Search

Objective: This article reviews the clinical presentations, neural antibody associations, and oncologic accompaniments of paraneoplastic neurologic syndromes and neurologic autoimmunity in the context of immune checkpoint inhibitor (ICI) cancer immunotherapy., Latest Developments: Neural antibody discovery has improved the diagnosis of paraneoplastic neurologic syndromes. Neural antibodies also delineate the underlying disease pathophysiology and thus inform outcomes and treatments. Neural antibodies specific for extracellular proteins have pathogenic potential, whereas antibodies specific for intracellular targets are biomarkers of a cytotoxic T-cell immune response. A recent update in paraneoplastic neurologic syndrome criteria suggests high- and intermediate-risk phenotypes as well as neural antibodies to improve diagnostic accuracy in patients with paraneoplastic neurologic syndromes; a score was created based on this categorization. The introduction of ICI cancer immunotherapy has led to an increase in cancer-related neurologic autoimmunity with distinct clinical phenotypes., Essential Points: Paraneoplastic neurologic syndromes reflect an ongoing immunologic response to cancer mediated by effector T cells or antibodies. Paraneoplastic neurologic syndromes can present with manifestations at any level of the neuraxis, and neural antibodies aid diagnosis, focus cancer screening, and inform prognosis and therapy. In patients with high clinical suspicion of a paraneoplastic neurologic syndrome, cancer screening and treatment should be undertaken, regardless of the presence of a neural antibody. ICI therapy has led to immune-mediated neurologic complications. Recognition and treatment lead to improved outcomes., (Copyright © 2024 American Academy of Neurology.)

Background and Objectives: Dysautonomia has been associated with paraneoplastic neurological syndrome (PNS)-related mortality in anti-Hu PNS, but its frequency and spectrum remain ill-defined. We describe anti-Hu patients with dysautonomia, estimate its frequency, and compare them to patients without dysautonomia., Methods: Patients with anti-Hu antibodies diagnosed in the study centre (1990-2022) were retrospectively reviewed; those with autonomic signs and symptoms were identified., Results: Among 477 anti-Hu patients, 126 (26%) had dysautonomia (the only PNS manifestation in 7/126, 6%); gastrointestinal (82/126, 65%), cardiovascular (64/126, 51%), urogenital (24/126, 19%), pupillomotor/secretomotor (each, 11/126, 9%), and central hypoventilation (10/126, 8%). Patients with isolated CNS involvement less frequently had gastrointestinal dysautonomia than those with peripheral (alone or combined with CNS) involvement (7/23, 30% vs. 31/44, 70% vs. 37/52, 71%; P = 0.002); while more frequently central hypoventilation (7/23, 30% vs. 1/44, 2.3% vs. 2/52, 4%; P < 0.001) and/or cardiovascular alterations (18/23, 78% vs. 20/44, 45% vs. 26/52, 50%; P = 0.055). Median [95% CI] overall survival was not significantly different between patients with (37 [17; 91] months) or without dysautonomia (28 [22; 39] months; P = 0.78). Cardiovascular dysautonomia (HR: 1.57, 95% CI [1.05; 2.36]; P = 0.030) and central hypoventilation (HR: 3.51, 95% CI [1.54; 8.01]; P = 0.003) were associated with a higher risk of death, and secretomotor dysautonomia a lower risk (HR: 0.28, 95% CI [0.09; 0.89]; P = 0.032). Patients with cardiovascular dysautonomia dying ≤ 1 year from clinical onset had severe CNS (21/27, 78%), frequently brainstem (13/27, 48%), involvement., Discussion: Anti-Hu PNS dysautonomia is rarely isolated, frequently gastrointestinal, cardiovascular and urogenital. CNS dysfunction, particularly brainstem, associates with lethal cardiovascular alterations and central hypoventilation, while peripheral involvement preferentially associates with gastrointestinal or secretomotor dysautonomia, being the latest more indolent., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Objective: This study aimed to explore the clinical characteristics and temporal disease course of patients with autoimmune encephalitis (AE) and paraneoplastic neurological syndrome (PNS) in Sweden., Methods: Thirty-seven antibody-positive AE and PNS cases were identified in the Healthcare region Mid Sweden between 2015 and 2019. Clinical data were collected through a retrospective review of electronic health records. Patients were divided into three subgroups based on antibody type: neuronal surface antibodies (NSAbs), onconeural antibodies, and anti-GAD65 antibodies., Results: Nineteen patients had NSAbs, 11 onconeural antibodies, and seven anti-GAD65 antibodies. Anti-LGI1 and anti-NMDAR were the most frequently detected NSAbs, with anti-NMDAR cases having an older-than-expected age distribution (median age 40, range 17-72). Only 11 of 32 (30%) of patients had findings suggesting encephalitis on initial MRI, but 28 of 31 (90%) had pathological findings on initial cerebrospinal fluid analysis. All patients but one had abnormal EEG findings. Median time to immunotherapy was comparable among the three subgroups, whereas patients with anti-LGI1, anti-CASPR2, and anti-IgLON5 had an eightfold longer time to immunotherapy than anti-NMDAR and anti-GABA-B (p = .0016). There was a seasonal variation in onset for patients with non-tumor-related NSAbs and anti-GAD65 antibodies, with most patients (72%) falling ill in spring or summer., Conclusion: Swedish patients with AE and PNS had similar clinical characteristics as previously described cohorts from other geographical regions except for anti-NMDAR encephalitis, with older onset than expected. The onset of non-tumor-related AE occurred predominantly in the warm seasons, and AE with a more insidious onset was associated with delayed treatment initiation., (© 2024 The Authors. Brain and Behavior published by Wiley Periodicals LLC.)

