1. Validation of the IHC4 Breast Cancer Prognostic Algorithm Using Multiple Approaches on the Multinational TEAM Clinical Trial
- Author
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Bartlett, John M.S., Christiansen, Jason, Gustavson, Mark, Rimm, David L., Piper, Tammy, van de Velde, Cornelis J.H., Hasenburg, Annette, Kieback, Dirk G., Putter, Hein, Markopoulos, Christos J., Dirix, Luc Y., Seynaeve, Caroline, and Rea, Daniel W.
- Subjects
Clinical trials -- Models -- Health aspects ,Algorithms -- Models -- Health aspects ,Recurrence (Disease) -- Models -- Health aspects ,Immunohistochemistry -- Models -- Health aspects ,Medical research -- Models -- Health aspects ,Tamoxifen -- Models -- Health aspects ,Exemestane -- Models -- Health aspects ,Breast cancer -- Models -- Health aspects ,Algorithm ,Health - Abstract
Context.--Hormone receptors HER2/neu and Ki-67 are markers of residual risk in early breast cancer. An algorithm (IHC4) combining these markers may provide additional information on residual risk of recurrence in patients treated with hormone therapy. Objective.--To independently validate the IHC4 algorithm in the multinational Tamoxifen Versus Exemestane Adjuvant Multicenter Trial (TEAM) cohort, originally developed on the trans-ATAC (Arimidex, Tamoxifen, Alone or in Combination Trial) cohort, by comparing 2 methodologies. Design.--The IHC4 biomarker expression was quantified on TEAM cohort samples (n = 2919) by using 2 independent methodologies (conventional 3,30-diaminobezidine [DAB] immunohistochemistry with image analysis and standardized quantitative immunofluorescence [QIF] by AQUA technology). The IHC4 scores were calculated by using the same previously established coefficients and then compared with recurrence-free and distant recurrence-free survival, using multivariate Cox proportional hazards modeling. Results.--The QIF model was highly significant for prediction of residual risk (P < .001), with continuous model scores showing a hazard ratio (HR) of 1.012 (95% confidence interval [95% CI]: 1.010-1.014), which was significantly higher than that for the DAB model (HR: 1.008, 95% CI: 1.006-1.009); P < .001). Each model added significant prognostic value in addition to recognized clinical prognostic factors, including nodal status, in multivariate analyses. Quantitative immunofluorescence, however, showed more accuracy with respect to overall residual risk assessment than the DAB model. Conclusions.--The use of the IHC4 algorithm was validated on the TEAM trial for predicting residual risk in patients with breast cancer. These data support the use of the IHC4 algorithm clinically, but quantitative and standardized approaches need to be used. (Arch Pathol Lab Med. 2016; 140:66-74; doi: 10.5858/arpa.2014-0599-OA), With progressively improving outcomes, particularly for patients with estrogen receptor (ER)-positive early breast cancers, personalized risk stratification to direct appropriate therapy is increasingly important. Multiple approaches to the assessment of [...]
- Published
- 2016
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