[Blood-brain barrier breakdown and autoimmune cerebellar ataxia]

Autoimmune cerebellar ataxia is a disease entity that affects the cerebellum and is induced by autoimmune mechanisms. The disease is classified into several etiologies, including gluten ataxia, anti-glutamate decarboxylase (GAD) ataxia, paraneoplastic cerebellar degeneration, primary autoimmune cerebellar ataxia and postinfectious cerebellar ataxia. The autoimmune response in the periphery cross-reacts with similar antigens in the cerebellum due to molecular mimicry. Breakdown of the blood‒brain barrier (BBB) could potentially explain the vulnerability of the cerebellum during the development of autoimmune cerebellar ataxia, as it gives rise to the entry of pathogenic autoantibodies or lymphocytes into the cerebellum. In this review, the maintenance of the BBB under normal conditions and the molecular basis of BBB disruption under pathological conditions are highlighted. Next, the pathomechanism of BBB breakdown in each subtype of autoimmune cerebellar ataxia is discussed. We recently identified glucose-regulated protein (GRP) 78 antibodies in paraneoplastic cerebellar degeneration and Lambert-Eaton myasthenic syndrome, and GRP78 antibodies induced by cross-reactivity with tumors can disrupt the BBB and penetrate anti-P/Q type voltage-gated calcium channel (VGCC) antibodies into the cerebellum, thus leading to cerebellar ataxia in this disease.

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.

FDG PET Unveils the Course of Paraneoplastic Cerebellar Degeneration: A Semiquantitative Analysis

ABSTRACT

In paraneoplastic cerebellar degeneration (PCD), the standard diagnostic workup might be inconclusive, especially in seronegative subtypes. Brain 18F-FDG PET is an accurate supportive diagnostic tool in immune-mediated disorders, but findings in PCD are controversial. Semiquantitative analysis of 18F-FDG PET can meaningfully assist visual assessment in different neurological conditions and has been mainly applied to disclose regional hypometabolism. We describe a seronegative PCD associated with small cell lung cancer in which 18F-FDG PET semiquantitative analysis accurately disclosed the longitudinal pathological changes of brain metabolism occurring in the acute and posttreatment remission stages and paralleling clinical impairment and response to treatment.

Transcriptomic immune profiling of ovarian cancers in paraneoplastic cerebellar degeneration associated with anti-Yo antibodies

BACKGROUND

Paraneoplastic neurological syndromes are rare conditions where an autoimmune reaction against the nervous system appears in patients suffering from a tumour, but not linked to the spreading of the tumour. A break in the immune tolerance is thought to be the trigger.

METHODS

The transcriptomic profile of 12 ovarian tumours (OT) from patients suffering from paraneoplastic cerebellar degeneration (PCD) linked to anti-Yo antibodies (anti-Yo PCD OT) was compared with 733 ovarian tumours (OT control) from different public databases using linear model analysis.

RESULTS

A prominent significant transcriptomic over-representation of CD8+ and Treg cells was found in anti-Yo PCD OT, as compared to the OT control. However, the overall degree of immune cell infiltration was similar, according to the ESTIMATE immune score. We also found an under-representation of M2 macrophages in anti-Yo PCD OT. Furthermore, the differentially expressed genes were enriched for AIRE-related genes, a well-known transcription factor associated with a broad range of autoimmune diseases. Finally, we found that the differentially expressed genes were correlated to the transcriptomic profiling of the cerebellar structures.

CONCLUSIONS

Our data pinpointed the enrichment of acquired immune response, particularly high density of CD8+ lymphocytes, and high-level expression of CDR-related antigens in anti-Yo PCD OT.

Paraneoplastic cerebellar degeneration associated with cerebellar hypermetabolism: Case report

RATIONALE

Paraneoplastic cerebellar degeneration (PCD) is an immune-mediated neurological deficit affecting the cerebellum. Anti-Yo antibody positive PCD is a rare occurrence most likely associated with gynecologic or breast malignancies. The identification of the underlying tumor is a diagnostic challenge in many of these patients.

PATIENT CONCERNS

We present a 68-year-old woman with acute symptoms of PCD as a first sign of underlying occult malignancy. Further investigation revealed a positive anti-Yo antibody. Although brain magnetic resonance imaging (MRI) was unremarkable, positron emission tomography (PET)/computed tomography (CT) revealed intense hypermetabolism of cerebellum and diffused hypometabolism in the rest of brain. On 1-year follow-up, despite the primary malignancy is still unknown, her symptoms improved significantly after immunotherapy.

DIAGNOSES

Paraneoplastic cerebellar degeneration.

INTERVENTIONS

The patient was given IV methylprednisolone 500 mg once a day for 5 consecutive days, followed by oral prednisone 60 mg once a day for 3 months.

OUTCOMES

The patient's symptoms were gradually improved during the hospitalization period. On one year follow up, she was able to walk independently and perform some simple tasks.

