Paraneoplastic neurological syndromes

Atezolizumab- and bevacizumab -induced encephalitis in a patient with advanced hepatocellular carcinoma: a case report and literature review

Treatment with atezolizumab and bevacizumab is the first-line therapy for unresectable hepatocellular carcinoma. Although immune checkpoint inhibitors are novel and effective treatments, they can induce immune-related adverse events. However, neurological immune-related adverse events have rarely been reported. We report the case of a man in his 40s with hepatocellular carcinoma who developed life-threatening encephalitis after atezolizumab plus bevacizumab was administered. The patient presented with fever, headache, altered mentality, and general epileptic seizures, ten days after administration. Cerebrospinal fluid analysis showed elevated white blood cells and elevated protein levels, but revealed no infection or malignancy. Brain magnetic resonance imaging showed diffuse leptomeningeal enhancement in both the cerebrum and cerebellum. As immune checkpoint inhibitor-induced encephalitis was strongly suspected, steroid pulse therapy was initiated and neurological symptoms quickly improved. The patient was discharged after 66 days of hospitalization, and administration of sorafenib and radiotherapy was started for the hepatocellular carcinoma on an outpatient basis. This case demonstrates the importance of recognizing neurological immune-related adverse events following atezolizumab and bevacizumab treatment for early intervention. We discuss this case in comparison to available literature and previous two cases of Atezolizumab- and bevacizumab- induced encephalitis in hepatocellular carcinoma.

Small-cell Lung Carcinoma with Gastrointestinal Pseudo-obstruction as a Paraneoplastic Neurological Syndrome Elicited by an Immune Checkpoint Inhibitor

Gastrointestinal pseudo-obstruction (GIPO) is a phenotype of the paraneoplastic neurological syndrome (PNS). We herein report a case of small-cell lung carcinoma (SCLC) with GIPO elicited by an immune checkpoint inhibitor (ICI). A 75-year-old man with SCLC developed intractable intestinal obstruction after receiving one course of anticancer drugs (durvalumab, etoposide, and carboplatin). The serum anti-Hu antibody (Hu-Ab) was positive, and the patient was diagnosed with GIPO. Corticosteroid treatment did not improve the GIPO, and the patient died. There are few reports of GIPO after ICI treatment in patients with lung cancer, so a further investigation will be required to elucidate the mechanism by which ICIs elicit PNS. Checking for neuronal antibodies may help identify patients with SCLC who are at risk of developing PNS due to ICI treatment.

Atypical Presentation of Gall Bladder Adenocarcinoma as Paraneoplastic Myeloneuropathy

ABSTRACT

Paraneoplastic neurologic syndromes are a rare, heterogeneous group of complications associated with malignancy, unrelated to direct tumor invasion or metastasis. They are the remote effects of a malignancy owing to immune-mediated reaction toward the antigens that are common to both the malignant and normal cells. Few paraneoplastic syndromes are reported with gall bladder cancer. However, neurological symptoms are infrequent. Here we share an interesting case of adenocarcinoma of gall bladder with initial presentation as a paraneoplastic noncompressing myeloneuropathy.

Plasmapheresis and IVIG for Treatment of Non-Tumor Anti-Tr/DNER Antibody-Associated Ataxia: A Case Report

Autoimmune cerebellar ataxia (ACA) is a condition characterized by progressive ataxia resulting from an immune-mediated attack on cerebellar structures. The presence of anti-Tr/DNER antibodies, strongly associated with Hodgkin lymphoma, has been identified in ACA. However, cases with no underlying malignancy are rare. We report the case of a 49-year-old woman presenting with progressive ataxia, slurred speech, and dizziness over three months. The patient exhibited significant cerebellar symptoms, including dysarthria and limb ataxia, without signs of other systemic illnesses. Comprehensive investigations, including imaging, lumbar puncture, and autoantibody testing, were performed. The cerebrospinal fluid (CSF) sample revealed positivity for Tr/DNER antibodies, leading to a diagnosis of autoimmune cerebellar ataxia. The patient underwent nine sessions of plasmapheresis, followed by six doses of intravenous immunoglobulin (IVIG), resulting in significant clinical improvement. Despite extensive cancer screening, no underlying malignancy was detected, suggesting a non-tumor origin of anti-Tr/DNER antibodies. The patient's gait improved, ataxia resolved, and cerebellar tests normalized following treatment. The patient was further managed with rituximab treatment every six months. This case represents a presentation of anti-Tr/DNER-associated autoimmune cerebellar ataxia without malignancy. The successful treatment with plasmapheresis and IVIG suggests that these interventions may be effective in managing autoimmune cerebellar ataxia associated with anti-Tr/DNER antibodies. Further research is needed to understand the underlying mechanisms of this condition and to determine the optimal treatment strategies.

Anti-α-Amino-3-Hydroxy-5-Methyl-4-Isoxazolepropionic Acid (AMPA) Receptor Antibody Encephalitis in an Immunosuppressed Patient With Myasthenia Gravis Post-thymoma Treatment

Anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor encephalitis is a rare form of autoimmune encephalitis. We report a case of a patient with myasthenia gravis post-thymoma treatment who presented with deteriorating mental status. She was found to have positive AMPA receptor titers in her cerebrospinal fluid and subsequently attained full recovery. Of the limited number of cases that were documented, we report the only case of a patient who was previously immunocompromised to develop the condition. Even though autoimmune encephalitis is an emerging condition, its early differentiation from other causes of encephalitis is crucial in the prognosis of the patient.

Paraneoplastic syndromes in patients with melanoma

Paraneoplastic syndromes are a group of rare clinical conditions characterized by a diverse array of systemic manifestations that arise in association with malignant tumours, often due to the production of bioactive substances by the tumour or an autoimmune response to the tumour. Melanoma, a malignant skin neoplasm originating from melanocytes, has been associated with various paraneoplastic syndromes. This paper provides an overview of the key paraneoplastic syndromes observed in patients with melanoma. Paraneoplastic syndromes in melanoma can manifest with neurological, dermatological, endocrine, haematological, and rheumatological symptoms, among others. Melanoma-associated retinopathy was the most reported paraneoplastic syndrome; this entity is characterized by a spectrum of retinal abnormalities. Paraneoplastic neurological syndromes, such as paraneoplastic encephalitis and paraneoplastic cerebellar degeneration, are among the most frequently reported. The pathophysiology of paraneoplastic syndromes often involves the production of autoantibodies against neuronal or tumour antigens, immune-mediated reactions, or the release of cytokines and growth factors from the tumour. Management strategies for paraneoplastic syndromes associated with melanoma primarily focus on treating the underlying malignancy, which may lead to resolution or improvement of the paraneoplastic manifestations. Immune-modulating therapies, including corticosteroids, intravenous immunoglobulins, and plasmapheresis, may be considered in selected cases to ameliorate symptoms and suppress the autoimmune response. In conclusion, paraneoplastic syndromes in patients with melanoma are a complex and diverse group of clinical entities with a broad range of presentations. Further research is needed to enhance our understanding of the mechanisms and therapeutic options for paraneoplastic syndromes associated with melanoma.

