Long term course of change in anti-Yo antibody content in paraneoplastic cerebellar degeneration

Anti-Yo antibody-mediated paraneoplastic cerebellar degeneration associated with cognitive affective syndrome in a patient with breast cancer: a case report and literature review

Breast cancer is the most common cancer in women, with 15%-25% of those tumours overexpressing the human epidermal growth factor receptor 2 (her2), which is associated with more aggressive disease. On rare occasions, patients present with a paraneoplastic syndrome months to years before their cancer diagnosis. Paraneoplastic cerebellar degeneration (pcd) is associated with fewer than 1% of cancers and is strongly associated with breast and gynecologic malignancies. Anti-Yo antibody is the antibody most frequently identified with the syndrome, and it is associated with a very poor prognosis. Recent studies have implicated a relationship between overexpression of her2 and anti-Yo-mediated pcd. Current pcd treatments include tumour removal, chemotherapy, targeted therapy, and immune-suppressive treatments. Outcomes of pcd are typically poor, and no guidelines for treatment currently exist. Early recognition followed by rapid initiation of treatment remains the cornerstone of therapy. Here, we present a case of anti-Yo-antibody pcd secondary to estrogen and progesterone receptor-negative, her2-positive breast cancer. Despite treatment with mastectomy, chemotherapy, and her2-targeted therapy, no significant neurologic improvement was achieved, and cerebellar cognitive affective syndrome subsequently developed.

Paraneoplastic cerebellar degeneration with anti-Yo antibodies - a review

The ataxic syndrome associated with Anti-Yo antibody, or Purkinje cell cytoplasmic antibody type 1 (PCA1), is the most common variant of paraneoplastic cerebellar degeneration (PCD). The typical presentation involves the subacute development of pancerebellar deficits with a clinical plateau within 6 months. The vast majority of cases have been reported in women with pelvic or breast tumors. Magnetic resonance imaging of the brain is often normal in the early stages, with cerebellar atrophy seen later. The underlying mechanism is believed to be an immunological reaction to cerebellar degeneration-related protein 2 (CDR2), a protein usually found in the cerebellum that is ectopically produced by tumor cells. Although both B- and T-cell abnormalities are seen, there is debate about the relative importance of the autoantibodies and cytotoxic T lymphocytes in the neuronal loss. Cerebrospinal fluid abnormalities, primarily elevated protein, lymphocytic pleocytosis, and oligoclonal bands, are common in the early stages. The low prevalence of this condition has not allowed for large-scale randomized controlled trials. Immunotherapies, such as steroids, intravenous immune globulins, and plasma exchange, have been extensively used in managing this condition, with limited success. Although some reports indicate benefit from antitumor therapies like surgery and chemotherapy, this has not been consistently observed. The prognosis for anti-Yo PCD is almost uniformly poor, with most patients left bedridden. Further studies are required to clarify the pathophysiology and provide evidence-based treatment options.

Demyelinating neuropathy with anti-CRMP5 antibodies predating diagnosis of breast carcinoma: favorable outcome after cancer therapy

INTRODUCTION

Breast cancer is exceptionally associated with anti-collapsin response mediator protein 5 (anti-CRMP5) antibody or demyelinating neuropathy. This paraneoplastic antibody is itself not associated with demyelinating neuropathy.

METHODS

Herein we describe a patient with a predominantly sensory ataxic demyelinating neuropathy associated with an IgG-kappa monoclonal gammopathy of uncertain significance (MGUS). Further investigations led to identification of anti-CRMP5 antibodies. An initial search for a malignancy proved negative. No immunomodulatory therapy was administered.

RESULTS

The patient developed breast carcinoma 2 years after the initial neurological symptoms, which was effectively treated by surgery, chemotherapy, hormone therapy, and radiotherapy. At neurological follow-up, 16 months after cancer treatment, she remained in remission and had made substantial neurological recovery. Electrophysiology showed significant amelioration, and serum anti-CRMP5 antibodies were undetectable. MGUS paraprotein level was unchanged.

CONCLUSION

This case widens the range of paraneoplastic manifestations of breast carcinoma to include anti-CRMP5 antibody-positive sensory ataxic demyelinating neuropathy, which, in this patient, improved after cancer treatment.

Immunological features of neurological paraneoplastic syndromes

Neurological paraneoplastic syndromes are a rare group of disorders that occur in 1-2% of people with malignancy. They are usually caused by an immune response, triggered by and directed against a tumour, that cross-reacts with protein expressed by the peripheral or central nervous system. Any part of the nervous system can be affected and patients often develop severe and permanent disability. Diagnosis can be difficult as in two-thirds of patients the neurological problems appear up to 5 years before the tumour manifests. However, certain of these syndromes are often associated with specific serum autoantibodies that can be useful both in diagnosis of the neurological syndrome and in focusing the search for a particular tumour. Thus, these antibodies can allow earlier identification and treatment of cancer and, potentially, a reduction in morbidity and mortality. It was only in the 1980s that the first anti-neuronal autoantibodies were characterized and their associations with clinical syndromes and tumours defined. Further antibodies have been isolated over the past 20 years and novel pathogenic mechanisms for several syndromes have been recognized. For example, voltage-gate ion channels seem to be a common target for autoantibodies involved in peripheral nerve diseases such as the Lambert-Eaton myasthenic syndrome and neuromyotonia (Isaacs' syndrome). However, the place of most paraneoplastic antibodies in the pathogenesis of central syndromes is yet to be fully elucidated.

Anti-Yo-associated paraneoplastic cerebellar degeneration in a man with gastric adenocarcinoma

Paraneoplastic cerebellar degeneration (PCD) with anti-Yo antibodies is almost always associated with ovarian and breast cancer. We describe a man with anti-Yo-positive PCD and gastric adenocarcinoma. The tumor cells were labeled with anti-Yo antibodies by immunohistochemistry. High serum titers of anti-Yo antibodies were found before surgery and decreased 6 months after resection of the tumor. The expression of Yo antigens by the tumor and the decrease in anti-Yo antibody titers after its removal suggest that the immune response against the Purkinje cells of the cerebellum was triggered by the tumor.

Failure to detect cytotoxic T cell activity against recombinant Yo protein using autologous dendritic cells as the target in a patient with paraneoplastic cerebellar degeneration and anti-Yo antibody

Paraneoplastic neurological syndromes are believed to be autoimmune neuronal degenerations that develop in some patients with systemic cancer. Although a high titer of anti-Yo antibody has been found in the sera and cerebrospinal fluid of patients with paraneoplastic cerebellar degeneration (PCD), the role of anti-Yo antibody in Purkinje cell loss has not been shown. Previously we found that all of nine Japanese patients with PCD who harbored anti-Yo antibody had HLA A24. In this present study we have examined cytotoxic T cell (CTL) activity against recombinant Yo protein in peripheral blood of a patient with PCD and anti-Yo antibody using autologous dendritic cells as the target. We did not detect CTL activity against Yo protein, though, this study does not exclude the possibility of the involvement of CTL in the development of PCD.