Paraneoplastic Cerebellar Degeneration: The Importance of Including CDR2L as a Diagnostic Marker.

OBJECTIVE: Investigate the value of including cerebellar degeneration-related protein 2-like (CDR2L) as a marker in commercial diagnostic tests for anti-Yo-associated paraneoplastic cerebellar degeneration (PCD). METHODS: We included sera and CSF samples from 24 patients with suspected PCD (6 of whom had PCD with underlying gynecologic or breast cancer), who were positive for Yo antibodies using the commercially available, paraneoplastic neurologic syndromes (PNS) 14 Line Assay from Ravo Diagnostika. The samples were further evaluated using the EUROLINE PNS 12 Ag Line Assay and a cell-based assay (CBA) from Euroimmun. For confirmation of positive lineblot results, we used indirect immunofluorescence of rat cerebellar sections. We also tested all samples in 2 assays developed in-house: a CBA for CDR2L and a Western blot analysis using recombinant cerebellar degeneration-related protein 2 (CDR2) and CDR2L proteins. RESULTS: In PNS 14 and PNS 12 Ag Line Assays, anti-CDR2 reactivity was observed for 24 (100%) and 20 (83%) of the 24 samples, respectively. Thirteen of 24 subjects (54%) were also positive using the Euroimmun CBA. Rat cerebellar immunofluorescence was the best confirmatory test. In our in-house CBA for CDR2L and Western blot for CDR2 and CDR2L, only the 6 patients with confirmed PCD reacted with CDR2L. CONCLUSIONS: Commercially available tests for Yo antibody detection have low specificity for PCD because these assays use CDR2 as antigen. By adding a test for CDR2L, which is the major Yo antigen, the accuracy of PCD diagnosis greatly improved. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that a CBA for CDR2L accurately identifies patients with PCD.

Paraneoplastic cerebellar degeneration and lambert-eaton myasthenia in a patient with merkel cell carcinoma and voltage-gated calcium channel antibodies.

INTRODUCTION: Merkel cell carcinoma is a rare cutaneous, aggressive tumor. Although it shares many neuroendocrine features with small cell lung carcinoma, it has only occasionally been reported with paraneoplastic neurological syndromes. METHODS: A healthy 67-year-old man developed acute ataxia, vertigo, and nausea. Subsequently he also developed dysarthria, diplopia, xerostomia, fatigability and progressive anorexia. He underwent a full diagnostic workup and was found to have a high titer of voltage-gated calcium channel antibodies in serum and cerebrospinal fluid, neurophysiological findings compatible with Lambert-Eaton myasthenia and neurological signs compatible with cerebellar degeneration. RESULTS: A positron emission tomography study revealed a hypermetabolic lesion in the axilla, subsequently biopsied and consistent with Merkel cell carcinoma. CONCLUSIONS: In most previous reports, neurological symptoms preceded the Merkel cell carcinoma diagnosis, and the primary localization was in lymph nodes. This tumor should be considered in patients with paraneoplastic syndrome, and particularly Lambert-Eaton myasthenia after exclusion of small cell lung carcinoma. Muscle Nerve 56: 998-1000, 2017.

Seronegative paraneoplastic cerebellar degeneration: the PNS Euronetwork experience.

BACKGROUND AND PURPOSE: To describe the characteristics of patients presenting a paraneoplastic cerebellar degeneration without classical onconeural antibodies (seronegative PCD). METHODS: Thirty-nine seronegative PCD patients from the Paraneoplastic Neurological Syndrome Euronetwork were retrospectively analyzed and compared with 180 patients with PCD associated with classical onconeural antibodies (seropositive PCD). RESULTS: No patient had anti-CASPR2 or anti-mGluR1 antibodies. No significant difference between the clinical characteristics of seronegative and seropositive PCD patients was observed. Yet the frequency of associated tumors was different. Lymphoma was more frequent in seronegative than in seropositive women (24% vs. 2%, P = 0.002) whilst gynecological cancer were less frequent (38% vs. 74%, P = 0.002). In comparison with seropositive men, seronegative men more frequently had a non-small-cell lung cancer (27% vs. 6%, P = 0.08) or a genitourinary cancer (22% vs. 0%, P = 0.04) but less frequently a small-cell lung cancer (23% vs. 74%, P = 0.002). Seronegative and seropositive PCD patients with similar tumors had a similar overall survival. CONCLUSION: The clinical characteristics of seronegative and seropositive PCD are similar but the spectrum of associated tumors is different. The immunological scenario of seronegative PCD seems to be different from that of limbic encephalitis with only few patients harboring anti-neuropile antibodies.

Paraneoplastic cerebellar degeneration caused by ovarian clear-cell carcinoma.

