Epidermoid cyst arising from an intrapancreatic accessory spleen: a case report and a review of the literature.

Accessory spleen is estimated to occur in 1 in 10 people in the general population, usually in the tail of the pancreas. Epidermoid cysts arising from ectopic spleen tissue in the tail of the pancreas are a benign and extremely rare pathology. Only 27 cases with such pathology have been reported in the English literature. Differentiating this pathology from other pancreatic pathologies, especially in the presence of a history of recent cancer, is almost impossible. In this article, we report a 36-year-old African-American woman with a history of colon cancer and hemicolectomy who was incidentally found to have a cystic lesion in the tail of her pancreas during surveillance abdominal imaging. After a distal pancreatectomy, the lesion was diagnosed to be an epidermoid cyst in an intrapancreatic accessory spleen. This is the first report of such pathology in a patient with a recent history of cancer. We propose that this pathology be considered as a differential diagnosis when assessing patients with cystic lesions in their pancreas, even when they have a history of previous malignancies.