LESSONS

Cerebellar hypermetabolism in PCD suspected patients may help confirming the diagnosis in an earlier stage and may predict a better outcome after immunotherapy.

Paraneoplastic cerebellar ataxia associated with anti-Hu antibodies and benign ganglioneuroma

We describe a case of cerebellar ataxia associated with anti-Hu antibodies and benign ganglioneuroma. A 28-year-old woman developed progressive ataxia with hyporeflexia at the age of 19. Brain MRI showed progressive cerebellar atrophy. Neurophysiological studies, screening of immune-mediated ataxias, oncological markers, vitamin E and genetic tests for spinocerebellar ataxia types 1,2,3, Friedreich ataxia and POLG1 were negative. Anti-Hu antibodies were positive in Western blot and indirect immunofluorescence (1:640). Total-body computed tomography revealed a mediastinum mass; the histological diagnosis was maturing ganglioneuroma. Immunohistochemistry showed a mild reaction between the tumor and the patient's serum, and no reaction between the tumor and control serum. After surgery, serum anti-Hu titer decreased, while ataxic symptoms initially worsened and then stabilized. Ganglioneuroma is a benign tumor, usually derived from the maturation of a neuroblastoma. The benign histology and the presence of anti-Hu antibodies could be related to the positive oncological prognosis and to the slow clinical course mimicking a degenerative ataxia.

[Paraneoplastic cerebellar degeneration with bladder cancer confirmed the existence of an anti-neural antibody: a case report]

A 66-year-old man was diagnosed with bladder cancer at our urology department. Three months later, he developed subacute progressive cerebellar limb ataxia and truncal oscillation. Analysis of cerebrospinal fluid showed pleocytosis and increased concentrations of protein, while brain magnetic resonance imaging revealed no abnormalities. Based on the presence of the bladder cancer, the etiology of subacute cerebellar ataxia could be a paraneoplastic neurological syndrome. Four months later, the patient underwent transurethral resection of the bladder tumor, which was identified as urothelial cancer on the basis of pathological examinations. However, this procedure failed to improve his neurological symptoms. Serum paraneoplastic markers such as anti-Yo, anti-Hu, anti-Tr, and other antibodies were not detected. Immunohistochemical staining of mouse cerebellum using the patient's serum revealed coarse granular staining in the cytoplasm of Purkinje cells and diffuse staining in the neuropil of the molecular layer, suggesting the presence of an unknown antibody. Subsequently, one-dimensional electrophoresis western blotting using the patient's serum revealed several bands including a strong positive band of approximately 45 kDa in mouse cerebellum lysates but not in liver lysates. These bands have never been detected in sera derived from healthy donors. These results suggested the presence of a novel antibody in the patient's serum that might recognize the approximately 45 kDa protein related to paraneoplastic cerebellar degeneration. Cases of paraneoplastic neurological syndrome associated with bladder cancer have rarely been reported. We concluded that the present case may be categorized as paraneoplastic neurological syndrome caused by an unknown antibody.

Blood-brain barrier breakdown and cerebellar degeneration in the course of experimental neoplastic disease. Are circulating Cytokine-Induced Neutrophil Chemoattractant-1 (CINC-1) and -2alpha(CINC-2alpha) the involved mediators?

Cerebellar degeneration belongs to indirect effects of malignancy on the nervous system. Although the involvement of immune system is accepted as a hypothesis of its pathology, the clinical observations of ineffective immunomodulatory therapy suggest complex pathomechanisms, which await elucidation. The aim of this study was to prove the blood-brain barrier integrity, its relation to cerebellar degeneration and the role of circulating Cytokine-Induced Neutrophil Chemoattractant-1 (CINC-1) and Cytokine-Induced Neutrophil Chemoattractant-2alpha (CINC-alpha) in indirect effects of experimental malignancy. Two transplantable neoplasms: breast cancer (BC) and Morris hepatoma (MH) in rats were used in the study. The blood-brain barrier breakdown was clearly proved in the course of both malignancies. We observed also morphological signs of cerebellar degeneration in both models, with linear loss of Purkinje cells and homogenization changes more pronounced in breast cancer bearing rats. We have found a significant decrease of CINC-1 concentration in serum of rats with growing MH, however BC had no effect on CINC-1 concentration. Changes in serum CINC-2alpha concentrations in BC did not reach the level of significance, however in MH bearing rats the concentrations increased three weeks after tumour transplantation. In conclusion, we may state that the development of cerebellar degeneration as an indirect effect of experimental neoplasm can result from blood-brain barrier (BBB) breakdown and possible passage of neurotoxic factors. The decreased serum concentration of CINC-1 as neuroprotective agent and increased CINC-2alpha in late stage of MH may be considered for their contribution to cerebellar degeneration.