Paraneoplastic cerebellar degeneration is a paraneoplastic neurological syndrome caused by the remote effect of certain systemic cancers and is characterized by subacute cerebellar symptoms. A 62-year-old woman suffering from unidentified cerebellar symptoms was admitted to our hospital. Paraneoplastic cerebellar degeneration was suspected and ovarian cancer was detected after the systemic examination for malignancy. The symptoms of vertigo and dysarthria were improved a little after surgical operation and treatments of γ-globulin, steroid pulse and tacrolimus hydrate. The cerebellar symptoms of paraneoplastic cerebellar degeneration are often evident prior to detection of malignancy. It is important to perform systemic examination for malignancy in case of unidentified cerebellar symptoms.

Paraneoplastic cerebellar degeneration with anti-Yo antibodies associated with metastatic uveal melanoma.

Paraneoplastic cerebellar degeneration (PCD) is characterized by subacute development of pancerebellar dysfunction as a remote effect of a systemic cancer and usually develops in patients affected by gynecological tumors. Uveal melanoma is a very rare disease with a severe prognosis. A 58-year-old man affected by uveal melanoma developed anti-Yo positive paraneoplastic cerebellar degeneration (PCD) 42 months after the initial diagnosis. The onset and worsening of the neurological symptoms were parallel to the course of liver metastasis. To our knowledge this is the first case of PCD in a patient with uveal melanoma. We speculate that the cerebellar degeneration-related protein 2 (CDR2), to which the anti-Yo antibodies are directed, may have been expressed in melanoma cells and conferred proliferative advantage to the disease.

Paraneoplastic cerebellar degeneration associated with an onconeural antibody against creatine kinase, brain-type.

Onconeural immunity, a cancer-stimulated immune reaction that cross-reacts with neural tissues, is considered to be the principal pathological mechanism for paraneoplastic neurological syndromes (PNS). A common PNS is paraneoplastic cerebellar degeneration (PCD). We had encountered a PCD patient with urothelial carcinomas (UC) of the urinary bladder who was negative for the well-characterized PNS-related onconeural antibodies. In the present study, we aimed to identify a new PCD-related onconeural antibody, capable of recognizing both cerebellar neurons and cancer tissues from the patient, and applied a proteomic approach using mass spectrometry. We identified anti-creatine kinase, brain-type (CKB) antibody as a new autoantibody in the serum and cerebrospinal fluid from the patient. Immunohistochemistry indicated that anti-CKB antibody reacted with both cerebellar neurons and UC of the urinary bladder tissues. However, anti-CKB antibody was not detected in sera from over 30 donors, including bladder cancer patients without PCD, indicating that anti-CKB antibody is required for onset of PCD. We also detected anti-CKB antibody in sera from three other PCD patients. Our study demonstrated that anti-CKB antibody may be added to the list of PCD-related autoantibodies and may be useful for diagnosis of PCD.

Protein kinase Cγ antibodies and paraneoplastic cerebellar degeneration.

Onconeural antibodies are diagnostic markers for paraneoplastic neurological syndromes and indicate the underlying tumor type. Recently, a new antibody against protein-kinase Cγ (PKCγ) was detected in a patient with paraneoplastic cerebellar degeneration (PCD). We report here a second patient. A 70-year-old woman presented with cerebellar ataxia, dysdiadochokinesia, and dysarthria. Her serum showed immunoreactivity against the cytoplasm, dendrites and axons of Purkinje cells in tissue-based screening, later confirmed by immunoblot and phage plaques as anti-PKCγ. Tumor search revealed an adenocarcinoma of hepatobiliary origin. Detection of PKCγ antibodies should be considered in PCD and adenocarcinoma without typical onconeural antibodies.

Deterioration of anti-Yo-associated paraneoplastic cerebellar degeneration.

OBJECTIVES: Usually, the course of paraneoplastic cerebellar degeneration(PCD) is stable or progresses only slowly. Sudden marked progression after several years, as in the following case, has not been reported. CASE REPORT: After a 57 year old female had developed diplopia, cerebellar signs, upper-limb weakness, and bilateral stocking-type hypoesthesia, and Yo-antibodies were positive, PCD and sensory polyneuropathy were diagnosed. Upon further diagnostic work-up ovarian cancer FIGO-IIC was detected and treated with ovarectomy, hysterectomy, omentectomy, and chemotherapy. Within the following years she experienced several relapses and developed multifocal metastasis requiring surgery, various chemotherapies, thermocoagulations, and radiotherapy. During the first years, PCD showed only minor progression. After 5 years, however, asymmetric ataxia and dysarthria acutely deteriorated such that she became severely handicapped and dependent on the help of others. Several cycles of immunoglobulines were ineffective and she died at age 64 years in a severely disabled state without recovery of the PCD. CONCLUSIONS: PCD, which usually progresses only slowly, can acutely deteriorate without recovery.

