Paraneoplastic Kelch-like protein 11 antibody-associated cerebellar and limbic encephalitis caused by metastatic "burned-out" seminoma - A scar(r)y phenomenon

Benedek Gyongyosi; Rita Magyar-Stang; Timea Takacs; Eszter Szekely; Zsolt Illes; Christine Nilsson; Tamas Gyorke; Peter Barsi; Daniel Juhasz; Balazs Banky; Daniel Bereczki; Jerome Honnorat; Bence Gunda

doi:10.1016/j.jneuroim.2023.578073

Paraneoplastic Kelch-like protein 11 antibody-associated cerebellar and limbic encephalitis caused by metastatic "burned-out" seminoma - A scar(r)y phenomenon

J Neuroimmunol. 2023 May 15:378:578073. doi: 10.1016/j.jneuroim.2023.578073. Epub 2023 Mar 23.

Authors

Affiliations

¹ Department of Pathology, Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary.
² Department of Neurology, Semmelweis University, Budapest, Hungary; János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary. Electronic address: [email protected].
³ Department of Neurology, Semmelweis University, Budapest, Hungary; János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary.
⁴ Department of Neurology, Odense University Hospital, Odense, Denmark.
⁵ Laboratory of Clinical Immunology, Odense University Hospital, Odense, Denmark.
⁶ Department of Nuclear Medicine, Medical Imaging Centre, Semmelweis University, Budapest, Hungary.
⁷ Department of Neuroradiology, Medical Imaging Centre, Semmelweis University, Budapest, Hungary.
⁸ Department of Urology, Semmelweis University, Budapest, Hungary.
⁹ Department of Surgery, Transplantation and Gastroenterology, Semmelweis University, Budapest, Hungary.
¹⁰ Department of Neurology, Semmelweis University, Budapest, Hungary.
¹¹ French Reference Center on Paraneoplastic Neurological Diseases and Autoimmune Encephalitis, Hospices Civils de Lyon, Université Claude Bernard, Lyon, France.

PMID: 36989702
DOI: 10.1016/j.jneuroim.2023.578073

Abstract

Introduction: The diagnosis of paraneoplastic neurologic syndromes is challenging when the primary tumor masquerades as scar tissue (i.e. "burned-out").

Methods: Case report.

Results: A 45-year-old male patient presented with progressive cerebellar symptoms and hearing loss. Initial screening for malignancy and extensive testing of paraneoplastic and autoimmune neuronal antibodies gave negative results. Repeated whole-body FDG-PET CT revealed a single paraaortic lymphadenopathy, metastasis of a regressed testicular seminoma. Anti-Kelch-like protein-11 (KLHL11) encephalitis was finally diagnosed.

Conclusion: Our case highlights the importance of continued efforts to find an often burned-out testicular cancer in patients with a highly unique clinical presentation of KLHL11 encephalitis.

Keywords: Burned-out seminoma; Cerebellar syndrome; Kelch-like protein 11 antibody; Limbic encephalitis; Paraneoplastic syndrome.

Publication types

Case Reports
Research Support, Non-U.S. Gov't

MeSH terms

Autoantibodies
Encephalitis* / complications
Encephalitis* / etiology
Humans
Limbic Encephalitis* / diagnostic imaging
Male
Middle Aged
Paraneoplastic Syndromes, Nervous System* / etiology
Seminoma* / complications
Testicular Neoplasms* / complications
Testicular Neoplasms* / diagnostic imaging

Substances

Autoantibodies
KLHL11 protein, human