The diagnostic utility of myositis autoantibody testing for predicting the risk of cancer-associated myositis

Causality Assessment Between Idiopathic Inflammatory Myopathies and Lung Cancer: A Bidirectional 2-Sample Mendelian Randomization

BACKGROUND

Although observational studies have revealed associations between idiopathic inflammatory myopathies (IIMs) and lung cancer (LC), they have not established a causal relationship between these 2 conditions.

METHODS

We used a 2-sample Mendelian randomization approach to examine the bidirectional causal associations between IIMs and LC, using single-nucleotide polymorphisms selected from high-quality genome-wide association studies in the FinnGen database. Sensitivity analyses were conducted to assess potential heterogeneity and pleiotropy impacts on the Mendelian randomization results.

RESULTS

Our analysis demonstrated a positive causal effect of genetically increased IIM risk on LC (odds ratio, 1.114; 95% confidence interval, 1.057-1.173; p = 5.63 × 10 -5 ), particularly on the lung squamous cell carcinoma subtype (odds ratio, 1.168, 95% confidence interval, 1.049-1.300, p = 0.00451), but not on lung adenocarcinoma or small cell lung cancer. No causal effect of LC on IIMs was identified. Sensitivity analyses indicated that horizontal pleiotropy was unlikely to influence causality, and leave-one-out analysis confirmed that the observed associations were not driven by a single-nucleotide polymorphism.

CONCLUSION

Our findings offer compelling evidence of a positive causal relationship between IIMs and LC, particularly with regard to lung squamous cell carcinoma, in the European population. Conversely, there is no evidence of LC causing IIMs. We recommend that LC diagnosis consider the specific characteristics of IIMs.

Combination of Sjögren's syndrome and anti-Ku syndrome complicated by the development of mucosa-associated lymphoid tissue lymphoma: case review and systematic review of the literature

The frequency of antibodies to Ku varies in various autoimmune diseases. In 2019, Spielmann et al. identified two types of anti-Ku syndrome based on a hierarchical clustering analysis. Sjögren's syndrome occurs both in the first type of anti-Ku syndrome and in the second type. Despite the fact that increased tissue expression of Ku proteins was noted in lymphocytic cells with focal sialoadenitis of the minor salivary glands in patients with primary Sjogren's syndrome, only 49 cases of a combination of anti-Ku antibodies and manifestations of Sjogren's syndrome have been described in the literature. Some researchers examined patients for the presence of Sjogren's syndrome only if they had anti-Ro or anti-La antibodies, although in the literature, there are descriptions of Sjogren's syndrome in the presence of only isolated anti-Ku antibodies, as in our case. Literature data on glandular and extraglandular manifestations of Sjögren's syndrome in anti-Ku-positive patients are limited. Below, we present the first case of Sjögren's syndrome in combination with the first type of anti-Ku syndrome complicated by the development of mucosa-associated lymphoid tissue (MALT) lymphoma. The article also provides a systematic review of the literature on the association of Sjögren's syndrome with anti-Ku antibodies.

Anti-PL-7, anti-Ro/SSA, anti-Mi-2, and anti-TIF1-γ correlate with specific patterns of histopathologic features in dermatomyositis: An analysis of 39 skin biopsy specimens from 25 patients

BACKGROUND

In dermatomyositis (DM), myositis-specific and myositis-associated antibodies have been correlated with clinical features. It is unknown if histopathologic findings in lesional skin biopsies correlate with serologic subtypes of DM.

METHODS

A retrospective chart review of patients with DM was performed. Patients with myositis antibodies and DM lesional skin biopsies were included in the study. Skin biopsies were reviewed by blinded dermatopathologists for 20 histopathologic features.

RESULTS

There was a statistically significant (p < 0.05) association between anti-PL-7 serology and decreased degree of vacuolar degeneration, necrotic keratinocytes, and thickening of the epidermal basement membrane. Anti-aminoacyl tRNA synthetase (anti-ARS) antibodies had the same significant negative association with degree of vacuolar degeneration, necrotic keratinocytes, and thickening of the epidermal basement membrane. A similar pattern was seen with an anti-cytoplasmic serology; where there was a significant association with an increased degree of vacuolar degeneration and necrotic keratinocytes, and a nonsignificant trend of minimally thickened epidermal basement membrane. There was a statistically significant association between anti-Ro/SSA serology and increased degree of vacuolar degeneration. Anti-TIF1-γ serology was significantly associated with the increased presence of necrotic keratinocytes and pigment incontinence, and displayed a pattern of increased neutrophils. There was a significant association between anti-Mi-2 antibodies and pigment incontinence, as well as between myositis-specific antibodies and pigment incontinence. A statistically significant positive association was found between nuclear antibodies and degree of vacuolar degeneration, thickened epidermal basement membrane, pigment incontinence, and epidermal atrophy.

CONCLUSION

In patients with DM, some specific serotypes, including anti-PL-7, anti-Ro/SSA, anti-Mi-2, and anti-TIF1-γ, may have characteristic histopathologic features.

Novel endotypes of antisynthetase syndrome identified independent of anti-aminoacyl transfer RNA synthetase antibody specificity that improve prognostic stratification

OBJECTIVES

To systemically analyse the heterogeneity in the clinical manifestations and prognoses of patients with antisynthetase syndrome (ASS) and evaluate the transcriptional signatures related to different clinical phenotypes.

METHODS

A total of 701 patients with ASS were retrospectively enrolled. The clinical presentation and prognosis were assessed in association with four anti-aminoacyl transfer RNA synthetase (ARS) antibodies: anti-Jo1, anti-PL7, anti-PL12 and anti-EJ. Unsupervised machine learning was performed for patient clustering independent of anti-ARS antibodies. Transcriptome sequencing was conducted in clustered ASS patients and healthy controls.

RESULTS

Patients with four different anti-ARS antibody subtypes demonstrated no significant differences in the incidence of rapidly progressive interstitial lung disease (RP-ILD) or prognoses. Unsupervised machine learning, independent of anti-ARS specificity, identified three endotypes with distinct clinical features and outcomes. Endotype 1 (RP-ILD cluster, 23.7%) was characterised by a high incidence of RP-ILD and a high mortality rate. Endotype 2 (dermatomyositis (DM)-like cluster, 14.5%) corresponded to patients with DM-like skin and muscle symptoms with an intermediate prognosis. Endotype 3 (arthritis cluster, 61.8%) was characterised by arthritis and mechanic's hands, with a good prognosis. Transcriptome sequencing revealed that the different endotypes had distinct gene signatures and biological processes.

CONCLUSIONS

Anti-ARS antibodies were not significant in stratifying ASS patients into subgroups with greater homogeneity in RP-ILD and prognoses. Novel ASS endotypes were identified independent of anti-ARS specificity and differed in clinical outcomes and transcriptional signatures, providing new insights into the pathogenesis of ASS.

Paraneoplastic Cerebellar Degeneration Associated with Breast Cancer: A Case Report and a Narrative Review

Paraneoplastic neurological syndromes (PNSs) are an uncommon complication of cancer, affecting nearby 1/10,000 subjects with a tumour. PNSs can involve all the central and peripheral nervous systems, the muscular system, and the neuromuscular junction, causing extremely variable symptomatology. The diagnosis of the paraneoplastic disease usually precedes the clinical manifestations of cancer, making an immediate recognition of the pathology crucial to obtain a better prognosis. PNSs are autoimmune diseases caused by the expression of common antigens by the tumour and the nervous system. Specific antibodies can help clinicians diagnose them, but unfortunately, they are not always detectable. Immunosuppressive therapy and the treatment of cancer are the cornerstones of therapy for PNSs. This paper reports a case of PNSs associated with breast tumours and focuses on the most common paraneoplastic neurological syndromes. We report a case of a young female with a clinical syndrome of the occurrence of rigidity in the right lower limb with postural instability with walking supported and diplopia, with a final diagnosis of paraneoplastic cerebellar degeneration and seronegative rigid human syndrome associated with infiltrating ductal carcinoma of the breast.

Comparison of characteristics and anti-MDA5 antibody distribution and effect between clinically amyopathic dermatomyositis and classic dermatomyositis: a retrospective case-control study

Background

Clinically amyopathic dermatomyositis (CADM) is a distinct subtype of dermatomyositis (DM) characterized by typical DM cutaneous findings but with minimal or no evidence of myositis. It possesses unique features different from classic DM (CDM). Anti-melanoma differentiation-associated gene 5 (MDA5) antibodies were found in CADM and are thought to increase the risk of rapidly progressive interstitial lung disease (RP-ILD) and are present in both CADM and CDM patients, affecting their condition and prognosis. Nevertheless, no large-sample studies have compared all aspects concerning patients with CADM and those with CDM. This study aimed to investigate differences in clinical characteristics and risk factors for mortality between CADM and CDM and to clarify the distribution and impact of anti-MDA5 antibodies in patients with these conditions.