Paraneoplastic cerebellar degeneration in a patient with pseudomyxoma peritonei and breast cancer: case report and literature review

The case of a 31-year-old woman with progressive cerebellar degeneration preceding by several months the diagnosis and treatment of breast cancer initially and pseudomyxoma peritonei (PMP) with evidence of causative association with the latter is presented. Despite various chemotherapeutic and surgical manipulations, the patient did not substantially improve and succumbed 20 months following initial diagnosis of the neurological disorder. Interestingly, neurological symptoms partially regressed transiently only after surgical debulking of the PMP and not after the remission of breast cancer after various chemotherapeutic regimens suggesting an etiological relationship of the former and the cerebellar degeneration. Early recognition and appropriate therapy of this rare complication of PMP is imperative as it may be crucial for the outcome.

Morphological and immunohistochemical characterization of paraneoplastic cerebellar degeneration associated with Yo antibodies

INTRODUCTION

Immunohistochemical studies of paraneoplastic cerebellar degeneration (PCD) are rare, and the findings vary.

MATERIALS AND METHODS

We performed morphological and immunohistochemical characterization of the brain, medulla and tumour of two patients with PCD, Yo antibodies and ovarian adenocarcinoma.

RESULTS

The cerebellum of both patients had extensive loss of Purkinje cells. Microglia activation and T cells were found in the cerebellum, but B cells or deposits of IgG or complement were not detected. Microglia activation was also present in the brain stem and medulla. T cells were found in the ovarian adenocarcinoma.

CONCLUSION

PCD is characterized by loss of Purkinje cells and microglia activation, and the presence of T cells indicates cellular immune reactions in PCD and in ovarian cancer.

Anti-Yo-associated paraneoplastic cerebellar degeneration in a man with adenocarcinoma of the gastroesophageal junction

Anti-Yo-associated paraneoplastic cerebellar degeneration is a cancer-related syndrome affecting the nervous system. This syndrome occurs almost exclusively in middle-aged women with gynecological cancers and it is rarely found in patients with other types of cancer or in males. In this report we describe a male patient adenocarcinoma of the gastroesophageal junction and PCD with anti-Yo antibodies. To our knowledge, this is only the third report of PCD with positive anti-Yo antibodies in an esophageal tumor and the first report in a tumor of the gastroesophageal junction.

Ovarian cancer: PCD and brain metastases

Paraneoplastic cerebellar degeneration (PCD), the one of the most common paraneoplastic syndromes, refer to clinical disorders associated mostly with lung, ovarian and breast cancer, but not directly caused by the cancer or its metastases. Pathologic finding is an extensive loss of Purkinje cells in the cerebellum. Immunohistochemically, the auto-antibodies on the Purkinje cells had been detected. Clinically, PCD is characterized by sub-acutely evolving pancerebellar symptoms. Neurological dysfunction may appear before the detection of the underlying cancer. Therefore, the surgical exploration is necessary for the final diagnosis. The patient undergoes specific therapy. Soon, neurological status of the patient gets irreparable worse. Death come usually 2-3 years after the first symptoms of the PCD occurs. Case of a 63-years old woman with PCD as the first evidence of her cancer is reported. The patient developed brain metastases and died almost 3 years after the first symptoms of PCD occur

Progressive ataxic gait disorder

Paraneoplastic cerebellar degeneration (PCD) is a well-described paraneoplastic syndrome. In patients with anti-Yo associated PCD, neurological symptoms precede the diagnosis of the underlying cancer in approximately 60% of cases. Ovarian, breast and other gynaecological malignancies are most frequently found as causative malignancies. Antitumour treatment should be commenced at an early stage of the disease. Identification of the tumour is a diagnostic challenge in many of these patients. In the case reported herein, a secondary tumour with unknown primary was suggested after detection of a pathological lymph node in the right axilla by a positron emission tomography scan. Microscopic examination of the ultrasound-guided resected tissue was a poorly differentiated adenocarcinoma strongly positive for the C-ERB 2 oncoprotein. A micro-invasive mammary carcinoma was unable to be localized, even with the aid of magnetic resonance mammography and axillary clearance. Intravenous gamma-globulin and steroid treatment and rehabilitation failed to influence the neurological symptoms. The present patient also demonstrated diffuse increase on the T2 signal in the cerebellum, which may provide a useful diagnostic clue in the assessment of PCD.

