123318-143

The initial report of RTOG 0436: A phase III trial evaluating the addition of cetuximab to paclitaxel, cisplatin, and radiation for patients with esophageal cancer treated without surgery.

Category: 
Cancers of the Esophagus and Stomach
Session Type and Session Title: 
General Poster Session A: Cancers of the Esophagus and Stomach
Oral Abstract Session: Cancers of the Esophagus and Stomach (eQ&A)
Abstract Number: 
LBA6
Citation: 
J Clin Oncol 32, 2014 (suppl 3; abstr LBA6)
Author(s): 
Mohan Suntharalingam, Kathryn Winter, David H. Ilson, Adam Dicker, Lisa A. Kachnic, Andre A. Konski, Bapsi Chakravarthy, David K. Gaffney, Harish V. Thakrar, Margit Naomi Horiba, Melvin Deutsch, Vivek Kavadi, Adam Raben, Kevin S. Roof, Gregory M. M. Videtic, Jondavid Pollock, Howard Safran, Christopher H. Crane; University of Maryland Marlene and Stewart Greenebaum Cancer Center, Baltimore, MD; Radiation Therapy Oncology Group-Statistical Center, Philadelphia, PA; Memorial Sloan-Kettering Cancer Center, New York, NY; Department of Radiation Oncology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA; Boston University Medical Center, Boston, MA; Karmanos Cancer Institute/Wayne State University, Detroit, MI; Vanderbilt-Ingram Cancer Center, Nashville, TN; Huntsman Cancer Hospital at University of Utah, Salt Lake City, UT; John H. Stronger, Jr. Hospital of Cook County Minority-Based Community Clinical Oncology Program, Chicago, IL; University of Maryland, Baltimore, MD; UPMC Shadyside, Pittsburgh, PA; Texas Oncology, Sugarland, TX; Helen F. Graham Cancer Center, Wilmington, DE; Southeast Radiation Oncology, Charlotte, NC; Cleveland Clinic Foundation, Cleveland, OH; Schiffler Cancer Center, Wheeling, WV; Brown University Oncology Research Group, Providence, RI; The University of Texas MD Anderson Cancer Center, Houston, TX

Abstracts that were granted an exception in accordance with ASCO's Conflict of Interest Policy are designated with a caret symbol (^).

Abstract Disclosures

Abstract: 

Background: RTOG 0436 is a randomized Ph III trial designed to evaluate the benefit of cetuximab added to the concurrent chemoradiation for patients undergoing non-operative management of esophageal carcinoma. Methods: Pts with biopsy-proven squamous cell or adenocarcinoma of the esophagus (T1N1M0; T2-4 AnyN M0; Any T/N M1a) were randomized to weekly concurrent cisplatin (50 mg/m2), paclitaxel (25 mg/m2), and daily radiation 50.4 Gy/1.8 Gy fractions ± weekly cetuximab (400 mg/m2 day 1 then weekly 250 mg/m2). Patients were stratified by histology, tumor size (< 5 cm vs > 5cm), and the status of celiac lymph nodal involvement. Overall survival (OS) was the primary endpoint, with a planned accrual of 420 pts to detect an increase in 2-year OS from 41% to 53%; 80% power and 1-sided 0.025 alpha. An interim analysis of cCR was planned for the first 150 of each histology. Results: The study accrued 344 pts from 2008-2013 and 328 were eligible. Based on interim analyses, the study stopped accruing adeno pts in 5/2012 and SCC pts in 1/2013. Pts were well matched for pretreatment characteristics: 80% with T3/4 disease, 66% N1, and 19% with celiac nodal involvement. Incidence of grade 3/4/5 treatment (tx) related AEs was 45%, 22%, 4% in Arm 1 (cetuximab) and 49%, 17%, 1% in Arm 2 (no cetuximab). A cCR rate of 56% was observed in Arm 1 vs 59% in Arm 2 (p=0.72). No differences were seen in cCR between tx arms for either histology. The 12 and 24 mo OS rates for cCR pts were 79% and 58% vs 53% and 30% for those with residual disease (p<0.0001). Median follow-up for all pts is 15.4 mos. The 12 and 24 mo OS (95% CI) for Arm 1 is 64% (56%, 71%) and 44% (36%, 52%) vs 65% (57%, 72%) and 42% (34%, 50%) for Arm 2 (p=0.70). Adeno pts (n=203) had a 12 and 24 mo OS of 65% and 43% for Arm 1 vs 64% and 41% for Arm 2 (p=0.37). The 12 and 24 mo OS for the 125 SCC pts was 62% and 46% for Arm 1 vs 67% and 43% for Arm 2 (p=0.97). Conclusions: The addition of cetuximab to concurrent chemoradiation did not improve OS. There were no differences in cCR rates by tx arm. These Ph III results point to little benefit for current EGFR targeted agents in the tx of esophageal cancer. Supported by RTOG CA21661 and CCOP CA3742 NCI grants and Bristol Myers Squibb. Clinical trial information: NCT00655876.