Measurement of ER and PR status in breast cancer using the QuantiGene2.0 assay.

AIM

The QuantiGene2.0 assay has low interlaboratory variability and can directly measure RNA levels without a reverse transcription step or a polymerase chain reaction process. To evaluate the utility of the QuantiGene2.0 assay for the assessment of oestrogen receptor (ER) and progesterone receptor (PR) status as an alternative to immunohistochemistry (IHC), we compared disease-free survival according to quantitative ER and PR measurements when using IHC and the QuantiGene2.0 assay.

METHODS

Samples were collected from 171 patients who underwent breast cancer surgery between January 2003 and December 2006. Cox proportional hazard analysis was performed and concordance between IHC and the QuantiGene2.0 assay for the assessment of ER and PR status was evaluated.

RESULTS

ER and PR assessments were well correlated between IHC and the QuantiGene2.0 assay. The difference in disease-free survival was statistically significant according to expression of PR, but not ER, between the two groups.

CONCLUSIONS

The QuantiGene2.0 assay showed results similar to those of IHC for the assessment of ER and PR in response to treatment. Therefore, our data suggest that the QuantiGene2.0 assay can be used to determine ER and PR status and corroborate IHC findings, which at present are considered as the standard for the evaluation of ER and PR status.