Methods

A retrospective case-control study included 330 patients and collected and analyzed their clinical data from The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Hospital of Traditional Chinese Medicine between January 2015 and July 2022; all patients were followed up to evaluate changes in their condition and prognosis. Several new cohorts were designed around anti-MDA5 antibodies to explore their distribution and impact in CADM and CDM.

Results

We found CADM to be associated with higher rates of mortality, 1-year mortality, interstitial lung disease (ILD), and RP-ILD than CDM. In CADM, RP-ILD, anti-MDA5 antibodies, and high ferritin and lactate dehydrogenase (LDH) levels were identified as independent risk factors for death. In CDM, the neutrophil-to-lymphocyte ratio, anti-MDA5 antibodies, and high ferritin levels were shown to be independent risk factors for death, whereas mechanic's hand was considered a protective factor against it. Anti-MDA5 antibody-positive patients did not exhibit any significant difference based on whether they belonged to the CADM or CDM groups. When no anti-MDA5 antibody-positive patients participated, the ferritin levels and rates of RP-ILD and ILD were still higher in CADM than in CDM; however, such differences decreased, whereas the LDH levels, rates of mortality, and 1-year mortality did not differ. Anti-MDA5 antibody-positive patients consistently showed higher LDH and ferritin levels, lower lymphocyte levels, higher probability of RP-ILD and ILD, and worse prognosis than anti-MDA5 antibody-negative patients, irrespective of whether the patients had DM, CADM, or CDM.

Conclusion

Patients with CADM exhibit relatively worse symptoms, serological findings, and prognosis than those with CDM. Furthermore, patients with CADM and those with CDM have commonalities and differences in risk factors for death. Moreover, CADM may necessitate earlier and more aggressive treatment strategies than CDM. Anti-MDA5 antibodies occur at a high level in patients with CADM, not only affecting the symptoms and prognosis of DM but also having a non-negligible impact on the differences between CADM and CDM. Hence, screening for anti-MDA5 antibodies in patients with CADM and CDM is extremely essential.

Advances of autoimmune rheumatic diseases related to malignant tumors

BACKGROUND

Malignant neoplasms are a well-recognized global public health concern, with significant impacts on human health and quality of life. The interplay between tumors and autoimmune rheumatic diseases is complex, and the resulting tumor-associated rheumatic diseases represent a rare and intricate group of conditions that occur in the context of malignant tumors. In addition, various rheumatic diseases can arise as a consequence of oncology treatment. These diseases present with intricate clinical manifestations and pathological features, often rendering them challenging to diagnose and impacting patients' quality of life. Despite this, they have yet to be fully recognized.

METHODS

This article presents a literature review of published original articles and review articles concerning paraneoplastic rheumatic syndromes and rheumatic diseases associated with cancer treatment. We conducted a comprehensive literature search in PubMed, Web of Science and Google Scholar databases, excluding duplicated and irrelevant studies. In cases of duplicated research, we selected articles with higher impact factors for the review.

RESULTS

This review focuses on the clinical features, diagnosis, and treatment of paraneoplastic rheumatic diseases, as well as the pathogenesis of these diseases. Additionally, we summarize the autoimmune rheumatic diseases associated with cancer treatment. Ultimately, the goal of this review is to enhance recognition and improve the management of autoimmune rheumatic diseases related to tumors.

Diagnostic Yield of Computed Tomography for Cancer Detection in a Tertiary Referral Population of Idiopathic Inflammatory Myositis Patients

OBJECTIVE

To inform guidance for cancer detection in patients with idiopathic inflammatory myopathy (IIM), we evaluated the diagnostic yield of computed tomography (CT) imaging for cancer screening/surveillance within distinct IIM subtypes and myositis-specific autoantibody strata.

METHODS

We conducted a single-center, retrospective cohort study in IIM patients. Overall diagnostic yield (number of cancers diagnosed/number of tests performed), percentage of false positives (number of biopsies performed not leading to cancer diagnosis/number of tests performed), and test characteristics were determined on CT of the chest and abdomen/pelvis.

RESULTS

Within the first 3 years since IIM symptom onset, a total of 9 of 1,011 (0.9%) chest CT scans and 12 of 657 (1.8%) abdomen/pelvis CT scans detected cancer. Diagnostic yields for both CT of the chest and CT of the abdomen/pelvis were highest in dermatomyositis, specifically anti-transcription intermediary factor 1γ (2.9% and 2.4% for CT of the chest and abdomen/pelvis, respectively). The highest percentage of false positives was in patients with antisynthetase syndrome (ASyS) (4.4%) and immune-mediated necrotizing myopathy (4.4%) on CT of the chest, and ASyS (3.8%) on CT of the abdomen/pelvis. Patients ages <40 years old at IIM onset had both low diagnostic yields (0% and 0.5%) and high false-positive rates (1.9% and 4.4%) for CT of the chest and abdomen/pelvis, respectively.

CONCLUSION

In a tertiary referral cohort of IIM patients, CT imaging has a wide range of diagnostic yield and frequency of false positives for contemporaneous cancer. These findings suggest that cancer detection strategies targeted according to IIM subtype, autoantibody positivity, and age may maximize cancer detection while minimizing the harms and costs of over-screening.

Clinical pearls and promising therapies in myositis

INTRODUCTION

Idiopathic inflammatory myopathies (IIMs) represent a diverse group of systemic autoimmune disorders with variable clinical manifestations and disease course. Currently, the challenges of IIMs are multifold, including difficulties in timely diagnosis owing to clinical heterogeneity, limited insights into disease pathogenesis, as well as a restricted number of available therapies. However, advances utilizing myositis-specific autoantibodies (MSAs) have facilitated the definition of subgroups as well as prediction of clinical phenotypes, disease course, and response to treatment.

AREAS COVERED

Herein we provide an overview of the clinical presentations of dermatomyositis (DM), anti-synthetase syndrome (ASyS), immune-mediated necrotizing myopathy (IMNM) and inclusion body myositis (IBM). We then provide an updated review of available and promising therapies for each of these disease groups. We synthesize current treatment recommendations in the context of case-based construct to facilitate application to patient care. Finally, we provide high-yield, clinical pearls relevant to each of the subgroups that can be incorporated into clinical reasoning.

EXPERT OPINION

There are many exciting developments on the horizon for IIM. As insights into pathogenesis evolves, the therapeutic armamentarium is expanding with many novel therapies in development, holding promise for more targeted treatment approaches.

Subsets of Idiopathic Inflammatory Myositis Enriched for Contemporaneous Cancer Relative to the General Population

OBJECTIVE

This study investigates cancer risk in idiopathic inflammatory myopathy (IIM) relative to the general population.

METHODS

We conducted a single-center, retrospective cohort study of IIM patients and malignancy. Myositis-specific and -associated autoantibodies were determined by Euroimmun line blot, enzyme-linked immunosorbent assay, and immunoprecipitation. We calculated standardized prevalence ratios (SPRs) and adjusted for calendar year, age, sex, race, and ethnicity by comparing observed cancers in IIM patients versus expected cancers in the general population using the Surveillance, Epidemiology, and End Results registry.

RESULTS

Of 1,172 IIM patients, 203 (17%) patients with a cancer history were studied. Over a median follow-up of 5.2 years, the observed number of IIM patients diagnosed with cancer was increased 1.43-fold (SPR 1.43 [95% confidence interval (95% CI) 1.15-1.77]; P = 0.002). Within 3 years of IIM symptom onset, an increased SPR was observed for anti-transcription intermediary factor 1γ (anti-TIF1γ)-positive patients for ovarian and breast cancer (ovarian SPR 18.39 [95% CI 5.01-47.08], P < 0.001; breast SPR 3.84 [95% CI 1.99-6.71], P < 0.001). As expected, anti-TIF1γ positivity was associated with a significantly elevated SPR; however, only 55% (36 of 66) of all cancers within 3 years of dermatomyositis onset were observed in anti-TIF1γ-positive patients. Other myositis-specific autoantibodies, including anti-Mi-2, anti-small ubiquitin-like modifier activating enzyme (SAE), and anti-nuclear matrix protein 2 (NXP-2), accounted for 26% (17 of 66) of cancers diagnosed within 3 years of dermatomyositis onset. No cancer association, positive or negative, was observed for patients with antisynthetase, anti-melanoma differentiation-associated protein 5 (anti-MDA-5), or anti-hydroxymethylglutaryl-coenzyme A reductase (anti-HMGCR) antibodies.

