Biomedical Engineering Reference
In-Depth Information
multiparameter assays such as the 21-gene assay demonstrate clinical
utility and recommend their use in specific clinical scenarios.
33,34
These recommendations are based largely upon validation studies
demonstrating a benefit from chemotherapy in high risk subjects
as identified by multiparameter gene expression assay.
35
It is
biologically plausible that high risk populations identified by other
assays might also benefit from chemotherapy, since poor risk
signatures are driven by high expression of proliferation associated
genes that predict response to chemotherapy (particularly in ER-
positive, HER2-negative disease).
36
13.9
Prospective Clinical Trials Evaluating
Multiparameter Assays
Two clinical trials are prospectively evaluating multiparameter
assays in clinical practice.
37
In the TAILORx trial (Trial Assigning
Individualized Options for Treatment), patients 75 years of age or
younger with ER-positive, HER2-negative, axillary node negative
breast cancer who meet established NCCN guidelines for adjuvant
chemotherapy have the treatment assigned or randomized on the
basis of the 21-gene assay results (NCT00310180). Patients with a
low RS are directed to endocrine therapy and with high RS are directed
to chemoendocrine therapy, whereas those with an indeterminate
mid-range RS (11-25) are randomized to receive chemoendocrine
therapy (the standard treatment arm) or endocrine therapy alone
(the experimental arm).
38
In the MINDACT trial (Microarray in Node-
Negative Disease May Avoid Chemotherapy) trial (NCT00433589),
patients with stage I-II breast cancer undergo risk assessment by the
70-gene assay and Adjuvant online, are assigned to endocrine therapy
alone if both genomic and clinical criteria are concordant for low
risk disease and chemoendocrine if concordant for high risk disease;
patients who risk is discordant by genomic and clinical features are
randomized to treatment assigned by clinical or genomic criteria.
13.10
Conclusion
The 21-gene RS assay brings a high degree of precision and
standardization to the biologic characteristics of ER-positive breast
cancer. Although the test identifies patients most likely to benefit
