Endocrine Abstracts

Introduction: Insulinomas are pancreatic endocrine tumors originating in the beta cells, characterized by hypoglycemia resulting from insulin hypersecretion.

Objectives: To characterize the demography, the clinical features, imagiological findings and pathological evaluation of the cases of insulinomas identified in the previous 35 years at São João Hospital.

Methods: We retrospectively analyzed the cases diagnosed as insulinomas at São João Hospital in the period between January 1980 and December 2015.

Results: We identified 19 patients, 68% women, with a median age at onset of symptoms of 49 years. All patients presented neuroglycopenic symptoms and 79% also presented neurogenic symptoms. Whipple triad was present in all cases at the diagnosis and no case was associated with MEN1 syndrome. 17 patients (89%) had an abdominal CT performed, contributing to the location of the tumor in 12 patients. Abdominal magnetic resonance was performed and localized the tumor in five patients. Octreoscan was performed in three patients, detecting the tumor in only one case. Of the eight cases in whom abdominal ultrasound was performed, the tumor was localized in only two of them. Regarding the treatment, five patients were treated with diazoxide before surgery, and all patients were submitted to surgery. Enucleation of the tumor was performed in four cases and the remaining 15 were submitted to partial pancreatectomy. In one patient, the surgery did not remove the tumor and was unable to correct the fasting hypoglycemia, and so total pancreatectomy was performed. All tumors were solitary, with a median diameter of 1.8 cm. Ten tumors were located at the head of the pancreas, four at the body, four at the tail and one at the uncinate process. One tumor was associated with endogenous hyperinsulinism but negative insulin imunohistochemical evidence. There were no cases of lymphatic or vascular invasion. Surgical complications (fistula and infection) were observed in three patients. No patient presented evidence of recurring disease.

Conclusion: Our series of insulinomas, in agreement with the previous literature, has a predominance of female patients, with a peak age of onset between the third and fifth decade of life, and a predominance of neuroglycopenic symptoms.