Paraneoplastic encephalomyeloradiculits with multiple autoantibodies against ITPR-1, GFAP and MOG: case report and literature review

Anti-aquaporin-4 immunoglobulin G/anti-myelin oligodendrocyte glycoprotein immunoglobulin G double-positive paraneoplastic neurological syndrome in a patient with triple-negative breast cancer

We report a rare case of paraneoplastic neurological syndrome with dual seropositivity of anti-aquaporin-4 and myelin oligodendrocyte glycoprotein antibodies in a 40 year-old woman with metastatic triple-negative breast cancer. She received multiple lines of anti-neoplastic treatment, including immunotherapy with pembrolizumab, as well as cytotoxic chemotherapy. Paraneoplastic meningoencephalomyelitis developed 2 years after diagnosis of breast cancer and 1 year after discontinuation of immunotherapy with pembrolizumab. She first developed longitudinally extending transverse myelitis followed by left optic neuritis and meningoencephalitis with new enhancing lesions in the brain and spinal leptomeninges. Cerebrospinal fluid analysis during both episodes showed normal glucose and protein, and elevated white blood cell count. Cytology was negative for malignancy. Cerebrospinal fluid was positive for neuromyelitis optica immunoglobulin G antibody anti-aquaporin-4, and autoimmune myelopathy panel was positive for myelin oligodendrocyte glycoprotein antibody. The patient had significant clinical and radiographic improvement after completion of five cycles of plasmapheresis followed by intravenous immunoglobulin. She did not have recurrence of paraneoplastic syndrome with maintenance rituximab every 6 months and daily low-dose prednisone. She succumbed to progressive systemic metastatic disease 4.5 years after her breast cancer diagnosis. This case shows that these antibodies can occur concurrently and cause clinical features, such as both neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody disease, in a patient with a singular type of cancer. We highlight the importance of testing for paraneoplastic etiology in cancer patients with radiographic menigoencephalomyelitis or meningitis with atypical symptoms of meningeal carcinomatosis and/or cerebrospinal fluid profile negative for leptomeningeal carcinomatosis.

Epidemiology of paraneoplastic neurologic syndromes

Paraneoplastic neurologic syndromes (PNS), initially depicted as seemingly cryptic remote manifestations of malignancy, were first described clinically in the early 20th century, with pathophysiologic correlates becoming better elucidated in the latter half of the century. There remain many questions not only about the pathophysiology but also regarding the epidemiology of these conditions. The continuous discovery of novel autoantigens and related neurologic disease has broadened the association in classical PNS to include conditions such as paraneoplastic cerebellar degeneration. It has also brought into focus several other neurologic syndromes with a putative neoplastic association. These conditions are overall rare, making it difficult to capture large numbers of patients to study, and raising the question of whether incidence is increasing over time or improved identification is driving the increased numbers of cases. With the rise and increasing use of immunotherapy for cancer treatment, the incidence of these conditions is additionally expected to rise and may present with various clinical symptoms. As we enter an era of clinical trial intervention in these conditions, much work is needed to capture more granular data on population groups defined by socioeconomic characteristics such as age, ethnicity, economic resources, and gender to optimize care and clinical trial planning.

Antibodies to neural cell surface and synaptic proteins in paraneoplastic neurologic syndromes

Among patients with paraneoplastic neurologic syndromes (PNS), emphasis has historically been placed on neural antibodies against intracellular proteins that have a strong association with malignancy. Because of the intracellular location of their antigenic targets, these antibodies are typically considered to be non-pathogenic surrogate markers of immune cell-mediated neural injury. Unfortunately, patients with these antibodies often have suboptimal response to immunotherapy and poor prognosis. Over the last two decades, however, dramatic advancements have been made in the discovery and clinical characterization of neural antibodies against extracellular targets. These antibodies are generally considered to be pathogenic, given their potential to directly alter antigen structure or function, and patients with these antibodies often respond favorably to prompt immunotherapy. These antibodies also associate with tumors and may thus occur as PNS, albeit more variably than neural antibodies against intracellular targets. The updated 2021 PNS diagnostic criteria, which classifies antibodies as high-risk, intermediate-risk, or lower-risk for an associated cancer, better clarifies how neural antibodies against extracellular targets relate to PNS. Using this recently created framework, the clinical presentations, ancillary test findings, oncologic associations, and treatment responses of syndromes associated with these antibodies are discussed.