Neurological features of Hansen disease: a retrospective, multicenter cohort study

To elucidate the neurological features of Hansen disease. The medical records of patients with confirmed Hansen disease transferred from the neurology department were reviewed, and all medical and neurological manifestations of Hansen disease were assessed. Eleven patients with confirmed Hansen disease, 10 with newly detected Hansen disease and 1 with relapsed Hansen disease, who visited neurology departments were enrolled. The newly detected patients with Hansen disease were classified as having lepromatous leprosy (LL, n = 1), borderline lepromatous leprosy (BL, n = 2), borderline leprosy (BB, n = 2), borderline tuberculoid leprosy (BT, n = 1), tuberculoid leprosy (TT, n = 2), or pure neural leprosy (PNL, n = 2). All of the patients with confirmed Hansen were diagnosed with peripheral neuropathy (100.00%, 11/11). The symptoms and signs presented were mainly limb numbness (100.00%, 11/11), sensory and motor dysfunction (100.00%, 11/11), decreased muscle strength (90.90%, 10/11), and skin lesions (81.81%, 9/11). Nerve morphological features in nerve ultrasonography (US) included peripheral nerve asymmetry and segmental thickening (100.00%, 9/9). For neuro-electrophysiology feature, the frequency of no response of sensory nerves was significantly higher than those of motor nerves [(51.21% 42/82) vs (24.70%, 21/85)(P = 0.0183*)] by electrodiagnostic (EDX) studies. Nerve histological features in nerve biopsy analysis included demyelination (100.00%, 5/5) and axonal damage (60.00%, 3/5). In addition to confirmed diagnoses by acid-fast bacteria (AFB) staining (54.54%, 6/11) and skin pathology analysis (100.00%, 8/8), serology and molecular technology were positive in 36.36% (4/11) and 100.00% (11/11) of confirmed patients of Hansen disease, respectively. It is not uncommon for patients of Hansen disease to visit neurology departments due to peripheral neuropathy. The main pathological features of affected nerves are demyelination and axonal damage. The combination of nerve US, EDX studies, nerve biopsy, and serological and molecular tests can improve the diagnosis of Hansen disease.

Paraneoplastic Cerebellar Degeneration Associated with Breast Cancer: A Case Report and a Narrative Review

Paraneoplastic neurological syndromes (PNSs) are an uncommon complication of cancer, affecting nearby 1/10,000 subjects with a tumour. PNSs can involve all the central and peripheral nervous systems, the muscular system, and the neuromuscular junction, causing extremely variable symptomatology. The diagnosis of the paraneoplastic disease usually precedes the clinical manifestations of cancer, making an immediate recognition of the pathology crucial to obtain a better prognosis. PNSs are autoimmune diseases caused by the expression of common antigens by the tumour and the nervous system. Specific antibodies can help clinicians diagnose them, but unfortunately, they are not always detectable. Immunosuppressive therapy and the treatment of cancer are the cornerstones of therapy for PNSs. This paper reports a case of PNSs associated with breast tumours and focuses on the most common paraneoplastic neurological syndromes. We report a case of a young female with a clinical syndrome of the occurrence of rigidity in the right lower limb with postural instability with walking supported and diplopia, with a final diagnosis of paraneoplastic cerebellar degeneration and seronegative rigid human syndrome associated with infiltrating ductal carcinoma of the breast.

Breast cancer's hidden partner: meningoencephalitis as a paraneoplastic revelation: a rare presentation of invasive ductal carcinoma of breast: a case report

Introduction and importance

Paraneoplastic neurologic syndromes encompass a group of neurologic disorders arising from pathological processes unrelated to metastasis, metabolic disturbances, infections, coagulopathy, or treatment-related side effects. These syndromes can affect various regions of the nervous system, resulting in diverse clinical manifestations.

Case presentation

The authors present a rare case of anti-amphiphysin-associated meningoencephalitis in a South Asian Pakistani woman. Initially, the patient was managed for suspected infectious meningitis, but empirical treatment failed to yield improvement. Subsequent investigations unveiled a paraneoplastic syndrome secondary to breast cancer.

Discussion

Diagnosing these clinical entities is challenging due to their multifaceted presentations, often leading to delayed identification, increased patient suffering, economic burdens, and preventable complications.

Conclusion

Anti-amphiphysin-associated meningoencephalitis is a rare manifestation of paraneoplastic syndromes. It is crucial to raise awareness among healthcare professionals about the diverse presentations of paraneoplastic syndromes.

Paraneoplastic/autoimmune myelopathies

Paraneoplastic myelopathies are a rare but important category of myelopathy. They usually present with an insidious or subacute progressive neurologic syndrome. Risk factors include tobacco use and family history of cancer. Cerebrospinal fluid analysis usually shows lymphocytic pleocytosis with elevated protein. MRI findings suggest that paraneoplastic myelopathies include longitudinally extensive T2 hyperintensities that are tract-specific and accompanied by enhancement, but spinal MRIs can also be normal. The most commonly associated neural antibodies include amphiphysin and collapsin-response-mediator-protein-5 (CRMP5/anti-CV2) antibodies with lung and breast cancers being the most frequent oncologic accompaniments. The differential diagnosis of paraneoplastic myelopathies includes nutritional deficiency myelopathy (B12, copper) as well as autoimmune/inflammatory conditions such as primary progressive multiple sclerosis or spinal cord sarcoidosis. Patients treated with immune checkpoint inhibitors for cancer may develop myelitis, that can be considered along the spectrum of paraneoplastic myelopathies. Management of paraneoplastic myelopathy includes oncologic treatment and immunotherapy. Despite these treatments, the prognosis is poor and the majority of patients eventually become wheelchair-dependent.

Autoimmune and paraneoplastic neurological disorders: A review of relevant neuroimaging findings

INTRODUCTION

Paraneoplastic neurologic syndromes (PNS) and autoimmune encephalitis (AIE) are immune-mediated disorders. PNS is linked to cancer, while AIE may not Their clinical manifestations and imaging patterns need further elucidation.

OBJECTIVE/AIMS

To investigate the clinical profiles, antibody associations, neuroimaging patterns, treatments, and outcomes of PNS and AIE.

METHODS

A systematic review of 379 articles published between 2014 and 2023 was conducted. Of the 55 studies screened, 333 patients were diagnosed with either PNS or AIE and tested positive for novel antibodies. Data on demographics, symptoms, imaging, antibodies, cancer associations, treatment, and outcomes were extracted.

