PIK3CA Mutation CDx – Plasma

Liquid biopsy for detection of PIK3CA mutation

PIK3CA is the most commonly mutated gene in patients with HR+/HER2- advanced or metastatic breast cancer. Consider PIK3CA Mutation CDx - Plasma when breast tumor tissue (either primary or metastatic) is not available or when only decalcified tissue is available. If no PIK3CA mutation is detected in plasma, reflex to testing in tumor tissue.

Factors that may contribute to false negatives in plasma testing

Specimen handling

Up to 20% of false negatives

Biological differences in plasma testing

Up to 25% of false negatives

Observed IVD CDx Differences in plasma & tissue in clinical trials

Up to 40% of false negatives

Ordering PIK3CA Mutation CDx - Plasma

Please complete the prequalification call with NeoGenomics Client Services to review program eligibility and specimen requirements. Prequalified sites will receive PIK3CA Mutation CDx - Plasma supplies.

Call NeoGenomics Client Services!

PIK3CA Mutation CDx- Plasma testing requires the following:

  • Centrifuge (preferred: one capable of 4°C setting) to spin down blood and separate plasma

  • Specimen freezer that can store the specimen at -80°C after plasma separation (-70°C to -90°C is acceptable)

  • Dry ice to use when transporting the specimen to NeoGenomics

  • Please Note: Whole blood collected in K2 EDTA blood collection tubes must be processed to separate plasma within 4 hours of blood collection. Failure to do so may result in test failure.


  • The Cancer Genome Atlas Network. Comprehensive molecular portraits of human breast tumours. Nature. 2012;490(7418):61-70.

  • Bettegowda C, Sausen M, Leary RJ, et al. Detection of circulating tumor DNA in early- and late-stage human malignancies. Sci Transl Med. 2014;6(224):224ra24.

  • Lippi G, Chance JJ, Church S, et al. Preanalytical quality improvement: from dream to reality. Clin Chem Lab Med. 2011;49(7):1113-1126.

  • PIQRAY® (alpelisib) [package insert]. East Hanover, NJ: Novartis Pharmaceuticals Corporation; May 2019.