Investigating the association between neoplasms and MOG antibody-associated disease

Introduction

The association of myelin oligodendrocyte glycoprotein (MOG) antibody associated disease (MOGAD) and tumors has seldom been reported. We aim to investigate the occurrence of tumors in a cohort of patients with MOGAD and to describe their clinical features, in addition to previously reported cases.

Methods

We retrospectively identified patients with MOGAD (i.e., compatible clinical phenotype and positive MOG antibodies analysed with a live cell-based assay) from 1/1/2015 to 1/1/2023 who had a neoplasm diagnosed within 2  years from MOGAD onset. Furthermore, we performed systematic review of literature to identify previously reported cases. Clinical, paraclinical and oncological findings were collected and reported as median (range) or number (percentage).

Results

Two of 150 MOGAD patients (1%) had a concomitant neoplasm in our cohort. Fifteen additional cases were retrieved from literature. Median age was 39 (16-73) years-old, 12 patients were female. ADEM (n = 4;23.5%), encephalomyelitis (n = 3;17.6%), and monolateral optic neuritis (n = 2;11.8%) were the most frequent phenotypes. Median number of treatments was 1 (range 1-4), improvement was reported in 14/17 cases (82.4%). Oncological accompaniments were teratoma (n = 4), CNS (n = 3), melanoma (n = 2), lung (n = 2), hematological (n = 2), ovary (n = 1), breast (n = 1), gastrointestinal (n = 1), and thymic (n = 1) neoplasms. Median time from tumor diagnosis to MOGAD onset was 0 (range - 60 to 20) months. MOG expression in neoplastic tissue was reported in 2/4 patients. Median PNS-CARE score was 3 (range 0-7): 11 patients were classified as "non-PNS," 5 as "possible PNS," and 1 as "probable PNS."

Discussion

Our study confirms that MOG is a low-risk antibody for paraneoplastic neurological syndromes and that the clinical presentation and oncological accompaniments are extremely variable. Most of these patients were classified as non-PNS, whereas only a minority was diagnosed with possible/probable PNS, frequently in association with ovarian teratoma. These findings support the notion that MOGAD is not a paraneoplastic disease.

Two Cases of Juvenile Myelomonocytic Leukemia and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an autoimmune demyelinating disorder that often manifests after infections or vaccinations. We report two patients who developed MOGAD out of eight patients with juvenile myelomonocytic leukemia (JMML) that has never been reported.

METHODS

We investigated two patients with JMML who developed MOGAD among 127 patients with leukemia from 2012 to 2021.

RESULTS

Patient 1 was treated for JMML and developed fever and impaired consciousness at two years and one month of age. Magnetic resonance imaging revealed high-intensity lesions in the left frontal and left occipital white matter. The serum anti-MOG antibody test was positive, while the test was negative in the stored serum 45 days before the onset of encephalopathy. He had relapse of MOGAD after steroid therapy and plasmapheresis. Patient 2, who was treated for JMML, became apathetic and mute at three years and seven months of age. Magnetic resonance imaging revealed left frontoparietal subcortical high-intensity lesions. Anti-MOG antibody at the onset of encephalopathy was positive, while it was negative in stored serum 57 days before and 47 days after the onset.

CONCLUSION

We treated two patients who developed MOGAD out of eight patients with JMML and none with MOGAD out of 119 patients with acute lymphocytic leukemia, acute myelocytic leukemia, or chronic myelocytic leukemia. The activated autoimmune process via the RAS pathway abnormality may have led to the formation of the anti-MOG antibody and the onset of MOGAD. MOGAD can occur in children with JMML, and abnormalities of the RAS pathway possibly contribute to its onset.

