Remote quantitation server for quality assurance in DNA ploidy analysis.

OBJECTIVE

To remotely test a stepwise framework of quality control measures, developed according to the 1997 European Society of Analytical Cellular Pathology consensus on diagnostic DNA image cytometry, in two series of measurements by means of the quantitation server EUROQUANT.

STUDY DESIGN

In each of these series, 104 fine needle aspiration biopsies, imprints from breast cancer specimens and 28 rat liver imprints were measured twice at two different cytometry workstations. Further measurements on special rat liver specimens for evaluation of the stability of the machinery and of the preparation process were done at both workstations. Afterwards the measurement data from both machines were transferred to the quantitation server and analyzed automatically. Beside the classical DNA histograms, a set of further evaluations was performed to detect optical errors as well as inhomogeneities in the measurements. Running values for mean integrated optical density values, mean corrective factors and mean coefficients of variations of corrective factors were computed to control the stability of the entire methodology over time.

RESULTS

The study demonstrated the preconditions and outcome of server-based quality control in DNA ploidy analysis. The results show that such a remote analysis is feasible and comparable to local DNA ploidy analysis. It is also demonstrated how quality control tests reflect the process performance of ploidy analysis at its different levels.

CONCLUSION

Quality control must be an inherent part of the daily routine to allow a reliable diagnostic interpretation and ensure steadily high product quality.