Atypical diffusion-restricted lesion in 5-Fluorouracil encephalopathy

Area of Science:

• Neuro-oncology
• Radiology
• Medical Chemistry

Background:

• 5-Fluorouracil (5-FU) is a common chemotherapy agent.
• Central nervous system (CNS) toxicity is a known side effect of 5-FU.
• Typical MR imaging findings of 5-FU encephalopathy involve deep cerebral white matter and corpus callosum lesions.

Observation:

• A gastric cancer patient presented with symptoms of CNS toxicity.
• MR imaging revealed atypical, reversible diffusion-restricted lesions.
• Lesions were observed in the bilateral basal ganglia, thalami, and parasagittal frontal cortex.

Findings:

• The observed lesions were atypical for 5-FU encephalopathy.
• Diffusion and T2-weighted imaging demonstrated the characteristic involvement of basal ganglia, thalami, and frontal cortex.
• The diffusion-restricted lesions showed reversibility, suggesting a dynamic process.

Implications:

• This case expands the understanding of 5-FU-induced neurotoxicity.
• It highlights the importance of considering atypical patterns in MR imaging for 5-FU encephalopathy.
• Recognizing reversible diffusion-restricted lesions may aid in timely diagnosis and management of chemotherapy-related CNS effects.