FDG-avid venous malformation could mimic malignancy on 18F-FDG PET/CT

Area of Science:

• Radiology
• Nuclear Medicine
• Vascular Imaging

Background:

• Positron Emission Tomography/Computed Tomography (PET/CT) using Fluorodeoxyglucose (FDG) is crucial for cancer surveillance.
• Melanoma patients require regular monitoring for recurrence and metastasis.
• FDG uptake can indicate metabolically active tissue, often associated with malignancy.

Observation:

• A 49-year-old melanoma patient presented with mildly FDG-avid pelvic soft tissue lesions on surveillance PET/CT.
• Magnetic Resonance Imaging (MRI) revealed these lesions as dilated vascular structures consistent with venous malformation.
• Follow-up PET/CT scans confirmed the stable, FDG-avid nature of these vascular malformations over two years.

Findings:

• Venous malformations can exhibit mild FDG avidity on PET/CT, mimicking malignant lesions.
• The lesions in this patient remained stable, showing no signs of malignancy or metastatic spread.
• Accurate differentiation between benign vascularity and neoplastic disease is critical.

Implications:

• FDG-avid vascular malformations may lead to misdiagnosis of malignancy in cancer surveillance.
• Unnecessary invasive procedures like biopsies could be avoided by considering vascular malformations in the differential diagnosis.
• Careful correlation with other imaging modalities like MRI is essential for accurate interpretation of PET/CT findings.