Annotation Detail

Information
Associated Genes
PIK3CA
Associated Variants
PIK3CA MUTATION
PIK3CA MUTATION
Associated Disease
breast cancer
Source Database
CIViC Evidence
Description
This study of 140 patients with stage II-III breast cancer assessed the response of patients with PIK3CA mutations to 6 months of preoperative chemotherapy. 23/170 patients had PIK3CA mutations. Of those patients, 12 received six courses of 5-fluorouracil, doxorubicin (or epirubicin), and cyclophosphamide; this treatment group contained 7 patient with E545K mutations, 1 with E542K, and 4 with H1047R. The other 11 patients received 12 weekly courses of paclitaxel followed by four courses of 5-fluorouracil, doxorubicin (or epirubicin), and cyclophosphamide; this treatment group contained 1 patient with an E545K mutation, 1 with Q546R, 1 with E542K, 1 with E542V, 5 with H1047R, 1 with G1049R, and 1 with H1047T. The study did not find evidence that PIK3CA mutations are associated with preoperative chemotherapy sensitivity in breast cancer treated with an anthracycline (doxorubicin or epirubicin), 5-fluorouracil and cyclophosphamide regardless of whether paclitaxel was also administered. The lack of association was true of estrogen receptor (ER)-positive and ER-negative tumors.
Variant Origin
somatic
Variant Origin
Somatic
Evidence URL
https://civic.genome.wustl.edu/links/evidence_items/6191
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
Breast Cancer
Evidence Direction
Does Not Support
Drug
Fluorouracil,Doxorubicin,Cyclophosphamide,Epirubicin,Paclitaxel
Evidence Level
B
Clinical Significance
Sensitivity/Response
Pubmed
18371219
Drugs
Drug NameSensitivitySupported
CyclophosphamideSensitivityfalse
DoxorubicinSensitivityfalse
EpirubicinSensitivityfalse
FluorouracilSensitivityfalse
PaclitaxelSensitivityfalse