Erlotinib and the Risk of Oral Cancer: The Erlotinib Prevention of Oral Cancer (EPOC) Randomized Clinical Trial

Abstract

Importance: Standard molecularly based strategies to predict and/or prevent oral cancer development in patients with oral premalignant lesions (OPLs) are lacking.

Objective: To test if the epidermal growth factor receptor inhibitor erlotinib would reduce oral cancer development in patients with high-risk OPLs defined by specific loss of heterozygosity (LOH) profiles. Secondary objectives included prospective determination of LOH as a prognostic marker in OPLs.

Design: The Erlotinib Prevention of Oral Cancer (EPOC) study was a randomized, placebo-controlled, double-bind trial. Accrual occurred from November 2006 through July 2012, with a median follow-up time of 35 months in an ambulatory care setting in 5 US academic referral institutions. Patients with OPLs were enrolled in the protocol, and each underwent LOH profiling (N = 379); they were classified as high-risk (LOH-positive) or low-risk (LOH-negative) patients based on their LOH profiles and oral cancer history. The randomized sample consisted of 150 LOH-positive patients.

Interventions: Oral erlotinib treatment (150 mg/d) or placebo for 12 months.

Main outcomes and measures: Oral cancer-free survival (CFS).

Results: A total of 395 participants were classified with LOH profiles, and 254 were classified LOH positive. Of these, 150 (59%) were randomized, 75 each to the placebo and erlotinib groups. The 3-year CFS rates in placebo- and erlotinib-treated patients were 74% and 70%, respectively (hazard ratio [HR], 1.27; 95% CI, 0.68-2.38; P = .45). The 3-year CFS was significantly lower for LOH-positive compared with LOH-negative groups (74% vs 87%, HR, 2.19; 95% CI, 1.25-3.83; P = .01). Increased EGFR gene copy number correlated with LOH-positive status (P < .001) and lower CFS (P = .01). The EGFR gene copy number was not predictive of erlotinib efficacy. Erlotinib-induced skin rash was associated with improved CFS (P = .01).

Conclusions and relevance: In this trial, LOH was validated as a marker of oral cancer risk and found to be associated with increased EGFR copy number (the target of the intervention). Erlotinib did not, however, improve CFS in high-risk patients with LOH-positive or high-EGFR-gene-copy-number OPLs. These results support incorporation of LOH testing as a prognostic tool in routine clinical practice but do not support erlotinib use in this setting.

Trial registration: clinicaltrials.gov Identifier: NCT00402779.

Figure 1. Flow Diagram of Study Enrollment

LOH indicates loss of heterozygosity.

Figure 2. Oral Cancer–Free Survival (CFS) in Study Participants With Loss of Heterozygosity in the Erlotinib vs Placebo Study Arms

E/N indicates number of participants who experienced a cancer or death event/total number of participants; HR, hazard ratio.

Figure 3. Oral Cancer–Free Survival (CFS) According to 3 Study Parameters

E/N indicates number of participants who experienced a cancer or death event/total number of participants; FISH, fluorescence in situ hybridization; HR, hazard ratio; LOH, loss of heterozygosity.

Figure 4. Oral Cancer–Free Survival (CFS) in Erlotinib-Treated Participants

A, Effects of erlotinib on subgroups of interest. B, Landmark analysis of the association between CFS and 1-month rash (n = 74; 1 patient randomized to the erlotinib arm withdrew study consent before the 1-month landmark). E/N indicates number of participants who experienced a cancer or death event/total number of participants; FISH, fluorescence in situ hybridization; HR, hazard ratio; LOH, loss of heterozygosity.