title: In Vivo Multiphoton Microscopy of Basal Cell Carcinoma.
abstract: OBJECTIVE
  Basal cell carcinomas (BCCs) are diagnosed by clinical evaluation, which can include dermoscopic evaluation, biopsy, and histopathologic examination. Recent translation of multiphoton microscopy (MPM) to clinical practice raises the possibility of noninvasive, label-free in vivo imaging of BCCs that could reduce the time from consultation to treatment.
  
  
  OBJECTIVE
  To demonstrate the capability of MPM to image in vivo BCC lesions in human skin, and to evaluate if histopathologic criteria can be identified in MPM images.
  
  
  METHODS
  Imaging in patients with BCC was performed at the University of California-Irvine Health Beckman Laser Institute & Medical Clinic, Irvine, between September 2012 and April 2014, with a clinical MPM-based tomograph. Ten BCC lesions were imaged in vivo in 9 patients prior to biopsy. The MPM images were compared with histopathologic findings.
  
  
  METHODS
  MPM imaging identified in vivo and noninvasively the main histopathologic feature of BCC lesions: nests of basaloid cells showing palisading in the peripheral cell layer at the dermoepidermal junction and/or in the dermis.
  
  
  RESULTS
  The main MPM feature associated with the BCC lesions involved nests of basaloid cells present in the papillary and reticular dermis. This feature correlated well with histopathologic examination. Other MPM features included elongated tumor cells in the epidermis aligned in 1 direction and parallel collagen and elastin bundles surrounding the tumors.
  
  
  CONCLUSIONS
  This study demonstrates, in a limited patient population, that noninvasive in vivo MPM imaging can provide label-free contrast that reveals several characteristic features of BCC lesions. Future studies are needed to validate the technique and correlate MPM performance with histopathologic examination.
authors.affiliation: Laser Microbeam and Medical Program, Beckman Laser Institute, University of California-Irvine, Irvine.
authors.forename: Mihaela
authors.initials: M
authors.lastname: Balu
authors.affiliation: Department of Dermatology, University of California-Irvine, Irvine.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Zachary
authors.affiliation: Department of Dermatology, University of California-Irvine, Irvine.
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Harris
authors.affiliation: Laser Microbeam and Medical Program, Beckman Laser Institute, University of California-Irvine, Irvine.
authors.forename: Tatiana B
authors.initials: TB
authors.lastname: Krasieva
authors.affiliation: JenLab GmbH, Jena, Germany4Department of Biophotonics and Laser Technology, Saarland University, Saarbrücken, Germany.
authors.forename: Karsten
authors.initials: K
authors.lastname: König
authors.affiliation: Laser Microbeam and Medical Program, Beckman Laser Institute, University of California-Irvine, Irvine.
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Tromberg
authors.affiliation: Department of Dermatology, University of California-Irvine, Irvine.
authors.forename: Kristen M
authors.initials: KM
authors.lastname: Kelly
mesh_terms: D001706:Biopsy; D002280:Basal Cell Carcinoma / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods*; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000473:pathology