Carbohydrate antigen 15.3 as a serum biomarker of interstitial lung disease in systemic sclerosis patients

Serum carbohydrate antigen 153 as a predictor of interstitial lung disease associated with rheumatoid arthritis is positively correlated with serum Krebs von den Lungen-6

OBJECTIVE

The objective of this study was to evaluate the clinical significance of carbohydrate antigen (CA) 153 and its correlation with Krebs von den Lungen-6 (KL-6) in the prediction and determination of the severity of interstitial lung disease (ILD) in rheumatoid arthritis (RA) patients.

METHODS

Data was collected retrospectively on a cohort of 357 RA patients who were admitted to our hospital from January 2018 to December 2020. The classification of patients into subgroups was based on high-resolution computed tomography (HRCT) of the chest, resulting in 135 patients with RA but no ILD, 107 patients with RA and indeterminate ILD, 91 patients with RA and mild ILD, and 24 patients with RA and advanced ILD. The levels of CA153 and KL-6 were determined by chemiluminescence analysis.

RESULTS

The serum levels of CA153 were found to be significantly higher in both the RA-mild ILD group and the RA-advanced ILD group compared to the RA-no ILD group (8.00 vs. 6.40, q = 0.039; 20.30 vs. 6.40, q < 0.001). Multivariate analysis demonstrated that CA153 was an independent risk factor for RA-ILD (RA-mild ILD + RA-advanced ILD) [odds ratio (OR) = 1.124, 95% confidence interval (CI) = (1.060-1.191), p < 0.001] and RA-advanced ILD (OR = 1.583, 95% CI = 1.247-2.010, p < 0.001). Furthermore, the receiver operating characteristic (ROC) analysis indicated that CA153 had diagnostic value for both RA-ILD (RA-mild ILD + RA-advanced ILD) and RA-advanced ILD. The best area under ROC curve (AUC) of CA153 for RA-ILD (RA-mild ILD + RA-advanced ILD) was 0.66 (p < 0.001; sensitivity = 57.27%; specificity = 72.03%). The AUC of CA153 for RA-advanced ILD was 0.95 (p < 0.001; sensitivity = 95.65%; specificity = 83.05%). Moreover, CA153 was negatively correlated with forced vital capacity percent predicted (FVC% pred) (r = -0.383, p = 0.037) but positively related to KL-6 (r = 0.762, p < 0.001).

CONCLUSION

It was concluded that CA153 was positively associated with KL-6 and might be a significant and clinical availably measurable serum marker to predict the diagnosis and severity of ILD in RA patients.

CA 15 - 3 in screening for systemic autoimmune rheumatic disease associated interstitial lung disease: a single center cross-sectional study

INTRODUCTION

The natural course of interstitial lung disease (ILD) in patients with systemic autoimmune rheumatic diseases (SARD) varies significantly and is linked to considerable morbidity and mortality. Therefore, effective screening is crucial for early detection of SARD-ILD. Biomarkers associated with mucin 1, Krebs von den Lungen-6 (KL-6) and carbohydrate antigen 15-3 (CA 15-3), are increased in various ILD. This study aimed to assess the diagnostic accuracy of the serum biomarker CA 15-3 as a potential screening tool for ILD in patients newly diagnosed with SARD.

METHODS

Conducted as a single-center cross-sectional study, the research included newly diagnosed SARD patients consecutively examined for ILD according to the algorithm. All included patients underwent chest high-resolution CT scans (HRCT), and serum levels of CA 15-3, KL-6, and lactate dehydrogenase (LDH) were measured and correlated with other variables associated with possible ILD presence.