Objective: Cochleovestibulopathy is a distinguishable paraneoplastic phenotype. In this study, we evaluate clinical presentation, serological/cancer associations and outcomes of paraneoplastic cochleovestibulopathy., Methods: Retrospective chart review of patients with hearing impairment and/or vestibulopathy who underwent serological evaluations for paraneoplastic antibodies between January 2007 and February 2021 was performed., Results: Twenty-six patients were identified (men, n=23; median age, 45 years, range: 28-70). Biomarkers detected included: KLHL11-IgG‌ ‌(n=20,‌ ‌77% (coexisting LUZP4-IgG, n=8)),‌ ‌‌ANNA1-IgG‌ ‌ ‌(n=3,‌ ‌12%),‌ ‌amphiphysin-IgG‌‌ ‌(n=2,‌ ‌8%)‌ ‌and‌ ‌LUZP4-IgG‌‌ ‌(n=1,‌ ‌4%). Most common neoplastic association was ‌testicular‌/‌extra-testicular‌ ‌seminoma‌ ‌ (n=13,‌ ‌50%).‌‌ Hearing‌ impairment (bilateral, 62%) was ‌present‌ ‌in‌ ‌all‌ ‌patients.‌ ‌Fifteen patients (58%) had cochleovestibular dysfunction as their initial presentation before rhombencephalitis/encephalomyelitis manifestations (hearing loss, four; acute vertigo, eight; both, three). ‌Brain‌ ‌MRI‌ ‌demonstrated‌ ‌internal‌ ‌auditory‌ ‌canal‌ ‌enhancement‌ ‌in‌ ‌four ‌patients.‌ Audiometry commonly revealed severe-profound bilateral sensorineural hearing loss. Most patients ‌had‌ a refractory course ‌despite‌ ‌immunotherapy‌ ‌and/or‌ ‌cancer‌ ‌treatment‌., Conclusion: Cochleovestibulopathy commonly presents with rapidly progressive bilateral hearing loss and/or acute vertigo. However, in some patients, these symptoms present along with or following brainstem/cerebellar manifestations. KLHL11-IgG and seminoma are the most common serological and cancer associations, respectively. Recognition of this phenotype may aid in earlier diagnosis of paraneoplastic autoimmunity and associated cancer., Competing Interests: Competing interests: MBH, SDZE, AM and MJM have no competing interests to disclose. DD and SJP have a patent pending for leucine zipper 4 (LUZP4) and kelch-like protein 11 (KLHL11) as a marker for neurological autoimmunity and testicular germ cell tumours., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

A 75-year-old man was hospitalised for bronchoscopy with biopsy due to a suspicious pulmonary mass at chest tomography. He had significant dyspnoea, constipation, nausea, vomiting, anorexia and a 33% loss of weight in the past 3 months. Biopsy revealed a pulmonary squamous cell carcinoma, which was inoperable. Tramadol used at home for 3 months was replaced by morphine on admission. The patient remained constipated despite prokinetics and laxatives, leading to the diagnostic hypothesis of paraneoplastic motility disorder and opioid-induced constipation. Abdominal tomography ruled out the possibility of mechanical obstruction. As complications, the patient presented superior vena cava syndrome and opioid (morphine) intoxication. The patient died a few days later. The management of this case highlights the importance of multidisciplinary care and the challenges of palliative oncology care. Paraneoplastic motility disorder must always be considered among the mechanisms of intestinal dysfunction in patients with advanced oncological disease., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Patients with craniopharyngioma are susceptible to autonomic dysfunction as a result of hypothalamic damage. We evaluated indices of heart rate variability (HRV) in patients with childhood-onset craniopharyngioma to investigate autonomic function and its relationship with components of the metabolic syndrome (MetS). This cross-sectional, case-only study included 53 patients (10-30 years of age). We measured the standard deviation of all normal R-R intervals (SDNN) and total power indicating overall HRV, the root-mean square of the difference of successive R-R intervals (RMSSD) and high frequency indicating parasympathetic modulation, and low frequency. These indices were compared according to the presence of the MetS. During the mean 10.8 years of follow-up, 25% of patients were diagnosed with the MetS. Patients with the MetS showed significantly lower levels of SDNN (29.0 vs. 40.6 ms), total power (416.1 vs. 1129.6 ms 2 ), RMSSD (20.1 vs. 34.5 ms), high frequency (94.7 vs. 338.5 ms 2 ), and low frequency (94.5 vs. 289.4 ms 2 ) than those without (p <0.05, for all). Individual components of the MetS including insulin resistance, serum triglycerides levels, and systolic blood pressure were inversely associated with SDNN, total power, RMSSD and high frequency. Higher overall variability and parasympathetic modulation were related to decreased odds ratios for having the MetS (OR 0.91, p=0.029 for SDNN; OR 0.91, p=0.032 for total power). In conclusion, autonomic dysfunction, as evidenced by reduced HRV indices, is associated with increased cardiometabolic risk in patients with childhood-onset craniopharyngioma., Competing Interests: The authors declare that they have no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Paraneoplastic encephalitis encompasses a diverse spectrum of neurological disorders associated with a variety of pediatric tumor types., Methods: We describe a seven-year-old boy with paraneoplastic necrotizing encephalitis associated with precursor B-cell acute lymphoblastic leukemia., Results: The initial presentation involved acute-onset upper extremity weakness, seizure-like activity, and agitation. Extensive evaluation revealed pancytopenia, elevated protein in the cerebrospinal fluid, and normal magnetic resonance imaging (MRI) consistent with a clinical diagnosis of encephalitis of presumed viral etiology. He was treated with antimicrobials and intravenous immunoglobulin and returned to his neurological baseline before discharge. One month later, he was diagnosed with precursor B-cell acute lymphoblastic leukemia. Before chemotherapy initiation, he again became encephalopathic. Repeat cerebrospinal fluid evaluation showed elevated protein, and MRI revealed findings consistent with diffuse necrotizing encephalitis. He received standard chemotherapy as well as immunotherapy with intravenous immunoglobulin and plasmapheresis, with resolution of MRI abnormalities and improvement in neurological status. At six years postpresentation, he is in remission for acute lymphoblastic leukemia, without significant neurocognitive deficits and mild right spastic hemiparesis., Conclusion: This is the first report of paraneoplastic encephalitis associated with pediatric leukemia. A hematologic malignancy should be considered in the differential diagnosis of paraneoplastic encephalitis., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Immune response against neuronal and glial cell surface and cytosolic antigens is an important cause of encephalitis. It may be triggered by activation of the immune system in response to an infection (para-infectious), cancer (paraneoplastic), or due to a patient's tendency toward autoimmunity. Antibodies directed toward neuronal cell surface antigens are directly pathogenic, whereas antibodies with intracellular targets may become pathogenic if the antigen is transiently exposed to the cell surface or via activation of cytotoxic T cells. Immune-mediated encephalitis is well recognized and may require intensive care due to status epilepticus, need for invasive ventilation, or dysautonomia. Patients with immune-mediated encephalitis may become critically ill and display clinically complex and challenging to treat movement disorders in over 80% of the cases (Zhang et al. in Neurocrit Care 29(2):264-272, 2018). Treatment options include immunotherapy and symptomatic agents affecting dopamine or acetylcholine neurotransmission. There has been no prior published guidance for management of these movement disorders for the intensivist. Herein, we discuss the immune-mediated encephalitis most likely to cause critical illness, clinical features and mechanisms of movement disorders and propose a management algorithm.

Background: The identification of autoantibodies directed against neuronal antigens has led to the recognition of a wide spectrum of neurological autoimmune disorders (NAD). With timely recognition and treatment, many patients with NAD see rapid improvement. Symptoms associated with NAD can be diverse and are determined by the regions of the nervous system affected. In addition to neurological symptoms, a number of these disorders present with prominent gastrointestinal (GI) manifestations such as nausea, diarrhea, weight loss, and gastroparesis prompting an initial evaluation by gastroenterologists., Purpose: This review provides a general overview of autoantibodies within the nervous system, focusing on three scenarios in which nervous system autoimmunity may initially present with gut symptoms. A general approach to evaluation and treatment, including antibody testing, will be reviewed., (© 2019 John Wiley & Sons Ltd.)

