Early diagnosis and intravenous immune globulin therapy in paraneoplastic cerebellar degeneration

Immune-mediated Cerebellar Ataxias: Practical Guidelines and Therapeutic Challenges

Immune-mediated cerebellar ataxias (IMCAs), a clinical entity reported for the first time in the 1980s, include gluten ataxia (GA), paraneoplastic cerebellar degenerations (PCDs), antiglutamate decarboxylase 65 (GAD) antibody-associated cerebellar ataxia, post-infectious cerebellitis, and opsoclonus myoclonus syndrome (OMS). These IMCAs share common features with regard to therapeutic approaches. When certain factors trigger immune processes, elimination of the antigen( s) becomes a priority: e.g., gluten-free diet in GA and surgical excision of the primary tumor in PCDs. Furthermore, various immunotherapeutic modalities (e.g., steroids, immunoglobulins, plasmapheresis, immunosuppressants, rituximab) should be considered alone or in combination to prevent the progression of the IMCAs. There is no evidence of significant differences in terms of response and prognosis among the various types of immunotherapies. Treatment introduced at an early stage, when CAs or cerebellar atrophy is mild, is associated with better prognosis. Preservation of the "cerebellar reserve" is necessary for the improvement of CAs and resilience of the cerebellar networks. In this regard, we emphasize the therapeutic principle of "Time is Cerebellum" in IMCAs.

Treatment of Cerebellar Ataxia in the Context of Systemic Diseases

Purpose of review The purpose of this review is to assess the evidence behind treatment regimens for cerebellar ataxias occurring in the context of systemic disease. We will address systemic conditions which are associated with specific involvement of the cerebellum (rather than widespread nervous system involvement) and those conditions for which some degree of evidence of treatment response exists.

Recent findings We have divided systemic disorders affecting the cerebellum into systemic immunological disorders, endocrine and metabolic disorders and paraneoplastic. Recent studies have increased understanding of the range of cerebellar disorders associated with a systemic immunological condition. The identification of newer pathogenic antibodies has improved diagnosis in conditions which would have previously been labelled as idiopathic. However, their rarity and phenotypic variability makes defining optimal immunomodulatory treatment regimens challenging. There is some evidence for beneficial effects of immunomodulation, particularly in anti-GAD ataxia and Hashimoto’s encephalopathy, although, at this time, specific treatment regimens cannot be defined. Immune-mediated paraneoplastic cerebellar disorders show response to therapy dependent, to some extent, on the underlying pathogenic antibody. Much is still to be understood concerning treatment regimens for the ataxic manifestations of metabolic disorders, notably alcohol-induced cerebellar injury, which are common and which are associated with significant disability.

Summary Despite their rarity, cerebellar ataxias occurring in the context of systemic disease cause significant morbidity and better therapies are required to improve outcomes associated with these conditions.

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.

Treatment of paraneoplastic cerebellar degeneration

Paraneoplastic cerebellar degeneration is an uncommon autoimmune disorder characterized clinically by progressive, ultimately incapacitating ataxia and pathologically by destruction of cerebellar Purkinje cells, with variable loss of other cell populations. The disorder is most commonly associated with gynecological and breast carcinomas, small cell carcinoma of the lung, and Hodgkin’s disease and in most cases comes on prior to identification of the underlying neoplasm. The hallmark of paraneoplastic cerebellar degeneration is the presence of an immune response reactive with intracellular proteins of Purkinje or other neurons or, less commonly, against neuronal surface antigens. Evidence-based treatment strategies for paraneoplastic cerebellar degeneration do not exist; and approaches to therapy are thus speculative. Diagnosis and treatment of the underlying neoplasm is critical, and characterization of the antibody response involved may assist in tumor diagnosis. Most investigators have initiated treatment with corticosteroids, plasma exchange, or intravenous immunoglobulin G. Cyclophosphamide, tacrolimus, rituximab, or possibly mycophenolate mofetil may warrant consideration in patients who fail to stabilize or improve on less aggressive therapies. Plasma exchange has been of questionable benefit when used alone but should be considered at initiation of treatment to achieve rapid lowering of circulating paraneoplastic autoantibodies. Because the course of illness is one of relentless neuronal destruction, time is of the essence in initiating treatment. Likelihood of clinical improvement in patients with longstanding symptoms and extensive neuronal loss is poor.

