Blood-based markers of efficacy and resistance to cetuximab treatment in metastatic colorectal cancer: results from CALGB 80203 (Alliance).

Abstract

Circulating protein markers were assessed in patients with colorectal cancer (CRC) treated with cetuximab in CALGB 80203 to identify prognostic and predictive biomarkers. Patients with locally advanced or metastatic CRC received FOLFOX or FOLFIRI chemotherapy (chemo) or chemo in combination with cetuximab. Baseline plasma samples from 152 patients were analyzed for six candidate markers [epidermal growth factor (EGF), heparin-binding EGF (HBEGF), epidermal growth factor receptor (EGFR), HER2, HER3, and CD73]. Analyte levels were associated with survival endpoints using univariate Cox proportional hazards models. Predictive markers were identified using a treatment-by-marker interaction term in the Cox model. Plasma levels of EGF, HBEGF, HER3, and CD73 were prognostic for overall survival (OS) across all patients (KRAS mutant and wild-type). High levels of EGF predicted for lack of OS benefit from cetuximab in KRAS wild-type (WT) patients (chemo HR = 0.98, 95% CI = 0.74-1.29; chemo+cetuximab HR = 1.54, 95% CI = 1.05-2.25; interaction P = 0.045) and benefit from cetuximab in KRAS mutant patients (chemo HR = 1.72, 95% CI = 1.02-2.92; chemo+cetuximab HR = 0.90, 95% CI = 0.67-1.21; interaction P = 0.026). Across all patients, higher HER3 levels were associated with significant OS benefit from cetuximab treatment (chemo HR = 4.82, 95% CI = 1.68-13.84; chemo+cetuximab HR = 0.95, 95% CI = 0.31-2.95; interaction P = 0.046). CD73 was also identified as predictive of OS benefit in KRAS WT patients (chemo HR = 1.28, 95% CI = 0.88-1.84; chemo+cetuximab HR = 0.60, 95% CI = 0.32-1.13; interaction P = 0.049). Although these results are preliminary, and confirmatory studies are necessary before clinical application, the data suggest that HER3 and CD73 may play important roles in the biological response to cetuximab.

• Authors: Ace J Hatch, Alexander B Sibley, Mark D Starr, J Chris Brady, Chen Jiang, Jingquan Jia, Daniel L Bowers, Herbert Pang, Kouros Owzar, Donna Niedzwiecki, Federico Innocenti, Alan P Venook, Herbert I Hurwitz, Andrew B Nixon, Alliance for Clinical Trials in Oncology
• Journal: Cancer medicine (Cancer Med) Vol. 5 Issue 9 Pg. 2249-60 (09 2016) ISSN: 2045-7634 [Electronic] United States
• PMID: 27465221 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Chemical References

• Antineoplastic Agents
• Biomarkers, Tumor
• ras Proteins
• Cetuximab

Topics

• Adult
• Aged
• Aged, 80 and over
• Antineoplastic Agents (administration & dosage, therapeutic use)
• Antineoplastic Combined Chemotherapy Protocols (adverse effects, therapeutic use)
• Biomarkers, Tumor (blood)
• Cetuximab (administration & dosage, therapeutic use)
• Colorectal Neoplasms (blood, drug therapy, mortality, pathology)
• Drug Resistance, Neoplasm
• Female
• Humans
• Kaplan-Meier Estimate
• Male
• Middle Aged
• Mutation
• Neoplasm Metastasis
• Neoplasm Staging
• Prognosis
• Young Adult
• ras Proteins (genetics)