Objective: To present clinical, radiological, and pathological features of a cohort of patients with motor neuron involvement in association with anti-Ma2 antibodies (Ma2-Ab)., Methods: Retrospective case-series of patients with definite paraneoplastic neurological syndrome (PNS) and Ma2-Ab, and cases identified from a review of the literature., Results: Among 33 Ma2-Ab patients referred between 2002 and 2016, we retrospectively identified three patients (9.1%) with a motor neuron syndrome (MNS). Seven additional cases were retrieved among the 75 Ma2-patients reported in the literature (9.3%). A total of ten patients are, therefore, described herein. MNS was evident as combined upper and lower MNS in four patients, isolated upper MNS in two, and isolated lower MNS in one; three patients were diagnosed with myeloradiculopathy. The most common MNS signs/symptoms were: hyperreflexia (80%), proximal weakness (60%), proximal upper-limb fasciculations (50%), head drop (40%), and dysarthria/dysphagia (30%). Brain MRI abnormalities included bilateral pyramidal tract T2-weighted/FLAIR hyperintensities (three patients). Spine MRI found bilateral, symmetric, T2-weighted signal abnormalities in the anterior horn in two patients. CSF examination was abnormal in nine patients. Cancer was found in seven patients (four testicular, two lung, and one mesothelioma). Eight patients underwent first-line immunotherapy. Second-line immunotherapy was adopted in all our patients and in none of those identified in the literature. Motor improvement was observed in 33% of our patients, and 20% in the literature series., Conclusions: Motor neuron involvement could complicate Ma2-Ab-associated PNS in almost 10% of patients and must be carefully studied to adapt treatment. This disorder differs from amyotrophic lateral sclerosis.

Objective: To report the clinical features and long-term outcome of 22 newly diagnosed paraneoplastic patients with GABA B receptor antibodies (GABA B R-Abs)., Methods: Retrospective clinical study of CSF-confirmed cases of GABA B R-Abs encephalitis., Results: We identified 22 patients (4 female) with GABA B R-Abs, with a median age of 64 years (range 55-85). All were paraneoplastic: 20 small-cell lung cancer, one malignant thymoma, and one uncharacterized lung mass. The most frequent first symptom was the isolated recurrent seizures without cognitive inter-ictal impairment in 17 patients (77%). In the other, three presented the first behavioral disorders and two presented de novo status epilepticus (SE). After a median delay of 10 days (range 1-30), the recurrent seizures' phase was followed by an encephalitic phase characterized by confusion in 100% of cases and SE in 81% (n = 17), with 53% (n = 9) non-convulsive SE. Dysautonomic episodes were frequent (36%, n = 8, bradycardia and central apnea) and killed three patients. CSF study was abnormal in 95% of the cases (n = 21). At the encephalitic phase, MRI showed a temporal FLAIR hypersignal in 73% (n = 16) of the cases. First-line immunotherapy was initiated after a median delay of 26 days (range 6-65) from disease onset, and a partial response was observed in 10 out of 20 patients (50%). There was no complete response. Two years after onset, a massive anterograde amnesia affected all still alive patients. Nine patients died from cancer progression (median survival: 1.2 years)., Conclusion: Paraneoplastic GABA B R-Abs encephalitis is characterized by a stereotype presentation with an epilepsy phase before an encephalitic phase with dysautonomia. The functional prognosis is poor.

Objective: To explore the diversity and clinical features of anti-glutamate decarboxylase (GAD) antibody-associated neurological diseases., Methods: Clinical data of a series of 5 patients positive for anti-GAD antibodies were retrospectively analyzed., Results: All 5 patients were female, with a median age of 41.5 years (range 19-60 years). Their neurological symptoms included stiff-person syndrome (SPS), encephalitis, myelitis, cramp, visual loss, and paresthesia. Three patients (60%) were diagnosed with tumors, 2 cases of thymic tumor and 1 of breast cancer. On immunohistochemistry for tumor pathology, expression of GAD65 was found only in 1 patient. Four patients (80%) had abnormal brain MRI findings. All patients received immunotherapy and improved significantly after treatment, but 4 (80%) then experienced a relapse., Conclusions: Neurological manifestations in anti-GAD-positive patients are diverse and include SPS, encephalitis, myelitis, cramp, visual loss, and paresthesia., (© 2019 S. Karger AG, Basel.)

Parkinsonism can be manifested and complicate either systemic or organ-specific autoimmune diseases. Even though it is a rare co-morbidity, it merits attention from clinicians as it affects the quality of life of patients. In systemic autoimmune diseases such as systemic lupus erythematosus, antiphospholipid syndrome and Sjogren's syndrome reported cases of parkinsonism are attributed to the underlying disease and its mechanisms, whether this is brain vasculitis or immune complexes. Regarding antibody-mediated autoimmune neurological disorders, parkinsonism is, in most cases, a manifestation within the spectrum of each disorder and is attributed to the action of humoral and cellular immunity in brain regions such as the basal ganglia. Depending on the pathophysiology, immunotherapy can be effective, while Parkinson's specific therapies are usually less effective., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Paraneoplastic syndromes are remote effects of cancer caused by an autoimmune response triggered by tumor cells. Paraneoplastic Neuromyelitis Optica Spectrum Disorders (NMOSD) has been previously described, but the underlying mechanism for these rare cases is not well characterized. This paper presents a newly described case series of paraneoplastic NMOSD, including 2 new histological types of cancer and histological validation., Methods: The UBC NMO clinic database was surveyed and identified 6 patients with paraneoplastic NMOSD. In 2 cases, aquaporin-4 (AQP4) immunoreactivity was assessed on patients' tumor specimens., Results: The mean age at NMOSD diagnosis was 56 years old and 5/6 patients were older than 50 years old. 4/6 patients with paraneoplastic NMOSD have positive AQP4 antibodies. The median time between NMOSD and cancer was 12 months. Two new cancer types- serous ovarian carcinoma and adrenocortical carcinoma - were found in paraneoplastic NMOSD cases. A serous ovarian carcinoma and a thymoma, found in patients with AQP4 serological evidence, showed a positive reactivity to AQP4 immunostaining., Conclusions: Our findings will increase the recognition of NMOSD as a paraneoplastic syndrome. Cancer cells can express AQP4, increasing the likelihood of a direct mechanism between cancer cells and the development of NMOSD in paraneoplastic cases., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Purpose: Paraneoplastic neurologic disease (PND) is an aberrant immune-mediated response against the nervous system triggered by malignancy. Given the rarity, a paucity of data describing breast cancer-related PND (BC-PND) exists; we sought to further examine this specific patient population., Methods: We retrospectively identified patients at our institution from 1997 to 2016 with BC-PND. Retrospective review with a descriptive analysis determined factors associated with PND and BC, which were compared to national breast cancer median of age (61 years) and average stage at diagnosis (60% local disease)., Results: BC-PND was diagnosed in 56 female patients at a median age of 52.8 years. Only 20% of invasive cancer patients had local disease. The majority of patients were hormone receptor positive and Her2 negative. Neurological symptoms presented prior to BC diagnosis in 57.1% of patients. Of all patients, 30 (53.6%) had autoantibodies detected: Purkinje Cell Cytoplasmic Autoantibody Type-1 (PCA-1[anti-Yo]), n = 10; amphiphysin-IgG, n = 9; Anti-Neuronal Nuclear Autoantibody Type-2 (ANNA-2[anti-Ri]), n = 5; and others, n = 6. The most common neurologic findings were cerebellar ataxia, myelopathy, and myopathy. Immunotherapy benefit was found to be robust (21.6%), mild to moderate (52.9%), absent (17.6%), or indeterminate (7.8%)., Conclusions: PND symptoms often presented prior to BC diagnosis, with the BC biologic subtype characteristics typical of the general BC population. BC diagnoses were often made at younger ages than that of the general BC population and with later-stage disease. Roughly 75% of patients benefited from immunotherapy. These data provide helpful information to providers treating this population of patients.

