MESOMARK: a potential test for malignant pleural mesothelioma.
BACKGROUND
Soluble mesothelin-related peptides (SMRP)have been reported to be potential biomarkers for malignant pleural mesothelioma (MPM). We report analytical and preliminary clinical studies of MESOMARK, a quantitative assay for SMRP.


METHODS
The MESOMARK assay is a 2-step immunoenzymatic assay in an ELISA format with a 6-point calibration curve (0-32 nmol/L). We assessed analytical imprecision, analyte stability, and analytical interferences. We measured SMRP by this assay in 409 apparently healthy individuals (reference interval study), 177 patients with nonmalignant conditions, and 500 cancer patients, including 88 with MPM.


RESULTS
The limit of detection was 0.16 nmol/L. At 2-19 nmol/L, intraassay imprecision (CV) was 1.1%-5.3%, and total imprecision was 4.0%-11.0%. The mean dilution recovery for 5 samples was 109% (range, 99%-113%). No interference was seen from added bilirubin (200 mg/L), hemoglobin (500 mg/L), triglycerides (30 g/L), chemotherapeutic agents, or other tested substances. Recombinant mesothelin was stable in serum upon freeze/thaw at -70 degrees C and upon storage for at least 7 days at 2-8 degrees C. The 99(th) percentile of the reference group was 1.5 nmol/L [95% confidence interval (CI), 1.2-1.6 nmol/L; n = 409], and mean SMRP was significantly higher in sera from patients with MPM (7.5 nmol/L; 95% CI, 2.8-12.1 nmol/L; n = 88). SMRP was increased in 52% and 5% of MPM patients and asbestos-exposed individuals, respectively. Concentrations in other nonmalignant and malignant conditions were similar to those in healthy controls.


CONCLUSIONS
The MESOMARK assay is analytically robust and may be useful for the detection and management of mesothelioma.
Beyer
Heather L
HL
Research and Development Division, Fujirebio Diagnostics, Inc., Malvern, PA 19355, USA.
Geschwindt
Ryan D
RD
Glover
Curtis L
CL
Tran
Ly
L
Hellstrom
Ingegerd
I
Hellstrom
Karl-Erik
KE
Miller
M Craig
MC
Verch
Thorsten
T
Allard
W Jeffrey
WJ
Pass
Harvey I
HI
Sardesai
Niranjan Y
NY
D014408:Biomarkers, Tumor / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D058851:GPI-Linked Proteins; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood*; D000090204:Mesothelin; D008654:Mesothelioma / Q000175:diagnosis*; D010455:Peptides / Q000097:blood*; D010997:Pleural Neoplasms / Q000175:diagnosis*; D012372:ROC Curve; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012995:Solubility
D014408:Biomarkers, Tumor; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; D010455:Peptides; D000090204:Mesothelin