Automated objective determination of percentage of malignant nuclei for mutation testing

Appl Immunohistochem Mol Morphol. 2014 May-Jun;22(5):363-71. doi: 10.1097/PAI.0b013e318299a1f6.

Abstract

Detection of DNA mutations in tumor tissue can be a critical companion diagnostic test before prescription of a targeted therapy. Each method for detection of these mutations is associated with an analytic sensitivity that is a function of the percentage of tumor cells present in the specimen. Currently, tumor cell percentage is visually estimated resulting in an ordinal and highly variant result for a biologically continuous variable. We proposed that this aspect of DNA mutation testing could be standardized by developing a computer algorithm capable of accurately determining the percentage of malignant nuclei in an image of a hematoxylin and eosin-stained tissue. Using inForm software, we developed an algorithm, to calculate the percentage of malignant cells in histologic specimens of colon adenocarcinoma. A criterion standard was established by manually counting malignant and benign nuclei. Three pathologists also estimated the percentage of malignant nuclei in each image. Algorithm #9 had a median deviation from the criterion standard of 5.4% on the training set and 6.2% on the validation set. Compared with pathologist estimation, Algorithm #9 showed a similar ability to determine percentage of malignant nuclei. This method represents a potential future tool to assist in determining the percent of malignant nuclei present in a tissue section. Further validation of this algorithm or an improved algorithm may have value to more accurately assess percentage of malignant cells for companion diagnostic mutation testing.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / diagnosis*
  • Adenocarcinoma / genetics
  • Adenocarcinoma / pathology
  • Algorithms
  • Automation, Laboratory
  • Carcinogenesis / genetics
  • Cell Count / methods*
  • Cell Count / standards
  • Cell Differentiation / genetics
  • Colonic Neoplasms / diagnosis*
  • Colonic Neoplasms / genetics
  • Colonic Neoplasms / pathology
  • DNA / analysis*
  • Diagnostic Errors / prevention & control
  • Humans
  • Mutation / genetics*
  • Observer Variation
  • Reference Standards
  • Software

Substances

  • DNA