RESULTS

Serum biomarker levels, specifically CA 15-3 and LDH, are significantly higher in ILD-positive patients (P<0.001 for both). An inverse relationship is observed between higher FVC values and lower CA 15-3 levels (Rho=-0.291, P=0.007). Similarly, higher DLCO values are associated with lower CA 15-3 levels (Rho=-0.317, P=0.003). Our findings revealed that elevated CA 15-3 levels are positively correlated with higher levels of KL-6 (Rho=0.268, P=0.01) and LDH (Rho=0.227, P=0.04). With a cut-off value of 24 U/mL, CA 15-3 showed the highest sensitivity and specificity (AUC=0.807, specificity=95.7%, sensitivity=71.1%). CA 15-3 emerged as the most significant predictor of a positive HRCT finding, accurately classifying 83% of cases.

CONCLUSION

These results suggest that CA 15-3 shows promise as a valuable serum biomarker for screening SARD patients for ILD in routine clinical practice.

Hypermetabolic Pulmonary and Mediastinal Lesions With Elevated Cancer Antigen (CA) 15-3 and CA 27-29 in a Patient With a History of Ovarian and Breast Cancer

Breast cancer affects around 13% of women. Breast cancer gene 1 (BRCA1) carriers are prone to lung and lymph node metastasis, while breast cancer gene 2 (BRCA2) carriers tend to have bone metastasis. Findings of pulmonary nodules, mediastinal lymphadenopathy, and elevated markers such as cancer antigen (CA) 15-3 and CA 27-29 suggest metastatic disease. Here, we present the case of a patient with BRCA1-positive breast cancer in remission and a history of ovarian cancer with mediastinal lymphadenopathy and pulmonary nodules, with avid fluorodeoxyglucose uptake on positron emission tomography (PET) scan and elevated CA 15-3 and CA 27-29. A 70-year-old female with a history of bilateral breast and ovarian cancer and a positive BRCA test presented with pulmonary nodules, mediastinal lymphadenopathy, and elevated CA 15-3 and CA 27-29. Imaging showed mediastinal and hilar lymphadenopathy. A PET scan revealed increased metabolic activity in the lymph nodes and pulmonary lesions. Fiberoptic bronchoscopy and endobronchial ultrasound lymph node sampling demonstrated granulomatous inflammation without malignant cells. The patient underwent a therapeutic trial of steroids with clinical improvement of symptoms and decreased hypermetabolic activity in chest lesions, as well as a decrease in tumor markers. The coexistence of sarcoidosis and breast cancer is rare; sarcoidosis can coexist, precede, or appear after breast cancer. In both conditions, tumor markers and PET avidity are seen, which makes diagnosis and management challenging. In case of ambiguity, biopsy is crucial. This case underscores the importance of integrating clinical, pathological, and imaging data to reach an accurate diagnosis and consider a therapeutic trial of steroids. Furthermore, the early PET response to treatment can be pivotal in differentiating between sarcoidosis and malignancy, especially in complex clinical scenarios. Proper differentiation is paramount to avoid therapeutic missteps and ensure appropriate patient management.

Clinical characteristics of hypersensitivity pneumonitis: non-fibrotic and fibrotic subtypes

BACKGROUND

The presence of fibrosis is a criterion for subtype classification in the newly updated hypersensitivity pneumonitis (HP) guidelines. The present study aimed to summarize differences in clinical characteristics and prognosis of non-fibrotic hypersensitivity pneumonitis (NFHP) and fibrotic hypersensitivity pneumonitis (FHP) and explore factors associated with the presence of fibrosis.

METHODS

In this prospective cohort study, patients diagnosed with HP through a multidisciplinary discussion were enrolled. Collected data included demographic and clinical characteristics, laboratory findings, and radiologic and histopathological features. Logistic regression analyses were performed to explore factors related to the presence of fibrosis.