[Synchronous appearance and improvement with anticancer chemotherapy of paraneoplastic cerebellar degeneration and Lambert-Eaton myasthenic syndrome complicated with small cell lung cancer]

A 62-year-old man who had suffered from instability of gait and double vision for two months was admitted to our hospital because of weakness of the extremities and ataxia of the extremities and trunk. Chest X-rays and CT scans showed enlargement of the left hilar lymph nodes and a nodular shadow in the left lung. Transbronchial biopsy revealed small cell lung cancer. We diagnosed the patient with two conditions: paraneoplastic cerebellar degeneration (PCD), based on cerebellar ataxia, the presence of Hu antineuronal antibodies, and the absence of cerebellar atrophy and malignancy; and Lambert-Eaton myasthenic syndrome (LEMS), based on weakness of the extremities, the presence of P/Q-type voltage-gated calcium channel antibodies, and waxing in the evoked electromyogram. Anticancer chemoradiation therapy that was started within three months of symptom onset resulted in reductions in size of the hilar lymph nodes and the nodule. Concurrently, cerebellar ataxia, weakness of the extremities, and double vision all disappeared. Anticancer chemotherapy is effective against LEMS while usually less effective against PCD. Early commencement of anticancer chemotherapy is recommended for the treatment of PCD with LEMS.

Paraneoplastic cerebellar degeneration associated with ovarian cancer

Paraneoplastic cerebellar degeneration (PCD) is a rare neurological disorder characterized by a widespread loss of Purkinje cells associated with a progressive pancerebellar dysfunction. PCD often precedes the cancer diagnosis by months to years. Here, we report the case of a 64-year-old woman who developed PCD symptoms, associated with high levels of anti-Yo antibodies, one year after a previous diagnosis of ovarian cancer. Clinical features, pathogenesis and treatment of PCD associated with cancer are discussed according to previous studies.

Anti-Yo positive paraneoplastic cerebellar degeneration: a report of three cases and review of the literature

Anti-Yo is an anti-Purkiney cell cytoplasmic antibody found in approximately 50% of patients with parancoplastic cerebellar degeneration (PCD). We report three patients with anti-Yo positive PCD (one ovarian carcinoma and two poorly differentiated adenocarcinomas consistent with breast origin). Two were treated with chemotherapy and plasmapheresis but died within months of the diagnosis from progressive neurological disease. The other was given gamma-globulin and has remained table at 6 months follow up. Anti-Yo antibodies are highly specific with almost all patients having breast or gynaecological malignanies. Commonly the tumour is of small volume and asymptomatic. Attempts at treatment are usually unsuccessful but there are a number of reports of stabilisation or improvement when treatment is begun before the development of severe neurological disability. The detection of anti-Yo antibodies is very useful for the diagnosis of PCD allowing early tumour detection and prompt institution of treatment.

The role of breast MRI in the investigation of anti-Yo positive paraneoplastic cerebellar degeneration

Paraneoplastic neurological syndromes are a group of rare and heterogeneous disorders complicating cancer through immune-mediated mechanisms. They typically arise before the diagnosis of malignancy, thus constituting its first clinical manifestation. A thorough search for the underlying tumour is necessary, as adequate tumour management is essential for both neurological prognosis and overall survival. The authors present the case of a 43 year-old woman who presented with a subacute cerebellar syndrome associated with the paraneoplastic anti-Yo antibody. Although paraneoplastic aetiology was immediately suspected, the diagnosis of the underlying tumour was not straightforward, as is often the case. This case report highlights the importance of directing tumour search for the most probable anatomic locations, according to patient demographics and risk factors as well as the type of onconeural antibodies present, and also the need to use the most sensitive diagnostic modalities appropriate for each target organ.

