Acneiform rash - dermatological adverse event in the therapy with anti-EGFR monoclonal antibodies

Background. Targeted anticancer agents lead not only to higher treatment efficacy, but also to various specific side effects. EGFR overexpression is often associated with the metastatic cancer phenotype and correlates with poor prognosis. Monoclonal antibodies are used to suppress the EGFR-dependent signaling cascade, and have a good therapeutic effect, but with dermatological adverse event in the form of an acneiform rash (AR) in 90% of cases. Objective. Evaluation of the dynamics of AR development in oncological patients receiving treatment with panitumumab, an anti-EGFR monoclonal antibody in infusion form. Methods. Evaluation of the dynamics of the clinical manifestations of AR was carried out in a group of 15 patients with colorectal cancer undergoing therapy with the inclusion of panitumumab in the form of intravenous infusions once every 2 weeks. The follow-up period was 10 weeks. Assessment of the severity of manifestations was performed using the IGA (Investigator's Global Assessment) index on a 5-point scoring system (0-5) daily for 56 days. Results. Acneiform rush developed after the second panitumumab infusion on average of 17.5±3.8 days of treatment with EGFR inhibitors. The undulating dynamics of the skin reaction depending on the infusions of monoclonal antibodies was revealed. The severity of acneiform rash gradually increased, and the tendency to worsen after infusion on the 3-4th day continued. The severity continued until the 7th day after the infusion; then there was a decrease in the activity of the skin reaction and its resumption after the next session of targeted therapy with a gradual increase in severity after each infusion of monoclonal antibodies. Conclusion. The revealed features of the course of AR depending on the infusion of monoclonal antibodies allows prescribing maintenance therapy for AR in the intermittent mode during the period of the expected exacerbation and canceling it before chemotherapy to reduce the drug load.

skin toxicity, acneiform rash, panitumumab, targeted therapy, EGFR inhibitors