RESULTS

A total of 202 patients with HP were enrolled, including 87 (43.1%) NFHP patients and 115 (56.9%) FHP patients. Patients with FHP were older and more frequently presented with dyspnea, crackles, and digital clubbing than patients with NFHP. Serum levels of carcinoembryonic antigen, carbohydrate antigen 125, carbohydrate antigen 153, gastrin-releasing peptide precursor, squamous cell carcinoma antigen, and antigen cytokeratin 21-1, and count of bronchoalveolar lavage (BAL) eosinophils were higher in the FHP group than in the NFHP group. BAL lymphocytosis was present in both groups, but less pronounced in the FHP group. Multivariable regression analyses revealed that older age, <20% of lymphocyte in BAL, and ≥1.75% of eosinophil in BAL were risk factors for the development of FHP. Twelve patients developed adverse outcomes, with a median survival time of 12.5 months, all of whom had FHP.

CONCLUSIONS

Older age, <20% of lymphocyte in BAL, and ≥1.75% of eosinophil in BAL were risk factors associated with the development of FHP. Prognosis of patients with NFHP was better than that of patients with FHP. These results may provide insights into the mechanisms of fibrosis in HP.

Heterogeneity of determining disease severity, clinical course and outcomes in systemic sclerosis-associated interstitial lung disease: a systematic literature review

Objective The course of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is highly variable and different from continuously progressive idiopathic pulmonary fibrosis (IPF). Most proposed definitions of progressive pulmonary fibrosis or SSc-ILD severity are based on the research data from patients with IPF and are not validated for patients with SSc-ILD. Our study aimed to gather the current evidence for severity, progression and outcomes of SSc-ILD.Methods A systematic literature review to search for definitions of severity, progression and outcomes recorded for SSc-ILD was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in Medline, Embase, Web of Science and Cochrane Library up to 1 August 2023.Results A total of 9054 papers were reviewed and 342 were finally included. The most frequent tools used for the definition of SSc-ILD progression and severity were combined changes of carbon monoxide diffusing capacity (DLCO) and forced vital capacity (FVC), isolated FVC or DLCO changes, high-resolution CT (HRCT) extension and composite algorithms including pulmonary function test, clinical signs and HRCT data. Mortality was the most frequently reported long-term event, both from all causes or ILD related.Conclusions The studies presenting definitions of SSc-ILD 'progression', 'severity' and 'outcome' show a large heterogeneity. These results emphasise the need for developing a standardised, consensus definition of severe SSc-ILD, to link a disease specific definition of progression as a surrogate outcome for clinical trials and clinical practice.PROSPERO registration number CRD42022379254.Cite Now.

Biomarkers in Systemic Sclerosis Associated Interstitial Lung Disease (SSc-ILD)

Purpose of Review

Interstitial lung disease (ILD) is the leading cause of mortality in systemic sclerosis, a rare autoimmune disease characterised by fibrosis and vasculopathy. The variety of phenotypes in SSc-ILD have inspired multiple studies aimed at the identification of biomarkers which can provide disease-specific information but due to the complex pathogenesis of SSc-ILD, it has been challenging to validate such markers. We provide a comprehensive update on those most studied along with emerging biomarkers.

Recent Findings

We review the up-to-date findings with regard to the use of well-studied molecular biomarkers in SSc-ILD along with novel biomarkers offering promise as prognostic markers such as IGFBP-2 and IGFBP-7, the adipokine CTRP9, endothelial progenitor cells, and cellular markers such as CD21lo/neg B cells. Expression profiling data is being used in SSc patients to determine genetic and epigenetic clusters which shed further light on mechanisms involved in the pathogenesis of SSc-ILD and are likely to uncover novel biomarkers.

Summary

With the exception of autoantibodies, there are no routinely measured biomarkers in SSc-ILD and reliable validation of the many potential biomarkers is lacking. Identifying biomarkers which can offer diagnostic and prognostic certainty may help patients to receive preventative treatment as part of a personalised medicine approach.

Changes of Tumor Markers in Patients with Breast Cancer during Postoperative Adjuvant Chemotherapy

Objective

Serum tumor marker (STM) elevation can detect metastasis earlier than imaging diagnosis and, although not recommended by guidelines, is still widely used in clinical practice for postoperative follow-up of breast cancer patients. The purpose of this study was to investigate the change rules of CEA and CA153 in patients with HER2-negative breast cancer during postoperative adjuvant chemotherapy and their influencing factors.

