TargetPrint® Validation


TargetPrint has been validated on over 500 breast cancer tumor samples from three independent studies. Validation was achieved using Immunohistochemistry tests (IHC) performed at an independent US-based, CLIA and CAP accredited national reference laboratory for comparison. 

 

The Estrogen Receptor (ER), Progesterone Receptor (PR) and HER2 microarray values were compared to the IHC results which were assessed at one central laboratory, yielding a 93% concordance (95CI: 91-95%) for ER, an 83% concordance (95CI: 80-86%) for PR and a 96% concordance (95CI: 94-98%) for HER2, respectively.  For ER and PR, a threshold of 1% IHC positively stained tumor cells was used to classify samples as positive; for HER2, an IHC score of 3+ was considered positive. In the case of 2+ samples, FISH assessed final HER2 amplification status.(13,14) 

References
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