BG12 A case of severe gastrointestinal bleeding while on vismodegib therapy

Abstract We report the case of a 50-year-old woman, with history Gorlin syndrome on vismodegib therapy, who presented two episodes upper gastrointestinal bleeding (UGIB) in absence other risk factors. is rare disorder characterized by multiple basal cell carcinomas (BCCs) secondary to mutation PTCH1. Mutations PTCH1 lead dysregulation hedgehog signalling pathway and subsequent abnormal proliferation. Vismodegib systemic inhibitor that has been shown be effective treating advanced BCCs syndrome. Our patient acquired which excision, photodynamic therapy topical chemotherapy agents failed control. Therefore, decision commence was made. During treatment vismodegib, she had perforated ulcer required an emergency laparotomy. stopped, but over next few years, her progressed again excess 50 BCCs, including large plaques carcinoma measuring up 12 cm diameter. restarted high-dose proton–pump cover, as recommended gastroenterology team, were largely resolved. However, second bleed occurred approximately 1 year after restarting treatment. Gastroscopies undertaken following these normal, showing mild, nonerosive duodenitis only, Helicobacter pylori testing negative. Given lack pre-existing factors temporal relation made suspend drug. To our knowledge, this first reported literature UGIB associated vismodegib. A separate colonic mucosal changes chronic diarrhoea The protein RNA expression have found present endothelium mesenchyme. Evidence suggests activation lining involved wound-healing response, endothelial turnover mesenchymal immune responses. inhibition via could potentially impair essential maintenance endothelium. postulate mechanism led presentation patient, through damage exposure vessels leading bleeding. Treatment options for BCC are now limited. one therapies induce remission symptoms reduce disease burden. raise awareness potential adverse event.