[Multiple paraneoplastic syndromes occurring in the same patient: clinical, imaging and neuro-pathological documentation]

Paraneoplastic neurological syndromes (PNS) are remote effects of cancer, which are not caused by invasion of the tumour or its metastasis, but presumably immunologic mediated. They developed in less than 1% of patients with systemic cancers, most Limbic encephalitis (LE) is the most common clinical paraneoplastic syndrome attainting the CNS (Central Nervous System), and it is characterized by involvement of hippocampus and amygdala; LE is also the only one with clearly defined imaging features. We report a 64 year old man, former smoker, which presented multiple paraneoplastic syndromes, namely LE, opsoclonus-myoclonus, subacute cerebellar degeneration, brainstem encephalitis, sensory-motor neuropathy and inappropriate antidiuretic hormone secretion syndrome (SIADH); these syndromes were identifiable in the clinical and imaging examination, confirmed by the neuro-pathological study. Magnetic Resonance Imaging disclosed on T2 weighted images bilateral hyperintensity within medial temporal lobes, hypothalamus, thalamus, brain stem, upper and medium cerebellar peduncles and upper cervical spinal cord. The underlying tumour was not found in imaging studies or in the autopsy examination. A mediastinal adenopathy depicted a metastasis from low differentiated neoplasm cells, with some signs of neuroendocrine differentiation. With this case we provide a comprehensive illustration of the PNS, from a clinical, imaging and pathological point of view. This report also emphasises the importance of a diagnosis based on early clinical and imaging findings, given that, in most cases the cancer is not apparent.

Paraneoplastic cerebellar degeneration preceding the diagnosis of Hodgkin's lymphoma

Paraneoplastic cerebellar degeneration (PCD) can present as a severe and (sub)acute cerebellar syndrome. PCD can accompany different kinds of neoplasms including small cell lung cancer, adenocarcinoma of the breast and ovary, and Hodgkin's lymphoma. A 34-year-old patient is described with acute dysarthria, gait ataxia and diplopia. Despite extensive laboratory and radiological evaluations in this patient with rapidly deteriorating cerebellar syndrome, the diagnosis of a paraneoplastic syndrome was only made after several months, when an anti-Tr antibody was detected in his serum. The search for Hodgkin's disease as concomitant disorder was then started and resulted in stage II B disease. The patient was successively treated with six courses of etoposide, bleomycin, vinblastine and dexamethasone and radiotherapy, which resulted in a complete remission of the Hodgkin's disease. After starting therapy the cerebellar degeneration stabilised. The pathogenesis of neuronal damage in central nervous system paraneoplastic disorders such as the one we describe is not completely understood. Antitumour therapy is assumed to be the important cornerstone in stabilising the neurological condition. Improvement of the cerebellar syndrome in anti-Tr autoantibody paraneoplastic disease is a rare achievement. Early recognition of the concomitant disorders (anti-Tr autoantibody disease and Hodgkin's lymphoma) is of crucial importance.

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.

Autopsy findings in the nervous system and ovarian tumour of two patients with paraneoplastic cerebellar degeneration

OBJECTIVES

To review autopsy findings in paraneoplastic cerebellar degeneration.

MATERIALS AND METHODS

We report the autopsy results of two individuals with paraneoplastic cerebellar degeneration and ovarian cancer.

RESULTS

Both patients had extensive loss of cerebellar Purkinje cells and general activation of microglia in the central nervous system, as well as signs of immunactivation in the medulla.

CONCLUSION

The immunoactivation in PCD is widespread and involving more than the cerebellum.

Cerebellar hypermetabolism in paraneoplastic cerebellar degeneration

A 51 year old man with paraneoplastic cerebellar degeneration from gastric adenocarcinoma showed cerebellar hypermetabolism and increased perfusion on brain FDG-PET scan and SPECT during the acute stage of his illness. The patient underwent subtotal gastrectomy. The intensity of the hypermetabolism had decreased markedly on follow-up FDG-PET 3 months later following two cycles of chemotherapy. We suggest that the cerebellar hypermetabolism may have been due to an acute inflammatory process associated with an immunological reaction.

Clinical insights into paraneoplastic cerebellar degeneration

Neuroimaging is usually unremarkable in paraneoplastic cerebellar degeneration (PCD), at least in the early stages of the disease. A patient with proven PCD is reported in whom it could be shown that cerebellar atrophy evolved very rapidly and was present in early imaging studies. Even with the use of the whole spectrum of modern diagnostic tools, the underlying malignancy can be difficult to diagnose. In addition to mammography, MRI is recommended in these cases and repeat FDG-PET may be necessary.

Cachexia--induced cerebellar degeneration: involvement of serum TNF and MCP-1 in the course of experimental neoplastic disease

Cerebellar degeneration may be recognized as a remote effect of a growing tumor. We have analysed serum concentrations of tumor necrosis factor-alpha (TNF-alpha), macrophage chemoattractant protein-1 (MCP-1), thyroxine and insulin to elucidate the pathomechanism which may be of importance for the development of central degeneration in cachectic Morris hepatoma bearing rats. Serum TNF-alpha and MCP-1 levels were evaluated by means of the ELISA system, while thyroxine and insulin were estimated by radioimmunoassay. Microscopic examination using hematoxylin-eosin, Nissl and Klüver-Barrera staining revealed an atrophy in the cerebellum, homogenization changes of Purkinje cells and decreased cell density of the granular layer. In the Morris hepatoma bearing animals serum MCP-1 content was elevated while TNF-alpha, thyroxine and insulin concentrations were decreased. This study has demonstrated that circulating TNF-alpha and MCP-1, together with decreased levels of insulin and thyroxine accompany and may produce a milieu of factors involved in mechanisms of the development of cerebellar degeneration in cachectic hepatoma bearing rats.