Materials and Methods

The medical records of patients with HER2-negative early breast cancer who visited Xuanwu Hospital from September 2018 to June 2021 were retrospectively analyzed. Demographic characteristics and baseline data of CEA and CA153 at initial diagnosis were collected. Data of CEA, CA153, biochemistry (including ALT, AST, rGT, triglycerides, cholesterol, and blood glucose) and blood routine (including white blood cells, neutrophils, monocytes, lymphocytes, and platelets) were also collected before chemotherapy, at the end of chemotherapy and more than 3 months after the end of chemotherapy. LY/MONO, NEUT/LY, PLT/LY, and systemic immune inflammation index (SII) were calculated and statistically analyzed using SPSSAU software.

Results

A total of 90 patients were enrolled, all of whom were female, with a mean age of 55.11 ± 10.60 y. The value of CEA at initial diagnosis was 2.10 ± 1.11 ng/mL, and high expression was mostly correlated with past history of chronic diseases and tumor lymph node metastasis; the value of CA153 was 11.80 ± 6.60 U/mL, and high expression was correlated with high SII at initial diagnosis. Surgery did not affect the values of serum CEA and CA153. At the end of chemotherapy, CEA and CA153 were 2.68 ± 1.34 ng/mL and 18.51 ± 8.50 U/mL, respectively, which were significantly increased compared with those before chemotherapy, and were linearly correlated with the values before chemotherapy. They decreased (CEA 2.45 ± 1.19 ng/mL, CA153 10.87 ± 5.96 U/mL) again three months after the end of chemotherapy, manifested as "spiking" phenomenon, which was associated with lymph node metastasis at diagnosis, body metabolic disorders, and chronic inflammatory status.

Conclusion

CEA and CA153 were increased presenting as "spiking" phenomena in patients with early HER2-negative breast cancer during postoperative adjuvant chemotherapy, and the peak of increase was linearly correlated with the indicators before chemotherapy. Clinical attention should be paid to this change to avoid excessive diagnosis and treatment leading to medical resource consumption.

CA 15-3 prognostic biomarker in SARS-CoV-2 pneumonia

The severity of lung involvement is the main prognostic factor in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Carbohydrate antigen 15-3 (CA 15-3), a marker of lung damage and fibrosis, could help predict the prognosis of SARS-CoV-2 pneumonia. This was a retrospective and observational study. CA 15-3 was analyzed in the blood samples of patients consecutively admitted for SARS-CoV-2 pneumonia and whose blood samples were available in the biobank. Other prognostic markers were also measured (interleukin 6 [IL6], C-reactive protein [CRP], D-dimer, troponin T, and NT-ProBNP). The occurrence of in-hospital complications was registered, including death, the need for medical intensive care, and oxygen therapy at discharge. In this study, 539 patients were recruited (54.9% men, mean age: 59.6 ± 16.4 years). At admission, the mean concentrations of CA 15-3 was 20.5 ± 15.8 U/mL, and the concentration was correlated with male sex, older age, and other severity markers of coronavirus disease of 2019 (COVID-19) (IL6, CRP, D-dimer, troponine T, and NT-ProBNP). CA 15-3 levels were higher in patients who died (n = 56, 10.4%) (35.33 ± 30.45 vs. 18.8 ± 12.11, p < 0.001), who required intensive medical support (n = 78, 14.4%; 31.17 ± 27.83 vs. 18.68 ± 11.83; p < 0.001), and who were discharged with supplemental oxygen (n = 64, 13.3%; 22.65 ± 14.41 vs. 18.2 ± 11.7; p = 0.011). Elevated CA 15-3 levels (above 34.5 U/mL) were a strong predictor of a complicated in-hospital course, in terms of a higher risk of death (adjusted odds ratio [OR] 3.74, 95% confidence interval [CI]: 1.22–11.9, p = 0.022) and need for intensive care (adjusted OR 4.56, 95% CI: 1.37–15.8) after adjusting for all other risk factors. The degree of lung damage and fibrosis evaluated in terms of CA 15-3 concentrations may allow early identification of the increased risk of complications in patients with SARS-CoV-2 pneumonia.