RESULTS

The study included 333 patients (mean age 54 years, 67% males) with PNS and AIE positive for various novel antibodies. 84% had central nervous system issues like cognitive impairment (53%), rhombencephalitis (17%), and cerebellar disorders (24%). Neuroimaging revealed distinct patterns with high-risk antibodies associated with brainstem lesions in 98%, cerebellar in 91%, hippocampal in 98%, basal ganglia in 75%, and spinal cord in 91%, while low/intermediate-risk antibodies were associated with medial temporal lobe lesions in 71% and other cortical/subcortical lesions in 55%. High-risk antibodies were associated with younger males, deep brain lesions, and increased mortality of 61%, while low/intermediate-risk antibodies were associated with females, cortical/subcortical lesions, and better outcomes with 39% mortality. Associated cancers included seminomas (23%), lung (19%), ovarian (2%), and breast (2%). Treatments included IVIG, chemotherapy, and plasmapheresis. Overall mortality was 25% in this cohort.

CONCLUSION

PNS and AIE have distinct clinical and radiological patterns based on antibody profiles. High-risk antibodies are associated with increased mortality while low/intermediate-risk antibodies are associated with improved outcomes. Appropriate imaging and antibody testing are critical for accurate diagnosis.

Autoimmune encephalitis and paraneoplastic encephalitis: difficulties in diagnosis and management in the ICU

Autoimmune encephalitis (AIE) represents a category of relatively newly described neurological disorders associated with an increasing prevalence, a significant impact on the healthcare system, and a high rate of intensive care unit (ICU) admission. This category of diseases often requires prompt treatment, even before a definitive diagnosis is established. In the ICU, patients present with nonspecific signs and symptoms for AIE, which pose challenges in both management and diagnosis. Patients frequently exhibit dysautonomia, severe physical and psychic agitation, as well as tremors and dyskinesia, all of which complicate the diagnosis. They are prone to developing infections, including ventilator-associated pneumonia, and issues related to difficult venous access and pressure ulcers. Early initiation of immunosuppressive treatment is necessary to improve patients' outcome. Through this article, we aimed to summarize current knowledge in terms of the difficulties in diagnosing and management of this pathology in the ICU, as well as the implications for the healthcare system in terms of human and financial resources.

Seronegative paraneoplastic encephalomyelitis in occult colonic carcinoma

Paraneoplastic neurological syndromes are immune-mediated neurological attacks triggered by malignancies. They are commonly associated with lung, breast, thymus, gynaecological and haematological malignancies. We report a case of a male patient in his late 40s with paraneoplastic encephalomyelitis due to a colonic adenocarcinoma emphasising a low threshold for extensive cancer evaluation in all subacutely presenting neurological syndromes. We also emphasise that the absence of a positive onconeural antibody does not preclude the diagnosis of a paraneoplastic syndrome.

Anti-SOX-1 Antibody-Positive Paraneoplastic Limbic Encephalitis Diagnosed During Small Cell Lung Cancer Treatment

Paraneoplastic neurological syndrome (PNS) mostly presents its symptoms prior to cancer treatment. We present a case of anti-Sry-like high mobility group box 1 (SOX-1) antibody-positive PNS diagnosed during the treatment of small-cell lung cancer (SCLC). A 65-year-old woman with a history of smoking and SCLC (T3N1M0) was hospitalized to receive chemo-radiation therapy. On day 14, the course was complicated by left mastitis associated with febrile neutropenia. Drainage was performed for the left mastitis, and cefepime was initiated. The fever subsided within a few days, but the patient became agitated accompanied by logorrhea. With the exception of mental status, her neurological examination was unremarkable. Due to mildly impaired renal function, cefepime encephalopathy was considered in the differential diagnosis, but the agitation grew worse despite cefepime discontinuation. Further evaluations, including brain magnetic resonance imaging without contrast and cerebrospinal fluid analysis, were unremarkable. Acyclovir and steroid pulse therapy were initiated empirically for herpes simplex virus (HSV) and PNS, respectively. On day 22, acyclovir was discontinued because the HSV polymerase chain reaction test result was negative. On day 26, the serum anti-SOX-1 antibody test was reported to be positive. Other paraneoplastic syndrome-associated antibodies, including anti-amphiphysin, CV2, PNMA2, Ri, Yo, Hu, recoverin, titin, zic 4, GAD 65, Tr, and N-methyl-D-aspartate receptor antibodies, were negative. The agitation improved gradually following the continuation of chemotherapy and steroid treatment. The patient was discharged on day 55 in stable condition. Although PNS mostly presents prior to cancer treatment, it is important to recognize that it may develop during the course of cancer treatment. Evaluation and empirical treatment for PNS should be considered in patients who develop encephalopathy during cancer treatment, as early treatment can lead to a better outcome.

Paraneoplastic encephalitis: clinically based approach on diagnosis and management

Paraneoplastic neurological syndromes (PNSs) comprise a subset of immune-mediated nervous system diseases triggered by an underlying malignancy. Each syndrome usually shows a distinct clinical presentation and outcome according to the associated neural antibodies. PNSs generally have a subacute onset with rapid progression and severe neurological disability. However, some patients may have hyperacute onset or even show chronic progression mimicking neurodegenerative diseases. Updated diagnostic criteria for PNS have been recently established in order to increase diagnostic specificity and to encourage standardisation of research initiatives related to PNS. Treatment for PNS includes oncological therapy and immunomodulation to halt neurological deterioration although current treatment options are seldom effective in reversing disability. Nevertheless, growing knowledge and better understanding of PNS pathogenesis promise better recognition, earlier diagnosis and novel treatment strategies. Considering that PNSs provide a model of effective anticancer immunity, the impact of these studies will extend far beyond the field of neurology.

Immune-related adverse events and immune checkpoint inhibitors: a focus on neurotoxicity and clinical management

INTRODUCTION

Immune checkpoint inhibitors (ICIs) represent an innovative therapeutic approach of oncologic diseases. In Europe, this therapeutic class currently includes eight agents: ipilimumab, pembrolizumab, nivolumab, atezolizumab, avelumab, cemiplimab, durvalumab and dostarlimab. Despite their proved clinical benefits, they can induce immune related adverse events (irADRs), that can also involve the nervous system.

AREAS COVERED

Despite their rarity, neurological irADRs related to ICI-treatments can lead to serious and dangerous complications, highlighting the importance of a strict monitoring of patients. This review aims to summarize the safety profile of ICIs, focusing on their possible neurotoxicity and their management.

EXPERT OPINION

Considering the clinical relevance of ICIs-induced irADRs and that the underlying mechanisms are still not completely understood, the use of ICIs requires extensive safety monitoring. Before to prescribe immunotherapy, oncologists should identify possible individual risk factors that may favor the onset of irADRs. Oncologists and general practitioners should inform and educate patients about the specific toxicities of immunological checkpoint inhibitors, including nervous ones. They should be carefully monitored at least 6 months after the end of treatment. ICIs-related nervous toxicities require a multidisciplinary management, in which neurologists and clinical pharmacologists should participate.

