Posterior reversible encephalopathy syndrome mimicking brain metastases in a patient with metastatic transitional cell carcinoma.

Posterior reversible encephalopathy syndrome (PRES) has been described in the context of uncontrolled hypertension, eclampsia, renal disease and autoimmune conditions, or in patients treated with chemotherapy or immunosuppressive agents. In contrast, we report the occurrence of PRES in a patient with untreated metastatic transitional cell carcinoma. The case emphasizes important diagnostic challenges associated with atypical presentations without "typical" risk factors and the limitations of common diagnostic imaging modalities. It highlights the ability of nonmalignant conditions like PRES to mimic brain metastases and the importance of magnetic resonance imaging as a diagnostic tool. A high index of suspicion is warranted in atypical presentations, as prompt treatment is imperative to ensure full neurological recovery.