title: A new generation of optical diagnostics for bladder cancer: technology, diagnostic accuracy, and future applications.
abstract: BACKGROUND
  New developments in optical diagnostics have a potential for less invasive and improved detection of bladder cancer.
  
  
  OBJECTIVE
  To provide an overview of the technology and diagnostic yield of recently developed optical diagnostics for bladder cancer and to outline their potential future applications.
  
  
  METHODS
  A PubMed literature search was performed, and papers on Raman spectroscopy (RS), optical coherence tomography (OCT), photodynamic diagnosis (PDD) and narrow-band imaging (NBI) regarding bladder cancer were reviewed. Technology, clinical evidence, and future applications of the techniques are discussed.
  
  
  RESULTS
  With RS, the molecular components of tissue can be measured objectively in qualitative and quantitative ways. The first studies demonstrating human in vivo applicability are still awaited. OCT produces high-resolution, cross-sectional images of tissue, comparable with histopathology, and provides information about depth of tumour growth. The first in vivo studies of OCT demonstrated promising diagnostic accuracy. RS and OCT are not suitable for scanning the entire bladder. PDD is a technique using fluorescence to indicate pathologic tissue. Several studies have shown that PDD increases the detection rate of bladder tumours and improves resection, resulting in fewer early recurrences. The relatively low specificity of PDD remains a problem. NBI enhances contrast of mucosal surface and microvascular structures. The NBI technique has clear advantages over PDD, and the two studies published to date have shown promising preliminary results. PDD and NBI do not contribute to histopathologic diagnosis.
  
  
  CONCLUSIONS
  RS and OCT aim at providing a real-time, minimally invasive, objective prediction of histopathologic diagnosis, while PDD and NBI aim at improving visualisation of bladder tumours. For RS, OCT, and NBI, more research has to be conducted before these techniques can be implemented in the management of bladder cancer. All techniques might be of value in specific clinical scenarios.
authors.affiliation: Department of Urology, Academic Medical Center Amsterdam, Amsterdam, The Netherlands. e.c.cauberg@amc.uva.nl
authors.forename: Evelyne C C
authors.initials: EC
authors.lastname: Cauberg
authors.forename: Daniël M
authors.initials: DM
authors.lastname: de Bruin
authors.forename: Dirk J
authors.initials: DJ
authors.lastname: Faber
authors.forename: Ton G
authors.initials: TG
authors.lastname: van Leeuwen
authors.forename: Jean J M C H
authors.initials: JJ
authors.lastname: de la Rosette
authors.forename: Theo M
authors.initials: TM
authors.lastname: de Reijke
mesh_terms: D002278:Carcinoma in Situ / Q000175:diagnosis*; D003950:Diagnostic Techniques, Urological / Q000639:trends; D005544:Forecasting; D006801:Humans; D015203:Reproducibility of Results; D013059:Spectrum Analysis, Raman; D041623:Tomography, Optical Coherence; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis*