Impact of prophylactic treatments of cetuximab-based skin reactions in patients with metastatic colorectal carcinoma (mCRC): Interim analysis of the German noninterventional study ERBITAG.

675 Background: Prophylactic treatments are widely used to ameliorate skin reactions induced by EGFR inhibition. Randomised studies have shown a positive impact of prophylactic antibiotics. Methods: Patients (Pts) with KRAS-wt and later RAS-wt mCRC treated with a first-line chemotherapy regimen plus cetuximab with written informed consent were eligible for this prospective, non-interventional study. Physicians were requested to complete a questionnaire and document any applied prophylactic and reactive skin toxicity treatment for every pt. Different prophylactic treatment regimens were categorized in 5 groups: systemic antibiotics (SA), skin care without antibiotics or corticosteroids (SC), other topical treatments (OT) (e.g. antibiotics or corticosteroids), any prophylaxis (P), and no prophylaxis (NP). Results: Data from 497 pts at 178 centers were finally collected and evaluable at data cut off. For all reported skin reactions the maximum NCI-CTCAE grade per patient and prophylactic treatment group was ...