Sensitivity of Urinary Mesothelin in Patients with Malignant Mesothelioma

Clinical utility of diagnostic biomarkers in malignant pleural mesothelioma: a systematic review and meta-analysis

Malignant pleural mesothelioma (MPM) is characterised by late-stage diagnosis and poor prognosis. Currently, no screening tool is advocated and diagnosis is based on invasive techniques, which are not well tolerated. Non-invasive diagnostic biomarkers have shown potential and could have a huge clinical benefit. However, despite extensive research, there is no consensus yet on their clinical use, with many articles reporting contradicting results, limiting their clinical implementation. The aim of this systematic review is therefore to explore the different semi- and non-invasive diagnostic markers in several human matrices and identify those that might clinically be relevant. A total of 100 articles were selected through Web of Science and PubMed, with 56 articles included in the quantitative analysis. Although many studies have reported on the diagnostic accuracy of MPM biomarkers such as serum mesothelin and high-mobility group box protein 1 and plasma fibulin-3, none have resulted in a validated test for early detection. Future research should focus on external validation, combinations into biomarker panels, the inclusion of early stage MPM patients and a combination of different biomarker matrices, as well as new markers.

Diagnostic biomarkers for malignant pleural mesothelioma seem promising; however, further research is necessary to prove their clinical value. This review provides a thorough overview of the different markers and compares them in several matrices.https://bit.ly/35ni6UO

Follow-up of Soluble Mesothelin-Related Protein Levels in Participants With Asbestos-Related Disorders

Background

Asbestos exposure is associated with the development of the cancer malignant mesothelioma (MM). Measurement of soluble mesothelin-related protein (SMRP) has been suggested as a method for detection of MM in its early stages. We prospectively examined SMRP levels in participants with asbestos exposure who are a group at a high risk of development of MM.

Methods

This study was a follow-up of our cohort of 322 asbestos-exposed participants. No further participants developed MM or malignancy over the study period. Mean follow-up time was 22.9 months.

Results

Mean (standard deviation) SMRP levels at baseline and follow-up were 0.94 (0.79) and 0.91 (0.86) nmol/L (p = 0.1033), respectively. Mean SMRP levels of the healthy individuals exposed to asbestos at baseline was significantly lower than those of participants with asbestosis and pleural plaques alone; similar patterns were found on follow-up measurements. There was a statistically significant effect of age on serial SMRP measurements. Our study confirms higher levels in participants with nonmalignant asbestos-related disorders. Levels decreased in asbestos-related disorders other than asbestosis, where a small increase was observed. We did not detect any further cases of malignancy.

Conclusion

Monitoring programs for early detection of MM need to take into account increased SMRP levels found in benign asbestos-related diseases.

Mesothelin levels in urine are affected by glomerular leakage and tubular reabsorption

BACKGROUND

Mesothelin is a soluble biomarker of malignant mesothelioma. Levels in serum, however, are also influenced by other factors, including age and glomerular filtration rate (GFR). The measurement of mesothelin in urine has recently gained interest, but the renal handling of this protein has not been sufficiently examined.

PATIENTS AND METHODS

A total of 75 patients with benign kidney disease were prospectively included in the study. Mesothelin levels were measured in the serum and in the urine of all the participants by using enzyme-linked immunosorbent assay. Urinary albumin and alpha 1-microglobulin (A1M) levels, which are markers of glomerular leakage and of decreased tubular reabsorption, respectively, and the estimated GFR (eGFR) of each participant were obtained. All urine analyte levels were standardized (std) against urinary creatinine levels.

RESULTS

Absolute mesothelin levels in urine (median, 0.58 nmol/L; interquartile range [IQR], 0.25-1.03 nmol/L) were significantly lower than those in serum (median, 1.74 nmol/L; IQR, 1.35-2.43 nmol/L; P < .001). Urinary mesothelin(std) levels positively correlated with serum mesothelin (r = 0.35, P < .01), albumin(std) (r = 0.51, P < .001), and A1M(std) levels (r = 0.71, P < .001). Neither age nor eGFR were associated with urinary mesothelin(std) levels. Similarly, multiple linear regression analysis indicated that only albumin(std) and A1M(std) levels were significantly positively associated with the urinary mesothelin(std) levels (adjusted R(2) = 0.49).

CONCLUSION

Mesothelin levels in urine are affected by impaired glomerular and tubular function, which can influence the interpretation of mesothelin measurements and might cause false-positive results. These effects need to be accounted for to improve the further validation and possible clinical use of urinary mesothelin.

Soluble markers for diagnosis of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a highly aggressive and invasive tumor, whose incidence is expected to peak, in many countries, at the end of the present decade, 20–40 years after the peak of asbestos use (asbestos being the most important etiological factor). MPM has a poor prognosis, in part, owing to a difficult and often late diagnosis hindered by a lack of available tests able to diagnose or predict this cancer in its early stages. Recently, there has been increased interest in noninvasive, economic and well-accepted diagnostic tests for screening of asbestos-exposed subjects, as well as for monitoring response of MPM patients to treatment. Several markers have been studied in biofluids, such as serum, plasma and pleural effusions, especially using ELISA, and some of them are still under investigation. However, only mesothelin and ostepontin have proven levels of sensitivity and specificity that are worth testing in the clinical setting.

Mesothelin and kidney function--analysis of relationship and implications for mesothelioma screening

PURPOSE

Malignant mesothelioma (MM) carries a poor prognosis and remains a major public health issue in many countries. Outcomes may be improved with earlier detection and this justifies screening the at-risk asbestos-exposed population. Soluble mesothelin is a potential biomarker for MM, but it has been observed to be elevated in patients with reduced kidney function. Defining the relationship between mesothelin concentrations and kidney function will allow more accurate interpretation of this assay.

MATERIALS AND METHODS

A cross-sectional study consisting of 144 patients with chronic kidney disease (CKD) was conducted at Sir Charles Gairdner Hospital and Royal Perth Hospital in Western Australia. Only patients with CKD stages II-V were recruited while those with a history of renal transplant, dialysis, or malignancy were excluded. Serum and urine mesothelin and creatinine concentrations were determined.

RESULTS

There were 33, 49, 31 and 31 patients in CKD stages II, III, IV and V, respectively recruited. Serum mesothelin increased significantly with increasing serum creatinine (p<0.0001), and worsening stage of CKD (p<0.0001). A significant correlation between urine mesothelin to creatinine ratio and serum mesothelin concentration was detected (p=0.002). No significant difference was found in urine mesothelin to creatinine ratios across the four CKD stage groups.

CONCLUSION

Serum mesothelin concentration is elevated in individuals with renal impairment. Renal function should therefore be taken into account during interpretation of this assay.