Progress in the management of paraneoplastic neurological disorders

Paraneoplastic neurological disorders (PNDs) are a rare and diverse group of neurological conditions that can involve any part of the nervous system. Diagnosis is facilitated by finding well-recognized autoantibodies directed against neural antigens in the sera and the cerebrospinal fluid. Identifying and eliminating the underlying malignancy is the mainstay of treatment. Immunomodulatory treatment is gaining more acceptance especially, where a malignancy could not be identified, oncology treatment is completed, or along with cancer treatment. Literature review shows only a handful of systematic prospective case series. Multicenter, prospective controlled clinical trials are needed for future therapeutic advances.

Neurologic improvement after high-dose intravenous immunoglobulin therapy in patients with paraneoplastic cerebellar degeneration associated with anti-Purkinje cell antibody

Paraneoplastic cerebellar degeneration (PCD) is a rare syndrome associated with systemic malignancies, most in lung and ovarian cancer. Cerebellar ataxia has previously been associated with the presence of anti-Purkinje cell antibodies (anti-Yo) in the serum and cerebrospinal fluid and responses to therapy are uncommon. We reported two patients were identified with delayed onset of PCD associated with high titer of CSF anti-Yo (1:30,000, 1:320 U/ml) and a marked elevation of tumor markers for ovarian cancer (CA-125 17,700 ng/ml, 43 ng/ml) titer 1 year and 6 months prior to discovery of the carcinoma. Both developed subacute onset of severe ataxia, dysarthria, tremor, nystagmus with progression to severe debilitation (wheelchair bound or bedridden status). One of these patients also developed dysphagia that required PEG tube feeding. They were treated with six cycles of intravenous immunoglobulin (IVIG) 0.4 gm/kg/day x 5 days, every 4-6 weeks in conjunction with combination chemotherapy of Taxol and Carboplatin after the surgical resection of ovarian cancer. In each case, a significant improvement of neurological deficits were seen after the third cycle of IVIG, approximately 4 months after initiation of treatment. This type of delayed response is contrary to the previous reports. Both patients could ambulate without assistance in correlation with dramatic decrease in anti-Yo titer (1:80, 1:320 U/ml) and CA-125 (11 ng/ml, 8 ng/ml). This is a first report of benefit from IVIG in patients with late onset of PCD, which showed a delayed response with significant neurological improvement.

Autoimmunity in paraneoplastic neurological syndromes

In patients with Paraneoplastic Neurological Disorders, the researcher detected several autoantibodies reacting with neuronal antigens and tumors; their characteristics supported the hypothesis that autoimmunity plays a part in these diseases and gave impetus to the study of these neurological disorders. The relationship between detection of anti-neuronal antibodies, clinical syndromes, and certain types of tumors suggested the utility of these antibodies as a new tool for clinical diagnosis, although their function in the pathogenesis of the various syndromes is still unclear. This paper intends to review the characteristics of the anti-neuronal antibodies so far identified, their correlation with clinical syndromes, and the function of antigens. In addition, the paper will offer some insights on the immunological mechanisms of neuronal damage and on treatment options.

Insulin-like growth factor I treatment for cerebellar ataxia: Addressing a common pathway in the pathological cascade?

In the present work we review evidence supporting the use of insulin-like growth factor I (IGF-I) for treatment of cerebellar ataxia, a heterogeneous group of neurodegenerative diseases of low incidence but high societal impact. Most types of ataxia display not only motor discoordination, but also additional neurological problems including peripheral nerve dysfunctions. Therefore, a feasible therapy should combine different strategies aimed to correct the various disturbances specific for each type of ataxia. For cerebellar deficits, and most probably also for other types of brain deficits, the use of a wide-spectrum neuroprotective factor such as IGF-I may prove beneficial. Intriguingly, both ataxic animals as well as human patients show altered serum IGF-I levels. While the pathogenic significance of IGF-I, if any, in this varied group of diseases is difficult to envisage, disrupted IGF-I neuroprotective signaling may constitute a common stage in the pathological cascade associated to neuronal death. Indeed, treatment with IGF-I has proven effective in animal models of ataxia. Based on this pre-clinical evidence we propose that IGF-I should be tested in clinical trials of cerebellar ataxia in those cases where either serum IGF-I deficiency (as in primary cerebellar atrophy) or loss of sensitivity to IGF-I (as in ataxia telangiectasia) has been reported. Taking advantage of the widely protective and anabolic actions of IGF-I on peripheral tissues, this neurotrophic factor may provide additional therapeutic advantages for many of the disturbances commonly associated to ataxia such as cardiopathy, muscle wasting, or immune dysfunction.

