# Genetic Complexity in Recurrent Basal Cell Carcinoma: A MUTYH Variant Case Report

## TL;DR

A patient with recurring skin cancer had a rare MUTYH gene mutation, suggesting a new link between this mutation and cancer risk.

## Contribution

Identifies a novel association between MUTYH monoallelic mutations and recurrent basal cell carcinoma.

## Key findings

- A patient with recurrent basal cell carcinomas had a pathogenic MUTYH mutation.
- The case suggests MUTYH mutations may be linked to both skin and colorectal cancer risks.
- Early screening is recommended for patients with MUTYH mutations to detect cancer risks.

## Abstract

The MYUTH gene plays a critical role in preserving the integrity of the human genome, with mutations being identified in several different cancer diagnoses. It serves its purpose by encoding a DNA glycosylase enzyme responsible for preventing oxidative damage through the excision of adenine that is incorrectly paired with guanine or cytosine. Mutations of the MUTYH gene have been most frequently associated with MUTYH-associated polyposis (MAP) and colorectal cancer. Biallelic mutations of the MUTYH gene are implicated in MAP, and carriers of this mutation have an increased lifetime risk of developing colorectal cancer of 43% to 100%, depending on the appropriate screening and surveillance steps taken. This case describes a patient with recurrent basal cell carcinomas (BCC) and subsequent genetic testing that revealed a pathogenic monoallelic mutation of the MUTYH gene, as well as the interventions that were subsequently performed. It highlights a potentially new patient population that would benefit from early screening to assess the risk of developing colorectal cancers as well as BCC.