title: Rapid visualization of nonmelanoma skin cancer.
abstract: BACKGROUND
  Mohs micrographic surgery examines all margins of the resected sample and has a 99% cure rate. However, many nonmelanoma skin cancers (NMSCs) are not readily amenable to Mohs micrographic surgery. This defines an unmet clinical need to assess the completeness of non-Mohs micrographic surgery resections during surgery to prevent re-excision/recurrence.
  
  
  OBJECTIVE
  We sought to examine the utility of quenched activity-based probe imaging to discriminate cancerous versus normal-appearing skin tissue.
  
  
  METHODS
  The quenched activity-based probe GB119 was applied to NMSC excised from 68 patients. We validated activation of the probe for hematoxylin-eosin-confirmed cancerous tissue versus normal-appearing skin tissue.
  
  
  RESULTS
  Topical application of the probe differentiated basal cell carcinoma and squamous cell carcinoma from normal-appearing skin with overall estimated sensitivity and specificity of 0.989 (95% confidence interval 0.940-1.00) and 0.894 (95% confidence interval 0.769-0.965), respectively. Probe activation accurately defined peripheral margins of NMSC as compared with conventional hematoxylin-eosin-based pathology.
  
  
  CONCLUSIONS
  This study only examined NMSC debulking excision specimens. The sensitivity and specificity for this approach using final NMSC excision margins will be clinically important.
  
  
  CONCLUSIONS
  These findings merit further studies to determine whether quenched activity-based probe technology may enable cost-effective increased cure rates for patients with NMSC by reducing re-excision and recurrence rates with a rapid and easily interpretable technological advance.
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Ethan
authors.initials: E
authors.lastname: Walker
authors.affiliation: Department of Dermatology, University Hospital, Cleveland, Ohio.
authors.forename: Margaret
authors.initials: M
authors.lastname: Mann
authors.affiliation: Department of Dermatology, University Hospital, Cleveland, Ohio.
authors.forename: Kord
authors.initials: K
authors.lastname: Honda
authors.affiliation: Department of Dermatology, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Allison
authors.initials: A
authors.lastname: Vidimos
authors.affiliation: Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, Ohio.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Schluchter
authors.affiliation: Akrotome Imaging Inc, Cleveland, Ohio.
authors.forename: Brian
authors.initials: B
authors.lastname: Straight
authors.affiliation: Department of Pathology, Stanford University, Stanford, California; Department of Microbiology and Immunology, Stanford University, Stanford, California.
authors.forename: Matthew
authors.initials: M
authors.lastname: Bogyo
authors.affiliation: Department of Dermatology, University Hospital, Cleveland, Ohio.
authors.forename: Daniel
authors.initials: D
authors.lastname: Popkin
authors.affiliation: Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio; Department of Radiology, Case Western Reserve University, Cleveland, Ohio; National Foundation for Cancer Research Center for Molecular Imaging, Case Western Reserve University, Cleveland, Ohio. Electronic address: james.basilion@case.edu.
authors.forename: James P
authors.initials: JP
authors.lastname: Basilion
mesh_terms: D006801:Humans; D012878:Skin Neoplasms / Q000473:pathology*; D013997:Time Factors
keywords: cathepsin-B; cathepsin-L; molecular optical imaging; nonmelanoma skin cancer; quenched activity-based probe; re-excision rate; topical application