Background: Neurology has been continuously transforming by the refinement of molecular diagnostics and the development of disease-modifying treatments. The discovery of new antibody markers has elucidated the pathogenesis, provided the means of diagnostics, and offered cure or treatment for several immune-mediated neurological and neuropsychiatric disorders. The identification of pathogenic and marker autoantibodies has also facilitated defining the associated phenotypic spectra and the overlap among the phenotypes linked to individual immune markers., Review Summary: This survey presents the list of currently known autoimmune encephalitis entities along with the associated marker autoantibodies, highlights the phenotypic and immune pathogenic relationships, calls attention to the recently described rare syndromes, discusses the biological significance of the autoantibodies and targeted molecules, points out the potential postinfectious origin of immune pathogenesis in several of the disorders, and directs the readers to the latest diagnostic guidelines as well as to the generally used treatment approaches., Conclusions and Future Directions: Owing to the successful and usually combined use of various methods to detect serum and cerebrospinal fluid autoantibodies on rodent brain sections, in primary neuronal cell culture, in immune precipitation, and cell-based assays, or in other antigen-specific immune assays (Western blot, enzyme-linked immunosorbent assay, and radioimmune assay), the subgroup of antibody marker-negative autoimmune encephalopathy syndromes is contracting, whereas the numbers of entities within the overall group are expanding. Recognition of the correct diagnosis is becoming increasingly rewarding not only for neurologists, but also for pediatric neurologists and psychiatrists.

Importance: A novel astrocytic autoantibody has been identified as a biomarker of a relapsing autoimmune meningoencephalomyelitis that is immunotherapy responsive. Seropositivity distinguishes autoimmune glial fibrillary acidic protein (GFAP) meningoencephalomyelitis from disorders commonly considered in the differential diagnosis., Objective: To describe a novel IgG autoantibody found in serum or cerebrospinal fluid that is specific for a cytosolic intermediate filament protein of astrocytes., Design, Setting, and Participants: Retrospective review of the medical records of seropositive patients identified in the Mayo Clinic Neuroimmunology Laboratory from October 15, 1998, to April 1, 2016, in blinded comprehensive serologic evaluation for autoantibody profiles to aid the diagnosis of neurologic autoimmunity (and predict cancer likelihood)., Main Outcomes and Measures: Frequency and definition of novel autoantibody, the autoantigen's immunochemical identification, clinical and magnetic resonance imaging correlations of the autoantibody, and immunotherapy responsiveness., Results: Of 103 patients whose medical records were available for review, the 16 initial patients identified as seropositive were the subject of this study. Median age at neurologic symptom onset was 42 years (range, 21-73 years); there was no sex predominance. The novel neural autoantibody, which we discovered to be GFAP-specific, is disease spectrum restricted but not rare (frequency equivalent to Purkinje cell antibody type 1 [anti-Yo]). Its filamentous pial, subventricular, and perivascular immunostaining pattern on mouse tissue resembles the characteristic magnetic resonance imaging findings of linear perivascular enhancement in patients. Prominent clinical manifestations are headache, subacute encephalopathy, optic papillitis, inflammatory myelitis, postural tremor, and cerebellar ataxia. Cerebrospinal fluid was inflammatory in 13 of 14 patients (93%) with data available. Neoplasia was diagnosed within 3 years of neurologic onset in 6 of 16 patients (38%): prostate and gastroesophageal adenocarcinomas, myeloma, melanoma, colonic carcinoid, parotid pleomorphic adenoma, and teratoma. Neurologic improvement followed treatment with high-dose corticosteroids, with a tendency of patients to relapse without long-term immunosuppression., Conclusions and Relevance: Glial fibrillary acidic protein-specific IgG identifies a distinctive, corticosteroid-responsive, sometimes paraneoplastic autoimmune meningoencephalomyelitis. It has a lethal canine equivalent: necrotizing meningoencephalitis. Expression of GFAP has been reported in some of the tumor types identified in paraneoplastic cases. Glial fibrillary acidic protein peptide-specific cytotoxic CD8+ T cells are implicated as effectors in a transgenic mouse model of autoimmune GFAP meningoencephalitis.

Introduction: Systemic malignant diseases cause the induction of autoimmunity, for example, paraneoplastic syndromes. There are no proofs of paraneoplastic syndromes in primary brain tumors. The aim of the study was to evaluate the involvement of the peripheral nervous system, together with an assessment of onconeuronal and antineural antibodies as indicators of humoral immune response against nervous system in patients with primary brain tumors., Materials and Methods: Clinical examinations, electrophysiological studies of peripheral nerves (motor and sensory conduction velocity studies, conduction velocity distribution tests, thermal and vibratory quantitative sensory tests, and sympathetic skin response tests) and muscles, blood sampling collection (assessment of onconeuronal, and antineural antibodies) were performed on 33 patients with newly recognized primary brain tumors within 2-4 days after their admission to our department., Results: We revealed statistically significant changes of peripheral nerves, more pronounced in the peroneal nerve in standard and conduction velocity distribution tests, as well as in sympathetic skin responses. We revealed significantly higher vibratory thresholds, and pain thresholds for cold and warm in the upper and lower limbs in the study group than in the controls. In five patients, we have identified anti-neuroendothelium, anti-GFAP, anti-MAG, anti-PCNA, and anti-Ro52 antibodies., Conclusions: In patients with primary brain tumors, electrophysiological changes in peripheral nerves, together with the presence of the antineural antibodies suggest an autoimmune humoral response, and make the diagnosis of paraneoplastic neurological syndrome possible.

