Endocrine Abstracts

Introduction and objective: Neuroendocrine tumors (NETs) are a rare kind of tumor that can have various locations. Pancreatic location is the most common after the gastrointestinal tract. The aim of this report is to study the characteristics of neuroendocrine tumors located in the pancreatic gland (pNETs) at diagnosis.

Material and methods: Descriptive and retrospective study about 22 patients diagnosed of pNET during the period 1993–2010 in our hospital. Data regarding demographic, clinical, analytical, anatomopathological and diagnostic variables were collected. Statistical analysis was performed using SPSS 16.0, results are expressed as mean±S.D.

Results: Twenty-two patients (64% men) with a mean age at diagnosis of 43.0±14.1 years were studied. Six (27.3%) patients had type 1 multiple endocrine neoplasia. Fifteen (68.2%) presented typical clinical syndrome of their pNET and pancreatic tail was the most common location (54.5%) followed by head (40.9%). The mean tumor size was of 3.9±2.1 cm. Tumors were diagnosed more frequently by imaging techniques (CT: 54.5%, MR: 31.8% and others: 36.3%), and surgery was required only in one case.

Anatomopathologically, the tumors were classified as insulinomas (40.9%), non-secreting pancreatic tumor (36.4%), gastrinoma (9.1%), and glucagonoma, somatostatinoma and ectopic secretion pancreatic tumor (4.5%, each one). Inmunohistochemical markers resulted positive for: insulin (40.9%), glucagon (16.7%), gastrin and progesterone (9.2%) and somatostatin and PTHrp (4.5%). Ki67% was <2% in 16.7% of patients, between 2 and 15% in 50.0% and >15% in 33.3%.

Fourteen (63.6%) had metastases at diagnosis, all of them hepatic.

Conclusions: According to our experience, most pancreatic neuroendocrine tumors produce typical symptoms with a high proliferative index observed in the anatomopathological study. They are usually detected in an advanced metastatic stage, being the liver the most common affected gland. This delay in the diagnosis might be due to a low suspicion of these kinds of tumors.