Autoimmune diseases and cancers overlapping with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): A systematic review

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has various similarities with AQP4-IgG-seropositive Neuromyelitis Optica Spectrum Disorder (AQP4-IgG + NMOSD) in terms of clinical presentations, magnetic resonance imaging (MRI) findings, and response to treatment. But unlike AQP4-IgG + NMOSD, which is known to coexist with various autoimmune diseases and cancers, an association of MOGAD with these conditions is less clear.

Methods

We conducted a systematic search in PubMed, Scopus, Web of Science, and Embase based on the preferred reporting items for systematic reviews and meta-analysis (PRISMA). Duplicates were removed using Mendeley 1.19.8 (USA production) and the citations were uploaded into Covidence systematic review platform for screening.

Results

The most common autoimmune disease overlapping with MOGAD was anti-N-Methyl-D-Aspartate receptor encephalitis (anti-NMDAR-EN), followed by autoimmune thyroid disorders, and the most common autoantibody was antinuclear antibody (ANA), followed by AQP4-IgG (double-positive MOG-IgG and AQP4-IgG). A few sporadic cases of cancers and MOG-IgG-associated paraneoplastic encephalomyelitis were found.

Conclusion

Unlike AQP4-IgG + NMOSD, MOGAD lacks clustering of autoimmune diseases and autoantibodies associated with systemic and organ-specific autoimmunity. Other than anti-NMDAR-EN and perhaps AQP4-IgG + NMOSD, the evidence thus far does not support the need for routine screening of overlapping autoimmunity and neoplasms in patients with MOGAD.

Inositol 1,4,5-trisphosphate receptor type 1 autoantibody (ITPR1-IgG/anti-Sj)-associated autoimmune cerebellar ataxia, encephalitis and peripheral neuropathy: review of the literature

Background

In 2014, we first described novel autoantibodies to the inositol 1,4,5-trisphosphate receptor type 1 (ITPR1-IgG/anti-Sj) in patients with autoimmune cerebellar ataxia (ACA) in this journal. Here, we provide a review of the available literature on ITPR1-IgG/anti-Sj, covering clinical and paraclinical presentation, tumour association, serological findings, and immunopathogenesis.

Methods

Review of the peer-reviewed and PubMed-listed English language literature on ITPR1-IgG/anti-Sj. In addition, we provide an illustrative report on a new patient with ITPR1-IgG-associated encephalitis with cognitive decline and psychosis.

Results

So far, at least 31 patients with serum ITPR1-IgG/anti-Sj have been identified (clinical information available for 21). The most common manifestations were ACA, encephalopathy with seizures, myelopathy, and (radiculo)neuropathy, including autonomic neuropathy. In 45% of cases, an underlying tumour was present, making the condition a facultative paraneoplastic neurological disorder. The neurological syndrome preceded tumour diagnosis in all but one case. In most cases, immunotherapy had only moderate or no effect. The association of ITPR1-IgG/anti-Sj with manifestations other than ACA is corroborated by the case of a 48-year-old woman with high-titre ITPR1-IgG/anti-Sj antibodies and rapid cognitive decline, affecting memory, attention and executive function, and psychotic manifestations, including hallucinations, investigated here in detail. FDG-PET revealed right-temporal glucose hypermetabolism compatible with limbic encephalitis. Interestingly, ITPR1-IgG/anti-Sj mainly belonged to the IgG2 subclass in both serum and cerebrospinal fluid (CSF) in this and further patients, while it was predominantly IgG1 in other patients, including those with more severe outcome, and remained detectable over the entire course of disease. Immunotherapy with intravenous methylprednisolone, plasma exchange, and intravenous immunoglobulins, was repeatedly followed by partial or complete recovery. Long-term treatment with cyclophosphamide was paralleled by relative stabilization, although the patient noted clinical worsening at the end of each treatment cycle.

