# Juvenile Rectal Polyp Exhibiting Osseous Metaplasia: A Case Report

## TL;DR

A 10-year-old boy had a rare case of a rectal polyp containing bone tissue, which was removed and found to be non-cancerous.

## Contribution

This is an extremely rare case of osseous metaplasia in a juvenile rectal polyp, adding to the limited literature on this phenomenon.

## Key findings

- A 2 cm pedunculated rectal polyp was removed and found to contain mature bony trabeculae.
- No dysplasia or cancerous changes were observed in the polyp tissue.
- Osseous metaplasia in juvenile polyps is rare and typically has no clinical significance.

## Abstract

A 10-year-old boy presented with painless rectal bleeding. No fever or weight loss was reported. He had no history of constipation. Ileocolonoscopy revealed a single 2 cm pedunculated polyp in the distal rectum, which was removed endoscopically. Histological examination demonstrated polypoid tissue with focal ulceration characterized by an inflamed lamina propria containing dilated, branched, and hyperplastic crypts. Higher-power microscopy revealed mature bony trabeculae within the lamina propria. No dysplasia was observed. Osseous metaplasia is generally regarded as clinically and prognostically insignificant and is typically an incidentalhistological finding. We report an extremely rare case of heterotopic bone formation in a juvenile rectal polyp and review recent literature on this phenomenon.