Endocrine Abstracts

Introduction

Glucagonoma is an extremely rare type of functional pancreatic neuroendocrine tumor that is characterized by distinctive clinical manifestations such as diabetes mellitus, weight loss, deep vein thrombosis, and necrolytic migratory erythema which represents the hallmark clinical sign of glucagonoma syndrome. Here, we report the case of a 53-year-old male patient who presented with high amilase and lipase levels. In further investigation a pancreatic tumor was determined and after pancreatic surgery it was diagnosed as glucagonoma.

Case

A 53-year-old male patient was examined routinely in cardiology. In the laboratory analysis, amilase and lipase were detected as above the upper limit of normal [amilase: 212 (Normal range: 30–118 U/l), lipase: 224 (Normal range: 12–53 U/l)]. He did not have any symptoms or signs associated with pancreatitis. Glycosylated A1c was 6.5%. In his past history he did not have diabetes mellitus. In the family history, he reported that his mother had diabetes. He referred to our outpatient clinic for prediabetes. Furtherly, 75 gr oral glucose tolerance test was performed. It was evaluated as impaired fasting glucose (0.min glucose: 115 mg/dl, 120.min glucose: 93 mg/dl). In the investigation of pancreatic enzyme abnormalities, abdominal ultrasound was performed. In the ultrasound, Grade 2 hepatosteatosis and a heterogenous weakly hypoechoic solid mass located in proximal pancreatic body which was 20x14.5 mm in diameter were detected. In abdominal MRI, a 21x16 mm mass located in posterior part of the pancreatic body which was mildly hyperintense in T2A and hypointense in T1A images was reported, and in contrasted images the tumor was found as prominent minimally according to parachyme, and had also diffusion restriction. For the investigation of neuroendocrine tumor, Ga-68 DOTA-PEPTIDE PET/CT was performed and it demonstrated a high pathologic Ga-68 enhancement in the pancreatic mass (SUVmax: 21.92). Then, the patient was operated. Distal pancreatectomy and splenectomy was performed. The histopathology was reported as grade 1 glucagonoma. Postoperatively, he had diabetes mellitus, he was under insulin treatment. His postoperative amilase, lipase values were normal. The postoperative glucagon value was 248 (normal range: 25–250 pg/ml).

Conclusion

Glucagonoma is a rare pancreatic neuroendocrine tumor. Most common presentation is the skin lesions. Our patient was diagnosed after investigation of biochemical abnormality. He presented atypically as he did not have most typical presentations like most patients in the literature.