Skin rash secondary to bevacizumab in a patient with advanced colorectal cancer and relation to response

Bevacizumab (Avastin) in combination with intravenous 5-fluorouracil-based chemotherapy as first-line as well as second-line treatment of metastatic colorectal cancer improves survival. Although skin rash (type unspecified) has been described in some patients following infusion of bevacizumab, it is not a common toxicity of bevacizumab, while acneiform rash occurs in more than 90% of patients who receive cetuximab (Erbitux), the severity of which appears to be predictive of response. We report a patient with colorectal cancer who developed a rash secondary to bevacizumab that correlated with response. A 40-year-old patient with stage IV colorectal cancer received FOLFOX-4 and bevacizumab, which he tolerated very well except for a skin rash related to bevacizumab. The rash cleared every time bevacizumab was eliminated from the chemotherapy regimen. When use of bevacizumab was resumed, similar rash reappeared. Therefore, we believe that this observation of the rash emergence was linked to bevacizumab administration. The most common toxicities associated with bevacizumab include hypertension, hemorrhage, gastrointestinal perforation, arterial thromboembolism, wound healing and proteinuria. Exfoliative dermatitis and a nonspecific rash have been reported with bevacizumab. This case report, we believe, is the first report of a possible correlation between a rash and a positive drug response associated with bevacizumab, and may initiate further investigation of similar observation.