Immunomodulatory treatment trial for paraneoplastic neurological disorders

Paraneoplastic neurological disorders are devastating remote effects of malignancy. Despite compelling evidence of an autoimmune pathogenesis, empiric immunomodulatory treatment of these disorders is often ineffective. However, very few systematic studies have been conducted, and the treatment of patients without active malignancy has not been addressed. We conducted a prospective open-label treatment study of plasma exchange plus conventional cancer chemotherapy (10 patients) or plasma exchange plus continuous oral cyclophosphamide (10 patients). All patients had progressive symptoms and at least moderate disability at enrollment (mean Rankin score, 3.4). Patients who had experienced symptoms for more than 12 months were excluded (mean duration of symptoms at enrollment, 3.6 months). The primary outcome measure was change in quantitative disability measures (Rankin and Barthel scores) after 6 months of treatment; a positive response was defined as stability or improvement in disability. Overall, 50% of patients had a positive response at 6 months (6 patients had improved by at least 1 Rankin grade). Patients with good outcome tended to be those with less disability at time of enrollment. Hematologic toxicity was common among those receiving cyclophosphamide. Aggressive immunosuppression early in the clinical course should be considered in patients who have paraneoplastic neurological disorders, even when there is no evidence of active malignancy.

Anti-Yo antibody-positive cerebellar degeneration associated with endometrial carcinoma: case report and review of the literature

Paraneoplastic cerebellar degeneration (PCD) is a rare, severely debilitating disease, often with a rapid onset and progression, which predate the diagnosis of malignancy. Despite characteristic features, diagnosis is commonly difficult and successful therapy, which relies on early instigation of treatment, is rare. Here we present a patient in whom anti-Yo antibody-positive PCD was associated with endometrial carcinoma and an extensive review of the literature outlining the clinical features, pathogenesis and treatment of PCD.

Intravenous immunoglobulin in neurological disease: a specialist review

Treatment of neurological disorders with intravenous immunoglobulin (IVIg) is an increasing feature of our practice for an expanding range of indications. For some there is evidence of benefit from randomised controlled trials, whereas for others evidence is anecdotal. The relative rarity of some of the disorders means that good randomised control trials will be difficult to deliver. Meanwhile, the treatment is costly and pressure to "do something" in often distressing disorders considerable. This review follows a 1 day meeting of the authors in November 2000 and examines current evidence for the use of IVIg in neurological conditions and comments on mechanisms of action, delivery, safety and tolerability, and health economic issues. Evidence of efficacy has been classified into levels for healthcare interventions (tables 1 and 2).

[Paraneoplastic subacute cerebellar degeneration: case report]

We report a 40-year-old woman with subacute cerebellar degeneration associated with ovarian cancer. We briefly review the clinical and laboratory features of this syndrome, and emphasize the importance of its prompt recognition, which many times makes possible the early detection and treatment of the primary disorder.

Treatment of paraneoplastic neurological syndromes with antineuronal antibodies (Anti-Hu, anti-Yo) with a combination of immunoglobulins, cyclophosphamide, and methylprednisolone

OBJECTIVES

To evaluate the effect of a combination of immunoglobulins (IVIg), cyclophosphamide (CTX), and methylprednisolone (MP) on the clinical course of patients with paraneoplastic neurological syndrome (PNS) and antineuronal antibodies (Abs).

METHODS

Seventeen patients with paraneoplastic encephalomyelitis/sensory neuropathy (PEM/SN) with anti-Hu Abs (n = 10) or cerebellar degeneration (PCD) with anti-Yo Abs (n = 7) received one to nine cycles (mean 3.5) of a combination of IVIg (0.5 g/kg/day from days 1 to 5), CTX (600 mg/m2 at day 1) and MP (1g/day from day 1 to 3). The Rankin scale (RS) was used to evaluate the response. A positive response was considered as either improvement or stabilisation in patients who were still ambulatory (RS< or =3) at the onset of treatment, whereas only improvement, and not stabilisation, was considered a therapeutic benefit in bedridden patients (RS> or =4).

