Incidental Finding of a Neuroendocrine Tumor in the Distal Ileum: A Case Report

Abstract

Introduction: Neuroendocrine neoplasms (NENs) are rare, with an estimated annual incidence of 1.05 cases per 100,000 people. Over the past 30 years, their incidence has been on the rise, though the exact causes remain unclear.

Case Presentation: We report the case of a 56-year-old female patient with a history of treatment-resistant hypertension since 2022. She was referred to gastroenterology due to diffuse, colicky abdominal pain, accompanied by bloating and two loose bowel movements per day for the past two years. A colonoscopy with ileal intubation revealed a 15 mm sessile polypoid lesion in the distal ileum, located 5 cm from the ileocecal valve. An octreotide scan identified an intraluminal lesion in the distal ileum with somatostatin receptor overexpression, as well as an enlarged right ileocolic lymph node. The patient underwent laparoscopic surgery, which included a right hemicolectomy, distal ileum resection, and retroperitoneal lymphadenectomy. The final histopathological diagnosis confirmed a grade 2 ileal neuroendocrine tumor measuring 1.5 x 1 cm, extending into the muscularis propria without lymphovascular or perineural invasion. Surgical margins were tumor-free. To date, the patient has not required adjuvant therapy during follow-up.

Conclusion: This case highlights the importance of routine colonoscopy with ileal intubation, as it can facilitate the early detection of distal ileal neuroendocrine tumors, allowing for timely treatment and improved patient prognosis.