title: Lack of usefulness of epidermal growth factor receptor expression determination for cetuximab therapy in patients with colorectal cancer.
abstract: In patients with metastatic colorectal cancer, the use of cetuximab currently requires a documented tumoral epidermal growth factor receptor positivity. Responses to cetuximab, however, have been described in patients with epidermal growth factor receptor-negative tumors. We have used cetuximab in all eligible patients with metastatic colorectal cancer, whether their tumor expressed epidermal growth factor receptor or not. We assessed the cetuximab efficacy with regard to tumoral epidermal growth factor receptor expression. Twenty patients with metastatic colorectal cancer were treated off study with cetuximab and irinotecan after failure of oxaliplatin- and irinotecan-based regimens. Tumors were analyzed in all patients for epidermal growth factor receptor expression by immunohistochemistry. Tumors were positive for epidermal growth factor receptor in 12 cases and negative in eight cases. An objective response to cetuximab-based therapy was obtained in four patients (20%). Tumors of these four patients were negative for epidermal growth factor receptor expression. These results provide further evidence for the lack of usefulness of epidermal growth factor receptor detection by immunohistochemistry for cetuximab therapy in patients with metastatic colorectal cancer.
authors.affiliation: Department of Medical Oncology, Universitary Hospital, Lille, France. m-hebbar@chru-lille.fr
authors.forename: Mohamed
authors.initials: M
authors.lastname: Hebbar
authors.forename: Agnès
authors.initials: A
authors.lastname: Wacrenier
authors.forename: Christophe
authors.initials: C
authors.lastname: Desauw
authors.forename: Olivier
authors.initials: O
authors.lastname: Romano
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cattan
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Triboulet
authors.forename: François-René
authors.initials: FR
authors.lastname: Pruvot
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use; D015415:Biomarkers; D002166:Camptothecin / Q000031:analogs & derivatives / Q000627:therapeutic use; D000068818:Cetuximab; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D066246:ErbB Receptors / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D000077146:Irinotecan; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D013534:Survival
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000972:Antineoplastic Agents, Phytogenic; D015415:Biomarkers; D000077146:Irinotecan; D066246:ErbB Receptors; D000068818:Cetuximab; D002166:Camptothecin