# Mucosal Schwann Cell Hamartoma of the Appendix: Expanding the Differential for Gastrointestinal Bleeding

## TL;DR

This paper reports a rare case of a benign tumor in the appendix causing gastrointestinal bleeding, highlighting its importance in differential diagnosis.

## Contribution

The paper expands the known locations of mucosal Schwann cell hamartomas to include the appendix.

## Key findings

- MSCH can cause symptomatic gastrointestinal bleeding.
- Histopathology and immunohistochemistry confirmed the diagnosis in the appendix.
- MSCH should be considered in the differential for unexplained gastrointestinal bleeding.

## Abstract

Mucosal Schwann cell hamartomas (MSCH) are rare benign tumors typically found in the colorectal region. We present the case of an 87-year-old man with a history of mucosa-associated lymphoid tissue lymphoma who developed symptomatic gastrointestinal bleeding due to an appendiceal MSCH. The patient's ongoing melena and anemia led to further evaluation. Subsequent colonoscopy revealed active bleeding from the appendiceal orifice with hemostasis achieved using epinephrine injection. A laparoscopic appendectomy confirmed MSCH through histopathology and immunohistochemical staining. Given its rarity, this case underscores the importance of considering MSCH in unexplained gastrointestinal bleeding and demonstrates its potential to be a symptomatically significant entity.