RESULTS

Tolerance was good and no patient experienced grade 3/4 toxicity (World Health Organisation). Sixteen patients were evaluable for response. Of the seven patients with RS> or =4, none improved. Of the nine patients with RS< or =3, none improved but three (two SN and one PCD) stabilised for 4, 35, and 16 months.

CONCLUSIONS

This study suggests that vigorous immunosuppressive treatment is not useful in severely disabled PNS patients with antineuronal Abs. In a minority of patients (mainly with SN) who are not severely disabled at the onset of treatment, a transient stabilisation is possible and deserves further evaluation.

Intravenous immunoglobulin in the treatment of autoimmune neuromuscular diseases: present status and practical therapeutic guidelines

This review summarizes the current status of intravenous immunoglobulin (IVIg) in the treatment of autoimmune neuromuscular disorders and the possible mechanisms of action of the drug based on work in vivo, in vitro, and in animal models. Supply of idiotypic antibodies, suppression of antibody production, or acceleration of catabolism of immunoglobulin G (IgG) are relevant in explaining the efficacy of IVIg in myasthenia gravis (MG), Lambert-Eaton myasthenic syndrome (LEMS), and antibody-mediated neuropathies. Suppression of pathogenic cytokines has putative relevance in inflammatory myopathies and demyelinating neuropathies. Inhibition of complement binding and prevention of membranolytic attack complex (MAC) formation are relevant in dermatomyositis (DM), Guillain-Barré syndrome (GBS), and MG. Modulation of Fc receptors or T-cell function is relevant in chronic inflammatory demyelinating polyneuropathy (CIDP), GBS, and inflammatory myopathies. The clinical efficacy of IVIg, based on controlled clinical trials conducted in patients with GBS, CIDP, multifocal motor neuropathy (MMN), DM, MG, LEMS, paraproteinemic IgM anti-myelin-associated glycoprotein (anti-MAG) demyelinating polyneuropathies, and inclusion body myositis is summarized and practical issues related to each disorder are addressed. The present role of IVIg therapy in other disorders based on small controlled or uncontrolled trials is also summarized. Finally, safety issues, risk factors, adverse reactions, spurious results or serological tests, and practical guidelines associated with the administration of IVIg in the treatment of neuromuscular disorders are presented.

Paraneoplastic Diseases of the Nervous System

Several neurologic paraneoplastic disorders are believed to be caused by an autoimmune reaction against an antigen or antigens coexpressed by tumor cells and neurons. Of the paraneoplastic syndromes, the Lambert-Eaton myasthenic syndrome (LEMS)--in which autoantibodies downregulate voltage-gated calcium channels at the presynaptic nerve terminal--is associated with the strongest evidence of an autoimmune cause. For the other syndromes, including cerebellar degeneration, multifocal encephalomyelitis, sensory neuronopathy, limbic encephalitis, opsoclonus-myoclonus, and retinal degeneration, an autoimmune cause is indicated by the presence of specific anti-neuronal antibodies. These antibodies serve as a useful diagnostic tool, but their actual role in causing neuronal injury and clinical disease remains unclear. A small percentage of patients with paraneoplastic disorders shows major neurologic improvement after successful treatment of the associated tumor. Of patients who require further therapy for the neurologic disorder, those with LEMS have the best outcome. The response to immunosuppression among patients with paraneoplastic central nervous system (CNS) dysfunction is much less favorable. Although exceptions clearly exist, most patients with CNS paraneoplastic disorders do not improve despite tumor treatment and immunosuppressive therapy. It is likely that many patients already have irreversible neuronal injury at the time of diagnosis. The decision to attempt immunosuppressive treatment must be made on an individual basis.

