More than 50% of patients with esophageal cancer have locally advanced or metastatic disease at presentation. The use of chemotherapy for this patient group is increasing with the intention of local and distant tumor control, improving quality of life and prolongation of survival. The most frequently used agents are 5-fluorouracil, cisplatin, with or without various anthracyclines. Cisplatin plus continuous 5-fluorouracil are the standard of care regimens. Taxanes and anthracyclins are eligible agents for possible future studies, however with higher incidences of toxicities and life threatening complications. Response rates for single agents range from 15%-30%. Combination regimens usually tend to produce higher response rates and occasionally patients achieve complete responses (0%-11%). However, with the combination regimens, the median survival time remains clearly less than 10 months, mostly between 4-8 months \[Homs MY et al\]. In comparison of different chemotherapy protocols, there was no consistent benefit of any specific chemotherapy regimen. So far, cisplatin combined with 5-fluorouracil is one of the approved standard regimens in esophageal cancer world wide\[Medical Research Council Oesophageal Cancer Group\]. This so called three-weekly MRC regimen has a better toxicity profile than the four weekly CF regimen given in Central Europe with the higher Cisplatin dose\[Lorenzen S et al\], but less overall chemotherapy given per 4 months.

Advances in molecular biology and new molecular technologies can possibly contribute to improvement of response to neoadjuvant or palliative therapy in ESCC patients as well. EGFR1 blockade with platinum-based chemotherapy already significantly improved response rates as well as the progression-free and overall survival compared to chemotherapy alone in patients with head and neck tumors, which are also squamous cancers\[Vermorken JB et al\].

Even more, the Arbeitsgemeinschaft Internistische Onkologie (AIO) has performed a randomized phase II study of the EGFR antibody cetuximab plus cisplatin/5-fluorouracil versus cisplatin/5-fluorouracil alone in first-line metastatic ESCC\[Lorenzen S et al\]. For a maximum of six 28-day cycles, patients received cisplatin 100 mg/m(2), day 1, plus 5-FU 1000 mg/m(2) days 1-5 (CF), either alone or in combination with cetuximab (CET-CF). The primary endpoint was tumor response. From 62 eligible patients included, 32 receiving CET-CF and 30 CF. Cetuximab weekly did not exacerbate grade 3/4 toxicity, except for rash (6% vs 0%) and diarrhea (16% vs 0%). The overall response rate according to RECIST criteria were 19% and 13% and the disease control rates, were 75% and 57% for the CET-CF and CF arms, respectively. With a median follow-up of 21.5 months, the median progression-free survival was 5.9 and 3.6 months and median overall survival 9.5 and 5.5 months for CET-CF and CF, respectively. No KRAS codon 12/13 tumor mutations were identified in the 37 evaluated samples.

Thus, with respect to the AIO data and in concordance with the head and neck data by Vermorken, EGFR antibody targeted therapy may not only be safely combined with CF, but may also very likely increase the efficacy of standard CF, particularly with regard to a chosen primary endpoint of overall survival. Therefore, the aim of this study is to investigate if the overall survival of patients with squamous cell carcinoma of the esophagus can be prolonged if panitumumab is added to the standard CF chemotherapy.