Anti-SOX1 Antibody-positive Small-cell Lung Cancer That Triggered Opsoclonus

A 72-year-old woman with opsoclonus visited our hospital and was diagnosed with small-cell lung cancer. Blood tests revealed anti-SOX1 antibodies, so the patient was diagnosed with paraneoplastic opsoclonus-myoclonus syndrome. After steroid pulse therapy was started, chemotherapy of treatment, the opsoclonus showed an improving trend. Anti-Ri and anti-Hu antibodies have been reported as autoantibodies associated with neoplastic opsoclonus-myoclonus syndrome; however, there are no such reports concerning anti-SOX1 antibody. Therefore, this is a valuable case.

Anti-Zic4 Paraneoplastic Cerebellar Degeneration With Mesial Temporal Lobe Hyperintensity in a Patient With Papillary Thyroid Carcinoma: A Case Report and Review of the Literature

Paraneoplastic cerebellar degeneration (PCD), a subtype of paraneoplastic neurological syndromes (PNSs), is a rare autoimmune neurologic syndrome that usually develops secondary to an underlying malignancy. We present a 49-year-old patient that developed PCD secondary to occult papillary thyroid carcinoma. The patient had progressive difficulty ambulating for 3 years. A neurological exam revealed signs of cerebellar syndrome. Brain magnetic resonance imaging (MRI) showed significant cerebellar atrophy and mesial temporal lobe hyperintensity. Immunological testing was highly positive for anti-CV2 and anti-Zic4 onconeural antibodies. Positron emission tomography (PET)/Computerized tomography (CT) scan revealed significant hypermetabolic uptake of F-18 fluorodeoxyglucose (FGD) by a left thyroid nodule. Histological examination of the nodule was positive for papillary thyroid carcinoma, confirming the diagnosis of PCD. A trial of high-dose methylprednisolone failed to improve the patient's symptoms. This case highlights the importance of maintaining high suspicion for PCD while investigating cases of cerebellar degeneration. Early detection is essential to prevent irreversible damage in affected patients.

Paraneoplastic Syndromes from Head to Toe: Pathophysiology, Imaging Features, and Workup

Patients often have symptoms due to the mass effect of a neoplasm on surrounding tissues or the development of distant metastases. However, some patients may present with clinical symptoms that are not attributable to direct tumor invasion. In particular, certain tumors may release substances such as hormones or cytokines or trigger an immune cross-reactivity between malignant and normal body cells, resulting in characteristic clinical features that are broadly referred to as paraneoplastic syndromes (PNSs). Recent advances in medicine have improved the understanding of the pathogenesis of PNSs and enhanced their diagnosis and treatment. It is estimated that 8% of patients with cancer develop a PNS. Diverse organ systems may be involved, most notably the neurologic, musculoskeletal, endocrinologic, dermatologic, gastrointestinal, and cardiovascular systems. Knowledge of various PNSs is necessary, as these syndromes may precede tumor development, complicate the patient's clinical presentation, indicate tumor prognosis, or be mistaken for metastatic spread. Radiologists should be familiar with the clinical presentations of common PNSs and the selection of appropriate imaging examinations. Many of these PNSs have imaging features that can assist with arriving at the correct diagnosis. Therefore, the key radiographic findings associated with these PNSs and the diagnostic pitfalls that can be encountered during imaging are important, as their detection can facilitate early identification of the underlying tumor, reveal early recurrence, and enable monitoring of the patient's response to therapy. ^© RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Rare case of anti-CV2 paraneoplastic polyneuropathy associated with lung adenocarcinoma

We describe the first case of anti-CV2 paraneoplastic polyneuropathy associated with lung adenocarcinoma. Our patient presented with progressive unsteadiness and numbness involving bilateral upper and lower limbs. He had symmetrical length-dependent lower motor neuron pattern of weakness and numbness involving both small and large fibres with prominent sensory ataxia. An extended workup for the polyneuropathy involving a serum paraneoplastic antineuronal antibody panel showed a positive reaction for anti-CV2 antibody. CT scan of the thorax, abdomen and pelvis revealed a right upper lung nodule and histopathological examination of the nodule revealed lung adenocarcinoma. He was scheduled for chemotherapy following his discharge and there was improvement of his sensorimotor polyneuropathy following his chemotherapy.

Posttranslational modifications induce autoantibodies with risk prediction capability in patients with small cell lung cancer

Small cell lung cancer (SCLC) elicits the generation of autoantibodies that result in unique paraneoplastic neurological syndromes. The mechanistic basis for the formation of such autoantibodies is largely unknown but is key to understanding their etiology. We developed a high-dimensional technique that enables detection of autoantibodies in complex with native antigens directly from patient plasma. Here, we used our platform to screen 1009 human plasma samples for 3600 autoantibody-antigen complexes, finding that plasma from patients with SCLC harbors, on average, fourfold higher disease-specific autoantibody signals compared with plasma from patients with other cancers. Across three independent SCLC cohorts, we identified a set of common but previously unknown autoantibodies that are produced in response to both intracellular and extracellular tumor antigens. We further characterized several disease-specific posttranslational modifications within extracellular proteins targeted by these autoantibodies, including citrullination, isoaspartylation, and cancer-specific glycosylation. Because most patients with SCLC have metastatic disease at diagnosis, we queried whether these autoantibodies could be used for SCLC early detection. We created a risk prediction model using five autoantibodies with an average area under the curve of 0.84 for the three cohorts that improved to 0.96 by incorporating cigarette smoke consumption in pack years. Together, our findings provide an innovative approach to identify circulating autoantibodies in SCLC with mechanistic insight into disease-specific immunogenicity and clinical utility.

Initial experience in assessing diagnostic utility of conventional and functional imaging (staging CT, PET CT, and MRI Brain/Spine) in suspected cases of paraneoplastic neurological syndrome

Objectives

Radiology receives a large volume of referrals for systemic scans and neuroimaging in suspected cases of paraneoplastic neurological syndrome (PNS) patients. To date, there have been no guidelines to define imaging pathways in diagnosis or surveillance of such patients. This article aims to evaluate diagnostic utility of imaging in detecting positive results as well as ruling out significant pathologies in suspected cases of PNS and strategize vetting requests.

Materials and Methods

Retrospectively evaluated scan records, onconeuronal antibody results of 80 patients (separated into below and over 60s age group) referred with suspected PNS (categorized as classical or probable PNS after neurological assessment). Imaging findings and final diagnoses were classified into three groups: Normal (N), non-neoplastic significant findings (S), and malignancies (M) after evaluating histopathology results/ perioperative findings and treatment notes.

Results

There were ten cases of biopsy-proven malignancies and 18 cases of non-neoplastic significant conditions (predominantly neurological) with malignancies dominating in the elderly age group, demyelinating neurological conditions in below 60s group and patients suspected of classical PNS on neurological evaluation. Staging computed tomography (CT) had 50%, positron emission tomography CT (PETCT) had 80%, sensitivity had 93%, and negative predictive value in ruling out malignancy had 96%. Magnetic resonance of brain and spine was reported abnormal in 68% of finally diagnosed positive cases while only 11% cases demonstrated onconeuronal antibody positivity.