Correlation Between Serum Tumor Marker Levels and Connective Tissue Disease-Related Interstitial Lung Disease

Objective

The main aims of this study were to explore the relationships between serum tumor markers and connective tissue disease-related interstitial lung disease (CTD-ILD) and to evaluate the clinical value of tumor markers for investigating interstitial lung disease (ILD) in patients with connective tissue disease (CTD).

Methods

The study included 235 patients with CTD (90 CTD without ILDs, 145 CTD-ILD). Clinical information and the levels of inflammatory and tumor markers, including carbohydrate antigen (CA) 19-9, CA125, carcinoembryonic antigen (CEA), CA153, and cytokeratin 19 fragments (CYFRA21-1), were obtained in all the patients.

Results

A significant difference between CTD with or without ILD and higher levels of tumor markers was observed in the CTD-ILD group, including CA19-9 (p<0.001), CEA (p<0.001), CA153 (p<0.001), and CYFRA21-1 (p<0.001). There was no significant difference in serum tumor marker levels in the various types of CTD (rheumatoid arthritis, systemic lupus erythematosus, Sjogren's syndrome, inflammatory myositis, systemic sclerosis, and mixed connective tissue disease). The levels of CA153 [odds ratio (OR)=1.159] and CYFRA21-1 (OR=2.269) were clearly related to the risk of CTD-ILD. The diagnostic value of CA153 [area under receiver operating characteristic curve (AUC)=0.736] and CYFRA21-1 (AUC=0.718) was confirmed for ILDs in CTD patients, at cut-off values of 9.45 U/mL and 2.13 ng/mL, respectively.

Conclusion

There is a positive correlation between serum tumor marker levels and CTD-ILD. Higher levels of CA153 and CYFRA21-1 suggest an increased risk of developing ILD and may therefore be useful as biomarkers for detecting CTD-ILD in the clinical setting.

Carbohydrate antigen 15-3 as a marker of disease severity in patients with chronic hypersensitivity pneumonitis

Objective:

Biomarkers associated with mucin 1, such as Krebs von den Lungen-6 and carbohydrate antigen (CA) 15-3, are increased in various interstitial lung diseases. Our aim was to determine whether CA 15-3 could be considered a biomarker of disease severity in patients with chronic hypersensitivity pneumonitis (cHP).

Methods:

This was a prospective observational study involving adult patients with cHP. Serum levels of CA 15-3 were measured and were correlated with variables related to disease severity and extension. HRCT scans were quantitatively analyzed using a computational platform and an image analysis tool (Computer Aided Lung Informatics for Pathology Evaluation and Rating). CA 15-3 levels were normalized by logarithmic transformation.

Results:

The sample comprised 41 patients. The mean age of the patients was 60.1 ± 11.6 years. The mean FVC in % of predicted was 70.3% ± 17.3%, and the median of the serum level of CA 15-3 was 48.1 U/mL. CA 15-3 levels inversely correlated with FVC in % of predicted (r = −0,30; p = 0,05), DLCO in % of predicted (r = −0,54; p < 0,01), and SpO₂ at the end of a 4-min step test (r = −0,59; p < 0,01), but they directly correlated with total quantitative HRCT scores (r = 0,47; p = 0,004), especially regarding ground-glass opacities (r = 0.58; p < 0,001).

Conclusions:

CA 15-3 is likely to be a biomarker of disease severity of patients with cHP, particularly regarding gas exchange abnormalities.

