Incidental Discovery of an Appendiceal Neuroendocrine Tumour in a Young Adult: The Critical Roles of Histopathology, Oncological Safety and Risk-Adapted Management

Jia Chyi Tay, Woon Teen Sia, Neeroshini Soorianayanan, Yunrong Tan

Abstract


Appendiceal neuroendocrine tumours are rare, typically characterised by an indolent clinical course and often discovered incidentally during histopathological examination (HPE) following appendectomy for presumed acute appendicitis. Their identification has important implications for staging, risk stratification and further management. We present the case of a 22-year-old male who presented with right iliac fossa pain, fever, and vomiting. He underwent open appendectomy and the HPE revealed a well-differentiated (WHO Grade 1) neuroendocrine tumour at the tip of the appendix measuring 4 mm, with negative margins and no lymphovascular invasion. This case highlights the diagnostic challenge and reinforces the importance of sending all appendectomy specimens for routine HPE. The surgical approach, including maintaining a clean field and avoiding perforation, proved crucial for oncological safety. The tumour was staged as pT1 (American Joint Committee on Cancer 9th edition). Given the absence of high-risk features, further surgery, advanced imaging or biochemical surveillance was not indicated. A symptom-driven follow-up strategy was adopted, reflecting the ongoing debate on surveillance in such low-grade cases.


Keywords


Appendiceal neuroendocrine tumour; appendicectomy; NET; oncology

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References


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DOI: http://dx.doi.org/10.17576/JSA.2026.1602.05

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