Conclusion

Complete neuroimaging before systemic scans, categorization of referral requests in probable and classical cases of PNS with prioritization of PET in cases of high clinical concern might help in better detection of pathologies and reduce unnecessary CTs.

Anti-CV2/Collapsin Response Mediator Protein 5 (CRMP5) Paraneoplastic Encephalitis Induced by Small Cell Lung Cancer

Paraneoplastic neurological syndrome (PNS) associated with anti-CV2/CRMP5 antibodies is a rare entity that can present in various clinical manifestations, from encephalitis to chorea, depending on the brain region involved. We report a case of an elderly person with small cell lung cancer who presented with PNS encephalitis associated with anti-CV2/CRMP5 antibodies which were confirmed on immunological analysis.

Paraneoplastic neurological syndrome caused by cystitis glandularis: A case report and literature review

BACKGROUND

Paraneoplastic neurological syndrome (PNS) is an unusual event. PNS caused by cystitis glandularis (CG) or a bladder tumor is extremely rare; hence, missed diagnosis or misdiagnosis can easily occur. To date, approximately 21 cases have been reported in PubMed.

CASE SUMMARY

We report a case of PNS caused by CG and describe the clinical and imaging features. The main clinical feature was advanced cognitive impairment, and early clinical features were memory impairment, decreased computational ability, and abnormal behavior. Later clinical features were dementia, vomiting, inability to eat and walk, urinary incontinence, and hematuria. Imaging features on cranial magnetic resonance imaging were diffuse white matter lesions. Paraneoplastic tumor markers were normal. A total abdominal computed tomography scan showed multiple thickened areas on the bladder wall with local prominence. Cystoscopy revealed a volcanic protuberance on the posterior wall of the bladder with a diameter of 6 cm and no pedicle. The postoperative pathological diagnosis was CG. The patient recovered well following resection of CG. PNS cases caused by previous bladder tumors can be retrieved from PubMed to describe the clinical signs and prognosis of PNS.

CONCLUSION

The main clinical feature of PNS caused by CG was dementia, and the imaging features were diffuse cerebral white matter lesions. Resection of CG lesions is the fundamental treatment for PNS induced by CG. This case highlights the importance of etiological treatment.

SOX-1 antibodies in a patient with Crohn's disease: a case report

BACKGROUND

The anti-SOX-1 antibodies have been mainly associated with Lambert-Eaton Myasthenic Syndrome (LETMS) and Small-Cell Lung Cancer (SCLC). In this report, we describe the interesting case of a patient with serum anti-SOX-1 antibodies and Crohn's Disease (CD) with ensuing neurological symptoms.

CASE PRESENTATION

A Caucasian 67-year-old female was admitted to the Emergency Department with seizures, vertigo, emesis, nausea, postural instability and recurrent falls, over a period of 10 days. She had been affected by Crohn's Disease since 1991. A CT scan failed to detect any ischemic or haemorrhagic lesion. A brain MRI revealed signs of leukoencephalopathy. Western blot analysis of her serum revealed a high titre of the onconeural antibody anti-SOX1, consistent with a neurological, cerebellar type, paraneoplastic syndrome. In spite of multiple efforts to unmask a possible underlying malignancy, no neoplastic lesion cropped up during hospitalization. Her clinical conditions progressively deteriorated, up to respiratory failure; a few days later she died, due to ensuing septic shock and Multiple Organ Failure.

CONCLUSIONS

Our experience may usher and reveal a new role of anti-neural antibodies, so far reckoned an early indicator of associated malignancy, suggesting that neurological syndromes associated with such antibodies may complicate also chronic Gastrointestinal (GI) diseases. As of now, testing for anti-neuronal antibodies appeared unnecessary within the diagnostic assessment of gastroenterological disorders, which may lead to overlooking incident neurologic autoimmune diseases. Further exploration of such research hypothesis in clinical grounds appears intriguing.

Opsoclonus-myoclonus syndrome associated with neuroblastoma: Insights into antitumor immunity

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disorder. Half of these cases occur in children with neuroblastoma. Neuroblastoma patients with OMS usually have better oncological outcomes than those without OMS even after stratification by tumor stage and age, indicating that factors mediating OMS may also inhibit tumor cell proliferation. Although the mechanisms underlying OMS remain undefined, the cytokines and lymphocytes alterations in the cerebrospinal fluid support the concept that it is a pattern of neuroinflammation due to an autoimmune effect. The presence of lymphoid follicles consisting of follicular dendritic cells, CD20⁺ B lymphocytes, CD3⁺ T lymphocytes, and CD68⁺ macrophages in the tumor microenvironment in OMS-associated neuroblastoma support the autoimmune nature of this disorder. This review focuses on the clinical and genetic features of OMS-associated neuroblastoma, and we update readers on immune features of neuroblastoma with or without OMS to gain insights into antitumor immunity as it relates to tumor biology and prognosis.

Oncologic emergencies and urgencies: A comprehensive review

Patients with advanced cancer generate 4 million visits annually to emergency departments (EDs) and other dedicated, high-acuity oncology urgent care centers. Because of both the increasing complexity of systemic treatments overall and the higher rates of active therapy in the geriatric population, many patients experiencing acute decompensations are frail and acutely ill. This article comprehensively reviews the spectrum of oncologic emergencies and urgencies typically encountered in acute care settings. Presentation, underlying etiology, and up-to-date clinical pathways are discussed. Criteria for either a safe discharge to home or a transition of care to the inpatient oncology hospitalist team are emphasized. This review extends beyond familiar conditions such as febrile neutropenia, hypercalcemia, tumor lysis syndrome, malignant spinal cord compression, mechanical bowel obstruction, and breakthrough pain crises to include a broader spectrum of topics encompassing the syndrome of inappropriate antidiuretic hormone secretion, venous thromboembolism and malignant effusions, as well as chemotherapy-induced mucositis, cardiomyopathy, nausea, vomiting, and diarrhea. Emergent and urgent complications associated with targeted therapeutics, including small molecules, naked and drug-conjugated monoclonal antibodies, as well as immune checkpoint inhibitors and chimeric antigen receptor T-cells, are summarized. Finally, strategies for facilitating same-day direct admission to hospice from the ED are discussed. This article not only can serve as a point-of-care reference for the ED physician but also can assist outpatient oncologists as well as inpatient hospitalists in coordinating care around the ED visit.

Evaluation of antineuronal antibodies and 8-OHdG in mothers of children with autism spectrum disorder: a case-control study

OBJECTIVE

The purpose of our study was to investigated the anti-Yo, anti-Hu, anti-Ri, anti-amphiphysin antibody levels and 8-OHdG in mothers of children with autism.

METHODS

This study included 60 participants, 33 of whom were healthy mothers of 3-12-year-old children diagnosed with autism spectrum disorder (ASD) and the 27 others who constituted the control group, were healthy mothers with age-matched healthy children. Two groups were examined for plasma anti-Yo, anti-Hu, anti-amphiphysin and anti-Ri antibodies and, 8-OHdG levels. The participants were asked to accomplish a sociodemographic data form. The severity of ASD symptoms was evaluated according to the Childhood Autism Rating Scale (CARS).

RESULTS

Anti-amphiphysin antibody levels and anti-Ri antibody positivity were significantly higher in the case group (p = 0.001; p = 0.027, respectively). The two groups did not significantly differ in terms of anti-Yo and anti-Hu antibody levels and in terms of 8-OHdG levels (p = 0.065; p = 0.099; p = 0.490, respectively). The two groups did not significantly differ in terms of sociodemographic data (p > 0.05).

CONCLUSIONS

According to the our study, maternal antineuronal antibodies, such as anti-amphiphysin and anti-Ri, may contribute to the risk of childhood autism. Studies with larger samples are needed.KEY POINTSMaternal factors associated with autism should be investigated in order to create early diagnosis and treatment opportunities for autism.Based on the importance of immunological and cerebellar pathologies in autism aetiology, we aimed to investigate antineuronal antibodies in mothers of children with autism.Maternal antineuronal antibodies, such as anti-amphiphysin and anti-Ri, may contribute to the risk of childhood autism.High anti-amphiphysin antibody levels in mothers of children with autism may also occur against the amphiphysin in the structure of the SrGAP3 gene, which is associated with autism.

Coexistence of anti-SOX1 and anti-GABAB receptor antibodies with paraneoplastic limbic encephalitis presenting with seizures and memory impairment in small cell lung cancer: A case report

Purpose

Paraneoplastic neurological syndromes associated with autoantibodies are rare diseases that cause abnormal manifestations of the nervous system. Early diagnosis of paraneoplastic neurological syndromes paves the way for prompt and efficient therapy.

Case report

we reported a 56-year-old man presenting with seizures and rapidly progressive cognitive impairment diagnosed as paraneoplastic limbic encephalitis (PLE) with anti-SRY-like high-mobility group box-1 (SOX-1) and anti-γ-aminobutyric acid B (GABAB) receptor antibodies and finally confirmed by biopsy as small cell lung cancer (SCLC). At the first admission, brain magnetic resonance imaging (MRI) showed no abnormal signal in bilateral hippocampal regions and no abnormal enhancement of enhanced scan. The serum anti-GABAB receptor antibody was 1:100 and was diagnosed as autoimmune encephalitis (AE). The computed tomography (CT) scans of the chest showed no obvious tumor signs for the first time. Although positron emission tomography-computed tomography (PET-CT) revealed hypermetabolism in the para mid-esophageal, the patient and his family declined to undertake a biopsy. The patient improved after receiving immunoglobulin, antiepileptic therapy, and intravenous methylprednisolone (IVMP) pulse treatment. However, after 4 months, the symptoms reappeared. Brain MRI revealed abnormal signals in the hippocampal regions. Reexamination of the cerebral fluid revealed anti-GABAB receptor and anti-SOX-1 antibodies, which contributed to the diagnosis of PLE. SCLC was found in a para mid-esophageal pathological biopsy. Antiepileptic medications and immunoglobulin were used to treat the patient, and the symptoms were under control.

Conclusion

Our findings increase the awareness that patients with limbic encephalitis with cognitive dysfunction and epileptic seizures should be enhanced to detect latent malignancy. Our case also highlights the importance of anti-SOX1 antibodies in the detection of underlying neoplasm, particularly SCLC. Our findings raise awareness of the cognitive impairment seen by patients with limbic encephalitis.

Evaluation of the Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes in China

Background

Recently, the paraneoplastic neurologic syndrome (PNS) diagnostic criteria have received a major update with a new score system over the past 16 years. We aimed to evaluate the diagnostic performance and clinical utility in China.

Methods

An eligible cohort of 113 Chinese patients diagnosed with PNSs from the Second Affiliated Hospital School of Medicine Zhejiang University and published data were enrolled retrospectively. Data including clinical phenotype, antibody type, the presence of cancer, and duration of follow-up were reviewed and re-evaluated to classify the diagnostic levels for the 2004 and 2021 PNS criteria. The performances of these 2 criteria were compared. The critical parameters of antibody and cancer for the updated criteria were further explored.

Results

The cohort consisted of 69 males and 44 females with a median age of 60 years. Limbic encephalitis (23, 20.4%), anti-Hu antibody (32, 28.3%), and small-cell lung cancer (32, 28.3%) were the most common clinical phenotype, detected antibody, and concomitant cancer, respectively. A total of 97 (85.8%) patients were diagnosed with definite PNS according to the 2004 criteria: only 42.3% (41/97) fulfilled the 2021 criteria, while the remaining 40, 14, and 2 re-diagnosed with probable PNS, possible PNS, and non-PNS. The requirement of cancers consistent with antibody and phenotype increased the specificity and thus greatly enhanced the accuracy of the 2021 criteria.

Conclusion

The updated criteria for PNS emphasized the consistency between cancer phenotype and antibody and showed a better diagnostic value. A better diagnostic yield could benefit disease management.

Anti-Yo-Associated Paraneoplastic Cerebellar Degeneration: Case Series and Review of Literature

Anti-Yo-associated paraneoplastic cerebellar degeneration (PCD) syndrome is a very rare condition that is most commonly associated with breast and gynecologic cancers. Those cases associated with breast cancer tend to be human epidermal growth factor receptor 2 (HER2)-positive, though the reason for this correlation is unknown. Most commonly, the neurologic symptoms of the PCD syndrome predate the patient’s cancer diagnosis. Thus, prompt diagnosis of PCD is essential to allow for early treatment of the neurologic symptoms and the underlying malignancy. However, the prognosis is very poor for the anti-Yo-associated paraneoplastic syndrome, since neurologic damage is usually rapid and irreversible. Further progression may be stopped with appropriate treatment of cancer, but existing neurologic deficits at the time of diagnosis are usually permanent. Steroids, plasma exchange, and rituximab are commonly used treatments, though these have had mixed to poor results.

Anti-Ma2 Antibody-Associated Paraneoplastic Neurological Syndromes: A Pilot Study

Paraneoplastic neurologic syndromes (PNSs) are a heterogeneous group of disorders caused by the remote effects of cancer with immune-mediated pathogenesis. Anti-Ma2 antibody was defined as one of the well-characterized onconeural antibodies that could help establish a definite PNS diagnosis. We aimed to report and explore patients with anti-Ma2 antibody-associated paraneoplastic neurologic syndrome (Ma2-PNS) who frequently exhibit sensorimotor neuropathy (SMN) using a new method of factor analysis of mixed data (FAMD). Clinical data from a case series of eight patients with definite diagnoses were retrospectively reviewed. FAMD conducted further analyses with a comprehensive visualization in R software. Our cohort, with a predominance of females (5/8), presented more frequently with SMN (4/8), followed by limbic encephalitis (LE) (3/8). Two patients with LE were found to have a testicular germ-cell tumor and a thymoma, respectively. In addition, a patient who developed chronic SMN was diagnosed with multiple myeloma (MM) involving multiple organs. FAMD exhibited the overall features into a two-dimensional coordinate and located each individual into their corresponding position with high relevance. It provided a clue for determining their potential relationships and predictors. Our findings indicated that Ma2-PNS could frequently involve the peripheral nervous system, MM might be one of its associated cancers with a presentation of chronic SMN, and FAMD might be a clinically valuable tool.

