# A Neuroendocrine Tumor of Unknown Primary Origin: A Case Report and Review of the Literature

## TL;DR

This paper presents a case of a rare tumor with an unknown origin and discusses the challenges in diagnosing and treating such tumors.

## Contribution

The paper contributes a detailed case report and review of diagnostic and therapeutic approaches for neuroendocrine tumors of unknown primary origin.

## Key findings

- NETs of unknown primary origin pose diagnostic and therapeutic challenges.
- A multidisciplinary approach is essential for diagnosis and treatment.
- Biochemical, histopathological, and imaging methods are crucial in workup.

## Abstract

Neuroendocrine tumors (NETs) are uncommon malignancies that develop from neuroendocrine cells which most commonly occur in the GI tract, lung, and pancreas. Treatment courses for these tumors are largely dictated by the primary origin site, which can present diagnostic and therapeutic challenges in NETs of unknown primary origin. Herein, we present a case of an NET of unknown primary origin with significant liver metastases. Our aim is to highlight the key components of the workup of NETs of unknown primary origin and detail the biochemical, histopathological, and imaging modalities as recommended by current literature. We highlight the importance of a multidisciplinary approach to both diagnosis and treatment of these patients as well as touch upon therapeutic options.