Proteasome antibodies in paraneoplastic cerebellar degeneration

Antibodies to proteasome have been detected in several autoimmune diseases, including multiple sclerosis. We have investigated the presence of such antibodies in patients with paraneoplastic neurological syndromes, by Western blotting and immunohistochemistry. Antibodies to 20S proteasome were detected in the majority of patients with paraneoplastic cerebellar degeneration (PCD), but in only one of nine sera from patients with paraneoplastic encephalomyelitis/sensory neuronopathy (PEM/SN), and were not found in cancer patients in general. The results suggest that the immune responses in PCD differ from those of PEM/SN, whereas the functional significance of proteasome antibodies in PCD is yet to be determined.

[An autopsied case of paraneoplastic neurologic syndrome (limbic encephalitis, cerebellar degeneration, and pseudohypertrophy in the inferior olivary nuclei) associated with T cell lymphoma]

We describe a patient with paraneoplastic neurologic syndrome confirmed on postmortem examination. This 42-year-old man was admitted due to general fatigue, emaciation and acute-onset disorientation. Neurological examination revealed disorientation, moderate cognitive impairment, cerebellar ataxia, bilateral limitations and nystagmus in all directions during external ocular movement, swallowing disorder, bilateral Babinski sign, sensory disturbance in the distal parts of all extremities, and Romberg's sign. T-cell lymphoma was diagnosed following biopsy of the cervical lymph node. Neurological condition improved slightly after chemotherapy, but subsequently deteriorated. At about 6 years after the disease onset, brain magnetic resonance imaging (MRI) revealed atrophy of bilateral hippocampi and the upper vermis of the cerebellum. The patient died of pneumonia after a clinical course of about 6 years and 6 months. Pathologically, neuronal loss, reactive gliosis and perivascular lymphocytic infiltration were observed in the hippocampi, cerebellum, and inferior olivary nuclei. Lymphocytes around the vessels were positive for LCA and UCHL-1, but negative for CD8 and L26, and thus were considered to be T cells. No lymphoma cell was observed in the central nervous system or lymphatic organs. Based on the pathological findings, paraneoplastic neurologic syndrome (limbic encephalitis, cerebellar degeneration and olivary pseudohypertrophy) associated with T-cell type malignant lymphoma was diagnosed. Only three other cases of paraneoplastic neurologic syndrome associated with T-cell lymphoma have been reported. In those cases, death occurred due to the deterioration of malignant lymphoma, whereas the present patient died about 6 years after the remission of malignant lymphoma. Prognosis may thus depend on the course of the malignant lymphoma. In the present patient, neurological symptoms deteriorated after remission of malignant lymphoma, and no pathological lesion were found in the lymphatic organs. Lesions in the central nervous system in paraneoplastic neurological syndromes may follow a course independent of the original malignant disease.

Induction of humoral responses specific for paraneoplastic cerebellar degeneration-associated antigen by whole recombinant yeast immunization

Paraneoplastic cerebellar degeneration (PCD) is a potent autoimmune disorder in which antigen-driven responses toward the onconeural antigen are assumed to occur in patients. Yeast cell wall has adjuvant capacity and provides immunostimulatory effects of the antigen expressing in viable cells. The recombinant yeast expressing the PCD-associated antigen may become an immunogen for inducing PCD-associated autoimmunity in mice. We attempted to induce autoimmune responses with whole recombinant yeast expressing PCD-associated antigen. SJL/J strain of mouse is found to be a responder to the major epitope on the antigen for anti-Purkinje cell antibodies, and whole recombinant yeast could induce cellular and humoral autoimmune responses in vivo ion SJL/J mice. The immunization technique based on the recombinant yeast expressing a PCD-associated antigen provides a new tool for analyzing the underlying immunological pathomechanisms of PCD.

Strategies in detection of the primary tumour in anti-Yo associated paraneoplastic cerebellar degeneration

