There is a growing interest in using anti-ENG (TRC105) antibody therapy to treat patients with cancer,55 but this treatment leads to development of clinical symptoms typical of HHT such as telangiectases.56 We suggest that patients on anti-CD105 therapy are also at increased risk of developing HOHF, and, therefore, heart function and AVM screening will be critical to ensure cardiovascular function is protected in these patients. The gene discussed is ENG; the disease is hereditary hemorrhagic telangiectasia.