38 Nonfunctioning Neuroendocrine Tumor of the Pancreas

Clinical Presentation

A 35-year-old woman presents with nonspecific abdominal pain.

Fig. 38.1 (A) Axial noncontrast CT image shows an exophytic lesion arising from the tail of the pancreas (arrow) with eccentric calcification. (B) The lesion shows early arterial enhancement and continues to stay enhanced on the (C) portal venous-phase image.

Radiologic Findings

Axial noncontrast computed tomography (CT) image (Fig. 38.1A) shows an exophytic lesion arising from the tail of the pancreas with eccentric calcification. The lesion shows early arterial and sustained enhancement on the contrast-enhanced series (Fig. 38.1B,C).

Diagnosis

Nonfunctioning neuroendocrine tumor of the pancreas

Differential Diagnosis

Ductal adenocarcinoma
Mucinous cystic tumor of the pancreas
Metastasis
Solid papillary epithelial neoplasm (SPEN)

Discussion

Background

Nonfunctioning neuroendocrine tumors of the pancreas are rare slow-growing tumors with a more indolent natural history compared with pancreatic adenocarcinoma. They constitute the majority of islet cell tumors of the pancreas and may account for up to 60% of all neuroendocrine tumors of the pancreas. Ninety percent of nonfunctioning tumors are malignant at presentation. Patients with nonfunctioning tumors do not have any symptoms from excessive hormone secretion by the tumor because the tumor does not release any hormones into the blood.