# Unmasking Carcinoid Syndrome in a Chronic Obstructive Pulmonary Disease (COPD) Patient: A Rare Presentation with Wheezing and Angioedema

## TL;DR

A COPD patient presented with unexplained symptoms that were later found to be due to carcinoid syndrome, highlighting the importance of considering this rare condition in similar cases.

## Contribution

This case report highlights the rare presentation of carcinoid syndrome in a COPD patient and emphasizes the importance of timely diagnosis.

## Key findings

- The patient had elevated levels of serum serotonin, chromogranin A, and 5-HIAA, indicating carcinoid syndrome.
- Imaging and biopsy confirmed a well-differentiated grade 1 neuroendocrine tumor with liver metastases.
- Treatment with lanreotide led to symptom resolution, showing the effectiveness of targeted therapy.

## Abstract

Carcinoid syndrome is a rare condition resulting from neuroendocrine tumors (NETs) that secrete vasoactive substances like serotonin. This report describes the case of a 61-year-old man with a history of chronic obstructive pulmonary disease (COPD) and hypertension who presented with new-onset angioedema, loss of consciousness, and a fall. He had been treated for COPD exacerbations during ER visits without improvement and was unaware of a prior mesenteric carcinoid tumor diagnosis from 2012. The next emergency evaluation revealed significant airway and facial edema necessitating intubation. Imaging and biopsy identified a well-differentiated grade 1 NET with extensive liver metastases. Laboratory tests showed elevated levels of serum serotonin, chromogranin A, and 24-hour urine 5-hydroxyindoleacetic acid (5-HIAA). Post-discharge, a PET scan confirmed metastatic lesions primarily in the liver and small bowel, with an unresectable mesenteric mass. The patient was treated with lanreotide and became symptom-free. This case underscores the need to consider carcinoid syndrome in patients with COPD presenting with unexplained respiratory symptoms, as timely diagnosis and treatment can significantly enhance patient outcomes.