VGCC antibody-positive paraneoplastic cerebellar degeneration presenting with positioning vertigo.

A 70-year-old woman developed paraneoplastic cerebellar degeneration (PCD) due to P/Q-type and N-type voltage-gated calcium channel antibodies and small cell lung cancer, the main clinical manifestations of which were severe positioning vertigo and vomiting. Loss of the visual suppression of caloric nystagmus, spontaneous downbeat nystagmus, periodic alternating nystagmus, and positioning vertigo in our patient most probably corresponds to the cerebellar flocculus/paraflocculus lesion caused by PCD.

ZIC antibodies in paraneoplastic cerebellar degeneration and small cell lung cancer.

Patients with isolated ZIC4 antibodies usually have paraneoplastic cerebellar degeneration (PCD) and small cell lung cancer (SCLC) but the frequency is unknown. We analyzed the presence of ZIC1, ZIC2 and ZIC4 antibodies in 27 patients with PCD and SCLC negative for other onconeural antibodies. ZIC antibodies were detected in nitrocellulose filters with phage plaques. Four (15%) PCD sera recognized ZIC2. Three of these positive sera also reacted with ZIC1 and two with ZIC4. Our study suggests that 1) the incidence of isolated ZIC antibodies is low in PCD patients and SCLC and 2) ZIC antibodies are probably directed to epitopes shared by the three ZIC proteins.

Antibodies to cerebellar nerve fibres in two patients with paraneoplastic cerebellar ataxia.

The aim of this study was to characterize two new atypical anti-neuronal antibodies using an immunohistochemical method on rat cerebellum and Western blot techniques with primate cerebellar tissue and with recombinant neuronal proteins. Atypical sera from two patients with paraneoplastic neurological syndromes associated with different tumours were detected. Case number 1 presented cerebellar degeneration and Merkel cell carcinoma and case number 2 paraneoplastic brainstem encephalitis and malignant fibrous histiocytoma. By immunohistochemistry, the two new atypical antibodies showed a similar fibrillar positivity in the molecular and granular layers and around the Purkinje cells. The dot blot with recombinant neuronal proteins (HuD, NOVA-1, CDR62/Yo, Amphiphysin) was negative, whereas the Western blot with neuronal antigens of primate cerebellum identified two different proteins with molecular weights (64 kD in case number 1, and 70 kD in case number 2). In conclusion, the two new antibody reactivities against nerve fibres should be integrated into the diagnostic paraneoplastic neurological syndromes guidelines.

Anti-Yo antibody-mediated paraneoplastic cerebellar degeneration in a man with esophageal adenocarcinoma.

We report a case of paraneoplastic cerebellar degeneration (PCD) associated with adenocarcinoma of the esophagus and anti-Yo antibodies in a male patient. The patient presented with progressive ataxia, dysarthria, and significant weight loss. Extensive work-up suggested paraneoplastic neurologic syndrome. A wide search for a cancer was undertaken and a small mass was identified in the distal esophagus on upper endoscopy. Biopsies of this lesion revealed well-differentiated invasive adenocarcinoma of the esophagus. The endoscopic ultrasound staged the tumor as T3N1M0. Despite trials of multiple therapeutic modalities, the patient's cerebellar dysfunction progressed. This is only the second report of PCD caused by esophageal adenocarcinoma and the fourth report of anti-Yo antibodies occurring in a male patient.

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.

Antibody types and IgG subclasses in paraneoplastic neurological syndromes.

Three major patterns of antineuronal antibody response have been identified in patients with paraneoplastic neurological syndromes: Type I ('Anti-Yo'), associated with cerebellar degeneration in the setting of breast or gynecological cancer, Type IIa ('anti-Hu') associated with encephalomyeloneuritis in patients with small cell carcinoma of the lung, and Type IIb ('anti-Ri') associated with breast cancer. We have employed immunofluorescence methods to determine the antibody classes and the IgG subclasses which react with neurons in each of these patterns of paraneoplastic antibody response. In this study, IgG was the only antibody class identified; IgM and IgA antibodies were not found. IgG1 was the major subclass represented and was found in 9/9 patients with Type I antibody response, 26/27 patients with Type IIa antibody response, and 3/3 patients with Type IIb antibody response. Many patients also exhibited positive staining for IgG2 and IgG3. Trace amounts of IgG4 antineuronal antibodies were detected in a single patient with Type I antibody response; IgG4 antibodies were not found in other patients. Patients with paraneoplastic neurological syndromes exhibit an antibody response which is overwhelmingly IgG and is comprised predominantly of IgG subclasses capable of fixing complement. The role of these antibodies in the pathogenesis of paraneoplastic neurological disease remains uncertain.

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.