title: Tumor resensitization to erlotinib following brief substitution of cetuximab.
abstract: Targeted inhibition of epidermal growth factor receptors (EGFR) is becoming a standard anticancer treatment in defined clinical scenarios. EGFR inhibition may be achieved either by small-molecule orally bioavailable tyrosine kinase inhibitors, such as gefitinib or erlotinib, or else by large-molecule receptor antibodies, such as cetuximab or panitumumab. Here, we describe a case of pancreatic cancer in which the small-molecule EGFR antagonist erlotinib was used before and after the EGFR antibody cetuximab, with unexpected potentiation of both toxic and therapeutic sequelae.
authors.affiliation: Division of Haematology and Oncology, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 802, Administration Block, Pokfulam, Hong Kong, China. repstein@hku.hk
authors.forename: R J
authors.initials: RJ
authors.lastname: Epstein
authors.forename: T W
authors.initials: TW
authors.lastname: Leung
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000201:enzymology / Q000556:secondary; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D014408:Biomarkers, Tumor / Q000097:blood; D001859:Bone Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000556:secondary; D000068818:Cetuximab; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives; D003875:Drug Eruptions / Q000209:etiology; D004347:Drug Interactions; D019008:Drug Resistance, Neoplasm; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D000069347:Erlotinib Hydrochloride; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000556:secondary; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors*; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D011799:Quinazolines / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D000093542:Gemcitabine
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D003841:Deoxycytidine; D000069347:Erlotinib Hydrochloride; C512478:EGFR protein, human; D066246:ErbB Receptors; D000068818:Cetuximab; D000093542:Gemcitabine