A comparison between three commercial kits for chromogranin A measurements

Abstract

Chromogranin (CgA) has been shown to be an excellent marker for neuroendocrine tumours. There are now three commercial assays on the market. We wanted to compare the usefulness of the different kits in a clinical situation. We have thus measured CgA in 77 patients and compared the results from the different methods. CgA was measured with three different commercial kits according to the recommendations from the manufacturers (CGA-RIA CT; CIS bio international, Gif-sur-Yvette cedex, France, DAKO Chromogranin A ELISA kit; DAKO A/S, Glostrup, Denmark and CgA; EuroDiagnostica, Malmö, Sweden). The sensitivity and specificity differed between the different kits. The CIS kit showed a sensitivity of 67% and a specificity of 96%. The sensitivity and specificity were both 85% for the DAKO kit and 93% and 88% respectively for the EuroDiagnostica assay. We have concluded that CgA is an important tumour marker for all neuroendocrine tumours. However, different analytical properties of the respective kits give different performances, a fact that must be taken into consideration when comparing results from different clinical studies. A recognised international standard for CgA would be a step on the way to harmonisation, but antibody selection and construction of the assays will probably still influence the results.

Circulating biomarkers in gastroenteropancreatic neuroendocrine tumours

“…pancreastatin) usually have lower sensitivity in detecting patients with NETs (Tatemoto et al 1986, O'Toole et al 2009, Vinik et al 2009). Commercial kits for determining CgA are available and measurement of CgA is routine in the management of NETs (Stridsberg et al 2003, O'Toole et al 2009). It should be noted, however, that there is a fair amount of variability between assays with sensitivities varying from 67 to 93% depending on which assay is used (Stridsberg et al 2003, O'Toole et al 2009).…”

“…Commercial kits for determining CgA are available and measurement of CgA is routine in the management of NETs (Stridsberg et al 2003, O'Toole et al 2009). It should be noted, however, that there is a fair amount of variability between assays with sensitivities varying from 67 to 93% depending on which assay is used (Stridsberg et al 2003, O'Toole et al 2009). In most NETs, CgA is more abundant than CgB and thus CgA is usually a better circulating tumour marker than is CgB (Fig.…”

Significance of plasma chromogranin A determination in neuroendocrine tumour (NET) diagnosis.

“…Using the same cut-off point (18 U/l) as in our study, they received greater diagnostic sensitivity (85%) and specificity (96%) for the diagnosis of NET. With cut-off values from 17 to 34 U/l the estimated value of the diagnostic sensitivity of CgA from 79 to 92% [30,33] and specificity from 83 to 91% [22,30,33] was obtained in various other studies.…”

Chromogranin A and Neuroendocrine Tumors

“…Intra-assay coefficients of variation were 4.5, 3.8 and 8.5% for the following ranges 5-10, 15-25 and 250-450 U/l, respectively (Zatelli et al, 2007). The three most commonly available employed assays for CgA measurement, has been compared in a group of NET patients and has been found that sensitivities vary between 67 and 93%, while specificities were 1 to 85% for all three (Stridsberg et al, 2003). A recent multicenter prospective comparison between two methods, immunoradiometric and ELISA, found a 36% clinical discordance rate.…”