Multimodal fiber-probe spectroscopy for the diagnostics and classification of bladder tumors
Authors: Anand S., Cicchi R., Fantechi R., Gacci M., Nesi G., Carini M., Pavone F.S.
Autors Affiliation: National Institute of Optics, National Research Council (INO-CNR), Via Nello Carrara 1, Sesto Fiorentino, 50019, Italy; European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Via Nello Carrara 1, Sesto Fiorentino, 50019, Italy; Division of Urology, Department of Surgical and Medical Critical Area, University of Florence, Florence, I-50100, Italy; Division of Pathology, Department of Surgical and Medical Critical Area, University of Florence, Florence, I-50100, Italy; Department of Physics, University of Florence, Via Giovanni Sansone 1, Sesto Fiorentino, 50019, Italy
Abstract: The gold standard for the detection of bladder cancer is white light cystoscopy, followed by an invasive biopsy and pathological examination. Tissue pathology is time consuming and often prone to sampling errors. Recently, optical spectroscopy techniques have evolved as promising techniques for the detection of neoplasia. The specific goal of this study is to evaluate the application of combined auto-fluorescence (excited using 378 nm and 445 nm wavelengths) and diffuse reflectance spectroscopy to discriminate normal bladder tissue from tumor at different grades. The fluorescence spectrum at both excitation wavelengths showed an increased spectral intensity in tumors with respect to normal tissues. Reflectance data indicated an increased reflectance in the wavelength range 610 nm-700 nm for different grades of tumors, compared to normal tissues. The spectral data were further analyzed using principal component analysis for evaluating the sensitivity and specificity for diagnosing tumor. The spectral differences observed between various grades of tumors provides a strong genesis for the future evaluation on a larger patient population to achieve statistical significance. This study indicates that a combined spectroscopic strategy, incorporating fluorescence and reflectance spectroscopy, could improve the capability for diagnosing bladder tumor as well as for differentiating tumors in different grades.
More Information: The research leading to these results has received funding from Fondazione Pisa in the framework of the project “Diagnostic technology for the post-operative monitoring of pediatric brain tumors”, from the Italian Ministry for Education, University and Research in the framework of the Flagship Project NANOMAX, from the European Union Seventh Framework Programme (FP7/20072013) under grant agreement number 284464, from the Italian Ministry of Health (GR-2011-02349626), from Tuscany Region and EU FP7 BiophotonicsPlus projects LighTPatcH (Led Technology in Photo Haemostasis) and LITE (Laser Imaging of The Eye), and from Ente Cassa di Risparmio di Firenze. Authors would like to thank the support staff in the surgery room from The University Hospital, Careggi for sample collection.KeyWords: Fluorescence; Histology; Population statistics; Principal component analysis; Reflection; Robotics; Spectroscopy; Spectrum analysis; Tissue; Tumors; Urology, Bladder tumor; Diffuse reflectance; Diffuse reflectance spectroscopy; Excitation wavelength; Optical spectroscopy techniques; Reflectance spectroscopy; Sensitivity and specificity; Statistical significance, Diagnosis