Anti-Yo positive paraneoplastic cerebellar degeneration associated with ovarian carcinoma: case report and review of the literature

Paraneoplastic cerebellar degeneration (PCD) is a rare nonmetastatic neurological complication in cancer patients. Anti-Yo is one of the anti-onconeural antibodies found in PCD patients. It is believed that anti-Yo occurs almost always in women and is most likely associated with gynecologic or breast cancers, although exceptions exist. Here we report a PCD patient with ovarian cancer having high-titer anti-Yo. The acute onset of her PCD symptoms mimicked that of a stroke. Her ovarian cancer tissue contained abundant plasma cells and lymphocytes. After a thorough review of the literature, we propose a schematic hypothesis for the autoimmune pathogenesis of PCD. Despite anecdotal case reports of neurological improvement with different combinations of treatment, including IVIg, there is still no definitely effective treatment for PCD. Further research on the pathogenesis of PCD may lead to more effective therapies.

A review of the therapy of paraneoplastic neurologic syndromes

The therapy of paraneoplastic neurologic syndromes remains unclear and warrants a systematic review of the literature. Reports in English and foreign language literature were abstracted. Data were sorted by the primary paraneoplastic neurologic syndrome, the primary malignancy, and the methods of treatment. Neurologic improvement follows surgical, chemotherapeutic, and radiation treatments. Adjuvant immunosuppressive therapy with steroids, plasmapheresis, or immunoglobulin may help stabilize the progression of neurologic symptoms. Syndromes characterized by inflammation or neurotransmitter production without neuronal loss are most responsive to therapy. While treatment of the underlying cancer with appropriate surgery, chemotherapy, and radiation is recommended, the paraneoplastic syndrome should probably be managed with immunosuppressive therapy.

Intravenous immunoglobulin treatment of neurological autoimmune diseases

Intravenous immunoglobulin (IVIg) has been widely used in neurological diseases during the last decade. The current indications of IVIg in neurological diseases are reviewed and discussed on the basis of the available experimental data and clinical trials. Compared to other immunomodulating treatments used in neurological diseases, IVIg has only few side effects with a small risk of transmission of infectious agents. Good clinical evidence for the effectiveness is available for Guillain-Barré-Syndrome, chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy. In conditions like myasthenia gravis and myositis favourable effects of IVIg were reported, but future studies have to be awaited. For all other neurological conditions where IVIg has been administered, there is currently no support for the use of IVIg other than in controlled trials. In conclusion, IVIg is a promising immunomodulary therapy that has been shown to be effective in some neurological autoimmune diseases. Routine use in neurological practice should be restricted to diseases for which a positive effect has been proven in controlled trials. For all other conditions no definite recommendations can presently be made.

Intravenous immunoglobulin treatment in paraneoplastic neurological syndromes with antineuronal autoantibodies

OBJECTIVE

To evaluate the effect of intravenous high dose human immunoglobulin (IVIg) therapy on the clinical course and autoantibody titres of patients with neurological paraneoplastic syndromes.

METHODS

Twenty two patients with paraneoplastic encephalomyelitis and sensory neuronopathy syndrome associated with anti-Hu antibodies (18) or paraneoplastic cerebellar degeneration (PCD) with anti-Yo antibodies (four), were treated with 1-26 (mean 5.8) cycles of IVIg. The Rankin scale was used to evaluate the response.

RESULTS

The only serious toxicity was one case of haemolytic anaemia. Twenty one patients were evaluable for therapeutic response. One patient, with subacute sensory neuronopathy (SSN), improved for at least 15 months, 10 remained stable (eight with anti-Hu and two with anti-Yo antibodies), and 10 deteriorated (eight with anti-Hu and two with anti-Yo antibodies). In seven of the 10 patients who stabilised, the syndrome had already made a plateau when the treatment was started but three patients (one with anti-Hu and two with anti-Yo antibodies) who had still been progressing stabilised for six, eight, and more than 48 months, including one patient with SSN who achieved stabilisation when the neurological dysfunction was only moderate (Rankin scale = 3). Another patient with SSN and initial stable response worsened when IVIg was reduced and improved when it was increased. No significant predictive factors of outcome could be identified but improvement or stabilisation was more frequent in patients with isolated involvement of the peripheral nervous system (62%) than in patients with evidence of CNS damage (37%) at the onset of treatment. Stabilisation in patients with CNS involvement was only achieved when the neurological dysfunction was already severe (Rankin scale > 3). The titres of autoantibodies did not change significantly.