Large-Scale Characterization of Systemic Sclerosis Serum Protein Profile: Comparison to Peripheral Blood Cell Transcriptome and Correlations With Skin/Lung Fibrosis

OBJECTIVE

To provide a large-scale assessment of serum protein dysregulation in diffuse cutaneous systemic sclerosis (dcSSc) and to investigate serum protein correlates of SSc fibrotic features.

METHODS

We investigated serum protein profiles of 66 participants with dcSSc at baseline who were enrolled in the Scleroderma: Cyclophosphamide or Transplant Trial and 66 age- and sex-matched healthy control subjects. A panel of 230 proteins, including several cytokines and chemokines, was investigated. Whole blood gene expression profiling in concomitantly collected samples was performed.

RESULTS

Among the participants with dcSSc, the mean disease duration was 2.3 years. All had interstitial lung disease (ILD), and none were being treated with immunosuppressive agents at baseline. Ninety proteins were differentially expressed in participants with dcSSc compared to healthy control subjects. Similar to previous global skin transcript results, hepatic fibrosis, granulocyte and agranulocyte adhesion, and diapedesis were the top overrepresented pathways. Eighteen proteins correlated with the modified Rodnan skin thickness score (MRSS). Soluble epidermal growth factor receptor was significantly down-regulated in dcSSc and showed the strongest negative correlation with the MRSS, being predictive of the score's course over time, whereas α₁ -antichymotrypsin was significantly up-regulated in dcSSc and showed the strongest positive correlation with the MRSS. Furthermore, higher levels of cancer antigen 15-3 correlated with more severe ILD, based on findings of reduced forced vital capacity and higher scores of disease activity on high-resolution computed tomography. Only 14 genes showed significant differential expression in the same direction in serum protein and whole blood RNA gene expression analyses.

CONCLUSION

Diffuse cutaneous SSc has a distinct serum protein profile with prominent dysregulation of proteins related to fibrosis and immune cell adhesion/diapedesis. The differential expression for most serum proteins in SSc is likely to originate outside the peripheral blood cells.

Increases in tumor markers are associated with primary Sjögren's syndrome-associated interstitial lung disease

Aims:

Interstitial lung disease (ILD) is the most common type of pulmonary involvement of extraglandular complication in patients with primary Sjögren’s syndrome (pSS), but the diagnosis of pSS-associated ILD (pSS-ILD) is still challenging. This study aimed to investigate the levels of serum tumor markers in pSS patients with or without ILD (pSS-non-ILD) and explore its diagnostic value for pSS-ILD.

Methods:

A total of 168 pSS-ILD patients and age- and sex-matched 538 pSS-non-ILD were recruited. The levels of peripheral tumor markers, including carbohydrate antigen (CA)153, CA125, CA19-9, carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), β-human chorionic gonadotropin, alpha fetoprotein, CA724, and complexed prostate specific antigen, the clinical manifestations, and general laboratory indicators were measured and collected.

Results:

Compared with pSS-non-ILD, pSS-ILD patients had higher levels of disease activity indicators, such as EULAR Sjögren’s syndrome disease activity index, ESR, and CRP, and elevated serum levels of tumor markers: NSE, CEA, CA125, and CA153. The serum levels of CA153 [odds ratio (OR) = 4.521, 95% confidence interval (CI) = [1.871, 10.928)] and CEA [OR = 2.879, 95% CI = (1.305, 6.353)] were significantly correlated with the onset of SS-ILD. CA153 was the only tumor marker with area under receiver operating characteristic curve (AUC) over 0.7 [AUC = 0.743, 95% CI = (0.70, 0.79)].

Conclusion:

Tumor markers increased in serum of pSS-ILD patients. Higher CA153 levels are significantly correlated to the increased risk of ILD in patients with pSS and may be directly involved in the pathogenesis of pSS-ILD. Serum CA153 had the best diagnostic value in those tumor markers for pSS-ILD without malignancy.

