Faculty Collaboration Database

KRASness and PIK3CAness in patients with advanced colorectal cancer: outcome after treatment with early-phase trials with targeted pathway inhibitors. PLoS One 2012;7(5):e38033

Date

06/08/2012

Pubmed ID

22675430

Pubmed Central ID

PMC3364990

DOI

10.1371/journal.pone.0038033

Scopus ID

2-s2.0-84861704697 (requires institutional sign-in at Scopus site)   45 Citations

Abstract

PURPOSE: To evaluate clinicopathologic and molecular features of patients with metastatic colorectal cancer (mCRC) and their outcomes in early-phase trials using pathway-targeting agents.

PATIENTS AND METHODS: We analyzed characteristics of 238 patients with mCRC referred to the phase 1 trials unit at MD Anderson Cancer Center. KRAS, PIK3CA and BRAF status were tested using PCR-based DNA sequencing.

RESULTS: Fifty-one percent of patients harbored KRAS mutations; 15% had PIK3CA mutations. In the multivariate regression model for clinical characteristics KRAS mutations were associated with an increased incidence of lung and bone metastases and decreased incidence of adrenal metastases; PIK3CA mutations were marginally correlated with mucinous tumors (p = 0.05). In the univariate analysis, KRAS and PIK3CA mutations were strongly associated. Advanced Duke's stage (p<0.0001) and KRAS mutations (p = 0.01) were the only significant independent predictors of poor survival (Cox proportional hazards model). Patients with PIK3CA mutations had a trend toward shorter progression-free survival when treated with anti-EGFR therapies (p = 0.07). Eighteen of 78 assessable patients (23%) treated with PI3K/Akt/mTOR axis inhibitors achieved stable disease [SD] ≥6 months or complete response/partial response (CR/PR), only one of whom were in the subgroup (N = 15) with PIK3CA mutations, perhaps because 10 of these 15 patients (67%) had coexisting KRAS mutations. No SD ≥6 months/CR/PR was observed in the 10 patients treated with mitogen-activating protein kinase (MAPK) pathway targeting drugs.

CONCLUSIONS: KRAS and PIK3CA mutations frequently coexist in patients with colorectal cancer, and are associated with clinical characteristics and outcome. Overcoming resistance may require targeting both pathways.

Author List

Garrido-Laguna I, Hong DS, Janku F, Nguyen LM, Falchook GS, Fu S, Wheler JJ, Luthra R, Naing A, Wang X, Kurzrock R

Author

Razelle Kurzrock MD Center Associate Director, Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Aged
Antineoplastic Agents
Class I Phosphatidylinositol 3-Kinases
Colorectal Neoplasms
Female
Humans
MAP Kinase Signaling System
Male
Middle Aged
Mutation
Mutation Rate
Neoplasm Metastasis
Phosphatidylinositol 3-Kinases
Protein Kinase Inhibitors
Proto-Oncogene Proteins
Proto-Oncogene Proteins c-akt
Proto-Oncogene Proteins p21(ras)
Signal Transduction
TOR Serine-Threonine Kinases
Treatment Outcome
ras Proteins