In patients with anti-Yo associated paraneoplastic cerebellar degeneration (PCD) neurological symptoms precede the diagnosis of the underlying cancer in about 60%. Ovarian carcinoma, breast cancer and other gynaecological malignancies are most frequently found as causative malignancies. Antitumour treatment should be applied in an early stage of disease. The identification of the tumour is a diagnostic challenge in many of these patients. In the first of two patients reported here a pelvic tumour was suggested after detection of a pathological lymph node and elevated tumour markers. The intraoperative findings appeared macroscopically normal during ovariectomy with adnexectomy. Not until microscopic examination of the resected tissue was performed was a tubal adenocarcinoma found. If intrapelvic gynaecological tumours are suspected a deliberate surgical exploration seems to be justified, but only after an intensive diagnostic investigation. To search for the underlying cancer in patients with paraneoplastic neurological disorders successive CT and [18F]-FDG-PET are widely recommended. Instead of this in the second reported patient whole-body dual-modality PET/CT was performed revealing enhanced uptake in three regions of the left thorax. By combining function and anatomy PET/CT was able to localise the lesions and characterise them as lymph node metastases of breast cancer. Diagnosis could be confirmed by subsequently executed needle biopsy. PET/CT seems to be highly applicable in the investigation of paraneoplastic disorders with unknown primary cancer. It may help in guidance of needle biopsy or to optimise the results of deliberate surgery and it provides whole-body tumour staging in a single session with higher diagnostic accuracy than PET alone.

An interferon-gamma ELISPOT and immunohistochemical investigation of cytotoxic T lymphocyte-mediated tumour immunity in patients with paraneoplastic cerebellar degeneration and anti-Yo antibodies

Eight patients with paraneoplastic cerebellar degeneration (PCD) and anti-Yo antibodies were investigated to determine whether there is any association between cytotoxic T lymphocyte (CTL) responses reactive with two previously defined Yo-derived, HLA-A2.1 restricted epitopes (cdr2-1 and cdr2-2) and the presence of tumour-infiltrating CD8+ CTLs. cdr2-1 and cdr2-2-specific CTL responses could not be detected in 5 HLA-A2.1(+) patients in an ex vivo interferon-gamma ELISPOT assay and only 2/9 tumour sections contained CD8(+) intratumoural lymphocytes suggesting a very limited role for CTL-mediated tumour immunity in this patient group, all of whom had evidence of widespread malignancy at the time of diagnosis and/or death.

Paraneoplastic cerebellar degeneration (PCD) associated with squamous cell carcinoma of the lung

We report a case of a 71-year-old man who presented with cerebellar dysfunction. He was diagnosed as having squamous cell carcinoma of the lung (T2N3M0, Stage IIIB). No anti-onconeural antibodies were found in his serum. Cerebral spinal fluid (CSF) examination showed mild mononuclear pleocytosis alone. Magnetic resonance imaging (MRI) of the brain and spinal cord revealed no abnormalities. At autopsy, there was complete disappearance of Purkinje cells with reactive astrocytosis. These findings are compatible with paraneoplastic cerebellar degeneration (PCD). To our knowledge, no case of PCD has been reported previously in patients with squamous cell carcinoma of the lung.

Paraneoplastic neurological syndrome: patient with anti-Yo antibody and breast cancer: a case report

Presented here is the case of a paraneoplastic cerebral degeneration (PCD) in a female patient with breast cancer and the indication of anti-Yo antibodies in the cerebrospinal fluid (CSF) and serum. The patient's primary indications were dizziness and a severe gait ataxia. The indication of anti-Yo antibodies led to the conclusion of the existence of a paraneoplastic cerebral degeneration. The antibodies in question are anti-Purkinje-cell autoantibodies acting against the antigens common to tumor and Purkinje cells which occur in association with a certain percentage of breast or ovarian cancers. The diagnosis of the primary tumor, that is clinically undetectable with conventional imaging processes, is performed with the aid of positron emission tomography (PET) to detect the presence of axillary lymph node metastases. The micro-invasive mammary carcinoma was able to be localized with the aid of MR mammography and, after MR mammography marking, was removed. The patient subsequently received adjuvant treatment with epirubicine and cyclophosphamide. This treatment failed to influence the paraneoplastic neurological symptoms.

Anti-Hu paraneoplastic syndrome presenting with brainstem-cerebellar symptoms and Lambert-Eaton myasthenic syndrome

Paraneoplastic syndrome (PNS) with two distinct neurological features was reported in a 50-year-old man who presented initially with vertigo, ataxia, dysarthria, tremor, confusion, urinary retention and hypotension. Pulmonary X-ray findings, class IIIb sputum cytology, and positive anti-Hu antibody established the diagnosis of PNS associated with small-cell lung cancer (SCLC). Two cycles of combined chemotherapy resulted in shrinkage of the lung tumor together with complete recovery of neurological symptoms and disappearance of anti-Hu antibody. Relapse of SCLC 4 months later with re-appearance of anti-Hu antibody required additional chemotherapy and irradiation. Eight months later, when multiple liver metastasis of SCLC was noticed, muscular weakness with positive waxing phenomenon compatible with Lambert-Eaton myasthenic syndrome (LEMS) developed. Postmortem examinations revealed residual SCLC in the primary lung, and massive liver metastasis with generalized lymph node involvement, but no tumors in the CNS. In the cerebellum, there was a slight loss of Purkinje cells with torpedo formation but without apparent lymphocytic infiltration. The present PNS was unique in that the relapse of SCLC was accompanied by the appearance of anti-Hu antibody, and that initial signs of brainstem-cerebellar symptoms, encephalopathy and autonomic failure were replaced by LEMS coinciding with the tumor recurrence.

