Paraneoplastic encephalitis associated with renal cell carcinoma

Area of Science:

• Neurology
• Oncology
• Immunology

Background:

• Paraneoplastic encephalitis is an autoimmune disorder associated with underlying tumors.
• Renal cell carcinoma (RCC) is a common kidney cancer with rare reported associations with paraneoplastic neurological syndromes.
• This study investigates the link between paraneoplastic encephalitis and RCC.

Purpose of the Study:

• To identify and characterize cases of paraneoplastic encephalitis associated with renal cell carcinoma.
• To explore the clinical presentation, diagnostic findings, and treatment outcomes in this patient cohort.

Main Methods:

• A prospective institutional cohort of autoimmune encephalitis patients with RCC was identified.
• Diagnostic criteria included operational autoimmune encephalitis criteria and simultaneous diagnosis of RCC with neurological manifestations.
• Case series analysis of three patients with encephalitis and RCC.

Main Results:

• Three patients with encephalitis and RCC were identified; two with clear cell RCC and one with chromophobe RCC.
• All patients presented with limbic encephalitis, exhibiting symptoms like cognitive decline, memory impairment, or seizures.
• Brain MRI revealed mesial temporal lobe T2 hyperintensities in two clear cell RCC patients; one chromophobe RCC patient had no remarkable findings.
• Early surgical intervention within one month of RCC onset correlated with a favorable treatment response.

Conclusions:

• Paraneoplastic encephalitis associated with RCC typically presents as limbic encephalitis.
• Treatment involving immunotherapy and tumor resection can be effective.
• RCC should be considered in the differential diagnosis of seronegative autoimmune encephalitis.