28127 Rare development of telangiectasias secondary to trastuzumab use

Abstract

A 64-year-old female with a history of invasive lobular breast carcinoma that is ER+, PR+, HER 2/neu3+, currently on trastuzumab-emtansine (T-DM1), presented with a new red lesion on her forehead for the last six months. The lesion had not changed in size and was not pruritic, bleeding, or painful. She also noted new “broken blood vessels” on her right arm. On exam, an erythematous stellate dilated vessel was noted on the forehead and was blanchable upon dermoscopy. She denied frequent alcohol consumption, liver disease, rosacea, or recent topical corticosteroid use. Family history is significant for breast, cervical, and uterine cancer. Complete blood work revealed mild transaminitis, thrombocytopenia, hypoalbuminemia, and hyperbilirubinemia. Abdominal ultrasound showed mild hepatic steatosis. Sudden appearance of telangiectasias can be due to liver disease, hormonal imbalance, idiopathically, or secondary to medication use. Trastuzumab is a monoclonal antibody against the HER-2 tyrosine kinase receptor and is commonly used in the treatment of breast cancer. Transaminitis is a common side effect of T-DM1. As such, it is postulated that liver injury may play a role in the appearance of telangiectasias while on T-DM1. Dilated vessels can appear on the skin, but also mucosal surfaces, which have a higher propensity to bleed. We suspect our patient’s telangiectasias were secondary to trastuzumab use, as no other causes were identified. Patient was continued on trastuzumab. We recommend monitoring for potential complications of epistaxis and hematochezia. We offered pulse-dye laser therapy should the lesions become problematic in the future.