Introduction: Stiff person syndrome is a rare autoimmune, neurological disorder characterized by progressive rigidity and episodic painful spasms, predominantly affecting the proximal limbs and axial muscles, and leading to progressive disability. We report the case of a child who developed symptoms compatible with stiff person syndrome during treatment for pleuropulmonary blastoma., Patient Description: A 3-year, 5-month-old girl was admitted for gradually worsening postural tremor, painful spasms, and generalized stiffness. Since the age of 3 years, she had been on adjuvant chemotherapy for pleuropulmonary blastoma before surgical resection. Brain magnetic resonance imaging and electroencephalographic findings were normal. Although serologic tests for autoimmune disease, including paraneoplastic antibodies and antiglutamic acid decarboxylase antibodies, were unremarkable, her findings were attributed to a paraneoplastic syndrome based on her clinical features and medical history. However, following the planned pulmonary lobectomy, her symptoms were paradoxically aggravated, with continuous motor unit potential at rest on electromyography, which occurs in stiff person syndrome. She gradually improved during postadjuvant chemotherapy with simultaneous immunotherapy including intravenous immunoglobulins and methylprednisolone, and she had recovered completely when evaluated at the 22-month follow-up visit after completion of her treatment for pleuropulmonary blastoma., Conclusion: We present the first documented child with stiff person syndrome associated with pleuropulmonary blastoma. The marked clinical improvement following chemotherapy for pleuropulmonary blastoma was yet more proof of the pleuropulmonary blastoma-related stiff person syndrome. In children with a malignancy and stiff person syndrome, a paraneoplastic syndrome should be considered and the treatment for the malignancy must be undertaken., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objectives: To provide an overview of paraneoplastic nerve hyperexcitability syndromes., Methods: An extensive review of the literature on nerve hyperexcitability was performed. Particular attention was paid to Isaacs' syndrome and Morvan's syndrome, as well as their relationship to neoplasia., Results: An overview of the history, clinical manifestations (including neurophysiologic findings), pathophysiology, and management is presented. Clinical differences between the exclusively peripheral nervous system involving Isaacs' syndrome and Morvan's syndrome, which also involves the central nervous system (CNS) are detailed. The role of immune-mediated dysfunction of specific components of the voltage-gated potassium channel (VGKC) complex in the pathophysiology of these syndromes is explained. Finally, the limited data on management of these syndromes, including the use of antiepileptic and immunomodulatory therapies are discussed., Conclusion: Nerve hyperexcitability syndrome represents a spectrum of neuroimmunologic diseases, which are often paraneoplastic in etiology.

Objectives: Paraneoplastic neurological syndromes (PNSs) are rare disorders in association with cancer and sub-divided into "classical" and "non-classical" syndromes according to a 2004 consensus paper proposed by a panel of PNS experts. "Classical" PNSs are regarded to account for the vast majority of cases. However, systematic reports on clinical PNS manifestations are rare. Therefore, we analyzed the spectrum of PNS in our clinic., Methods: We retrospectively investigated medical records from consecutive patients diagnosed with definite PNS and serological evidence of well-characterized onconeural antibodies (anti-Hu, Yo, Ri, CV2/CRMP5, Ma1, Ma2, and amphiphysin) analyzed between 1991 and 2014 in our clinic., Results: Of the 50 patients identified with onconeural antibody-positive PNS, 28 patients (56.0%) had "classical" PNS, and 22 (44.0%) "non-classical" PNS. Subacute cerebellar degeneration was the most frequent "classical" syndrome, brainstem encephalitis and subacute sensorimotor neuronopathy the most frequent "non-classical" syndromes. Anti-Hu antibodies were most frequent in both groups. 86.1% of patients developed neurological symptoms before the cancer was known. No differences between "classical" and "non-classical" syndromes were detected with respect to age, tumor entities and median time to diagnosis. However, whereas most patients with "classical" syndromes were females, there was no gender predominance in patients with "non-classical" PNS and the latter had significantly more frequent peripheral neurological syndromes., Conclusions: The so-called "non-classical" PNSs in association with well-characterized onconeural antibodies were more common in our patient population than expected. Therefore, in neurological disorders of unclear etiology with a subacute onset and atypical presentation further diagnostic work-up including investigation of onconeural antibodies is necessary., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Anti-Ma2 encephalitis is a paraneoplastic disorder characterised by brainstem and/or limbic involvement. Eye movement abnormalities can occur in this condition, often with confusion or somnolence. We describe a patient with progressive oscillopsia (with upbeat nystagmus) and unsteadiness, followed by acute pancreatitis. She did not respond to immunomodulatory treatment and subsequently died of complications related to pancreatitis and sepsis. There was no tumour identified at autopsy, but the anti-Ma2 antibodies in her serum and the discovery of a brainstem-predominant inflammatory infiltrate at autopsy strongly suggest a paraneoplastic disorder. Our case illustrates that upbeat nystagmus can be a predominant feature in anti-Ma2 encephalitis; clinicians should consider testing for anti-Ma2 antibodies in patients with upbeat nystagmus of unknown cause.

Cancer polyarthritis is a very rare condition. Here, we present a case of cancer polyarthritis, who also had mononeuritis simplex as a manifestation of paraneoplastic neuralgic syndrome. A 71-year-old man, who initially presented symmetrical polyarthritis and unilateral posterior interosseous nerve palsy, was subsequently diagnosed to have gastric cancer. Total gastrectomy was performed, and his polyarthritis and the palsy simultaneously disappeared within 2 weeks after the resection. His gastric cancer was found to be metastasized to his liver 16 months after the total gastrectomy; however, the polyarthritis and the palsy did not recurrent throughout his course. The polyarthritis in this case was diagnosed as a cancer polyarthritis from its features. On the other hand, the isolated posterior interosseous nerve palsy in this case met the diagnostic criteria for paraneoplastic neurological syndrome. This case was also unique in that the manifestations of paraneoplastic syndromes did not recur even after the metastasis of the primary cancer, suggesting that some specific clones in the cancer were responsive to the manifestations of paraneoplastic syndromes. Our case suggested that relapse of the manifestations of paraneoplastic syndromes may not always herald the recurrence of primary or metastatic tumour, and other tumour markers and signs should be periodically followed to search for the recurrence of the tumours.

Anti-N-methyl-d-aspartate (NMDA) receptor encephalitis is a recently described potentially lethal but treatable disorder that often occurs as a paraneoplastic manifestation of ovarian teratomas. We report three women with this disorder who presented with subacute onset of delirium, seizures and autonomic instability. Anti-NMDA receptor antibodies were detectable in the serum or cerebrospinal fluid of each patient. Ovarian masses were detected in two patients, and subsequently excised. In the third patient, an empirical bilateral salpingo-oophorectomy was performed and revealed a microscopic neoplasm. All patients experienced slow reversal of the neurological symptoms following surgery and immunotherapy. Our experience suggests that prompt syndrome recognition followed by tumor removal and immunotherapy usually results in neurological recovery., (© 2012 The Authors Acta Obstetricia et Gynecologica Scandinavica© 2012 Nordic Federation of Societies of Obstetrics and Gynecology.)

