Outcome impact of PIK3CA mutations in HER2-positive breast cancer patients treated with trastuzumab.
Br J Cancer
; 108(9): 1807-9, 2013 May 14.
Article
in En
| MEDLINE
| ID: mdl-23612454
ABSTRACT
BACKGROUND:
Phosphatidylinositol 3-kinase (PI3K) pathway activation has been suggested to negatively influence response to anti-HER2 therapy in breast cancer patients. The present study focused on mutations of the PIK3CA gene, encoding one of the two PI3K subunits.METHODS:
PIK3CA mutations were assessed by direct sequencing in 80 HER2-positive patients treated with 1 year of trastuzumab. All patients preoperatively received four cycles of anthracycline-based chemotherapy, followed by four cycles of docetaxel and 1 year of trastuzumab, starting either before surgery with the first cycle of docetaxel and continuing after surgery (neoadjuvant trastuzumab arm, n=43), or only after surgery (adjuvant trastuzumab arm, n=37).RESULTS:
PIK3CA mutations were found in 17 tumours (21.3%). Better disease-free survival (DFS) was observed in patients with PIK3CA wild-type compared with mutated tumours (P=0.0063). By combining PIK3CA status and treatment arms, four separate prognostic groups with significantly different DFS (P=0.0013) were identified.CONCLUSION:
These results confirm that the outcome of HER2-positive patients treated with trastuzumab is significantly worse in patients with PIK3CA-mutated compared with wild-type tumours.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Breast Neoplasms
/
Receptor, ErbB-2
/
Phosphatidylinositol 3-Kinases
/
Antibodies, Monoclonal, Humanized
/
Antineoplastic Agents
Type of study:
Prognostic_studies
Limits:
Female
/
Humans
Language:
En
Journal:
Br J Cancer
Year:
2013
Document type:
Article
Affiliation country: