Treatment of paraneoplastic cerebellar degeneration

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.

Ovarian mass Presenting as Paraneoplastic cerebellar degeneration with peripheral neuropathy and anti-Yo antibody

Paraneoplastic neurological syndromes (PNS) are a group of disorders with diverse neurological manifestations that are observed in patients with various types of cancer. Any portion of the nervous system can be affected by these syndromes, which are brought on by processes other than metastasis, direct tumour spread or chemotherapy side effects. An immune-mediated attack on the cerebellar Purkinje cells and consequent cerebellar symptoms define paraneoplastic cerebellar degeneration(PCD), a subtype of the PNS. Axonal or demyelinating paraneoplastic peripheral neuropathies are both possible. Here, we describe the case of a middle-aged woman who presented with subacute-onset cerebellar symptoms and peripheral neuropathy, was discovered to have a positive anti-Yo antibody, and was later detected to have an ovarian mass. This case illustrates the significance of considering a paraneoplastic aetiology in patients with otherwise unexplained neurological manifestations and initiating an appropriate workup and early treatment for the primary malignancy.

Paraneoplastic cerebellar and brainstem disorders

Paraneoplastic cerebellar and brainstem disorders are a heterogeneous group that requires prompt recognition and treatment to help prevent irreversible neurologic injury. Paraneoplastic cerebellar degeneration is best characterized by Yo antibodies in patients with breast or ovarian cancer. Tr (DNER) antibodies in patients with Hodgkin lymphoma can also present with a pure cerebellar syndrome and is one of the few paraneoplastic syndromes found with hematological malignancy. Opsoclonus-myoclonus-ataxia syndrome presents in both pediatric and adult patients with characteristic clinical findings. Other paraneoplastic brainstem syndromes are associated with Ma2 and Hu antibodies, which can cause widespread neurologic dysfunction. The differential for these disorders is broad and also includes pharmacological side effects, infection or postinfectious processes, and neurodegenerative diseases. Although these immune-mediated disorders have been known for many years, mechanisms of pathogenesis are still unclear, and optimal treatment has not been established.

Immunotherapies for the Effective Treatment of Primary Autoimmune Cerebellar Ataxia: a Case Series

Primary autoimmune cerebellar ataxia (PACA) is an idiopathic sporadic cerebellar ataxia that is thought to be immune-mediated but lacks biomarkers or a known cause. Here, we report two cases of immune-mediated cerebellar ataxia that responded favorably to immunotherapy, in which tissue-based indirect immunofluorescence test for serum or cerebrospinal fluid (CSF) samples yielded positive results. Case 1 was a 78-year-old man who presented with subacute progressive gait ataxia with truncal instability and dysarthria in response to steroids. Case 2 was a 62-year-old man who presented with relapses and remissions of acute progressive cerebellar ataxia occurring 1-2 times per year. Despite a favorable response to steroid treatment, he relapsed repeatedly in the absence of long-term immunosuppression. In the case of "idiopathic" cerebellar ataxia, immune-mediated causes should be investigated, and immunotherapy may have therapeutic effects.

Treatable Ataxias: How to Find the Needle in the Haystack?

Treatable ataxias are a group of ataxic disorders with specific treatments. These disorders include genetic and metabolic disorders, immune-mediated ataxic disorders, and ataxic disorders associated with infectious and parainfectious etiology, vascular causes, toxins and chemicals, and endocrinopathies. This review provides a comprehensive overview of different treatable ataxias. The major metabolic and genetic treatable ataxic disorders include ataxia with vitamin E deficiency, abetalipoproteinemia, cerebrotendinous xanthomatosis, Niemann-Pick disease type C, autosomal recessive cerebellar ataxia due to coenzyme Q10 deficiency, glucose transporter type 1 deficiency, and episodic ataxia type 2. The treatment of these disorders includes the replacement of deficient cofactors and vitamins, dietary modifications, and other specific treatments. Treatable ataxias with immune-mediated etiologies include gluten ataxia, anti-glutamic acid decarboxylase antibody-associated ataxia, steroid-responsive encephalopathy associated with autoimmune thyroiditis, Miller-Fisher syndrome, multiple sclerosis, and paraneoplastic cerebellar degeneration. Although dietary modification with a gluten-free diet is adequate in gluten ataxia, other autoimmune ataxias are managed by short-course steroids, plasma exchange, or immunomodulation. For autoimmune ataxias secondary to malignancy, treatment of tumor can reduce ataxic symptoms. Chronic alcohol consumption, antiepileptics, anticancer drugs, exposure to insecticides, heavy metals, and recreational drugs are potentially avoidable and treatable causes of ataxia. Infective and parainfectious causes of cerebellar ataxias include acute cerebellitis, postinfectious ataxia, Whipple's disease, meningoencephalitis, and progressive multifocal leukoencephalopathy. These disorders are treated with steroids and antibiotics. Recognizing treatable disorders is of paramount importance when dealing with ataxias given that early treatment can prevent permanent neurological sequelae.

Paraneoplastic Ataxia: Antibodies at the Forefront Have Become Routine Biomarkers

Paraneoplastic cerebellopathies are immune-mediated disorders targeting primarily the cerebellar circuitry, often presenting in a subacute course. The syndrome often develops before the cancer. Therefore, its identification often leads secondarily to a diagnosis of cancer, a critical step to stabilize symptoms. Two categories of antibodies have been identified these last 30 years: (a) onconeuronal antibodies which are directed against intracellular antigens, and (b) antibodies which are directed against synaptic and cell surface proteins. These latter impact on the location and function of the antigens, causing a genuine neuronal dysfunction. Appropriate and fast tumor screening has emerged as a recommendation facing a subacute cerebellar syndrome suspected to be paraneoplastic. Search for antibodies is now a milestone for the diagnosis.

Therapeutic Plasma Exchange: For Cancer Patients

Therapeutic plasma exchange is used as a trial method for the treatment of cancer patients. Therapeutic plasma exchange uses in vitro technology to remove pathogenic factors in the plasma, returning the replacement and remaining components to the patient to facilitate cure. In the effort to explore new methods of cancer treatment, the introduction of therapeutic plasma exchange brings new hope for cancer treatment; however, the current evidence supporting therapeutic plasma exchange is controversial, and most of the evidence comes from observational studies, lacking large prospective randomized trials. Therefore, this review attempts to focus on the main indications of therapeutic plasma exchange for the treatment of tumors and their complications, including hematological tumors (multiple myeloma cast nephropathy and hyperviscosity syndrome), nervous system tumors (myasthenia gravis associated with thymoma, paraneoplastic neurological syndrome, Lambert–Eaton myasthenia syndrome, and anti-N-methyl-D-aspartate receptor encephalitis), overdose of chemotherapy drugs. In addition, the issues of side-effects and safety in the use of therapeutic plasma exchange are also discussed. However, well-designed prospective trials are needed to better define the role of therapeutic plasma exchange in cancer.

Clinical features and outcome of patients with autoimmune cerebellar ataxia evaluated with the Scale for the Assessment and Rating of Ataxia

BACKGROUND AND PURPOSE

This study was undertaken to assess the long-term outcome of patients with paraneoplastic and non paraneoplastic autoimmune cerebellar ataxia (ACA) using the Scale for the Assessment and Rating of Ataxia (SARA).

METHODS

Patients with subacute cerebellar ataxia admitted to our institution between September 2012 and April 2020 were prospectively recruited. Serum and/or cerebrospinal fluid was tested for neural autoantibodies by indirect immunofluorescence on mouse brain, cell-based assays, and radioimmunoassay. SARA and modified Rankin Scale (mRS) score were employed to assess patients' outcome.

RESULTS

Fifty-five patients were recruited, of whom 23 (42%) met the criteria for cerebellar ataxia of autoimmune etiology. Neural autoantibodies were detected in 22 of 23 patients (Yo-immunoglobulin G [IgG], n = 6; glutamic acid decarboxylase 65-IgG, n = 3; metabotropic glutamate receptor 1-IgG, n = 2; voltage-gated calcium channel P/Q type-IgG, n = 2; Hu-IgG, n = 1; glial fibrillary acidic protein-IgG, n = 1; IgG-binding unclassified antigens, n = 7). Thirteen patients were diagnosed with paraneoplastic cerebellar syndrome (PCS) and 10 with idiopathic ACA. All patients received immunotherapy. Median SARA score was higher in the PCS group at all time points (p = 0.0002), while it decreased significantly within the ACA group (p = 0.049) after immunotherapy. Patients with good outcome (mRS ≤ 2) had less neurological disability (SARA < 15) at disease nadir (p = 0.039) and presented less frequently with paraneoplastic neurological syndrome (p = 0.0028). The univariate linear regression model revealed a good correlation between mRS and SARA score both at disease onset (p < 0.0001) and at last follow-up (p < 0.0001). SARA score < 11 identified patients with good outcome.

CONCLUSIONS

Patients with idiopathic ACA significantly improved after immunotherapy. SARA score accurately reflects patients' clinical status and may be a suitable outcome measure for patients with ACA.

Neurological Autoimmunity Associated With Homer-3 Antibody: A Case Series From China

BACKGROUND AND OBJECTIVE

To present 6 new cases with Homer-3 antibodies that expand their clinical spectra and to evaluate the effect of immunotherapy.

METHODS

Patients with suspected autoimmune cerebellar disorder were tested for rare autoimmune cerebellar ataxia (ACA) antibodies (anti-Tr(DNER)/Zic4/ITPR1/Homer-3/NCDN/PKCγ/PCA-2/AP3B2/mGluR1/ATP1A3 antibodies) using both cell-based and tissue-based assays. Patients with positive serum or CSF results who were diagnosed with ACA were registered and followed up. This study reports and analyzes cases with Homer-3 antibodies.

RESULTS

Of the serum and CSF samples of 750 patients tested, 6 were positive for Homer-3 antibodies. All manifested subacute or insidious-onset cerebellar ataxia. Furthermore, 2 patients each exhibited encephalopathy, myeloradiculopathy, REM sleep behavior disorder, and autonomic dysfunction. Brain magnetic resonance images were normal (n = 1) or revealed cerebellar atrophy (n = 1), cerebellum and pons atrophy with the hot cross bun sign (n = 2), and bilateral cerebral abnormalities (n = 2). Definite leukocytosis was identified in the CSF of 2 patients, protein concentration elevation was observed in the CSF of 1 patient, and oligoclonal bands were present in 2 patients. All patients received immunotherapy, including corticosteroid, IV immunoglobulin, plasma exchange, and mycophenolate mofetil, after which the residual disability was still severe (modified Rankin Scale score ≥3 at the last follow-up in 4 patients and final Scale for the Assessment and Rating of Ataxia scores of 12-29), although 4 patients partially improved and 1 patient stabilized. The remaining 1 patient continued to deteriorate after repeated immunotherapy. Two patients relapsed.

DISCUSSION

Disorders associated with Homer-3 antibody can mimic multiple system atrophy with cerebellar features in both clinical and radiologic aspects. Accurate identification of autoimmune-mediated cases is critical. Timely, comprehensive immunotherapy is warranted, given the possibility of long-term clinical benefit.

Acute-onset paraneoplastic cerebellar degeneration secondary to neuroendocrine carcinoma with atypical prognosis: a case report

Paraneoplastic cerebellar degeneration (PCD) is a neurological syndrome that is likely caused by tumor-induced autoimmunity against the cerebellum. Neuroendocrine carcinoma (NEC) is a type of neoplasm with high-grade malignant histology and biological behavior. The prognosis for both PCD and NEC is typically poor. We report a case of PCD secondary to metastatic NEC in the lymph nodes, with an unknown primary origin. The case presented acute cerebellar manifestations with typical neuroimaging findings, but with atypical prognosis after lymph node dissection. Neurological symptoms can provide clues to potential tumors, and early antitumor treatment may have contributed to the positive prognosis of PCD secondary to NEC in the present case.

Neurological complications of pediatric cancer

Both the onset of various malignancies as well as the treatment of cancer can lead to neurologic symptoms which can be difficult to diagnose. In this review, we highlight the varied ways in which neurologic sequelae of cancer and its treatment manifest in children. Initial neurologic presentation may be secondary to mass effect or to immune-mediated paraneoplastic syndromes. Treatment effects on the nervous system may arise from surgery, chemotherapy, radiation, or bone marrow transplantation. In addition, the rapidly expanding field of immunotherapies for cancer has generated numerous new approaches to eradicating cancer including monoclonal antibodies, checkpoint inhibitors, and chimeric antigen receptor T cells (CAR-T cells), which have neurologic side effects mediated by immune responses that are also being recognized. Here we review common consult questions to the neurologist and our general approach to these scenarios including altered mental status, headaches, seizures, and sensorimotor complaints, considering the multifactorial nature of each.

Advances in Therapies of Cerebellar Disorders: Immune-mediated Ataxias

The identification of an increasing number of immune mediated ataxias suggests that the cerebellum is often a target organ for autoimmune insults. The diagnosis of immune mediated ataxias is challenging as there is significant clinical overlap between immune mediated and other forms of ataxia. Furthermore the classification of immune mediated ataxias requires further clarification particularly for those ataxias where no specific antigenic trigger and associated antibodies have been identified. Recognition of immune mediated ataxias remains imperative as therapeutic interventions can be effective, although given the relative rarity of this entity, large-scale treatment trials may not be feasible. This review will discuss advances in therapies for immune mediated ataxias based on what is currently available in the literature.

Paraneoplastic Cerebellar Degeneration Secondary to BRAF Mutant Melanoma Metastasis from an Occult Primary Cancer

Melanoma metastasis from an unknown primary cancer has an incidence of 3.2% among melanoma patients. Furthermore, paraneoplastic neurological syndromes (PNS) are rare, occurring in 1-3% of patients with malignancies. Paraneoplastic cerebellar degeneration (PCD) is one of the classic PNS and is characterized by acute or subacute onset of ataxia and/or presence of onconeural antibodies. A 61-year-old male with ataxia, vertigo, and headache later developed dysarthria, multidirectional nystagmus, hyperactive delirium, auditory hallucinations, psychomotor agitation, and myoclonus. Toxicological, metabolic, infectious, and autoimmune etiologies were assessed and reported negative. An osteolytic lesion was observed in the right iliac crest via computed tomography (CT). A positron emission tomography-CT reported increased fluorodeoxyglucose uptake of a right iliac and right inguinal ganglion. After biopsy of the right inguinal ganglion, a BRAF mutation-positive melanoma metastasis from an occult primary cancer was diagnosed. Dermatologic, ophthalmologic, and endoscopic gastrointestinal assessment did not reveal a primary malignant melanoma. The patient's movement disorders and neuropsychiatric symptoms improved with quetiapine, prednisone, azathioprine, and cyclophosphamide. Oncological management was conducted with MAPK pathway inhibitors (i.e., dabrafenib and trametinib). Movement disorders associated with neuropsychiatric symptoms are complex to diagnose. PNS are rare and often associated with antibodies against neural antigens expressed by the tumor. The case presented above describes a patient with a BRAF-positive malignant melanoma metastasis from an occult primary associated with PCD - to the best of our knowledge, the first reported in the literature.

Revisiting the Clinical Phenomenology of "Cerebellar Tremor": Beyond the Intention Tremor

Tremor is an involuntary, rhythmic, oscillatory movement of a body part. It is a central feature of a range of diseases resulting from pathological changes in the cerebellum. Interestingly, in modern times, the terms "cerebellar tremor" and "intention tremor" are often used synonymously and interchangeably. However, "cerebellar tremor" (i.e., tremors of cerebellar origin) do not always present exclusively as intention tremor. In this article, we comprehensively revisit the clinical phenomenology of tremors observed in various diseases that are based in the cerebellum. By this, we mean diseases for which the cerebellum and its various connections are often seen as playing a central and defining role. These include spinocerebellar ataxias, essential tremor, orthostatic tremor, dystonia, acute cerebellitis, cerebellar tumors, paraneoplastic cerebellar degeneration, and cerebellar strokes. The theme of this article is to highlight, through published data available in the current literature, that the clinical phenomenology of tremor of cerebellar origin is heterogeneous, and it extends beyond that of intention tremor to include postural tremors, kinetic tremor, rest tremor, and orthostatic tremor. This heterogeneity is consistent with the seminal work of Gordon Holmes, in which he described a variety of tremors aside from intention tremor in the setting of cerebellar lesions. In the end, it would seem that the notion that intention tremor is the sole signature of cerebellar lesions is an over-simplification and is not correct. Future studies are warranted to identify and further characterize the heterogeneity of tremors arising from the various cerebellar etiologies.

Paraneoplastic cerebellar degeneration: Yo antibody alters mitochondrial calcium buffering capacity

Aim

Neurodegeneration is associated with dysfunction of calcium buffering capacity and thereby sustained cellular and mitochondrial calcium overload. Paraneoplastic cerebellar degeneration (PCD), characterized by progressive Purkinje neurone degeneration following paraneoplastic Yo antibody internalization and binding to cerebellar degeneration‐related protein CDR2 and CDR2L, has been linked to intracellular calcium homeostasis imbalance due to calbindin D_28k malfunction. Therefore, we hypothesized that Yo antibody internalization affects not only calbindin calcium binding capacity, but also calcium‐sensitive mitochondrial‐associated signalling, causing mitochondrial calcium overload and thereby Purkinje neurone death.

Methods

Immunohistochemically, we evaluated cerebellar organotypic slice cultures of rat brains after inducing PCD through the application of Yo antibody‐positive PCD patient sera or purified antibodies against CDR2 and CDR2L how pharmacologically biased mitochondrial signalling affected PCD pathology.

Results

We found that Yo antibody internalization into Purkinje neurons caused depletion of Purkinje neurone calbindin‐immunoreactivity, cannabinoid 1 receptor over‐activation and alterations in the actions of the mitochondria permeability transition pore (MPTP), voltage‐dependent anion channels, reactive oxygen species (ROS) and Na⁺/Ca²⁺ exchangers (NCX). The pathological mechanisms caused by Yo antibody binding to CDR2 or CDR2L differed between the two targets. Yo‐CDR2 binding did not alter the mitochondrial calcium retention capacity, cyclophilin D‐independent opening of MPTP or activity of NCX.

Conclusion

These findings suggest that minimizing intracellular calcium overload toxicity either directly with cyclosporin‐A or indirectly with cannabidiol or the ROS scavenger butylated hydroxytoluene promotes mitochondrial calcium homeostasis and may therefore be used as future neuroprotective therapy for PCD patients.

Anti-Yo-Associated Paraneoplastic Cerebellar Degeneration Manifesting as Acute Cerebellitis with Posterior Cranial Fossa Hypertension

BACKGROUND

Paraneoplastic cerebellar degeneration (PCD) is a rare complication of some malignant cancers. It is most commonly described in women with gynecologic or breast malignancies; however, there have been reports in other types of cancers. Symptoms include ataxia, dysarthria, and tremors, which could be the first manifestations of an underlying malignancy.

CASE DESCRIPTION

A 50-year-old woman had an acute PCD with anti-Yo antibodies from an underlying breast invasive ductal carcinoma. She presented with intracranial hypertension in the posterior cranial fossa that required an emergent decompressive craniectomy.

CONCLUSIONS

PCD is an uncommon disease that may manifest initially as posterior cranial fossa hypertension and subsequent acute hydrocephalus owing to diffuse cerebellar swelling. To our knowledge, this is the first described case of an anti-Yo PCD that has manifested as acute posterior cranial fossa hypertension owing to diffuse cerebellar edema. Early diagnosis and treatment should be pursued to improve long-term outcomes.

Guidelines for treatment of immune-mediated cerebellar ataxias

Immune-mediated cerebellar ataxias include gluten ataxia, paraneoplastic cerebellar degeneration, GAD antibody associated cerebellar ataxia, and Hashimoto’s encephalopathy. Despite the identification of an increasing number of immune-mediated cerebellar ataxias, there is no proposed standardized therapy. We evaluated the efficacies of immunotherapies in reported cases using a common scale of daily activity. The analysis highlighted the importance of removal of autoimmune triggering factors (e.g., gluten or cancer) and the need for immunotherapy evaluation (e.g., corticosteroids, intravenous immunoglobulin, immunosuppressants) and adaptation according to each subtype.

Treatable causes of cerebellar ataxia

The cerebellar ataxia syndromes are a heterogeneous group of disorders clinically characterized by the presence of cerebellar dysfunction. Initial assessment of patients with progressive cerebellar ataxia is complex because of an extensive list of potential diagnoses. A detailed history and comprehensive examination are required for an accurate diagnosis and hierarchical diagnostic investigations. Although no cure exists for most of these conditions, a small group of metabolic, hereditary, inflammatory, and immune-mediated etiologies of cerebellar ataxia are amenable to disease-modifying, targeted therapies. Over the past years, disease-specific treatments have emerged. Thus, clinicians must become familiar with these disorders because maximal therapeutic benefit is only possible when done early. In this article, we review disorders in which cerebellar ataxia is a prominent clinical feature requiring targeted treatments along with specific management recommendations.

Ondine's Curse: A Case of Anti-Hu Paraneoplastic Syndrome

A 60-year-old patient presented with neurological symptoms which proved to be a paraneoplastic syndrome secondary to a small-cell lung cancer. The investigations and treatment for these syndromes are discussed. The patient improved with high dose steroids and chemotherapy.

Inpatient rehabilitation performance of patients with paraneoplastic cerebellar degeneration

OBJECTIVE

To evaluate the functional improvement of rehabilitation inpatients with paraneoplastic cerebellar degeneration.

DESIGN

Retrospective review.

SETTING

Referral-based hospitals.

PARTICIPANTS

Cancer rehabilitation inpatients (N=7) admitted to 3 different cancer centers with a diagnosis of paraneoplastic cerebellar degeneration.

INTERVENTION

Medical records were retrospectively analyzed for demographic, laboratory, medical, and functional data.

MAIN OUTCOME MEASURE

FIM.

RESULTS

All 7 patients were white women (median age, 62y). Primary cancers included ovarian carcinoma (n=2), small cell lung cancer (n=2), uterine carcinoma (n=2), and invasive ductal breast carcinoma (n=1). Mean admission total FIM score was 61±23.97. Mean discharge total FIM score was 73.6±29.35. The mean change in total FIM score was 12.6 (P=.0018). The mean length of rehabilitation stay was 17.1 days. The mean total FIM efficiency was .73. Of the 7 patients, 5 (71%) were discharged home, 1 (14%) was discharged to a nursing home, and 1 (14%) was transferred to the primary acute care service.

CONCLUSIONS

To our knowledge, this is the first study to demonstrate the functional performance of a group of rehabilitation inpatients with paraneoplastic cerebellar degeneration. Despite the poor neurologic prognosis associated with this syndrome, these patients made significant functional improvements in inpatient rehabilitation. When appropriate, inpatient rehabilitation should be considered. Further studies with larger sample sizes are needed.

Paraneoplastic neurological syndromes

Paraneoplastic neurological syndromes are immune-mediated erroneous attacks on the central or peripheral nervous systems, or both, directed originally against the tumour itself. They have been known for more than 40 years, but recently the discovery of new subgroups of paraneoplastic encephalitis syndromes with a remarkably good response to immune therapy has ignited new clinical and scientific interest. Knowledge of these subgroups and their associated autoantibodies is important in therapeutic decision-making. However, the abundance of new autoantibodies and syndromes can be confusing. This review paper summarizes current knowledge and new developments in the field of paraneoplastic neurological syndromes, their classification, pathophysiology and treatment.

Gastric diffuse large B cell lymphoma presenting as paraneoplastic cerebellar degeneration: case report and review of literature

Paraneoplastic cerebellar degeneration (PCD) is a type of paraneoplastic neurological disorder (PND) that is associated with many solid tumors, Hodgkin's lymphoma (HL) and very rarely with non-Hodgkin's lymphoma (NHL). We report a case of PCD associated with gastric diffuse large B-cell lymphoma (DLBCL) in a patient who presented with acute onset of giddiness and double vision and had complete remission of the gastric lesion and marked improvement of cerebellar syndrome with rituximab-based combination chemotherapy. A brief review of the literature is also presented.