CONCLUSION

In a tertiary referral center population, anti-TIF1γ was most strongly associated with breast and ovarian cancer. Patients with antisynthetase, anti-MDA-5, or anti-HMGCR antibodies had the same cancer risk as the general population.

Predictors of cardiac involvement in idiopathic inflammatory myopathies

Objectives

Idiopathic inflammatory myopathies (IIM) are a group of rare disorders that can affect the heart. This work aimed to find predictors of cardiac involvement in IIM.

Methods

Multicenter, open cohort study, including patients registered in the IIM module of the Rheumatic Diseases Portuguese Register (Reuma.pt/Myositis) until January 2022. Patients without cardiac involvement information were excluded. Myo(peri)carditis, dilated cardiomyopathy, conduction abnormalities, and/or premature coronary artery disease were considered.

Results

230 patients were included, 163 (70.9%) of whom were females. Thirteen patients (5.7%) had cardiac involvement. Compared with IIM patients without cardiac involvement, these patients had a lower bilateral manual muscle testing score (MMT) at the peak of muscle weakness [108.0 ± 55.0 vs 147.5 ± 22.0, p=0.008] and more frequently had oesophageal [6/12 (50.0%) vs 33/207 (15.9%), p=0.009] and lung [10/13 (76.9%) vs 68/216 (31.5%), p=0.001] involvements. Anti-SRP antibodies were more commonly identified in patients with cardiac involvement [3/11 (27.3%) vs 9/174 (5.2%), p=0.026]. In the multivariate analysis, positivity for anti-SRP antibodies (OR 104.3, 95% CI: 2.5-4277.8, p=0.014) was a predictor of cardiac involvement, regardless of sex, ethnicity, age at diagnosis, and lung involvement. Sensitivity analysis confirmed these results.

Conclusion

Anti-SRP antibodies were predictors of cardiac involvement in our cohort of IIM patients, irrespective of demographical characteristics and lung involvement. We suggest considering frequent screening for heart involvement in anti-SRP-positive IIM patients.

Genetic Influences in Cancer-Associated Myositis

Idiopathic inflammatory myopathies (IIMs) comprise a heterogeneous group of rare immune-mediated disorders that primarily affect muscles but also lead to dysfunction in other organs. Five different clinical subphenotypes of IIM have been distinguished: dermatomyositis, polymyositis, inclusion body myositis, antisynthetase syndrome, and immune-mediated necrotizing myopathy. Excess mortality and morbidity associated with IIM are largely attributed to comorbidities, particularly cancer. The risk of malignancy is not equally distributed among IIM groups and is particularly high among patients with dermatomyositis. The cancer risk peaks around 3 years on either side of the IIM diagnosis and remains elevated even 10 years after the onset of the disease. Lung, colorectal, and ovarian neoplasms typically arise before the onset of IIM, whereas melanoma, cervical, oropharyngeal, and nonmelanoma skin cancers usually develop after IIM diagnosis. Given the close temporal proximity between IIM diagnosis and the emergence of malignancy, it has been proposed that IIM could be a consequence rather than a cause of cancer, a process known as a paramalignant phenomenon. Thus, a separate group of IIMs related to paramalignant phenomenon has been distinguished, known as cancer-associated myositis (CAM). Although the relationship between IIM and cancer is widely recognized, the pathophysiology of CAM remains elusive. Given that genetic factors play a role in the development of IIM, dissection of the molecular mechanisms shared between IIM and cancer presents an opportunity to examine the role of autoimmunity in cancer development and progression. In this review, the evidence supporting the contribution of genetics to CAM will be discussed.

Long-term risks of malignancy in myositis-specific antibody-positive idiopathic inflammatory myopathy

To identify the long-term risks of malignancy in patients with myositis-specific antibody (MSA)-positive idiopathic inflammatory myopathy (IIM). This retrospective cohort study included 216 IIM patients (aged > 18 years). Of these, 109 patients were positive for antibodies against anti-aminoacyl-tRNA synthetase (ARS), melanoma differentiation-associated gene 5 (MDA5), Mi-2, and transcriptional intermediary factor 1-γ (TIF1-γ). Age- and sex-matched standardized incidence ratios (SIRs) were calculated to compare the incidence of malignancy in IIM patients to that of the general population. The malignancy-free survival rate was estimated by Kaplan-Meier methods. Our study included 109 patients, 64 with anti-ARS, 28 with anti-MDA5, 9 with anti-Mi-2, and 8 with anti-TIF1-γ antibodies; 16 and 5 patients were diagnosed with a malignancy within 3 years before or after and within 4 to 10 years after their IIM onset, respectively. The SIRs of malignancy within 3 years of IIM onset for each MSA were calculated as follows: 2.12 (95% confidence interval [CI] 0.98-4.35) for anti-ARS, 1.87 (95% CI 0.48-4.97) for anti-MDA5, 2.11 (95% CI 0.11-13.69) for anti-Mi-2, and 9.30 (95% CI 2.98-25.58) for anti-TIF1-γ antibodies. The SIR at 4 to 10 years after IIM onset in patients with an anti-MDA5 antibody was 4.62 (95% CI 1.19-14.72); other MSAs did not have statistically significant SIRs. The long-term SIR of malignancy in patients with an anti-MDA5 antibody was 4.62 (95% CI 1.19-14.72), and the SIR among patients with an anti-TIF1-γ antibody within 3 years of IIM onset was 9.30 (95% CI 2.98-25.58). Screening for malignancies in patients with late phase of IIM and an anti-MDA5 antibody may be beneficial.

Circulating VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ as biomarkers of cancer in cancer-associated anti-TIF1-γ antibody-positive dermatomyositis

OBJECTIVES

The objective of the current study was to detect plasma profiles of inflammatory cytokines for determining potential biomarkers indicating cancer presence among the anti-TIF1-γ antibody-positive dermatomyositis (DM) patients.

METHODS

Twenty-seven cancer-associated anti-TIF1-γ antibody-positive DM (Cancer TIF1-γ-DM) patients were compared with 20 anti-TIF1-γ antibody-positive DM patients without cancer (Non-cancer TIF1-γ-DM) and 10 healthy controls (HC). The plasma levels of 17 cytokines were determined using the Luminex 200 system. The ability of plasma VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ levels to distinguish the presence of cancer was evaluated through the area under the curve (AUC) analysis. Potential protein interactions of TIF1-γ and the five cytokines were analyzed using the STRING database.

RESULTS

VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ plasma levels were significantly higher in the Cancer TIF1-γ-DM group, especially those without any anticancer treatment, than those in the non-cancer TIF1-γ-DM and HC groups. Meanwhile, anti-TIF1-γ antibody and the five cytokines could distinguish cancer presence in anti-TIF1-γ antibody-positive DM patients. The STRING network indicated that TIF1-γ potentially interacted with the cytokines. Positive correlations of VEGF-A among CCL2, IL-6, and IFN-γ and between IFN-γ and IL-6 were observed in Cancer TIF1-γ-DM patients. VEGF-A, TNF-α, CCL2, and IL-6 were positively associated with muscle-associated enzymes among the Cancer TIF1-γ-DM patients.

CONCLUSION

The present study identified VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ as significant potential biomarkers indicating the presence of cancer and demonstrated a more detailed cytokine profile during diagnosis. These biomarkers could provide better screening strategies and insight into the Cancer TIF1-γ-DM pathogenesis. Key Points • VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ are potential biomarkers of cancer in cancer-associated anti-TIF1-γ antibody-positive dermatomyositis. Potential pathogenic molecular mechanism of the cancer-associated anti-TIF1-γ antibody-positive dermatomyositis.