Conclusions

The spectrum of neurological manifestations associated with ITPR1 autoimmunity is broader than initially thought. Immunotherapy may be effective in some cases. Studies evaluating the frequency of ITPR1-IgG/anti-Sj in patients with cognitive decline and/or psychosis of unknown aetiology are warranted. Tumour screening is essential in patients presenting with ITPR1-IgG/anti-Sj.

Coexistence of Myelin Oligodendrocyte Glycoprotein Immunoglobulin G and Neuronal or Glial Antibodies in the Central Nervous System: A Systematic Review

Background: Myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG) has been considered a diagnostic marker for patients with demyelinating disease, termed “MOG-IgG associated disorder” (MOGAD). Recently, the coexistence of MOG-IgG and other neuronal or glial antibodies has attracted extensive attention from clinicians. In this article, we systematically review the characteristics of MOG-IgG-related antibody coexistence syndrome. Methods: Two authors independently searched PubMed for relevant studies published before October 2021. We also manually searched the references of each related article. The appropriateness of the included studies was assessed by reading the titles, abstracts, and full texts if necessary. Results: Thirty-five relevant publications that met our inclusion criteria were finally included, of which fourteen were retrospective studies and twenty-one were case reports. A total of 113 patients were reported to show the coexistence of MOG-IgG and neuronal or glial antibodies. Additionally, 68.14% of patients were double positive for MOG-IgG and N-Methyl-D-Aspartate Receptor-IgG (NMDAR-IgG), followed by 23.01% of patients who were double positive for MOG-IgG and aquaporin4-IgG (AQP4-IgG). Encephalitis was the predominant phenotype when MOG-IgG coexisted with NMDAR-IgG, probably accompanied by imaging features of demyelination. Patients with dual positivity for MOG-IgG and AQP4-IgG experienced more severe disease and more frequent relapses. The coexistence of MOG-IgG and antibodies other than NMDAR-IgG and AQP4-IgG was extremely rare, and the clinical presentations were diverse and atypical. Except for patients who were double positive for MOG-IgG and AQP4-IgG, most patients with multiple antibodies had a good prognosis. Conclusions: MOG-IgG may coexist with neuronal or glial antibodies. Expanded screening for neuronal or glial antibodies should be performed in patients with atypical clinical and radiological features.

Novel Antibody-Peptide Binding Assay Indicates Presence of Immunoglobulins against EGFR Phospho-Site S1166 in High-Grade Glioma

We investigated the feasibility of detecting the presence of specific autoantibodies against potential tumor-associated peptide antigens by enriching these antibody-peptide complexes using Melon Gel resin and mass spectrometry. Our goal was to find tumor-associated phospho-sites that trigger immunoreactions and raise autoantibodies that are detectable in plasma of glioma patients. Such immunoglobulins can potentially be used as targets in immunotherapy. To that aim, we describe a method to detect the presence of antibodies in biological samples that are specific to selected clinically relevant peptides. The method is based on the formation of antibody-peptide complexes by mixing patient plasma with a glioblastoma multiforme (GBM) derived peptide library, enrichment of antibodies and antibody-peptide complexes, the separation of peptides after they are released from immunoglobulins by molecular weight filtration and finally mass spectrometric quantification of these peptides. As proof of concept, we successfully applied the method to dinitrophenyl (DNP)-labeled α-casein peptides mixed with anti-DNP. Further, we incubated human plasma with a phospho-peptide library and conducted targeted analysis on EGFR and GFAP phospho-peptides. As a result, immunoaffinity against phospho-peptide GSHQIS[+80]LDNPDYQQDFFPK (EGFR phospho-site S1166) was detected in high-grade glioma (HGG) patient plasma but not in healthy donor plasma. For the GFAP phospho-sites selected, such immunoaffinity was not observed.