Pancreatic mucinous cystadenoma with serum CA 19-9 over 1,000,000 U/mL: a case report and review of the literature

The diagnosis of pancreatic cystic neoplasms has become more accurate recently. In some cases, however, doubt remains regarding the lesion's malignant potential. CA 19-9 has long been identified as a reliable biomarker in differentiating pancreatic benign and malignant lesions, especially in non-jaundiced patients. We report a case of a young female who presented with a mucinous lesion in the tail of the pancreas and a serum CA 19-9 over 1,000,000 U/mL. She was taken to surgery and had a distal pancreatectomy and splenectomy. Pathology reports showed only a mucinous cystadenoma. After 1 year of follow-up, her serum CA 19-9 was normal. Following that, the work-up in these lesions, the role of the biomarker in pancreatic adenocarcinoma and in the differentiation between benign and malignant lesions is discussed.