Lenvatinib-Associated Posterior Reversible Encephalopathy Syndrome in Metastatic Clear Cell Renal Cell Carcinoma: A Case Report

A rare and severe neurological complication linked to the cancer drug lenvatinib has been documented in a case report published in Cureus, raising concerns about its safety profile in patients with advanced kidney cancer.

According to the report, a 65-year-old patient with metastatic clear cell renal cell carcinoma (RCC) developed posterior reversible encephalopathy syndrome (PRES) after starting treatment with lenvatinib, a tyrosine kinase inhibitor approved for several solid tumors. The patient experienced symptoms including severe headaches, altered mental status, and visual disturbances, which resolved after discontinuing the drug and receiving supportive care.

Lenvatinib is widely used to treat RCC, thyroid cancer, and hepatocellular carcinoma, but PRES—a condition characterized by reversible brain swelling and neurological dysfunction—remains an infrequent but serious adverse effect. The case highlights the need for vigilance in monitoring patients for neurological symptoms during treatment.

Why does this matter?
PRES is typically associated with hypertension, chemotherapy, or immunosuppressants, but its occurrence with targeted therapies like lenvatinib is less documented. The Cureus report notes that while PRES is generally reversible, early recognition and intervention are critical to preventing long-term complications.

The U.S. Food and Drug Administration (FDA) lists hypertension and reversible posterior leukoencephalopathy syndrome (RPLS, a related condition) as known risks of lenvatinib, but cases involving PRES specifically remain rare. The authors emphasize that clinicians should consider PRES in patients presenting with new neurological symptoms while on lenvatinib, even in the absence of severe hypertension.

What are the key details?

• Patient profile: A 65-year-old with metastatic clear cell RCC and no prior history of neurological disorders.
• Treatment timeline: Symptoms emerged within weeks of initiating lenvatinib (dose: 24 mg/day).
• Diagnosis: Confirmed via MRI showing characteristic posterior white-matter edema.
• Outcome: Symptoms resolved completely after drug discontinuation and blood pressure management.

How does this compare to prior findings?
While PRES has been linked to other tyrosine kinase inhibitors (e.g., sunitinib), the Cureus report is one of the first to document the complication specifically with lenvatinib in RCC patients. A 2023 review in Cancer Therapy noted that PRES occurs in less than 1% of cases across targeted therapies, but the risk may be underreported due to underdiagnosis.

The case underscores the importance of preemptive monitoring for neurological adverse events in patients receiving lenvatinib, particularly those with preexisting risk factors like uncontrolled hypertension or renal dysfunction. The authors recommend close collaboration between oncologists and neurologists in high-risk patients.

What remains uncertain?

• The exact mechanism by which lenvatinib triggers PRES is not fully understood.
• Whether genetic predisposition or concurrent medications play a role in susceptibility.
• Long-term neurological outcomes for patients who develop PRES during treatment.

For clinicians, the report serves as a reminder that even approved cancer therapies carry rare but serious risks. The FDA’s safety labeling for lenvatinib already advises monitoring for neurological symptoms, but this case adds to the growing body of evidence supporting proactive surveillance.

Sources: Case report in Cureus (2026); FDA labeling for lenvatinib; 2023 review in Cancer Therapy.