Chorea and other movement disorders are rarely described as paraneoplastic. The aim of this study was to describe 13 patients with paraneoplastic chorea and dystonia collected by the members of the paraneoplastic neurological syndrome (PNS) EuroNetwork and to review 29 cases from the literature. We analyzed neurological symptoms, severity of the neurological syndrome, delay in neurological diagnosis, associated cancer, oncological and neurological treatments received, and outcome. Eleven (1.2%) out of 913 patients with PNS were identified in the EuroNetwork register. Two more patients not included in the register were added. The overall population consisted of 13 patients with a median age of 75 years (range 49-82 years). In most patients, the movement disorder was classical choreoathetosis with symmetric involvement of the trunk, neck, and limbs. A minority of patients presented unilateral chorea, dystonia, and orobuccal dyskinesia. Associated symptoms, as polyneuropathy, encephalitis, psychiatric disturbances, or visual defects, were often present. The movement disorder usually had a subacute course. The most frequently associated cancer was small cell lung cancer (SCLC). Lymphoma, bowel, or kidney cancers were also reported. CV2/CRMP5 was the most frequently associated antibody, followed by Hu. Hyperintense lesions of the basal ganglia on T2-weighted images were seldom observed. Response to cancer therapy was observed in a minority of patients, but survival was short (17 months). As in other neurological diseases, movement disorders should also be suspected as paraneoplastic when they develop subacutely in older patients (usually over 50) and often in the presence of other ancillary neurological symptoms.

Paraneoplastic neurological syndromes (PNS) are rare diseases defined so far by the presence of a neurological disorder associated with cancer in the absence of invasion of the nervous system by tumor cells. Discovery of circulating autoantibodies specific for these patients has revolutionized the diagnosis and understanding of these syndromes and demonstrated a role of the immune system in the neurological syndromes. Until recent years, we thought that these autoantibodies were only markers of the disease and had no role in the pathophysiology. The recent description of autoantibodies directed against membrane receptors or channels and playing a direct pathological role has transformed the concept of PNS. Especially, it appears that many patients may have a neurological syndrome and autoantibodies without cancer. This results in a classification based on the nature of the autoantibodies associated with neurological syndrome. In case of autoantibodies targeting intracellular antigens, cancer is almost always associated, the neurological disorders are mainly related to neuronal death, patients are rarely sensitive to immunomodulatory treatments and cellular immunity appears to play a major role. In contrast, patients with autoantibodies targeting membrane antigens (receptors, channels or receptor associated proteins) have rarely cancer, neurological disorders are related to a reversible neuronal dysfunction, patients are mostly sensitive to immunomodulatory treatments and it seems that humoral immunity and autoantibodies play a major role., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

The last three decades have seen major advances in the understanding of paraneoplastic and idiopathic autoimmune disorders affecting the central nervous system (CNS). Neural-specific autoantibodies and their target antigens have been discovered, immunopathology and neuroimaging patterns recognized and pathogenic mechanisms elucidated. Disorders accompanied by autoantibody markers of neural peptide-specific cytotoxic effector T cells [such as anti-neuronal nuclear antibody type 1 (ANNA-1, aka anti-Hu), Purkinje cell antibody type 1 (PCA-1, aka anti-Yo) and CRMP-5 IgG] are generally poorly responsive to immunotherapy. Disorders accompanied by neural plasma membrane-reactive autoantibodies [the effectors of synaptic disorders, which include antibodies targeting voltage-gated potassium channel (VGKC) complex proteins, NMDA and GABA-B receptors] generally respond well to early immunotherapy. Here we describe in detail the neuropathological findings and pathophysiology of paraneoplastic CNS disorders with reference to antigen-specific serology and neurological and oncological contexts.

Purpose of Review: The most relevant advances in immune-mediated movement disorders are described, with emphasis on the clinical--immunological associations, novel antigens, and treatment., Recent Findings: Many movement disorders previously considered idiopathic or degenerative are now recognized as immune-mediated. Some disorders are paraneoplastic, such as anti-CRMP5-associated chorea, anti-Ma2 hypokinesis and rigidity, anti-Yo cerebellar ataxia and tremor, and anti-Hu ataxia and pesudoathetosis. Other disorders such as Sydenham's chorea, or chorea related to systemic lupus erythematosus and antiphospholipid syndrome occur in association with multiple antibodies, are not paraneoplastic, and are triggered by molecular mimicry or unknown mechanisms. Recent studies have revealed a new category of disorders that can be paraneoplastic or not, and associate with antibodies against cell-surface or synaptic proteins. They include anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis, which may cause dyskinesias, chorea, ballismus or dystonia (NMDAR antibodies), the spectrum of Stiff-person syndrome/muscle rigidity (glutamic acid decarboxylase, amphiphysin, GABA(A)-receptor-associated protein, or glycine receptor antibodies), neuromyotonia (Caspr2 antibodies), and opsoclonus--myoclonus--ataxia (unknown antigens)., Summary: Neurologists should be aware that many movement disorders are immune-mediated. Recognition of these disorders is important because it may lead to the diagnosis of an occult cancer, and a substantial number of patients, mainly those with antibodies to cell-surface or synaptic proteins, respond to immunotherapy.

Objective: To report the clinical phenotype and outcome of isolated paraneoplastic myelopathy., Methods: We systematically reviewed clinical, serologic, and MRI data for 31 patients (20 female) who presented with an isolated myelopathy and coexisting cancer: carcinoma (lung, 9; breast, 7; kidney, 2; thyroid, 2; ovary/endometrium, 2), melanoma (2), or other cancer (3), or a paraneoplastic autoantibody with strong cancer association (amphiphysin-immunoglobulin G [IgG], 9; collapsin response-mediator protein 5-IgG, 9; Purkinje-cell cytoplasmic autoantibody type 1, 2; antineuronal nuclear autoantibody [ANNA]-1, 1; ANNA-3, 1)., Results: Of 31 patients who presented with a progressive myelopathy, symptom onset was subacute in 16 (52%). The median age was 62 years. CSF abnormalities included elevated protein (>45 mg/dL), 22; pleocytosis, 15; excess oligoclonal bands (normal <4), 7. MRI cord abnormalities identified in 20 patients were longitudinally extensive (>3 vertebral segments), 14; symmetric tract or gray matter-specific signal abnormality, 15 (enhancing in 13). Myelopathy preceded cancer diagnosis in 18 patients (median interval 12 months; range 2-44). After myelopathy onset, 26 patients underwent oncologic treatment, immunosuppressive treatment (median delay to commencing immunotherapy 9.5 months [range 1-54]), or both; only 8 improved (31%). At last neurologic evaluation (median interval after onset 17 months; range 1-165 months), 16 patients (52%) were wheelchair-dependent (median time from onset to wheelchair 9 months [range 1-21]). Ten patients died after a median of 38 months from symptom onset (range 7-152)., Conclusion: Symmetric, longitudinally extensive tract or gray matter-specific changes on spinal MRI should raise suspicion for a paraneoplastic myelopathy. Resulting disability is often severe. Only a minority of patients improve with treatment.