Characteristics of anti-transcriptional intermediary factor 1 gamma autoantibody-positive dermatomyositis patients in Singapore

Introduction: This study aimed to determine the clinical profile and outcome of anti-transcriptional intermediary factor 1 gamma autoantibody (anti-TIF1-γ Ab)-positive dermatomyositis patients and propose cancer screening programmes based on regional cancer trends. Method: Data on history, physical findings and investigations were collected using chart review on dermatomyositis patients seen at a tertiary hospital in Singapore from 1 January 2015 to 30 June 2021. Comparisons were made between anti-TIF1-γ Ab-positive and anti-TIF1-γ Ab-negative dermatomyositis. Results: Ninety-six dermatomyositis patients were analysed and 36 patients were positive for anti-TIF1-γ Ab. Anti-TIF1-γ Ab-positive patients had more frequent heliotrope rashes, shawl sign, periungual erythema, holster sign, Gottron’s papules, dysphagia and truncal weakness (P<0.05). They had less frequent interstitial lung disease, polyarthritis, cutaneous ulcers, palmar papules and mechanic’s hands (P<0.05). After 48 months of follow-up, a higher proportion of anti-TIF1-γ Ab-positive patients developed cancer compared with Ab-negative patients (63.9% versus 8.5%; odds ratio 19.1, 95% confidence interval 6.1–59.8; P<0.001). Nasopharyngeal carcinoma (NPC) and breast cancer were the most common malignancies, followed by bowel, lung and non-Hodgkin lymphoma. Most malignancies (78.3%) occurred within 13 months prior to, or 4 months after the onset of dermatomyositis. The mortality rate for anti-TIF1-γ Ab-positive patients was significantly higher than Ab-negative patients (36.1% vs 16.7%, P=0.031), and Kaplan-Meier survival estimates at 24 months were 66% and 89%, respectively (P=0.0153). Conclusion: These observational data support periodic screening of NPC and other malignancies in patients with anti-TIF1-γ Ab-positive dermatomyositis in Singapore. Keywords: Autoantibody, cancer, dermatomyositis, nasopharyngeal carcinoma, transcriptional intermediary factor 1 gamma

Prevalence of Myositis-Specific Autoantibodies and Myositis-Associated Autoantibodies in COVID-19 Patients: A Pilot Study and Literature Review

Coronavirus disease 2019 (COVID-19) infection has been linked to numerous autoimmune manifestations. Neither the mechanism nor the etiology of this association has been fully explored or elucidated. Prior studies have detected myositis in patients with proven COVID-19 infection, suggesting a relationship between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the development of myositis. Studies have reported elevated levels of autoimmune antibodies, including myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs), in patients with COVID-19 infection, however the prevalence is not well documented. Our objective was to assess the prevalence of MSAs and MAAs in COVID-19 patients compared with unaffected subjects. Serum samples from 74 unvaccinated, polymerase chain reaction (PCR)-positive COVID-19 infected patients were compared with serum samples from 41 healthy, unaffected individuals. All serum samples were tested for MSA and MAA reactivity. Within the COVID-19-positive group, six (8.1%) patients exhibited MSA/MAA positivity, compared with only one (2.4%) individual from the control group. Although a higher prevalence of MSA/MAA positivity was observed within the COVID-19 infected group, the difference did not reach statistical significance (p=0.223). The autoantibodies detected in this study have a unique association with dermatomyositis and other inflammatory myopathies, and may play a role in COVID-19-associated myopathy. This article was previously presented as an abstract at Jacobs School of Medicine and Biomedical Sciences Research Day on June 3rd, 2022. 

Cancer and myositis: Who, when, and how to screen

Cancer screening in idiopathic inflammatory myopathies (IIMs) is essential because an increased risk of cancer in IIMs has been well demonstrated. However, a consensus regarding cancer screening approaches is lacking. Therefore, the approach presented in this review reflects available evidence and our clinical experiences. Patients with IIMs should be evaluated for 3 distinct types of risk categories: (a) clinical with their history, physical examination, and laboratory parameters; (b) based on IIMs subtypes; and (c) based on serology - myositis specific and associated autoantibodies. Further, according to these characteristics, patients should be classified as low risk, moderate risk, and high risk for cancer. In our approach, all patients with IIM within 3 years of disease onset should undertake cancer screening according to their risk stratification. First, irrespective of risk, all patients should undergo age and gender-appropriate screening as per local guidelines. Patients at low-risk stratification should undertake basic cancer screening with routine blood counts, labs, and imaging; at moderate-risk stratification, patients should undertake enhanced cancer screening including CT chest; and at high-risk stratification, patients should undertake comprehensive cancer screening including PET/CT at baseline. Consensus guidelines among all major stakeholders, including rheumatologists, neurologists, dermatologists, and oncologists representing different parts of the world, establishing uniform cancer screening approaches in patients with IIM, are the need of the hour.

Impact of dysphagia and its severity on long-term survival and swallowing function outcomes in patients with idiopathic inflammatory myopathies other than inclusion body myositis

OBJECTIVE

To investigate the impact of dysphagia on long-term survival and swallowing function outcomes in patients with idiopathic inflammatory myopathy other than inclusion body myositis.

METHODS

We retrospectively evaluated consecutive patients with idiopathic inflammatory myopathy other than inclusion body myositis to investigate the impact of dysphagia and its severity assessed using the Food Intake LEVEL Scale on survival and swallowing function outcomes. Time-to-event analyses were used, including Kaplan-Meier curves with log-rank (trend) test, cumulative incidence with Gray's test, and Cox proportional hazards models.

RESULTS

Of the 254 patients, 26 were dysphagic, including eight severe (Food Intake LEVEL Scale [FILS] score 2, 3) and six most severe (FILS score 1) cases; 210 were non-dysphagic, and 18 were indeterminate cases. During the 5 years after myositis diagnosis, 15 (57.7%) dysphagic and 31 (14.8%) non-dysphagic patients died, and dysphagic patients had significantly shorter survival. However, multivariate analysis showed that shorter survival was significantly associated with baseline age-adjusted Charlson Comorbidity Index (hazard ratio [HR] 1.57, 95% confidence interval [CI] 1.36-1.82]), but not with dysphagia (HR 1.46, 95% CI 0.69-3.10). Dysphagia severity was significantly associated with delayed recovery of dysphagia. In 20 non-severe or severe dysphagic cases, 19 restored swallowing function within 1 year. The most severe cases had a significantly higher cumulative probability of death before recovery from dysphagia than severe cases.

CONCLUSION

The poor survival of dysphagic myositis patients was largely confounded by advanced age and comorbid malignancies. However, patients with the most severe dysphagia had a significantly worse swallowing function and survival prognosis than those with milder dysphagia.

Aminoacyl-tRNA Synthetases: On Anti-Synthetase Syndrome and Beyond

Anti-synthetase syndrome (ASSD) is an autoimmune disease characterized by the presence of autoantibodies targeting one of several aminoacyl t-RNA synthetases (aaRSs) along with clinical features including interstitial lung disease, myositis, Raynaud’s phenomenon, arthritis, mechanic’s hands, and fever. The family of aaRSs consists of highly conserved cytoplasmic and mitochondrial enzymes, one for each amino acid, which are essential for the RNA translation machinery and protein synthesis. Along with their main functions, aaRSs are involved in the development of immune responses, regulation of transcription, and gene-specific silencing of translation. During the last decade, these proteins have been associated with cancer, neurological disorders, infectious responses, and autoimmune diseases including ASSD. To date, several aaRSs have been described to be possible autoantigens in different diseases. The most commonly described are histidyl (HisRS), threonyl (ThrRS), alanyl (AlaRS), glycyl (GlyRS), isoleucyl (IleRS), asparaginyl (AsnRS), phenylalanyl (PheRS), tyrosyl (TyrRS), lysyl (LysRS), glutaminyl (GlnRS), tryptophanyl (TrpRS), and seryl (SerRS) tRNA synthetases. Autoantibodies against the first eight autoantigens listed above have been associated with ASSD while the rest have been associated with other diseases. This review will address what is known about the function of the aaRSs with a focus on their autoantigenic properties. We will also describe the anti-aaRSs autoantibodies and their association to specific clinical manifestations, and discuss their potential contribution to the pathogenesis of ASSD.

[Dermatomyositis and juvenile dermatomyositis]

Dermatomyositis (DM) is an inflammatory multisystem disease of unknown etiology, which can already occur in children but first onset can also be in older adulthood. Myalgia and muscle weakness can occur later in the course of the disease or even be completely absent in some forms. Classical signs on the skin include heliotrope rash, facial erythema, Gottron's papules and nailfold capillary abnormalities. For the diagnosis, screening for the presence of myositis-specific autoantibodies has become increasingly more relevant. Muscle enzymes may be elevated but not in approximately one third of patients. In the absence of typical clinical or serologic findings, additional examination methods such as nailfold capillaroscopy, magnetic resonance imaging, electromyography, skin or muscle biopsies may help to establish the diagnosis. Depending on the clinical and serological subtype, additional screening for gastrointestinal or cardiopulmonary involvement should be considered. In adults, an age-appropriate tumor screening should also be performed. Apart from corticosteroids as induction therapy, biologics and small molecule inhibitors are gaining in importance in addition to conventional disease-modifying anti-rheumatic drugs and intravenous immunoglobulins. The prognosis for DM and juvenile DM (JDM) has improved. Most patients recover at least to some extent; however, a few patients die and a minority develop persisting muscle atrophy or severe calcinosis.

