Do Not Miss MEN 1 Screening When Patients Are Newly Diagnosed With Pancreatic Neuroendocrine Tumor

Abstract

Abstract Background: Multiple endocrine neoplasia type 1(MEN 1) is a rare genetic disorder characterized by the combined occurrence of parathyroid, pituitary, and duodeno-pancreatic neuroendocrine tumors (NETs) along with other characteristic tumors. Here, we present a patient with history of pancreatic NET who presented 2 years after her initial diagnosis with primary hyperparathyroidism and prolactinoma, consistent with MEN 1. Case Report: A 60-year-old African American woman was admitted to our hospital with nausea, vomiting and headache for a week. On presentation, she was found to be hypotensive and tachycardic, both responded to IV fluids. Workup for infectious etiology came back negative. Her physical exam was benign except for dry oral mucosa, dry skin and epigastric tenderness. Laboratory evaluation showed serum calcium 11.8 mg/dL (8.4 - 10.2 mg/dL), which prompted further work up. Her PTH level was 1,079 pg/ml (8.5 - 72.5 pg/ml), Phosphorus 2.1 mg/dL (2.3 - 4.7 mg/dL), and 25 Hydroxy Vitamin D 10.2 ng/ml (7.4 - 44.0 ng/ml). Additional history and review of her records revealed she was hospitalized 2 years earlier with nausea, vomiting and abdominal pain. Then she was found to have esophageal and gastric ulcers on EGD. Endoscopic ultrasound revealed an 8 mm hypoechoic lesion in the body of pancreas found to be a pancreatic NET on biopsy. She had elevated gastrin level of 470 pg/ml (0 - 115 pg/ml) and was diagnosed with a gastrinoma. She was discharged on a PPI and was lost to follow up. Patient had no significant family history. Given her past history and current presentation, we assessed her pituitary hormonal function which was unremarkable except for prolactin level of >1,000 ng/ml (post-menopausal 1.8 - 20.3 ng/ml). Pituitary MRI showed a 1.8 cm macroadenoma. The optic nerve and optic chiasm were normal. Based on her clinical presentation and radiologic findings, she was diagnosed with MEN 1. Her Calcium level trended down with IV hydration, and her presenting symptoms resolved. She was started on bromocriptine, pantoprazole and vitamin D and was discharged with out-patient appointments scheduled with gastroenterology and endocrinology clinics. Conclusion: This case highlights the importance of having a high index of suspicion to prompt screening for MEN 1 in patients newly diagnosed with a pancreatic NET. Early diagnosis and timely treatment of the associated disease conditions in MEN 1 can prevent significant morbidity and mortality associated with these conditions.