CONCLUSION

Treatment with IVIg at the doses given in the present protocol was not effective in paraneoplastic CNS syndromes associated with antineuronal antibodies. The role of this regime in the treatment of SSN should be further evaluated.

Autoimmune central nervous system paraneoplastic disorders: mechanisms, diagnosis, and therapeutic options

The presence of specific antineuronal antibodies in some patients with paraneoplastic central nervous system (CNS) disorders supports the theory that these syndromes have an autoimmune etiology. The anti-Purkinje cell antibodies (APCAs) in some patients with paraneoplastic cerebellar degeneration and ovarian or breast carcinomas stain the cytoplasm of Purkinje cells. APCAs react with several distinct neuronal protein autoantigens, including proteins featuring a "leucine zipper" sequence motif, which suggests that they function in regulating DNA transcription. Type 1 anti-neuronal nuclear antibodies (ANNA-1) associated with paraneoplastic encephalomyelitis and small-cell lung carcinoma stain the nucleus and cytoplasm of all neurons, and react with a group of 35- to 40-kd proteins in neuronal immunoblots. The protein targets of ANNA-1 belong to a family of RNA-binding proteins that probably regulate posttranscriptional processing of RNA. Type 2 anti-neuronal nuclear antibodies (ANNA-2) associated with paraneoplastic opsoclonus-ataxia and breast carcinoma also produce a panneuronal immunocytochemical staining pattern, but react with a group of higher-molecular-mass proteins (53-61 kd and 79-84 kd); these autoantigens probably also function as RNA-binding proteins. Several patients with paraneoplastic stiff-man syndrome have antibodies against a 128-kd synaptic protein. These antineuronal antibodies are highly specific (but not infallible) diagnostic markers for the presence of a neoplasm in patients who present with neurological dysfunction. The actual role of these autoantibodies in the pathogenesis of neuronal damage and clinical disease remains to be determined. Current management options for patients with CNS neurological paraneoplastic syndromes are very limited. Only a small minority of patients with paraneoplastic cerebellar degeneration or encephalomyelitis show significant neurological improvement after successful tumor treatment and/or immunosuppressive treatments, while patients with paraneoplastic opsoclonus or stiff-man syndrome have a somewhat better outlook.

Therapy for paraneoplastic neurologic syndromes in six patients with protein A column immunoadsorption

BACKGROUND

Paraneoplastic neurologic syndromes, although rare, cause significant morbidity and mortality. They are thought to be immunologically mediated, but to date those involving the central nervous system (CNS) have not been particularly responsive to immunologic therapy. The use of the novel immunomodulator, protein A immunoadsorption, was explored to address this question.

METHODS

Six patients with neurologic paraneoplastic syndromes were treated with this technique, using the "off line" method. Two hundred fifty ml of plasma was perfused through a column containing protein A covalently attached to a silica matrix. The plasma was then returned to the patient.

RESULTS

Five of the patients responded to the therapy, with complete and durable responses in three patients with opsoclonus-myoclonus, objective, though transient, improvement in one patient with paraneoplastic brainstem encephalitis associated with a Merkel cell tumor, and stabilization and partial improvement in one patient with paraneoplastic limbic encephalitis. The patient without response developed a cutaneous vasculitis after the second treatment, and therapy was discontinued.

CONCLUSIONS

This therapy appears beneficial for a number of paraneoplastic syndromes, most dramatically in the opsoclonus/myoclonus syndrome.

Anti-tumour therapy in paraneoplastic neurological disease

Paraneoplastic neurological syndromes have attracted attention in recent years. Detection of auto-antibodies directed against CNS and PNS structures have suggested an autoimmune etiology. This review is based on reports from the past 10 years and summarizes the therapeutic results in 258 patients suffering from paraneoplastic neurological disease including paraneoplastic encephalomyelitis, sensory neuronopathy, cerebellar degeneration, motor neurone disease and stiff man syndrome. The results show that in some entities such as Lambert-Eaton syndrome successful treatment can be expected. In other syndromes such as subacute sensory neuronopathy or paraneoplastic cerebellar degeneration therapeutic success varies from 5 to 10%.

Passage of intravenous immunoglobulin and interaction with the CNS

Images