Using autoantibody signatures to define cancer risk in dermatomyositis

Dermatomyositis is an idiopathic inflammatory myopathy with a highly heterogeneous disease course. Although there is a known increase in cancer risk surrounding the time of dermatomyositis diagnosis, the mechanisms driving this increased risk are not well understood. Further, there are no current standardized cancer screening guidelines for dermatomyositis patients. In this issue of the JCI, Fiorentino, Mecoli, et al. discovered additional autoantibodies in patients with dermatomyositis and anti-TIF1-γ autoantibodies, a known risk factor for malignancy. They observed a decreased cancer risk with an increasing number of autoantibodies. Importantly, these findings indicate that more detailed autoantibody phenotyping at diagnosis might better predict cancer risk and also suggest that diversity and kinetics of the host immune response might influence cancer development.

Update on Malignancy in Myositis—Well-Established Association with Unmet Needs

Idiopathic inflammatory myopathies are a group of rare connective tissue diseases with a well-documented association with malignancy. The mechanisms underlying the increased risk of neoplasms in the course of myositis are not fully understood. The Pubmed database has been thoroughly screened for articles concerning cancer-associated myositis (CAM). The article summarizes the current state of knowledge on the epidemiology and pathogenesis of CAM. Furthermore, it analyses potential risk and protective factors for developing CAM, with particular emphasis on the association with distinct serological profiles. The review summarizes recommendations proposed so far for the management of CAM and presents a novel scheme for cancer screening proposed by the authors. Moreover, promising areas requiring further research were indicated.

Autoantibody Markers of Increased Risk of Malignancy in Patients with Dermatomyositis

Dermatomyositis is a chronic inflammatory disease involving the skin and muscles. It most commonly occurs in adults with preponderance in females, but pediatric occurrence is also possible. The risk of malignancy in adult patients with dermatomyositis was reported to be 4.66-fold higher compared to that in the general population. A significantly increased risk of malignancy was reported within the first 12 months following the diagnosis of dermatomyositis (standardized incidence ratio equaled 17). One of the characteristic laboratory findings associated with dermatomyositis is the presence of circulating autoantibodies which are classified into two subgroups: myositis-specific and myositis-associated autoantibodies. It was shown that specific types of antibodies might be associated with an increased risk of malignancy. Current literature data indicate that the strongest correlation with malignant diseases was reported in anti-TIF1-γ-positive patients who were at a 9.37-fold higher risk of cancer. A 3.68-fold increase in the risk of cancer was also reported among patients with anti-NXP2 antibodies. Malignant diseases were reported in 14-57% of patients with anti-SAE antibodies. The presence of other autoantibodies may also be associated with an increased risk of malignancy. These data indicate that patients with circulating anti-TIF1-γ, anti-NXP2, and anti-SAE should be very closely monitored for dermatomyositis-associated malignant comorbidities. The aim of this review is to summarize the current data regarding the link between malignancy and the presence of specific antibodies in patients with dermatomyositis.

Cancer screening in idiopathic inflammatory myopathies: Ten years experience from a single center

OBJECTIVE

There is a well-recognized association between cancer and myositis, so cancer screening at diagnosis is recommended. We aim to report the results of our cancer screening strategy and to ascertain the reliability of using PET/CT to identify cancer-associated myositis (CAM) in a large cohort of patients with myositis from a single center over 10 years.

METHODS

This retrospective observational study included all patients diagnosed with any type of myositis except for inclusion body myositis. Cancer screening strategy was individualized according to clinical and serological data, including PET/CT as the main test to detect occult cancer (OC). Procedures derived from a positive PET/CT were registered. Qualitative data expressed as percentages, and quantitative data as the median with the interquartile range were analyzed. A ROC curve was used to estimate the reliability of PET/CT for CAM diagnosis.

RESULTS

Seventy-seven out of 131 patients underwent a PET/CT for OC screening. The performance of the PET/CT in patients with myositis at disease onset yielded an area under the curve ROC of 0.87 (0.73-0.97) for CAM diagnosis. Invasive procedures in 7 (9%) patients without a final diagnosis of cancer did not cause derived complications. Patients not evaluated for OC did not develop cancer after a median follow-up of 3.3 years (1.7-6.7).

CONCLUSION

Cancer screening strategy should be individualized. PET/CT at myositis onset seems to be an efficient approach to rule out CAM. This practice does not seem to significantly increase harm to patients related to the additional tests needed to clarify inconclusive results.

Diagnostic Dilemma of Paraneoplastic Rheumatic Disorders: Case Series and Narrative Review

Paraneoplastic rheumatic disorder (RD) is a disorder that may present before, concurrent with, or after the diagnosis of malignancy. Paraneoplastic RDs are a clinical expression of occult cancer that is not directly related to a tumor or metastasis and manifests as rheumatoid symptoms. The RD is determined by the organ system affected by articular, muscular, cutaneous, vascular, or miscellaneous symptoms. Each case is challenging to diagnose because cancer may present with similar symptoms as a common rheumatic disorder. Of note, the majority of cases have minimal responsiveness or no responsiveness to standard rheumatoid treatment. Therefore, it is imperative to recognize and treat the underlying cancer accordingly. Herein, we present four different diagnostic dilemma cases of RD: case #1 - leukocytoclastic vasculitis and C3 glomerulopathy, case #2 - scleroderma, case #3 - Raynaud’s syndrome and possible lupus-like syndrome, and case #4 - inflammatory myositis. Institutional IRB approval was obtained for this case series. We will discuss and review the literature on each topic. In addition, we will mention a review of paraneoplastic rheumatoid arthritis. As rheumatic disease is associated with the use of immune checkpoint inhibitors (ICIs) for cancer treatment, we will briefly discuss some of the most common rheumatic presentations in the setting of these drugs. This case review aims to inform clinicians about the atypical presentation of paraneoplastic RD and to highlight the need for interdisciplinary management between rheumatologists, oncologists, and primary care practitioners.

Clinical and laboratory parameters predicting cancer in dermatomyositis patients with anti-TIF1γ antibodies

BACKGROUND

Dermatomyositis (DM) is a chronic acquired autoimmune disorder strongly associated with cancer development. Until now, identifying predictive markers indicating a high risk of cancer has challenged clinicians. Although anti-TIF1γ antibody is a major serological indicator for cancer-associated DM, many anti-TIF1γ antibody-positive DM patients lack malignancy.

OBJECTIVES

To determine clinical and laboratory parameters that support cancer prediction in anti-TIF1γ antibody-positive DM patients.

METHODS

Clinical and laboratory data were collected from cancer-associated and unassociated DM patients with anti-TIF1γ antibodies. Serum cytokine concentrations were measured with a cytokine array assay. The values of inflammatory cytokines in cancer prognosis were determined with a receiver operating characteristic curve analysis.

RESULTS

The cancer group had a significantly higher frequency of males, older mean age and higher anti-TIF1γ antibody levels. Some inflammatory cytokines, particularly tumour necrosis factor (TNF) and TNF receptor superfamilies, had increased levels in sera that were correlated with myositis markers, cutaneous severity and DM disease activity. Moreover, these cytokines had an area under the curve (AUC) ≥0.8 and high sensitivity and specificity at their specific cut-off, even higher than anti-TIF1γ levels in cancer prediction in our DM patients.

CONCLUSIONS

Our results suggest a close pathophysiological relationship among myositis, cancer and skin involvements in DM patients with anti-TIF1γ antibodies and the potential clinical significance of anti-TIF1γ antibody levels in evaluating disease severity and prognosis in DM patients. Some inflammatory cytokines, particularly TNF and TNF receptor superfamilies including BAFF, sTNF-R1 and sTNF-R2, may support cancer prediction in DM patients with anti-TIF1γ antibodies.

A systematic review and meta-analysis to inform cancer screening guidelines in idiopathic inflammatory myopathies

Objectives

To identify clinical factors associated with cancer risk in the idiopathic inflammatory myopathies (IIMs) and to systematically review the existing evidence related to cancer screening.

