PRIMARY RETROPERITONEAL NEUROENDOCRINE TUMOR PRESENTING WITH SEGMENTAL SMALL INTESTINAL ISCHEMIA: CASE REPORT

Case Presentation An 89-year-old female patient presented with a three-month history of colicky abdominal pain, unmeasured weight loss, and anorexia. She visited the emergency department where a CT scan revealed segmental ileal wall thickening, prominent mesenteric vascular engorgement, and extensive adjacent lymphadenopathy. One week later, she developed intestinal ischemia in the ileal region and underwent exploratory laparotomy. The pathology report revealed a retroperitoneal tumor with morphological features consistent with a neoplasm of uncertain histogenesis affecting a fibroadipose tissue fragment. Surgical margins were free, with no angiolymphatic or perineural invasion. Metastasis was found in 2 of the 29 dissected lymph nodes. The immunohistochemical profile was consistent with a well-differentiated, low-grade (G1) neuroendocrine tumor, affecting fibroadipose tissue (positive for Chromogranin A, Synaptophysin, and Ki 67 positive in 2%).

Discussion The retroperitoneum is not a typical site for primary neuroendocrine tumors, with its presence commonly indicating metastatic disease originating from the gastrointestinal tract. These tumors are often discovered incidentally on routine exams, and they are oligossymptomatic in their early stages. When symptomatic, they often represent advanced disease with metastatic potential. They are classified into two subtypes based on their composition: neural, expressing neurofilaments (paragangliomas), and epithelial, expressing keratin (carcinoid). In elderly patients, the main cause of intestinal ischemia is thromboembolic events. Literature reports of neuroendocrine tumors causing intestinal ischemia are rare, with symptoms typically linked to carcinoid syndrome. A literature search revealed no reports of primary retroperitoneal neuroendocrine tumors presenting with intestinal ischemia. Most cases present with abdominal pain, palpable masses on physical examination, and symptoms due to compression of adjacent organs/structures.

Conclusion The diagnosis of a retroperitoneal neuroendocrine tumor presents challenges in case management, as symptoms may have atypical manifestations. Surgical resection may be necessary, or in specific cases, chemotherapy for undifferentiated or unresectable tumors.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
25 April 2025