Source: medpagetoday.comAuthor: Charles Bankhead, Staff Writer, MedPage TodayDate: March 05, 2013    The addition of targeted agents to standard chemotherapy failed to improve efficacy in two different trials of advanced head and neck cancer. In one trial, patients given gefitinib (Iressa) in addition to docetaxel lived about a month longer than those who received docetaxel plus placebo. In the other trial, adding erlotinib (Tarceva) to cisplatin-based chemoradiation did not improve response rate or progression-free survival. However, neither regimen was associated with increased toxicity compared with standard chemotherapy, investigators reported online in the Journal of Clinical Oncology. Noting the lack of useful biomarkers to guide the use of targeted agents, the authors of an accompanying editorial said that experience to date suggests current strategies amount to "skimming the surface of a problem that is exceedingly complex." "It is unlikely that genomic sequencing alone will represent a panacea to the therapeutic challenges in squamous cell carcinoma of the head and neck," said Aaron R. Hansen, MBBS, and Lillian L. Siu, MD, of Princess Margaret Cancer Center in Toronto. "Comprehensive characterization that encompasses a broader omics-based molecular evaluation, as well as immune function assessments, is urgently needed." The rationale for the gefitinib and erlotinib trials came from evidence that the drugs targeting epidermal growth factor receptors (EGFR) have synergism with conventional chemotherapeutic agents, have radiosensitizing properties, and have demonstrated modest activity as monotherapy in some clinical studies. Cetuximab (Erbitux), another EGFR inhibitor, has been approved for use with radiation therapy or as monotherapy [...]