Annotation Detail

Information
Associated Genes
PIK3CA
Associated Variants
PIK3CA MUTATION
PIK3CA MUTATION
Associated Disease
estrogen-receptor positive breast cancer
Source Database
CIViC Evidence
Description
This was a Swedish study of 270 breast tumors removed from patients with unilateral operable breast cancer, and either lymph node metastases or a tumor diameter >30mm. PIK3CA missense mutations were found in 65/270 (24%) tumors. Of these, 36 (55%) were in exon 20— 33 H1047R, 1 Y10121C, 1 G1049R, and 1 H1047P. The other 30 were missense mutations in exon 9— 11 E542K, 18 E545K, 1 Q546P. Within the group of 188 patients with ER+ tumors, PIK3CA mutation status did not predict response to tamoxifen.
Variant Origin
somatic
Variant Origin
Somatic
Evidence URL
https://civic.genome.wustl.edu/links/evidence_items/6189
Gene URL
https://civic.genome.wustl.edu/links/genes/37
Variant URL
https://civic.genome.wustl.edu/links/variants/311
Rating
3
Evidence Type
Predictive
Disease
Estrogen-receptor Positive Breast Cancer
Evidence Direction
Does Not Support
Drug
Tamoxifen
Evidence Level
B
Clinical Significance
Sensitivity/Response
Pubmed
17575221
Drugs
Drug NameSensitivitySupported
TamoxifenSensitivityfalse