We report two cases of the rare neurological paraneoplastic syndrome, limbic encephalitis, as the initial presentation of small cell lung cancer. The first case responded to treatment of the underlying malignancy, while the second required more acute treatment in the intensive care setting. In this case, initial treatment was with immunosuppression to achieve a degree of stability before the underlying malignancy could be treated. Both cases had significant improvement in neurological function. These cases highlight the importance of directed investigation to try and identify an underlying malignancy in patients in whom a diagnosis of limbic encephalitis is made, and the difficulty in managing such patients., (© 2011 Blackwell Publishing Asia Pty Ltd.)

Introduction: A paraneoplastic syndrome characterized by neuropsychiatric symptoms, involuntary movements and seizures has been recently associated with antibodies targeting NMDA (N-methyl-D-aspartate) receptor in patients with an ovarian teratoma. Severe neurological impairment is frequent and treatment in the intensive care unit is often required because of ventilatory failure and life-threatening autonomic instability. Tumor removal is curative in many cases and neurological improvement is demonstrated shortly after surgery., Case Report: Here we report on a patient with paraneoplastic encephalitis manifested by unconsciousness and coreo-athetosic movements related to NMDA receptor antibodies associated with an immature ovarian teratoma grade III. She made a complete recovery after oophorectomy, intravenous immunoglobulin and corticosteroids., Conclusions: Treatment of paraneoplastic syndromes is based on specific therapy for underlying tumor associated to immunomodulators. As in this case, anti-NMDA encephalitis may significantly improve after tumor removal and intra-venous immunoglobuline.

Paraneoplastic neurologic syndromes are rare disorders that have potentially devastating effects on the developing brain. Recently, there has been increased interest in possible immunotherapy for these disorders. Recognition of paraneoplastic syndromes in children may lead to early detection and treatment of the pediatric cancer and may diminish the neurologic damage that is the major source of morbidity in children with successfully treated tumors. This article reviews the presenting symptoms, immunology, long-term sequelae, and management options for paraneoplastic neurologic syndromes, focusing on those most commonly reported in children: opsoclonus-myoclonus ataxia, limbic encephalitis, and anti-NMDAR encephalitis. The child neurologist plays an important role in recognizing these disorders, initiating a tumor search, and directing ongoing treatment and management of neurologic symptoms after oncologic treatment is complete. Given the rarity of these conditions, multisite collaborative efforts are needed to develop standardized approaches to characterization and treatment.

Extraskeletal myxoid chondrosarcoma is a rare tumor with less than 100 cases reported in the literature. The prevalence of anti-Hu positive myxoid chondrosarcoma-associated paraneoplastic subacute cerebellar degeneration is exceedingly rare. We present a report of a patient with confirmed myxoid chondrosarcoma-associated paraneoplastic subacute cerebellar degeneration, who exhibited marked improvement within 1 week of receiving chemotherapy, intravenous immunoglobulin (IVIG), and hydrocortisone treatment.

The article provides an overview on the diagnosis and pathogenesis of paraneoplastic neurological disorders (PNDs), and subsequently the current therapeutic strategies in these patients. PNDs are nervous system dysfunctions in cancer patients, which are not due to a local effect of the tumor or its metastases. Most of these clinically defined syndromes in adults are associated with lung cancer, especially small-cell lung cancer, lymphoma and gynecological tumors. In a part of the PND, an overlapping of different clinical syndromes can be observed. Highly specific autoantibodies directed against onconeuronal antigens led to the current hypothesis of an autoimmune pathophysiology. Whereas the most central nervous PNDs are more T-cell-mediated, limbic encephalitis can be caused by pathogenic receptor autoantibodies. The PND of the neuromuscular junction and paraneoplastic autonomic neuropathy are mainly associated with receptor or ion channel autoantibodies. The childhood opsoclonus-myoclonus syndrome and the PNDs associated with receptor/ion channel autoantibodies often respond to immunosuppressive therapies, plasmapheresis and intravenous immunoglobulins. By contrast, most CNS PNDs associated with defined antineuronal antibodies directed against intracellular antigens only stabilize after tumor treatment.

Antibodies to the N-methyl-d-aspartate subtype of glutamate receptor have been associated with a newly-described encephalopathy that has been mainly identified in young females with ovarian tumours. However, the full clinical spectrum and treatment responses are not yet clear. We established a sensitive cell-based assay for detection of N-methyl-d-aspartate receptor antibodies in serum or cerebrospinal fluid, and a quantitative fluorescent immunoprecipitation assay for serial studies. Although there was marked intrathecal synthesis of N-methyl-d-aspartate receptor antibodies, the absolute levels of N-methyl-d-aspartate receptor antibodies were higher in serum than in cerebrospinal fluid. N-methyl-d-aspartate receptor antibodies were of the immunoglobulin G1 subclass and were able to activate complement on N-methyl d-aspartate receptor-expressing human embryonic kidney cells. From questionnaires returned on 44 N-methyl-d-aspartate receptor antibody-positive patients, we identified a high proportion without a detected tumour (35/44, 80%: follow-up 3.6-121 months, median 16 months). Among the latter were 15 adult females (43%), 10 adult males (29%) and 10 children (29%), with four in the first decade of life. Overall, there was a high proportion (29%) of non-Caucasians. Good clinical outcomes, as defined by reductions in modified Rankin scores, correlated with decreased N-methyl-d-aspartate receptor antibody levels and were associated with early (<40 days) administration of immunotherapies in non-paraneoplastic patients (P < 0.0001) and earlier tumour removal in paraneoplastic patients (P = 0.02). Ten patients (23%) who were first diagnosed during relapses had no evidence of tumours but had received minimal or no immunotherapy during earlier episodes. Temporal analysis of the onset of the neurological features suggested progression through two main stages. The time of onset of the early features, characterized by neuropsychiatric symptoms and seizures preceded by a median of 10-20 days, the onset of movement disorders, reduction in consciousness and dysautonomia. This temporal dichotomy was also seen in the timing of cerebrospinal fluid, electroencephalographic and in the rather infrequent cerebral imaging changes. Overall, our data support a model in which the early features are associated with cerebrospinal fluid lymphocytosis, and the later features with appearance of oligoclonal bands. The immunological events and neuronal mechanisms underlying these observations need to be explored further, but one possibility is that the early stage represents diffusion of serum antibodies into the cortical grey matter, whereas the later stage results from secondary expansion of the immunological repertoire within the intrathecal compartment acting on subcortical neurons. Four patients, who only had temporal lobe epilepsy without oligoclonal bands, may represent restriction to the first stage.

