title: Immunoscopy--a technique combining endoscopy and immunofluorescence for diagnosis of colorectal carcinoma.
abstract: BACKGROUND
  Colorectal carcinoma is a common malignant disease with a high mortality rate. It arises most frequently in adenomas of the colorectum with different grades of dysplasia. Endoscopy and biopsy are among the most reliable diagnostic tools currently available. Diagnosis of malignancy at an early stage is sometimes difficult. This study reports on a new method, "immunoscopy", that combines endoscopy and immunofluorescent diagnostic procedures; it is the first reported use of locally applied fluorescein-labeled antibodies for detection of colorectal carcinomas.
  
  
  METHODS
  A monoclonal antibody against carcinoembryonic antigen was fluorescein labeled. In phase I, formalin-fixed tissue samples, and in phase II, postoperative fresh tissue samples from tumorous and nontumorous areas of resected colorectal carcinomas were studied. After being incubated for 10 minutes, specific fluorescence was visualized with a conventional endoscope whose range was increased by means of two narrow band filters.
  
  
  RESULTS
  Because of high levels of autofluorescence, evaluation of immunoscopic investigations using formalin fixed tissue (phase I) was not carried out. Immunoscopic investigation with postoperative fresh tissue samples could differentiate between tumorous and nontumorous areas (p < 0.001). Immunoscopic results were compared with data from immunohistochemical investigations with anti-carcinoembryonic antigen on the same tissue samples.
  
  
  CONCLUSIONS
  Immunoscopy can differentiate between malignant and benign mucosal areas in fresh tissue samples. The high sensitivity of immunoscopy could potentially make it a useful diagnostic complement to routine endoscopy.
authors.affiliation: Department of Medicine B, University of Münster, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Keller
authors.forename: G
authors.initials: G
authors.lastname: Winde
authors.forename: C
authors.initials: C
authors.lastname: Eisenhawer
authors.forename: R
authors.initials: R
authors.lastname: Herwig
authors.forename: H J
authors.initials: HJ
authors.lastname: Terpe
authors.forename: W
authors.initials: W
authors.lastname: Domschke
authors.forename: E C
authors.initials: EC
authors.lastname: Foerster
mesh_terms: D000236:Adenoma / Q000175:diagnosis / Q000276:immunology; D002272:Carcinoembryonic Antigen / Q000032:analysis; D002277:Carcinoma / Q000175:diagnosis / Q000276:immunology; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000276:immunology* / Q000473:pathology; D016145:Endoscopy, Digestive System / Q000295:instrumentation* / Q000379:methods; D005455:Fluorescent Antibody Technique; D006801:Humans
chemical_list: D002272:Carcinoembryonic Antigen