Paraneoplastic limbic encephalitis in a patient with extensive disease small-cell lung cancer

Paraneoplastic neurological syndromes of small cell lung cancer

Purpose

This article reviews the relevant literature on paraneoplastic neurological syndromes of small cell lung cancer and discusses the clinical presentation, pathophysiology, and diagnosis of these syndromes. It also includes a summary of the current treatment options for the management of them.

Views

Paraneoplastic syndromes are a group of signs and symptoms that develop due to cancer in a remote site, mainly triggered by an autoantibody produced by the tissues involved or lymphocytes during anti-cancer defense. Among the cancers associated with paraneoplastic syndromes, lung cancers are the most common type, with small cell lung cancer being the most common subtype. The most common antibody associated with paraneoplastic syndromes is anti-Hu. Neurological and neuroendocrine syndromes comprise the majority of small cell lung cancer-related paraneoplastic syndromes. Classical paraneoplastic neurological syndromes include inappropriate antidiuretic hormone secretion, Cushing's syndrome, myasthenia gravis, Lambert-Eaton myasthenic syndrome, limbic encephalitis, paraneoplastic cerebellar degeneration, opsoclonus myoclonus ataxia, sensory neuropathy, and chorea.

Conclusions

Antibodies mediate paraneoplastic syndromes, and antibody detection is a crucial part of diagnosing these entities. Managing the underlying tumor is the best treatment approach for most paraneoplastic syndromes. Therefore, early diagnosis of small cell lung cancer may significantly improve the prognosis of paraneoplastic syndromes associated with it.

18 F-FDG PET and MRI Evaluation of Paraneoplastic Limbic Encephalitis

ABSTRACT

Autoimmune limbic encephalitis (paraneoplastic or nonparaneoplastic) is a rare condition involving autoantibodies against intracellular or cell-surface proteins of neurons. Patients typically present with acute and progressive neuropsychiatric symptoms. Although the criterion standard for diagnosis remains detection of autoantibodies in cerebrospinal fluid, there are characteristic imaging features that can aid in diagnosis, notably abnormalities in the bilateral medial temporal lobes on imaging, particularly with nuclear imaging. Here, we present 18 F-FDG PET findings of paraneoplastic limbic encephalitis in a 65-year-old man.