Methods

A systematic literature search was carried out on Medline, Embase and Scopus. Cancer risk within the IIM population (i.e. not compared with the general population) was expressed as risk ratios (RR) for binary variables and weighted mean differences (WMD) for continuous variables. Evidence relating to cancer screening practices in the IIMs were synthesized via narrative review.

Results

Sixty-nine studies were included in the meta-analysis. DM subtype (RR 2.21), older age (WMD 11.19), male sex (RR 1.53), dysphagia (RR 2.09), cutaneous ulceration (RR 2.73) and anti-transcriptional intermediary factor-1 gamma positivity (RR 4.66) were identified as being associated with significantly increased risk of cancer. PM (RR 0.49) and clinically amyopathic DM (RR 0.44) subtypes, Raynaud’s phenomenon (RR 0.61), interstitial lung disease (RR 0.49), very high serum creatine kinase (WMD −1189.96) or lactate dehydrogenase (WMD −336.52) levels, and anti-Jo1 (RR 0.45) or anti-EJ (RR 0.17) positivity were identified as being associated with significantly reduced risk of cancer. Nine studies relating to IIM-specific cancer screening were included. CT scanning of the thorax, abdomen and pelvis appeared to be effective in identifying underlying asymptomatic cancers.

Conclusion

Cancer risk factors should be evaluated in patients with IIM for risk stratification. Screening evidence is limited but CT scanning could be useful. Prospective studies and consensus guidelines are needed to establish cancer screening strategies in IIM patients.

NanoString technology distinguishes anti-TIF-1γ+ from anti-Mi-2+ dermatomyositis patients

Dermatomyositis (DM) is a systemic idiopathic inflammatory disease affecting skeletal muscle and skin, clinically characterized by symmetrical proximal muscle weakness and typical skin lesions. Recently, myositis-specific autoantibodies (MSA) became of utmost importance because they strongly correlate with distinct clinical manifestations and prognosis. Antibodies against transcription intermediary factor 1γ (TIF-1γ) are frequently associated with increased risk of malignancy, a specific cutaneous phenotype and limited response to therapy in adult DM patients. Anti-Mi-2 autoantibodies, in contrast, are typically associated with classic DM rashes, prominent skeletal muscle weakness, better therapeutic response and prognosis, and less frequently with cancer. Nevertheless, the sensitivity of autoantibody testing is only moderate, and alternative reliable methods for DM patient stratification and prediction of cancer risk are needed. To further investigate these clinically distinct DM subgroups, we herein analyzed 30 DM patients (n = 15 Mi-2⁺ and n = 15 TIF-1 γ⁺ ) and n = 8 non-disease controls (NDC). We demonstrate that the NanoString technology can be used as a very sensitive method to clearly differentiate these two clinically distinct DM subgroups. Using the nCounter PanCancer Immune Profiling Panel™, we identified a set of significantly dysregulated genes in anti-TIF-1γ⁺ patient muscle biopsies including VEGFA, DDX58, IFNB1, CCL5, IL12RB2, and CD84. Investigation of type I IFN-regulated transcripts revealed a striking type I interferon signature in anti-Mi-2⁺ patient biopsies. Our results help to stratify both subgroups and predict, which DM patients require an intensified diagnostic procedure and might have a poorer outcome. Potentially, this could also have implications for the therapeutic approach.

Jackhammer Esophagus: Current Concepts and Dilemmas

Jackhammer esophagus (JE) is a recently recognized esophageal motility disorder that is characterized by hypercontractile peristalsis. More than 500 cases have been reported in the literature. Among patients referred for esophageal motility disorders, the prevalence of JE ranges from 0.42% to 9%, with most series describing a prevalence of 2% to 4%. Most cases are women (60.5%). The mean reported age of patients with JE is 65.2 years, and patients commonly have dysphagia (62.8%). Reflux symptoms occur in ∼40% of patients, and chest pain affects more than one-third of patients (36.4%). JE is a heterogenous disorder that is associated with several conditions, including obesity, opioid use, lung transplantation, eosinophilic infiltration of the esophagus, neoplasia, and systemic diseases. The cause and pathogenesis remain unknown, but several observations suggest that it is the result of multiple conditions that likely precipitate increased excitation and abnormal inhibition of neuromuscular function. The natural course of JE also is unknown, but progression to achalasia has been observed in a few patients. Treatment is challenging, in part because of the insufficient understanding of the disorder's underlying mechanisms. Various therapeutic modalities have been used, ranging from observation only to pharmacologic and endoscopic interventions (eg, botulinum toxin injection) to peroral endoscopic myotomy. Treatment efficacy remains largely anecdotal and insufficiently studied.

Dermatomyositis and malignancy: should all patients with dermatomyositis undergo malignancy screening?

Dermatomyositis is an autoimmune disease that occurs in association with underlying malignancy in a subset of patients. Given this association, diagnosis of dermatomyositis typically triggers malignancy screening. Although various malignancy screening protocols have been proposed, none have been extensively studied or taken into account prevalence of dermatomyositis-associated malignancies. We utilized peer-reviewed manuscripts identified by a Medline search from May 2000 to April 2020 to present a focused review concerning the association between dermatomyositis and malignancy, and controversies related to screening for malignancies most commonly occurring in dermatomyositis patients. This information was then synthesized to propose a rational strategy for approaching malignancy screening in dermatomyositis patients. Our review supports that risk of malignancy in dermatomyositis patients is well-established. However, the subset of dermatomyositis patients in whom the benefits of malignancy screening outweigh the risks of harm is unknown. Additionally, an evidence-based malignancy screening protocol for dermatomyositis patients that optimizes the risk:benefit ratio does not exist. Given the clear harms that can result, we propose that shared decision-making strategies be implemented to determine whether pursuit of malignancy screening conforms with dermatomyositis patients’ desires and values. Physicians should be clear about potential risks and benefits of malignancy screening, and discuss clinical and serologic features present that may suggest/refute underlying malignancy during conversations aimed at shared decision-making. Research is greatly needed to determine which dermatomyositis patients warrant malignancy screening, which tests should be performed, and the intensity with which they should be ordered. Only after such work is done can malignancy screening in dermatomyositis patients be considered to have high value.

The clinical phenotype of Systemic Sclerosis patients with anti-PM/Scl antibodies: results from the EUSTAR cohort

OBJECTIVE

To evaluate clinical associations of anti-PM/Scl antibodies in patients with Systemic Sclerosis (SSc) in a multicentre international cohort, with particular focus on unresolved issues, including scleroderma renal crisis (SRC), malignancies, and functional outcome of interstitial lung disease (ILD).

METHODS

(1) Analysis of SSc patients from the EUSTAR database: 144 anti-PM/Scl+ without SSc-specific autoantibodies were compared to 7,202 anti-PM/Scl-, and then to 155 anti-Pm/Scl+ with SSc-specific antibodies. (2) Case-control study: additional data were collected for 165 anti-PM/Scl+ SSc (85 from the EUSTAR registry), and compared to 257 anti-PM/Scl- SSc controls, matched for sex, cutaneous subset, disease duration, and age at SSc onset.

RESULTS

Patients with isolated anti-PM/Scl positivity, as compared with anti-Pm/Scl-, had higher frequency of muscle involvement, ILD, calcinosis and cutaneous signs of dermatomyositis, but similar frequency of SRC and malignancies (either synchronous with SSc onset or not). The presence of muscle involvement was associated with a more severe disease phenotype. Although very frequent, ILD had a better functional outcome in cases than in controls.In patients with both anti-PM/Scl and SSc-specific antibodies, a higher frequency of typical SSc features than in those with isolated anti-PM/Scl was observed.

CONCLUSION

The analysis of the largest series of anti-PM/Scl+ SSc patients so far reported helps to delineate a specific clinical subset with muscle involvement, cutaneous dermatomyositis, calcinosis, and ILD characterized by a good functional outcome. SRC and malignancies do not seem to be part of this syndrome.

Risk factors for cancer-associated myositis: A large-scale multicenter cohort study

AIM

The aim of this study was to identify the risk factors and prognosis of patients with cancer-associated myositis (CAM).

METHOD

Four hundred and eighty-seven patients with dermatomyositis (DM), clinical amyopathic dermatomyositis (CADM) and polymyositis (PM) from 3 clinical centers were enrolled retrospectively in this study. Clinical and laboratory data of CAM and non-CAM patients were compared. Logistic regression analysis was used to identify risk factors of CAM.

