Current Breast Cancer Reports

, Volume 8, Issue 2, pp 73–79 | Cite as

Defining the Prognostic and Predictive Role of PIK3CA Mutations: Sifting Through the Conflicting Data

  • Sana Al-SukhunEmail author
  • Isam Lataifeh
  • Rajaa Al-Sukhun
Biomarkers (S Dawood, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Biomarkers


PIK3CA is one of the most commonly mutated oncogenes in breast cancer, albeit at variable distribution among the different biological subtypes. Overall, it appears that PIK3CA mutations are most likely found in tumors with less aggressive characteristics, especially estrogen receptor (ER)-positive, luminal A tumors. Studies assessing its prognostic or predictive role have reported conflicting data, in part due to different methodologies used for detection and small sample sizes. The majority of reports used retrospective data from clinical trials thus could not exclude the effect of treatment heterogeneity when evaluating prognostic factors, and analysis was not subtype specific. Since breast cancer subtypes differ in terms of biology, treatment, and outcomes, it is critical that the effects of PIK3CA mutations on pathophysiology and therapy responsiveness are analyzed independently in each subtype. This short review discusses these issues and the significance of PIK3CA mutations in relation to the expression of HER2 and hormone receptors.


Breast cancer PIK3CA PI3K Prognosis Predictive Biomarkers Hormone receptor HER2 receptor ERBB2 Androgen receptor Triple negative breast cancer Genomics Genomic evaluation 


Compliance with Ethical Standards

Conflict of Interest

Sana Al-Sukhun, Isam Lataifeh, and Rajaa Al-Sukhun declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Sana Al-Sukhun
    • 1
    Email author
  • Isam Lataifeh
    • 2
  • Rajaa Al-Sukhun
    • 3
  1. 1.Sukhun Oncology PracticeAl Hyatt Medical CentreAmmanJordan
  2. 2.Department of Obstetrics and GynecologyJordan University of Science and TechnologyIrbidJordan
  3. 3.Independent Scientist/ pharmacokineticsMilpitasUSA

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