Paraneoplastic neurological syndromes (PNSs) are the remote effects of cancer on the nervous system. The peripheral nervous system is an important targets of PNS. The neuropathies associated with PNS are reviewed in this article. Among the various paraneoplastic neuropathies, the main classical syndorome of PNS is subacute sensory neuronopathy that involves the cell bodies of sensory neurons in the dorsal root ganglia. Its clinical symptoms include sensory ataxia. Onconeuronal antibodies such as anti-Hu and anti-CV2/CRMP5 antibodies are frequently associated with this syndrome. In contrast to this classical form of PNS, non-classical syndromes are considered as heterogeneous neuropathies. The clinical features of non-classical syndromes are variable and no evident association between a clinical phenotype and onconeuronal antibodies has been established. Early detection and treatment of cancer is an essential for management of PNS. Neuropathies with paraproteinemia are also important clinical entities of PNS. IgM M-protein is most likely to cause neuropathy. Patients with IgM paraproteinemic neuropathy is usually characterized by predominan distal and sensory impairment, prolonged distal motor latencies in nerve conduction studies, and the presence of anti-MAG and SGPG antibodies.

Background: Kinsbourne syndrome or opsoclonus myoclonus syndrome (OMS) is characterized by rapid, involuntary, irregular conjugate eye movements (opsoclonus), myoclonic jerking of the limbs and trunk, ataxia, and behavioral disturbances. In general, the outcome of neurologic and behavioral symptoms is poor. Studies on quality of life (Qol) and recovery after very long-term follow-up of children with OMS are lacking., Methods: We studied long-term cancer survival, neurologic recovery, and Qol of a consecutive series of eight patients with OMS that were treated in our center. Two cross-sectional follow-up evaluations were conducted at a 3-year interval (T1 and T2)., Results: In four out of eight children with OMS a neuroblastoma (NBL) was diagnosed and surgically removed completely. All children received immuno-modulatory therapy, consisting of prednisone (three children), prednisone and ACTH (four children), or prednisone, ACTH, and gammaglobulin (one child). At T1, median follow-up time was 9.5 years (range 3-14 years) after OMS onset and at T2, 11.6 years (range 6-17 years). Neurologic functioning improved in all children, reflected by a significant improvement of the mean Z-score in the motor domain of the Qol questionnaire at T2 as compared to T1. In contrast, seven children continued to have a severe developmental delay at T2. No significant difference in any of the variables was found between NBL survivors and OMS patients without NBL., Conclusion: Cognitive and behavioral impairments and not a motor impairment, such as ataxia, appear to be predominant at long-term in children with OMS.

Objectives: To report a case of multifocal cortical encephalitis associated with thymoma and to establish an association of this thymoma-related paraneoplastic syndrome with voltage-gated potassium channel antibodies., Design: Case report., Setting: University hospital., Patient: A 43-year-old woman with a history of seropositive myasthenia gravis and successfully treated invasive thymoma. Four years after thymectomy, she presented with seizure and rapidly progressive confusion and aphasia. Myasthenia gravis remained in pharmacological remission. Magnetic resonance imaging of the brain showed innumerable cortically based signal abnormalities as well as extensive left mesial temporal lobe abnormality with minimal enhancement., Results: Chest computed tomography showed abnormal pleural thickening of the left lung, which proved to be recurrent metastatic thymoma. Results of serological evaluation were positive for acetylcholine receptor, striational, and voltage-gated potassium channel antibodies. She showed partial improvement in response to immunotherapy and chemotherapy but ultimately died 2 months later of tumor complications., Conclusions: Thymoma and myasthenia gravis may be associated with other autoimmune neurological disorders including paraneoplastic encephalitis. This second case of thymoma-associated multifocal cortical encephalitis demonstrates that autoimmune encephalitis can extend to cortical regions outside the limbic system. Autoimmune encephalitis should be considered in the differential diagnosis of patients with myasthenia gravis or thymoma who develop new cognitive symptoms.

Neurologic paraneoplastic syndromes (NPSs) result from damage to the nervous system due to the remote effects of cancer not related to metastasis, infection, or metabolic derangements. NPSs are rare, affecting 1 in 10,000 patients with cancer. Pathogenesis is likely related to the immune mechanisms: normal neural tissue is mistakenly attacked due to the similarity in the onconeural antigens expressed by the tumor cells. Among the various "classic" and other NPSs, this review focuses on paraneoplastic movement disorders, including ataxia due to cerebellar degeneration, stiff-person syndrome, opsoclonus-myoclonus syndrome, chorea, parkinsonism, and tremor. The recently described syndrome of paraneoplastic anti-N-methyl-D-aspartate receptor encephalitis is also included, given that these patients have complex movements such as stereotypies and dyskinesias in addition to psychiatric symptoms, altered sensorium, and other neurologic signs. Although variable, treatment and prognosis of NPSs rely heavily on treatment of the underlying malignancy and immunotherapy.

Objective: To describe the clinical utility of the nicotinic ganglionic acetylcholine receptor (alpha3-AChR) autoantibody as a marker of neurological autoimmunity and cancer., Design: Case-control study., Setting: Mayo Clinic, Rochester, Minnesota., Patients: A total of 15,000 patients seen at Mayo Clinic (2005-2007) and evaluated on a service basis for paraneoplastic neurological autoimmunity for whom clinical information was obtained retrospectively by medical record review as well as 457 neurologically asymptomatic patients or control subjects of whom 173 were healthy, 245 had lung cancer, and 39 had systemic lupus erythematosus or Sjögren syndrome., Outcome Measures: Neurological, oncological, and serological associations of alpha3-AChR autoantibody seropositivity., Results: Of 15,000 patients tested on a service basis, 1% were seropositive (median, 0.12 nmol/L; range, 0.03-18.8 nmol/L; normal, < or =0.02 nmol/L), 55% were male, and the median age was 65 years. Cancer was found (new or by history) in 24 of 78 patients evaluated for cancer while at Mayo Clinic (30%); 43% had adenocarcinoma (more patients had breast cancer than prostate, lung, and gastrointestinal cancers; each of the latter groups had about the same number of patients). Of 12 patients with high antibody values (> or =1.00 nmol/L), 83% had pandysautonomia. Of 85 patients with medium antibody values (0.10-0.99 nmol/L), neurological presentations were more diverse and included peripheral neuropathies (36%), dysautonomia (20%, usually limited), and encephalopathy (13%). Of 58 patients with low antibody values (0.03-0.09 nmol/L), 54% had a nonautoimmune neurological disorder or no neurological disorder. Of 245 control patients with lung cancer, 7.8% were seropositive. Only 1 of 212 control patients without cancer (0.5%) was seropositive (P < .001)., Conclusion: The detection of alpha3-AChR autoantibody aids the diagnosis of neurological autoimmunity and cancer.

An 83-year-old woman presented with a predominantly left upper limb sensory ganglionopathy. She was found to have metastatic, poorly differentiated, neuroendocrine malignancy. Anti-neuronal antibodies were not detected.