Opticoneuromyelitis associated with melanoma. Case report

This article presents a clinical review of a patient with an extremely rare assotiation of opticoneuromyelitis and skin melanoma. The paper noted the typical clinical and neuroimaging signs of opticoneuromyelitis and the rare manifestations of myelitic syndrome such as segmental muscle hypertonicity and hand hyperkinesis. The question remains open as to whether these two processes in a patient are linked by a single pathogenesis in the form of a paraneoplastic neurological syndrome or whether two independent diseases are represent there. Two observations of a combination of melanoma and opticoneuromyelitis as a manifestation of the paraneoplastic syndrome have been analysed in the literature. The article highlights the difficulties in the treatment of this patient, as the immunomodulatory therapy used for both diseases has a different vectorial focus. Immunosuppression is recommended for the treatment of opticoneuromyelitis, while immune activation is recommended for melanoma.

A case of non-small cell lung cancer presenting anti-amphiphysin antibody-positive paraneoplastic neurological syndrome

Paraneoplastic neurological syndrome (PNS) is associated with malignancies, such as small-cell lung cancer. However, patients with non-small cell lung cancer (NSCLC) rarely develop PNS. We herein report a 72-year-old man with NSCLC who developed disturbance of consciousness on the day of initiation of treatment with an immune checkpoint inhibitor. Blood test results revealed anti-amphiphysin (AMPH) antibody positively, leading to the diagnosis of PNS. The disturbance of consciousness was improved with intravenous administration of steroid and immunoglobulin. To our knowledge, this is the first report of anti-AMPH antibody-positive PNS in a patient with NSCLC.

AQP4-IgG positive paraneoplastic NMOSD: A case report and review

INTRODUCTION

Neuromyelitis optica spectrum disorder (NMOSD; also known as Devic syndrome) is a clinical syndrome of central nervous system characterized by immune mediated attacks of acute optic neuritis and myelitis. Paraneoplastic neurological syndrome is a group of nervous system disorders resulting from the remote immune effects of malignant neoplasm. NMOSD occurs mostly in young people, and tumor is not a common cause, especially recurrent tumor.

METHODS

We reported a case of a 59-year-old man who developed anti-aquaporin-4 IgG positive longitudinally extensive myelitis. We also summarized and analyzed previously reported cases of paraneoplastic NMOSD.

RESULTS

Among these 43 patients, 88.4% patients are female. The largest number of patients is between 60 and 69 years old. Breast cancer and lung cancer are the most common types. The most common lesions were located in the cervicothoracic region with patchy gadolinium enhancement. The existing treatment can only delay rather than stop the progress of the disease.

CONCLUSION

It is necessary to perform tumor screening in patients with NMOSD, especially patients over 50 years.

Chronic intestinal pseudo-obstruction: diagnostic and prognostic utility of ANNA-1/Anti-Hu onconeural antibodies

A 65-year-old woman who, in the context of dyspepsia and dismotility, was diagnosed with chronic intestinal pseudo-obstruction (CIPO) in small cell lung carcinoma (SCLC). In spite of a remarkable tumor response after the combination of chemotherapy and immunotherapy, an intestinal sepsis led to the patient's sudden death.

Diseases which cause generalized peripheral neuropathy: a systematic review

PURPOSE

Peripheral autonomic neuropathy, including enteric neuropathy, may be subtle and unrecognized for several years. Diagnosis of enteric neuropathy demands complicated examinations such as full-thickness bowel biopsy. We hypothesized that knowledge about simultaneous occurrence of different types of neuropathy would lead to faster recognition and diagnosis of autonomic/enteric neuropathy. The aim of the present systematic review was to increase the awareness of disease groups causing autonomic and enteric neuropathy along with sensorimotor neuropathy.

METHODS

A systematic search strategy was used in PubMed, Embase and Web of Science. First, 4978 articles were identified. Review of titles/abstracts rendered exclusion of animal studies, articles not written in English or full-length, case reports, conference abstracts and duplicates until 357 articles remained. The full-length evaluation resulted in 35 studies (27 non-systematic reviews) which described objectively verified peripheral autonomic, enteric and sensorimotor neuropathy within the same disease.

RESULTS

Diabetes is the most common disease in society rendering generalized peripheral neuropathy. Accumulation of tissue deposits in amyloidosis, Lewy body disorders and sarcoidosis lead to widespread peripheral neuropathy. Several autoimmune disorders such as systemic sclerosis and primary Sjögren's syndrome present themselves with neuropathy. Paraneoplastic neuropathy may appear prior to symptoms from the malignancy. Both the infection per se, as well as the autoimmune response to the infection, i.e., Guillain-Barré syndrome, may lead to widespread peripheral neuropathy. Hereditary disorders with disturbed metabolism lead to intermittent attacks of neuropathy.

CONCLUSIONS

The major causes of generalized peripheral neuropathy are diabetes, diseases with tissue deposits, autoimmunity, infections, malignancy and metabolic diseases.

[Paraneoplastic sensorimotor neuropathy with anti-Hu antibody associated with gallbladder carcinoma]

A 78-year-old woman experienced gait disturbance. She became unable to walk within a month. On admission, her cranial nerves were normal. She had motor weakness in the arms and legs, dysesthesia of the peripheral extremities, impaired deep sensation in the legs, and hyporeflexia in the arms and legs. She was initially diagnosed with Guillain-Barré syndrome; therefore, she was treated with intravenous immunoglobulin therapy and steroid mini-pulse therapy, however improvements of her neurological deficits were minimal. Anti-Hu antibody was positive in serum and gallbladder carcinoma was detected. She was treated with chemotherapy but neurological symptoms worsened progressively. Gallbladder carcinoma can rarely cause anti-Hu associated paraneoplastic sensorimotor neuropathy.

Clinical characteristics of paraneoplastic neurological syndrome related to different pathological lung cancers

Background

Paraneoplastic syndrome is a distant effect caused by malignant tumors, which is related to the production of cellular immune response. The nervous system is the most common involved system of paraneoplastic syndrome. It is easy to be misdiagnosed. Lung cancer is the most common cancer relating to paraneoplastic neurological syndrome (PNS).

