Short- and long-term effects of a training session on pathologists' performance: the INQAT experience for histological grading in breast cancer.

Although the introduction of the Nottingham/Tenovus classification has improved the criteria to assess the histological grading in breast cancer, several quality control studies have shown that good results in terms of reproducibility are hard to obtain. This paper reports the results obtained during an implemented quality control programme for histological grading aimed at evaluating the short- and long-term effects of a training session on pathologists' performance. The interobserver reproducibility for grading score along with its components was assessed. The reproducibility between each pathologist and the reference values was also evaluated, as well as the contribution of each grading category to the observed reproducibility. Results show the weakness of a single training course in improving the long-term performance of the participating pathologists, suggesting the need to continuously monitor the quality of the grading determination by planning quality control studies and training sessions sequentially repeated in short time intervals.