Modified true-color computer-assisted image analysis versus subjective scoring of estrogen receptor expression in breast cancer: A comparison

Background: Hormone receptor expression can be quantified by computerized i mage analysis in immunohistochemically stained specimens. When comparing se miquantitative scoring with computerized image analysis a review of the lit erature shows contradictory findings concerning the correlation of these tw o methods. Recent technical approaches have been developed with true-color computer-assisted image analysis facilitating new measurement designs. We p erformed a study with a new approach using the principle of semiquantitativ e assessment of hormone receptor content and measuring two different binary images (immunohistochemically stained nuclear area and total nuclear area) . Material and Methods: Eighty formalin-fixed, paraffin-embedded and immuno histochemically stained breast cancer specimens were assessed for estrogen receptor expression by true color computer-assisted image analysis and by c onventional light microscopy scoring according to Remmele (immunoreactive s core (IRS)=staining intensify (SI) x percentage of positive cells (PP)). Th e results of both methods were correlated. Results: Mean optical density (M OD) and subjective scoring of SI as well as stained nuclear area vs. total nuclear area and subjective scoring of stained cells (PP) showed a high cor relation (Spearman correlation coefficient: 0,95, p-value: 0,0001 and 0,64, p-value: 0,0001, respectively). Conclusion: On the basis of this new techn ical approach our results confirm the correlation of semiquantitative hormo ne receptor scoring and quantitative computer-assisted image analysis. We b elieve that by automating electronic analysis in the near future We will be able to establish reliable observer-independent evaluation of immunohistoc hemical variables ensuing comparability in multi-center trials and cost eff iciency.