Mechanisms underlying cerebellar motor deficits due to mGluR1-autoantibodies

Patients with Hodgkin's disease can develop paraneoplastic cerebellar ataxia because of the generation of autoantibodies against mGluR1 (mGluR1-Abs). Yet, the pathophysiological mechanisms underlying their motor coordination deficits remain to be elucidated. Here, we show that application of IgG purified from the patients' serum to cerebellar slices of mice acutely reduces the basal activity of Purkinje cells, whereas application to the flocculus of mice in vivo evokes acute disturbances in the performance of their compensatory eye movements. In addition, the mGluR1-Abs block induction of long-term depression in cultured mouse Purkinje cells, whereas the cerebellar motor learning behavior of the patients is affected in that they show impaired adaptation of their saccadic eye movements. Finally, postmortem analysis of the cerebellum of a paraneoplastic cerebellar ataxia patient showed that the number of Purkinje cells was significantly reduced by approximately two thirds compared with three controls. We conclude that autoantibodies against mGluR1 can cause cerebellar motor coordination deficits caused by a combination of rapid effects on both acute and plastic responses of Purkinje cells and chronic degenerative effects.

Reduction of P/Q-type calcium channels in the postmortem cerebellum of paraneoplastic cerebellar degeneration with Lambert-Eaton myasthenic syndrome

The aim of this study was to clarify whether autoimmunity against P/Q-type voltage-gated calcium channels (VGCCs) in the cerebellum was associated with the pathogenesis of paraneoplastic cerebellar degeneration (PCD) with Lambert-Eaton myasthenic syndrome (LEMS). We used human autopsy cerebellar tissues from three PCD-LEMS patients and six other disease patients including one with LEMS as the controls. We compared cerebellar P/Q-type VGCC in these patients and controls for the amount and ratio of autoantibody-channel complex using an 125I-omega-conotoxin MVIIC-binding assay with Scatchard analysis, and their distribution using autoradiography. The quantity of cerebellar P/Q-type VGCC measured by Scatchard analysis were reduced in PCD-LEMS patients (63.0 +/- 7.0 fmol/mg, n = 3), compared with the controls (297.8 +/- 38.9 fmol/mg, n = 6). The ratio of autoantibody-VGCC complexes to total P/Q-type VGCCs measured by immunoprecipitation assay were increased in PCD-LEMS patients. We analysed cerebellar specimens by autoradiography using (125)I-omega-conotoxin MVIIC, which specifically binds to P/Q-type VGCCs. In PCD-LEMS cerebellum, the toxin binding sites of P/Q-type VGCCs were markedly reduced compared with controls, especially in the molecular layer, which is the richest area of P/Q-type VGCCs in the normal cerebellum. This suggests that P/Q-type VGCCs of the cerebellar molecular layer is the immunological target in developing PCD-LEMS.

[Clinical presentation of immune mediated cerebellar ataxia]

Over the last decades, clinical evidence has accumulated indicating that the immune system may play an important role in some central nervous system diseases usually regarded as degenerative. The best known example is paraneoplastic cerebellar ataxia (PCA), which is thought to involve autoimmune cross-reaction between tumor and nervous system antigens. In the past twenty years, several antibodies directed against neuronal and tumor antigens have been described in association with PCA, leading to the description of different subtypes of PCA depending on the associated antibodies, the clinical course and the type of tumor. In some types, cerebellar ataxia occurs alone, whereas, in others, it is only one clinical feature in the setting of extensive nervous system disease. Circulating antibodies have also been described in patients with non-paraneoplastic cerebellar ataxia (N-PCA), suggesting that the immune system may be involved in certain cases of sporadic cerebellar ataxia. In this review, the clinical presentation of the different subtypes of potentially immune-mediated PCA and N-PCA will be described, and the experimental approaches developed in order to understand the pathogenic importance of the immune system in these ataxias will be discussed.

[Paraneoplastic cerebellar degeneration as initial presentation of a pancreatic small-cell carcinoma]

INTRODUCTION

Oat (small) cell carcinoma is the type of tumour most frequently associated to neurologic paraneoplastic syndromes. It is usually located in the lungs although it has been described in some other locations. Cerebellar symptoms may appear alone, associated to anti Yo antibodies ( Breast and gynaecologic carcinomas), or as manifestation of a more generalized paraneoplastic encephalopathy, associated to signs and symptoms of some other neurologic systems affected.

CASE REPORT

A 52 year old patient consulted due to a pancerebellar clinical picture, which started about two months before, and later associated to polineuropathy. Abdominal CT showed a 4 cm mass in the head of the pancreas. Pathologic evaluation demonstrated a poorly differentiated small cell pancreatic tumour. Anti Hu antibodies in high titres were found both in serum and cerebrospinal fluid.

