# Hepatocellular carcinoma arising from adenoma with ARID1A mutation in an adolescent patient with ATM germline mutation

## TL;DR

A 14-year-old boy with a rare liver tumor had both a germline ATM mutation and a somatic ARID1A mutation, suggesting a link between DNA repair issues and cancer development.

## Contribution

This case highlights a novel association between ATM germline mutation and ARID1A somatic mutation in pediatric liver cancer.

## Key findings

- A 14-year-old male had a hepatic adenoma with HCC containing both ATM and ARID1A mutations.
- The ATM germline mutation may have contributed to the ARID1A somatic mutation and cancer progression.
- The case emphasizes the need for genetic monitoring in patients with hepatic adenomas.

## Abstract

While hepatocellular carcinoma (HCC) is increasingly common in adults, it remains rare in children. Unlike adult HCC, which typically arises from cirrhosis, pediatric cases often occur without underlying liver disease. We report a 14-year-old male with a large hepatic adenoma containing multiple foci of HCC. Genetic testing revealed a germline ATM mutation and a somatic ARID1A mutation. We hypothesize that impaired DNA repair from the ATM mutation facilitated the ARID1A mutation, driving malignant transformation. This case underscores the importance of recognizing malignant potential in hepatic adenomas, utilizing appropriate imaging and pathology, and monitoring for associated cancers in genetically predisposed patients.