Abstract
We attempted to clarify whether serum levels of a carboxy-terminal fragment of ProGRP, ProGRP(31-98), could serve as a more accurate tumour marker in patients with SCLC than neuron-specific enolase (NSE). ProGRP(31-98) and NSE were measured retrospectively in 101 newly diagnosed untreated patients with SCLC, 111 with non-small-cell lung cancer (NSCLC) and 114 patients with non-malignant lung diseases. ProGRP(31-98) and NSE levels were determined using a sandwich enzyme-linked immunosorbent assay. Sensitivity in SCLC patients was 72.3% for ProGRP(31-98) and 62.4% for NSE. Comparing the area under curve (AUC) of 'receiver operator characteristics' of ProGRP(31-98) with that of NSE, ProGRP(31-98) was the more powerful marker in the diagnosis of SCLC (P = 0.0001). Serum levels of ProGRP(31-98) were higher in the 40 patients with extensive disease than in the 61 patients with limited disease (P = 0.0082). ProGRP(31-98) was significantly higher in patients with pure small-cell carcinoma than in patients with mixed small-cell/large-cell carcinoma (P = 0.02). In serial measurement in 16 patients responding to treatment, a high degree of correlation was noted between the decrease in serum ProGRP(31-98) levels and clinical response during the second week after treatment (P = 0.0045). These results indicate that the determination of serum ProGRP(31-98) levels plays an important role in the diagnosis and treatment of SCLC patients.
Highlights
Materials and methodsA total of 212 consecutive samples (Table I) of frozen serum stored at -80°C were retrospectively examined
In 95% of the non-malignant lung diseases, ProGRP(31 -98) values were below 33.8 pg ml- and neuron-specific enolase (NSE) values were below 10.6 ng ml
ProGRP(31-98) levels in the 40 patients with extensive small-cell lung cancer (SCLC) were higher in the 11 patients who had two or more metastatic sites than in the 29 who had only one site, there was no significant difference between the groups (P = 0.22)
Summary
A total of 212 consecutive samples (Table I) of frozen serum stored at -80°C were retrospectively examined. Control blood samples were obtained during routine haematology from 114 patients attending our hospital for a variety of non-malignant lung disease (Table I). Diagnoses in these patients were established on the basis of clinical, radiological and laboratory criteria. The variability and accuracy of this assay will be described by Aoyagi et al (1995) This ELISA for ProGRP(31-98) can be measured within about 2 h in clinical use. This Program calculates maximum likelihood estimates of the parameters of a 'bivariate binormal' model for continuously distributed data from two potentially correlated diagnostic tests. The CLABROC algorithm, developed by Professor CE Metz at the University of Chicago, is a version of the CORROC algorithm (Metz et al, 1984) that has been modified to analyse continuously distributed data (Metz et al, 1990)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
