Cystadenoma of the head of the pancreas is divided into plasmacytic cystadenoma and mucinous cystadenoma, and different types of cystadenoma are treated differently. Plasmacytoid cystadenoma is a completely benign tumor. If there are no uncomfortable symptoms and the tumor is small, it can be treated without treatment, as long as it is clinically observed. If there are painful symptoms or if it cannot be distinguished from mucinous cystadenoma, it should be surgically removed. Plasmacytoid cystadenoma of the head of the pancreas can be cured by pancreaticoduodenectomy. Mucinous cystadenoma, on the other hand, has a tendency to become malignant, so surgical resection is required once it is detected, and this surgical resection requires a large enough area to be removed, so that only tumor removal is not possible.