Neuroendocrine Tumor Case Study

INTRODUCTION

Neuroendocrine tumors (NETs) encompass diverse types of tumors arising from neuroendocrine (enterochromaffin) cells found throughout the body. While NETs often have a relatively indolent course, there is a propensity for metastasis to the liver producing the classic carcinoid syndrome of diarrhea and flushing. Metastasis to other sites such as the peritoneum and mesentery is also common {Woodside 2004; Akerstrom 2005} however primary mesenteric NET is rare. We present a 64 year-old man with mesenteric NET without any other primary site.

CASE PRESENTATION

A 64 year-old man with a past medical history of mechanical aortic valve replacement on Coumadin, coronary artery disease with a history of coronary artery bypass graft, permanent

Broadly, NETs are classified based on tumor differentiation into well differentiated (low and intermediate grade) and poorly differentiated (high grade) NET. Grading addresses aggressiveness of the tumor with Grade 1, 2 and 3 representing low, intermediate and poorly differentiated tumors respectively {Rindi 2007}. Well differentiated NETs are generally rare {Klimstra 2010}. Carcinoid tumors are well differentiated NETs arising from the digestive tract, commonly the small intestine {Modlin 2003}. Other carcinoid tumor origins include the lungs, thymus, ovaries and kidneys.

Primary mesenteric carcinoid tumors are extremely rare {Karahan 2006}. Park et al. reported a case of a solitary 8 cm mesenteric carcinoid tumor in a 73 year-old woman after a meticulous search for tumors at other sites {Park 2013}. Yamanuha reported mesenteric tumor in a 52 year old with a partially calcified lobulated mass in the mesentery with smaller nodes in adjacent mesentery also without tumor activity elsewhere after imaging, colonoscopy and direct visualization at surgery {Yamanuha 2009}. Karahan et al. also reported a 2 cm primary mesenteric tumor with an area of calcification {Karahan