Method

This study retrospectively analyzed clinical data of patients with the combination of PNS and lung cancer between January 2005 and March 2021 at Qilu Hospital of Shandong University, China.

Results

A total of 111 patients were diagnosed with lung cancer complicated with PNS. A total of 95 (85.6%) cases had neurological symptoms as the first symptom. Sixty‐three cases had the pathological results. A total of 43 (68.3%) of small cell lung cancer (SCLC) were diagnosed. PNS patients diagnosed with SCLC included peripheral neuropathy (15 cases, 34.9%). PNS patients diagnosed with non‐small cell lung cancer (NSCLC) included peripheral neuropathy (6 cases, 30%) and limbic encephalitis (6 cases, 30%). Anti‐Hu is popular in patients with SCLC (12 cases, 42.9%) and NSCLC (6 cases, 40%).

Conclusions

Most patients with PNS had neurological symptoms as the first symptom. It was more common in males. It had a higher incidence in SCLC. Peripheral neuropathy was the most common PNS associated with SCLC, followed by Lambert‐Eaton syndrome. Peripheral neuropathy and limbic encephalitis were the most common PNS associated with NSCLC. Anti‐Hu is the most common antibodies both in SCLC and NSCLC. Tumor markers do not have significant difference between different pathological types.

Chronic Intestinal Pseudo-Obstruction Due to Incidentally Found Thymoma

Chronic intestinal pseudo-obstruction is a severe gastrointestinal tract disorder mimicking a bowel obstruction with no mechanical causes. Our patient presented with bowel obstruction symptoms, and a thymoma was incidentally found during the diagnostic workup. After failing conservative management, the patient underwent exploratory laparotomy that showed negative results for a mechanical cause of obstruction. Laboratory workup was suggestive of paraneoplastic syndrome, and the patient was started on steroids and pyridostigmine course with symptom resolution. Thus, in patients with chronic intestinal pseudo-obstruction, paraneoplastic syndrome should be considered in the differential diagnosis.

Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes

Objective

The contemporary diagnosis of paraneoplastic neurologic syndromes (PNSs) requires an increasing understanding of their clinical, immunologic, and oncologic heterogeneity. The 2004 PNS criteria are partially outdated due to advances in PNS research in the last 16 years leading to the identification of new phenotypes and antibodies that have transformed the diagnostic approach to PNS. Here, we propose updated diagnostic criteria for PNS.

Methods

A panel of experts developed by consensus a modified set of diagnostic PNS criteria for clinical decision making and research purposes. The panel reappraised the 2004 criteria alongside new knowledge on PNS obtained from published and unpublished data generated by the different laboratories involved in the project.

Results

The panel proposed to substitute “classical syndromes” with the term “high-risk phenotypes” for cancer and introduce the concept of “intermediate-risk phenotypes.” The term “onconeural antibody” was replaced by “high risk” (>70% associated with cancer) and “intermediate risk” (30%–70% associated with cancer) antibodies. The panel classified 3 levels of evidence for PNS: definite, probable, and possible. Each level can be reached by using the PNS-Care Score, which combines clinical phenotype, antibody type, the presence or absence of cancer, and time of follow-up. With the exception of opsoclonus-myoclonus, the diagnosis of definite PNS requires the presence of high- or intermediate-risk antibodies. Specific recommendations for similar syndromes triggered by immune checkpoint inhibitors are also provided.

Conclusions

The proposed criteria and recommendations should be used to enhance the clinical care of patients with PNS and to encourage standardization of research initiatives addressing PNS.

Paraneoplastic Sensory Polyneuropathy Related to Anti-PD-L1-including Anticancer Treatment in a Patient with Lung Cancer

Paraneoplastic neurological syndromes (PNS), such as sensory polyneuropathy, are rare, and serum neuronal antibodies that are used for diagnosing this syndrome are occasionally positive. Similarly, neurological immune-related adverse events due to immune checkpoint inhibitors (ICIs) are also rare. However, their etiologies and the relationship between them remain unclear. We herein report a patient with suspected small cell lung cancer who showed sensory polyneuropathy after treatment with atezolizumab in combination with cytotoxic agents (carboplatin and etoposide) and was doubly positive for serum anti-Hu and anti-SOX-1 antibodies. Treatment with ICI and cytotoxic agents may sometimes lead to the development of PNS.

Paraneoplastic ganglioradiculoneuritis in a cat with a plasma cell tumour

Case summary

An 8-year-old neutered female domestic longhair cat was presented for investigation of a 48 h history of lethargy and pelvic limb ataxia. MRI of the spinal cord and vertebral column (C1 to sacrum) and brain was unremarkable. Lumbar cerebrospinal fluid analysis revealed pleocytosis and increased protein concentration. Thoracic radiographs and abdominal ultrasound were unremarkable. Anti-inflammatory doses of prednisolone were administered. Clinical deterioration occurred over the following 2 days, with the development of lower motor neuron deficits in both thoracic limbs. On repetition of the MRI, bilateral enlargement, T2-weighted hyperintensity, and marked contrast enhancement of the C7, C8 and T1 nerve roots, spinal nerves and brachial plexuses were observed. Infectious disease testing was negative. An immune-mediated inflammatory process was suspected and immunosuppressive doses of prednisolone were commenced. The clinical signs improved transiently, but marked deterioration occurred after 2 weeks. The patient was euthanased and a post-mortem examination was performed. A lymphocytic inflammatory infiltrate was detected in the C7, C8 and T1 nerve roots and dorsal root ganglia, and neoplastic plasma cells were identified in multiple organs. A diagnosis of non-cutaneous extramedullary plasmacytoma with multiorgan involvement and paraneoplastic ganglioradiculoneuritis was reached.

Relevance and novel information

Paraneoplastic ganglioradiculoneuritis in association with a plasma cell neoplasia has not been previously reported in the cat and should be considered as a differential diagnosis for cats with clinical or imaging evidence of an inflammatory process affecting the nerve roots, spinal nerves or brachial plexuses.

Bilateral facial nerve palsy associated with amphiphysin antibody in metastatic breast cancer: a case report

Background

Paraneoplastic neurological syndrome is an immune-mediated phenomenon where antibodies from tumor cells are produced against neuronal proteins. Amphiphysin antibody is an onconeural antibody linked to the diagnosis of breast cancer and small-cell lung cancer. It is uncommon and typically associated with stiff-person syndrome, of which 90% of patients are eventually diagnosed with breast cancer.

Case presentation

We present a case of a 47-year-old Caucasian woman with metastatic hormone receptor-positive breast cancer who developed bilateral facial nerve palsy while on treatment with nab-paclitaxel. The patient was found to have anti-amphiphysin antibody in the serum and cerebrospinal fluid. She was treated with methylprednisolone and intravenous immunoglobulin, which resulted in partial improvement in her facial nerve palsy.

Conclusions

This case highlights a rare presentation of bilateral facial nerve palsy that likely related to paraneoplastic syndrome associated with the presence of anti-amphiphysin antibody.