PIK3CA Mutation CDx - Plasma is an FDA-approved qualitative companion diagnostic assay performed on cell-free circulating tumor DNA extracted from the peripheral blood plasma of certain breast cancer patients to detect 10 mutations in exons 7, 9, and 20 of the PIK3CA gene. Plasma testing is appropriate when no primary or metastatic breast tumor tissue is available, or the only available tissue is decalcified and therefore unsuitable for molecular testing. Tissue is the recommended specimen type in all other cases.
Please see FAQs and more about options to test plasma in conjunction with tissue here.
This test is intended to identify PIK3CA mutations in patients with advanced hormone receptor-positive, HER2-negative (HR+/HER2-) breast cancer who may be candidates for therapy with the PI3K alpha-specific inhibitor PIQRAY® (alpelisib).
- Peripheral blood: Please contact Client Services at 866-776-5907, option 3, to review special collection and handling requirements and to receive the test request form and shipping supplies.
Please contact Client Services.
- therascreen® PIK3CA RGQ PCR [package insert]. Hilden, Germany: QIAGEN.
- Andre F, Ciruelos E, Rubovszky G, et al. Alpelisib for PIK3CA-mutated, hormone receptor-positive advanced breast cancer. N Engl J Med. 2019;380(20):1929-1940.
- Sabine V, Crozier C, Brookes C, et al. Mutational analysis of PI3K/AKT signaling pathway in tamoxifen exemestane adjuvant multinational pathology study. J Clin Oncol. 2014;32:2951-2958.