered clinical standard histopathology. Notably, the median reflectance intensity in clear-cell RCC (ccRCC) tissues was significantly higher compared to normal renal tissues. Both Adaboost and VGG-19 classifiers were then employed to distinguish ccRCC from normal tissue. Our method could achieve over 93 % sensitivity and specificity with the Adaboost classifier on dual-modality spectrum data. Our results indicate that dual-modality spectroscopy holds promising potential as a label-free, real-time, in vivo renal tumor guidance tool during biopsy or radiofrequency ablation procedures, ultimately improving treatment outcomes.