RESULTS

Out of the 487 patients with DM/CADM/PM, 7.0% (34/487) of patients were classified as CAM. Older age (53.91 ± 13.32 vs. 48.76 ± 14.34 years), heliotrope rash (61.8% vs. 41.9%), shawl sign (41.2% vs. 22.1%), V sign (58.8% vs. 38.6%) were observed significantly more commonly in patients with CAM than those without CAM (all P < .05). Fever (17.7% vs. 37.8%), arthralgia/arthritis (23.5% vs. 45.7%), interstitial lung disease (ILD, 38.2% vs 68.9%) were significantly less common in the CAM group than the non-CAM group. Age at onset (odds ratio [OR] 1.036, 95% CI 1.001-1.072, P = .042), shawl sign (OR 2.748, 95% CI 1.107-6.822, P = .029), anti-transition initiation factor (TIF)-1γ antibody (OR 4.012, 95% CI 1.268-12.687, P = .018) were identified as the initial risk factors for the onset of CAM, and ILD was identified as a protective factor for CAM (OR 0.292, 95% CI 0.115-0.739, P = .009). All-cause mortality was significantly higher in CAM patients compared with non-CAM patients (P = .001).

CONCLUSION

The mortality of patients with CAM was higher than DM/CADM/PM patients without cancer. Malignancy should be screened in DM/CADM/PM patients especially with risk factors, including older age, shawl sign, anti-TIF-1γ antibody, and lack of ILD.

Monitoring disease activity and damage in adult and juvenile idiopathic inflammatory myopathy

PURPOSE OF REVIEW

We have reviewed the literature to identify significant advances related to disease activity and damage in the idiopathic inflammatory myopathies (IIMs) from January 2019 to July 2020.

RECENT FINDINGS

New observations in the field from 2019 to 2020 have resulted in a better understanding of the clinical association and pathogenic origins of IIM. The use of patient-reported outcome measures and perspectives, identifying biomarkers and making better use of autoantibody testing are summarized. Basic sciences have led to an improved understanding of the role of NETosis in calcinosis, and of interferon type 1, in IIM. Preliminary insights are offered into Covid-19 in the setting of IIM, and the use of potential tools for monitoring disease remotely, which may assume larger importance for optimal disease management during a global pandemic. The wider exploration of newer imaging modalities and the use of nailfold capillaroscopy is a further step in better management of the condition.

SUMMARY

The summarized research in IIM is a step forward in being able to further define, and to distinguish disease activity from damage, in order to potentially aid future clinical diagnosis and management in this challenging disease.

Paraneoplastic dermatomyositis associated with metastatic leiomyosarcoma of unknown primary

Background

Sarcomas are rare and heterogeneous tumours of mesenchymal origin, with over 100 histological subtypes. Paraneoplastic dermatomyositis has rarely been described in sarcoma. This is the first documented case of paraneoplastic dermatomyositis in a patient with metastatic leiomyosarcoma.

Case presentation

A 43-year-old female diagnosed with metastatic leiomyosarcoma of unknown primary presented with a mild rash in sun-exposed areas of her face and upper chest, with no other neuromuscular symptoms. This rash resolved with systemic treatment with doxorubicin for metastatic leiomyosarcoma. Imaging assessment confirmed overall stable disease after chemotherapy completion. She presented acutely 2 months later with new onset rash in a shawl-like distribution, periorbital oedema and proximal muscle weakness. Based on the characteristic cutaneous signs and symmetrical proximal muscle weakness, abnormal electromyography and raised skeletal muscle enzymes with a positive anti-transcription intermediary factor-1 gamma antibody result, a diagnosis of paraneoplastic dermatomyositis was made. Re-evaluation of her metastatic leiomyosarcoma revealed disease progression. Second-line chemotherapy was commenced once the dermatomyositis was controlled on steroid therapy. Systemic anti-cancer therapy was again associated with mild improvement in dermatomyositis symptoms.

Discussion

Paraneoplastic dermatomyositis heralded disease progression after first-line chemotherapy; however, in hindsight, subtle cutaneous features were present at sarcoma diagnosis. The temporal relationship between paraneoplastic dermatomyositis and metastatic leiomyosarcoma is key in this case, as fluctuations in dermatomyositis severity correlated with growth of metastatic disease. Understanding this relationship may provide clues for tumour progression and prompt timely initiation of anti-cancer therapy. It is important to recognise that in addition to the more common cancers associated with paraneoplastic dermatomyositis, it can also occur in rarer tumours such as leiomyosarcoma.

Clinical characteristics and prognostic analysis of Chinese dermatomyositis patients with malignancies

Although a strong association between idiopathic inflammatory myositis (IIM) and malignancy has been widely reported, few studies have solely focused on the concurrence of dermatomyositis (DM) and malignancies (DM-malignancy).We conducted a retrospective analysis of 37 DM-malignancy cases among 363 DM patients admitted to our hospital between January 2012 and December 2017.(1) The mean age at DM diagnosis was higher for DM-malignancy patients than for DM-non-malignancy patients [(54.76 ± 9.77) years vs (48.57 ± 12.82) years, t = 2.84, P = .005]. (2) Gynecological malignancies (35.90%/14 cases) were the most common malignancies. Malignancies were diagnosed before DM for 7 DM-malignancy patients. The interval between the DM and malignancy diagnoses for the remaining 32 DM-malignancy patients was less than 6 months for 18 patients (46.15%), less than 1 years for 23 patients (58.9%), and less than 2 years for 29 patients (74.26%). (3) There was no significant difference either in antinuclear antibody or anti-Ro-52 positivity between the 2 groups (P > .05). (4) Multivariate analysis demonstrated that DM onset age ≥50 years and concurrence with ILD increased the risk of death for DM patients [hazard ratio (HR): 1.62 and 2.72; 95% confidence interval (CI): (1.08-2.43) and (1.47-5.02); P = .02 and 0.001, respectively], and male gender decreased the risk of death [HR 0.66, 95% CI (0.44-0.98), P = .04]. DM-malignancy patients were older than DM-non-malignancy patients. Gynecological malignancies were the most common malignancies among these patients. A DM onset age ≥50 years, female sex and the presence of ILD were independent risk factors for death.

Anti-EJ Antibody-positive Anti-synthetase Syndrome Associated with Retroperitoneal Sarcoma

A 74-year-old man with interstitial lung disease (ILD) underwent surgical excision of a growing retroperitoneal tumor and was diagnosed with spindle cell sarcoma. Just after the surgery, skin eruption and muscle weakness emerged. Based on his symptoms and examination findings, we diagnosed him with anti-synthetase syndrome (ASS) with positive anti-glycyl-transfer ribonucleic acid synthetase antibody (anti-EJ) as paraneoplastic syndrome. Immunosuppressive treatments kept his progressing ILD stable for 21 months, although an expanding lung metastatic lesion from primary sarcoma was detected. Measurements of myositis-specific antibodies may enable the prediction of the efficacy of immunosuppressive treatments for paraneoplastic syndrome, even if the primary disease becomes progressive.

Clinical features of anti-transcription intermediary factor 1γ (TIF1γ)-positive dermatomyositis with internal malignancy and investigation of the involvement of TIF1γ expression in tumors in the pathogenesis of cancer-associated dermatomyositis

Anti-transcription intermediary factor 1γ (anti-TIF1γ) antibody (Ab) is significantly associated with internal malignancies in adult patients with dermatomyositis (DM). Although pathogenesis of cancer-associated DM is unknown, TIF1γ overexpression in tumors has been considered to be critical for the development of DM. The objective of this study was to investigate clinical characteristics of patients with anti-TIF1γ Ab-positive DM and elucidate risk factors that are potentially associated with internal malignancy. In addition, we compared the expression of TIF1γ in tumor tissues of patients with anti-TIF1γ Ab-positive DM, anti-TIF1γ Ab-negative DM and without DM in order to investigate the pathogenesis of cancer-associated DM. We analyzed 77 Japanese patients with DM, and found 19 patients to be positive for anti-TIF1γ Ab. Patients with anti-TIF1γ Ab-positive DM were older and presented heliotrope rash and flagellate erythema more frequently than patients without anti-TIF1γ Ab (P < 0.05). Interstitial lung disease (ILD) and rapidly progressive ILD, as well as palmar violaceous erythema, were less frequent in patients with anti-TIF1γ Ab than in patients without. Furthermore, internal malignancy and dysphagia were significantly more frequent in the anti-TIF1γ Ab-positive group (P < 0.01). Male sex and dysphagia were significantly associated with internal malignancy in patients with anti-TIF1γ Ab-positive DM (P < 0.01 and <0.05, respectively). Using immunohistochemistry, we examined the TIF1γ expression in tumors of 11 patients with cancer-associated DM (anti-TIF1γ Ab-positive, nine; anti-TIF1γ Ab-negative, two) and 25 patients without DM. TIF1γ was highly expressed in all tumors, and there was no significant difference in TIF1γ expression between patients with and without DM. Furthermore, TIF1γ expressions in tumors were similar irrespective of the presence of anti-TIF1γ Ab. These results suggest that anti-TIF1γ antibody may not be simply induced by overexpression of TIF1γ in tumors in patients with DM, but that other mechanisms may exist.