Serum biomarker CA 15-3 as predictor of response to antifibrotic treatment and survival in idiopathic pulmonary fibrosis

Aim: Cancer antigen 15-3 (CA 15-3) is a baseline biomarker in idiopathic pulmonary fibrosis (IPF), but its value during follow-up is unknown. Materials and methods: Associations between serum CA 15-3 and pulmonary function tests during 1-year follow-up were evaluated by a mixed model in 132 IPF treated with pirfenidone or nintedanib. Results: Increased baseline (median: 56 kU/l) and follow-up CA 15-3 levels were inversely associated with forced vital capacity and diffusing capacity of the lung for carbon monoxide (estimates respectively: -5.21 and -4.69; p < 0.001). Baseline and 6-month CA 15-3 above 58.5 (hazard ratio: 1.67; p = 0.031) and 50.5 kU/l (hazard ratio: 2.99; p < 0.001), respectively, showed impaired survival compared with lower levels. Conclusion: CA 15-3 is associated with pulmonary function test during follow-up in IPF on antifibrotic treatment. Higher (follow-up) values are related with poor survival. Therefore, CA 15-3 is a promising follow-up biomarker in IPF.

Circulating biomarkers of systemic sclerosis - interstitial lung disease

Interstitial lung disease is a frequent organ manifestation in systemic sclerosis and is associated with high mortality. It is crucial to diagnose interstitial lung disease in systemic sclerosis and to assess severity and identify patients prone to progression at an early stage to ultimately decrease organ damage and improve outcome. Circulating anti-topoisomerase-I autoantibodies have long been associated with the presence and development of systemic sclerosis - interstitial lung disease, evidence on their potential to further predict the clinical course of systemic sclerosis is however conflicting. C-reactive protein is a marker of infection and systemic inflammation with widespread clinical application and is elevated in systemic sclerosis with a tendency towards higher abundancy in patients with early disease. The role of other circulating biomarkers is promising but hampered by the lack of standardized criteria and guidelines for sample/data collection, analyses, reporting and validation and has not reached prime time for clinical application. However, epithelial markers including Krebs von den Lungen-6 and surfactant protein D and several cytokines and chemokines including CCL2 and CCL18 for severity assessment of systemic sclerosis - interstitial lung disease patients at the time of interstitial lung disease diagnosis and to predict interstitial lung disease progression have been reported and seem to be promising candidate biomarkers in the future.

Systemic sclerosis-associated interstitial lung disease

Systemic sclerosis is an autoimmune connective tissue disease, which is characterised by immune dysregulation and progressive fibrosis that typically affects the skin, with variable internal organ involvement. It is a rare condition that affects mostly young and middle-aged women, resulting in disproportionate morbidity and mortality. Currently, interstitial lung disease is the most common cause of death among patients with systemic sclerosis, with a prevalence of up to 30% and a 10-year mortality of up to 40%. Interstitial lung disease is more common among African Americans and in people with the diffuse cutaneous form of systemic sclerosis or anti-topoisomerase 1 antibodies. Systemic sclerosis-associated interstitial lung disease most commonly presents with dyspnoea, cough, and a non-specific interstitial pneumonia pattern on CT scan, with a minority of cases fulfilling the criteria for usual interstitial pneumonia. The standard therapy has traditionally been combinations of immunosuppressants, particularly mycophenolate mofetil or cyclophosphamide. These immunosuppressants can be supplemented by targeted biological and antifibrotic therapies, whereas autologous haematopoietic stem-cell transplantation and lung transplantation are reserved for refractory cases.

Association of serum tumor markers with interstitial lung disease in patients with or without connective tissue disease: A cross-sectional study

Background: Serum markers, such as Krebs von den Lungen-6 (KL-6), are reported to reflect the severity, progression and prognosis of idiopathic pulmonary fibrosis (IPF). We aimed to evaluate whether tumor markers could improve the diagnosis of connective tissue diseases (CTDs) and predict CTD-related interstitial lung diseases (ILDs) (CTD–ILD); and whether there was a significant difference between ILD patients with CTD and without CTD (non-CTD–ILD).

