# Hijacked highway: A rare case of basal cell carcinoma encasing a cranio-peritoneal shunt

## TL;DR

A rare case of basal cell carcinoma involving a cranio-peritoneal shunt is reported, with no tumor spread through the device despite long-term follow-up.

## Contribution

This is the first documented case of BCC involving a cranio-peritoneal shunt, providing insights into tumor behavior around implanted devices.

## Key findings

- The patient developed typical BCC metastases (lung and bone) but no spread through the shunt.
- Long-term follow-up showed no cranial or peritoneal tumor dissemination.
- The case highlights the importance of multidisciplinary management for tumors involving implants.

## Abstract

Metastatic basal cell carcinomas (BCC) are rare. In event of metastasis, BCCs are most likely to spread to the lymph nodes, lungs, bones, and skin. BCC spreading along implanted devices has not been previously documented.

We report a case of a 48-year old man with a head and neck cutaneous BCC involving a cranio-peritoneal shunt, which holds the potential risk of tumor dissemination through this low-resistance pathway. He was followed up over his lifetime to determine if he developed cranial or peritoneal dissemination.

A multi-disciplinary team approach was undertaken, a joint case between plastic surgery and neurosurgery was required to secure the shunt and complete a wide local excision. Post-operatively, the patient had adjuvant radiotherapy. The metastatic spread in this case followed the usual pattern of BCC metastasis. The patient developed lung nodules and bone metastases, and died 23 months post-operatively. He did not develop cranial or peritoneal metastases. In this case, the involvement of the shunt did not alter the expected pattern of metastatic spread of BCC.

There is a limited number of case studies that describe implantable devices as a conduit for tumour dissemination.The risk of dissemination did not occur in this case. The long-term follow-up of this case contributes to the literature on decision making in the management of head and neck tumors involving shunts.