DISCUSSION

The association of anti Hu immunity and paraneoplastic encephalomyelitis has been observed in patients with neuroblastoma, seminomas, colorectal, breast and prostate carcinomas and some types of sarcoma. Only about 1% of pancreatic malignancies correspond to small cell type. We have not found any previous report about the association between a paraneoplastic syndrome and pancreatic poorly differentiated small cell carcinoma.

[Paraneoplastic cerebellar degeneration associated with ovarian cancer: anti-Yo immunoreactivity in autoptic cerebellum and ovarian carcinoma]

Paraneoplastic cerebellar degeneration is a rare disorder caused likely by autoimmune mechanisms in malignant oncologic diseases, and the most common tumors are ovarian, breast, lung cancer, and m. Hodgkin. An immune reaction is supposed to be directed against identical antigens of cerebellum and tumor, and paraneoplastic antibodies called anti-Yo, anti-Hu, anti-Ri, or anti-Tr are often detected in blood and cerebrospinal fluid. The course of paraneoplastic cerebellar degeneration as a complication of ovarian cancer is described. The relationship between the malignancy and pathologic changes in cerebellum was confirmed by positive immunohistochemical and immunofluorescence reaction between a patient's anti-Yo-positive serum and her own Purkinje's and ovarian cancer cells.

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.

A case of paraneoplastic syndrome accompanied by two types of cancer

A case of paraneoplastic syndrome accompanied by two types of cancer is reported. The patient was a 62 year old man who progressively developed cerebellar ataxia, especially an abnormal gait. The anti-Hu antibody titre was high. A small tumour was detected in the middle lobe of the right lung and was surgically treated. The histology was adenocarcinoma. After lobectomy, however, the ataxia deteriorated, and plasma exchange, 250 ml/kg/day, was conducted for 6 days. After plasma exchange, the anti-Hu antibody titre decreased and the ataxia temporarily ceased to progress. A week after the last plasma exchange, a mass appeared in the anterior cervical region and rapidly increased in size. The biopsy of the neck tumour disclosed a small cell carcinoma. Five months later small cell carcinoma appeared in the left lung. This case shows the importance of searching for small cell carcinoma when anti-Hu antibodies are detected. It is assumed that plasma exchange removed not only a pathogenic factor of ataxia but also a factor which inhibited the growth of the small cell carcinoma. It is recommended that plasmapheresis should be performed with caution in paraneoplastic syndrome when the origin of a tumour is obscure.

Paraneoplastic cerebellar degeneration heralding fallopian tube adenocarcinoma

The objective of this paper is to describe an 81-year-old woman with subacute cerebellar degeneration due to fallopian tube adenocarcinoma. Serum anti-Yo antibodies were used to screen for pelvic malignancy. Their presence led to a meticulous search, which included bilateral salpingoophorectomy. Subsequently an occult fallopian tube adenocarcinoma was discovered. This case report highlights the diagnostic value of antineuroneal antibodies in females with subacute neurologic impairment in the form of paraneoplastic syndrome.

Anti-Yo antibodies and cerebellar degeneration in a man with adenocarcinoma of the esophagus

Serum antibodies to the Yo antigen are usually associated with paraneoplastic cerebellar degeneration arising in female patients with gynecological or breast malignancy and are rarely associated with other tumors. We report a male patient who presented with paraneoplastic cerebellar degeneration and anti-Yo antibodies following removal of an esophageal adenocarcinoma. This is only the third report of anti-Yo antibodies occurring in a male patient. The Yo antigen was expressed by the esophageal tumor but not in a frontal lobe cerebral metastasis identified at postmortem. Interestingly, CD8+ T-cell infiltration was also found in the tumor, but not in the metastasis, consistent with down-regulation of Yo expression by the tumor cells leading to evasion from immune-mediated tumor surveillance.

[Pathology of paraneoplastic syndromes of the central and peripheral nervous systems and muscle ]

INTRODUCTION AND DEVELOPMENT

The paraneoplastic neurological syndromes are alterations associated with neoplasias. However, they are not caused by metastases or complications such as infections, vascular disorders, metabolic or nutritional alterations or secondary effect of treatment. The paraneoplastic syndromes are often associated with the creation of autoantibodies against antigens produced by the neoplastia, but also may be against other cells or target molecules of the patient. Sometimes, especially with antibodies directed against cell membrane proteins, there is a close relationship between the antibody and the target organ, as for example antibodies against the acetylcholine receptor in myasthenia gravis. On other occasions, especially when the antigen is intracellular, the mechanism of the autoantibody reaction is not known. Finally, in a third group, the antibody associated with a particular paraneoplastic neurological alteration has not been identified. In this paper we describe the main paraneoplastic neurological pictures and known antibodies, including the molecular aspects and the neoplasias most frequently related to them.