Methods: In this study, 146 patients with ILD only, 61 with CTD–ILD, 102 with lung cancer (LC), 111 with COPD, and 46 with CTD were enrolled. Serum levels of several tumor markers were collected.

Results: Compared with COPD, the serum levels of CEA, NSE, CYFRA21-1, CA19-9 and CA125 were higher, but the level of SCC was lower; meanwhile, there were significant differences in NSE, SCC, CYFRA21-1 and CA125 between CTD–ILD and non-CTD–ILD groups.

Conclusions: It appears that tumor-associated antigens may be the predictive factors for CTD–ILD that could be used to identify CTD from ILD before it is detected on autoimmune symptoms or auto-antibodies. However, further studies are needed to validate our findings and determine whether serum tumor markers have prognostic value or predict progressive CTD–ILD.

Pulmonary function tests as outcomes for systemic sclerosis interstitial lung disease

Interstitial lung disease (ILD) is the leading cause of morbidity and mortality in systemic sclerosis (SSc). We performed a systematic review to characterise the use and validation of pulmonary function tests (PFTs) as surrogate markers for systemic sclerosis-associated interstitial lung disease (SSc-ILD) progression.Five electronic databases were searched to identify all relevant studies. Included studies either used at least one PFT measure as a longitudinal outcome for SSc-ILD progression (i.e. outcome studies) and/or reported at least one classical measure of validity for the PFTs in SSc-ILD (i.e. validation studies).This systematic review included 169 outcome studies and 50 validation studies. Diffusing capacity of the lung for carbon monoxide (DLCO) was cumulatively the most commonly used outcome until 2010 when it was surpassed by forced vital capacity (FVC). FVC (% predicted) was the primary endpoint in 70.4% of studies, compared to 11.3% for % predicted DLCO Only five studies specifically aimed to validate the PFTs: two concluded that DLCO was the best measure of SSc-ILD extent, while the others did not favour any PFT. These studies also showed respectable validity measures for total lung capacity (TLC).Despite the current preference for FVC, available evidence suggests that DLCO and TLC should not yet be discounted as potential surrogate markers for SSc-ILD progression.

Elevated Serum Krebs von den Lungen-6 in Early Disease Predicts Subsequent Deterioration of Pulmonary Function in Patients with Systemic Sclerosis and Interstitial Lung Disease

Objective.

To identify predictors of poor prognosis in patients with systemic sclerosis (SSc) associated with interstitial lung disease (ILD).

Methods.

Fifty patients with early-stage SSc-ILD who had never received disease-modifying drugs and were either observed for ≥ 10 years or died from ILD-related causes were enrolled. The baseline variables of patients who developed endstage lung disease (ESLD) were compared with those of patients who remained ESLD-free, and the Cox proportional hazard model was used to identify initial factors that correlated with ESLD development.

Results.

Sixteen patients (32%) developed ESLD during 173.5 ± 64.7 months of followup. Elevated serum Krebs von den Lungen-6 (KL-6) at initial assessment was highly correlated with ESLD development (p = 0.0002). Receiver-operating characteristic curve analysis revealed that a KL-6 value of 1273 U/ml effectively discriminated patients who developed ESLD from those who did not. Patients with KL-6 > 1273 U/ml were less likely to remain ESLD-free compared with those with lower KL-6 levels (p < 0.0001). Multivariate analysis showed that KL-6 > 1273 U/ml was the most reliable predictor of ESLD development (OR 51.2, 95% CI 7.6–343, p < 0.0001). Finally, the initial KL-6 level correlated with the forced vital capacity (FVC) decline rate (r = 0.58, p < 0.0001).

Conclusion.

The natural course of SSc-ILD is highly variable. Baseline serum KL-6 is a biomarker potentially useful for predicting FVC decline.