# Prostate specific membrane antigen PET avidity in a granular cell tumour of the left supraspinatus muscle: a case report

## TL;DR

A rare tumor in a man's shoulder showed high uptake in a prostate cancer imaging test, marking the first known case of this kind.

## Contribution

This is the first reported case of PSMA-PET avidity in a granular cell tumor.

## Key findings

- A PSMA-avid lesion in the left supraspinatus muscle was identified in a 60-year-old male.
- The lesion was confirmed as a granular cell tumor through biopsy.

## Abstract

Granular cell tumour is a rare, mostly benign, soft tissue, neuroectodermal tumour, most commonly seen in the skin and peripheral soft tissue. There are no publications to date of PSMA-PET avidity in a granular cell tumour. In this 60 year old male, staging PSMA-PET for a localized intermediate risk prostate cancer incidentally identified a PSMA-avid left supraspinatus lesion, which was subsequently biopsy-proven as a granular cell tumour. We present the first case of PSMA-avid granular cell tumour and add to the growing literature documenting PSMA-PET avidity in benign and malignant lesions apart from prostate cancer.