A phase II study for metabolic in vivo response monitoring with sequential 18FDG-PET-CT during treatment with the EGFR-monoclonal-antibody cetuximab in metastatic colorectal cancer: the Heidelberg REMOTUX trial

The REMOTUX trial is an investigator-initiated, prospective, open-label, single-arm, single-center early exploratory predictive study. The first 18 F-FDG PET-CT is conducted at baseline followed by the run-in phase with cetuximab at days 1 and 8. At day 14, the second 18 F-FDG PET-CT is performed. Subsequently, patients are treated according to the Folfiri-cetuximab regimen as an active and approved first-line regimen for metastatic colorectal carcinoma. At day 56, clinical response is evaluated with a CT-scan compared to the baseline analysis. Tracer uptake is assessed using standardized uptake values (SUVs). The main hypothesis to be tested in the primary analysis is whether or not the relative change in the SUV from baseline to day 14 has any predictive relevance for early clinical response determined at day 56. Patients are followed until death from any cause or until 24 months after the last patient has ended trial treatment.The aim of this trial is to evaluate metabolic changes in metastatic colorectal cancer during short-term single agent treatment with cetuximab and to analyse their potential of predicting early clinical response. This could be helpful to answer the question if early identification of patients not responding to cetuximab is possible.ClinicalTrials.gov NCT200811021020; EudraCT 200901327923Colorectal cancer is one of the three most common types of cancer in men and in women. It is estimated that about 1.2 million new cases were diagnosed worldwide in 2008 and approximately 609.000 deaths occurred [1]. The 5-year overall survival rate for patients with metastatic disease in the western world has increased during the last decade and is nowadays reported to reach about 10% [1]. The median overall survival for patients treated with active combination chemotherapies and monoclonal antibodies (mABs) is nowadays in excess of two years [2].The epidermal growth factor receptor (EGFR) mAB cetuximab has proven activity in metastatic colorectal cancer. In