Malignancy in dermatomyositis: A retrospective study of 201 patients seen at the University of Pennsylvania

BACKGROUND

There is an increased incidence of malignancy in patients with dermatomyositis. It is unknown if the risk differs between the subtypes of dermatomyositis.

OBJECTIVE

To (1) compare the prevalence of malignancy-associated dermatomyositis between patients with classic and clinically amyopathic disease and (2) determine factors associated with an increased risk of malignancy-associated disease.

METHODS

Retrospective cohort study of 201 patients with adult-onset dermatomyositis prospectively enrolled in a longitudinal dermatomyositis database between July 2008 and April 2018 at an outpatient dermatology urban tertiary referral center. The main outcome measure was a diagnosis of malignancy, excluding nonmelanoma skin cancer.

RESULTS

There were 201 patients with adult-onset dermatomyositis: 142 (71%) classic and 59 (29%) clinically amyopathic. Within 2 years of diagnosis, the prevalences of malignancy-associated classic and clinically amyopathic dermatomyositis were 9.9% and 1.7%, respectively. In this time period, patients who were older at dermatomyositis diagnosis (P = .01) and had the classic subtype (P = .04) were significantly more likely to have an underlying malignancy on multivariable regression analysis.

LIMITATIONS

This was a retrospective study of prospectively collected data at a single tertiary referral center.

CONCLUSION

Older age and classic dermatomyositis are independent risk factors for malignancy-associated dermatomyositis within 2 years of disease onset.

What is New in Idiopathic Inflammatory Myopathies: Mechanisms and Therapies

Idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of disorders that cause muscle weakness and also have extramuscular manifestations involving various organ systems; namely the lung, skin, heart, and joints. Previously classified broadly as dermatomyositis (DM) and polymyositis now the spectrum of the disease has evolved into more clinical subtypes. There are now five clinicoserological subtypes recognized worldwide DM, antisynthetase syndrome (AS), overlap myositis (OM), immune mediated necrotizing myopathy (IMNM), and inclusion body myositis. Each of these subtypes has a unique phenotype and specific antibodies associated. With the evolving treatment options from the use of immunosuppressive medications to the use of targeted therapy with biologic agents, and further understanding of the pathogenesis of inflammatory myositis, we may have more effective treatment options. We discuss in this review, various myositis-associated antibodies associated with each clinicoserological subtype of IIM and their role. We also describe the evolving therapies and the evidence for the newer biologic therapies in the treatment of IIMs.

Predictive factors for sustained remission with stratification by myositis-specific autoantibodies in adult polymyositis/dermatomyositis

OBJECTIVE

The aim of this study was to clarify predictive factors for sustained remission in adult patients with PM/DM, particularly focusing on stratification by myositis-specific autoantibodies (MSAs).

METHODS

A total of 162 adult patients with PM/DM who were followed up for >1 year after diagnosis were retrospectively enrolled. MSAs were evaluated comprehensively in 102 patients whose sera were available. Sustained remission was defined as no evidence of disease activity (active skin rash, active myositis or active interstitial lung disease) for longer than a 6-month continuous period while undergoing myositis therapy or no medication. Clinical data were reviewed in patients' medical charts.

RESULTS

The sustained remission rate for all patients was 58% during the median follow-up period at 4 years. With regard to MSAs, the achievement rate of sustained remission among MSA-negative patients was significantly higher than that for patients with anti-aminoacyl-tRNA synthetase (P = 0.004), anti-melanoma differentiation-associated gene 5 (P = 0.037) or anti-transcriptional intermediary factor 1-γ (P = 0.013) antibodies. MSA-negative status (odds ratio 5.84, P = 0.009) and absence of severe muscle weakness requiring assistance at diagnosis (odds ratio 43.6, P < 0.001) were independent factors associated with sustained remission in multivariate analysis. Cumulative remission rates were significantly higher (P < 0.001) in patients with both the MSA-negative status and absence of severe muscle weakness at diagnosis than the others.

CONCLUSION

MSA-negative status and the absence of severe muscle weakness requiring assistance at diagnosis are independent predictive factors for sustained remission in adult PM/DM patients.

Anti-TIF1-γ autoantibodies: warning lights of a tumour autoantigen

Anti-transcription intermediary factor 1 (TIF1)-γ autoantibodies are robustly linked with cancer-associated DM in adults. This review aims to give an overview of the physiological context of TIF1-γ and to determine whether there is a pathophysiological link between anti-TIF1-γ autoantibodies and the occurrence of cancer. Detection of anti-TIF1-γ autoantibodies has a high sensitivity and specificity for cancer-associated DM in adults and is therefore useful for both diagnosis and cancer risk stratification. The function of the autoantigen, TIF1-γ, may provide insight into the mechanism behind this association. TIF1-γ is a ubiquitously present protein involved in various biological pathways, including TGF-β signalling. In cancer, it can act either as a tumour suppressor or promoter, depending on the cellular context and cancer stage. Evolving data provide pathophysiological insights, linking anti-TIF1-γ autoantibodies to both the anti-tumour response and to muscle and skin damage. TIF1-γ expression is increased in muscle and skin tissue of patients with DM. Mutations or loss-of-heterozygosity in TIF1-γ alleles in malignant tissue may result in the expression of tumour-specific neo-antigens stimulating autoantibody production. The newly formed autoantibodies are hypothesized to cross-react with antigens in muscle and skin, driving the development of DM. Based on the current evidence, anti-TIF1-γ autoantibodies should be considered warning lights of a potential tumour autoantigen and should alert the physician to the possibility of an underlying cancer.

Cutaneous manifestations of internal malignancy

Skin lesions associated with internal malignancy may present as cutaneous metastases or as typical lesions occurring in the context of certain cancer-associated genetic syndromes. Paraneoplastic syndromes, on the other hand, are only indirectly associated with an underlying malignancy and are not malignant per se. Historically, a distinction has been made between "obligate" and "facultative" paraneoplastic disorders, depending on the likelihood with which they are potentially associated with malignancy. In addition, there are nonspecific cutaneous manifestations that are only rarely associated with an underlying malignancy. Another possible classification is based on the pathophysiological mechanisms underlying the cutaneous lesions. In everyday practice, it is essential that dermatologists recognize potentially cancer-associated dermatoses, as this will frequently contribute to the initial diagnosis of an underlying neoplasm.

Analysis of myositis autoantibodies in Chinese patients with cancer-associated myositis

Background

Cancer‐associated myositis (CAM) has poor prognosis and causes higher mortality. In general, myositis‐specific autoantibodies (MSAs) and myositis‐associated autoantibodies (MAAs) have been shown to be useful biomarkers for its diagnosis.

Methods

In the present study, focus was given in assessing the presence, prevalence, and diagnostic values of myositis autoantibodies in Chinese patients diagnosed with CAM. The sera collected from 49 CAM patients, 108 dermatomyositis/polymyositis (DM/PM) patients without cancer, 105 disease controls, and 60 healthy controls were detected for the presence of 16 autoantigens (Jo‐1, OJ, EJ, PL‐7, PL‐12, MDA5, TIF1γ, Mi‐2α, Mi‐2β, SAE1, NXP2, SRP, Ku, PM‐Scl75, PM‐Scl100, and Ro‐52) using a commercial Euroline assay.

Results

The frequency of anti‐TIF1γ was significantly higher in CAM patients than in DM/PM patients without cancer (46.9% vs 14.8%, P < .001). Importantly, the sensitivity and specificity for this MSA were 46.9% and 85.2%, respectively. These helped to differentiate CAM patients from DM/PM patients without cancer. However, there was no difference in other MSAs and MAAs between CAM and DM/PM patients without cancer.

Conclusion

The present study indicates that anti‐TIF1γ levels can serve as important biomarkers for CAM diagnosis and help in distinguishing between CAM and DM/PM patients without cancer.