Pancreatic Mucinous-Cystic Neoplasm

Pancreatic mucinous cystic neoplasm (MCN) is a precursor to invasive pancreatic adenocarcinoma which occurs almost exclusively in females in their 5th-7th decade. Currently the only option for MCN treatment and prevention of invasive pancreatic ductal adenocarcinoma (PDA) is oncologic resection. The clinical features of pancreatic MCN support the influence of sex hormones in the pathogenesis of the disease. Anti-hormonal therapy may therefore constitute an effective approach to treatment. Preliminary analyses from preclinical studies suggest that tamoxifen inhibits the spread and normal life cycle in MCN epithelial cells and fibroblasts. Investigators hypothesize that in humans, treatment with tamoxifen will lead to cyst regression or stabilization and may spare or delay the need for resection. Up to 15 participants not undergoing immediate resection will be enrolled and take tamoxifen orally for up to 24 weeks. The study will assess the feasibility of tamoxifen as a treatment for pancreatic MCN.