1305 A Genetically Rare Cancer Singled Out Just in Time: Pancreatic Neuroendocrine Tumor

Abstract

INTRODUCTION: Pancreatic neuroendocrine tumors (PNETs) are rare neoplasms that account for 1-2% of all pancreatic tumors. PNETs can manifest at any age, although, they occur commonly after the fourth decade of life. We herein report a patient diagnosed and managed for nonfunctioning PNET. It is important to acknowledge that these malignant tumors might have an insidious presentation. CASE DESCRIPTION/METHODS: 46-year-old male patient presented with unintentional 25-lb weight loss over 8 months with associated symptoms of weakness and decreased oral intake. Patient without major medical history and family history of gastric cancer, as well as, breast cancer. His physical examination was unremarkable. Initial laboratory workup including CBC, CMP, serum CA-19-9, IgG4, serum chromogranin A and serum neuron specific enolase were unremarkable. CT scan of the abdomen and pelvis, ordered for evaluation of unexplained weight loss, demonstrated a large lobulated mass replacing most of the pancreatic body and tail with loss of cobblestoning with several distinct peripancreatic soft tissue nodules. PET/CT revealed severe hypermetabolic lesion involving the body and tail of the pancreas. An endoscopic ultrasound with fine-needle biopsy of the pancreatic mass (3 cm × 2 cm) revealed a PNET. Immunohistochemical panel such as CK7, synaptophysin, and chromogranin were positive and CD34 as well as Pan-CK were non-contributory. Patient underwent a successful distal pancreatectomy, splenectomy, and removal of regional nodes without any complications. Histology confirmed a well differentiated PNET intermediate-grade (G2) with 2-20 mitosis/2 mm2, Ki-67 index of 3%-20%, and the tumor only involved the pancreas. A somatostatin receptor scintigraphy scan, using octreotide, was normal without evidence of any somatostatin avid lesions. The patient is currently under the care of the Gastroenterology and Hematology & Oncology service. DISCUSSION: PNETs are generally indolent malignancies and clinical manifestations can vary from abdominal pain, weight loss, anorexia, nausea, jaundice, palpable mass on physical exam or symptoms attributed to metastatic disease. No risk factors like smoking, diabetes, nor history of chronic pancreatitis were identified. It is of great importance to raise awareness of malignancy symptoms. This case demonstrates how a complete history and physical exam can lead to early identification of a curable malignancy, having a positive impact on the patient survival and quality of life.