Abstract
Aims: To test the reproducibility of the current World Health Organization (WHO) classification of thymic epithelial tumours and to determine the level of interobserver variation within a group of pathologists, all with experience and expertise in thoracic pathology. Methods and results: Ninety-five thymic tumours were circulated to a group of 17 pathologists in the UK and The Netherlands over a 1-year period. Participants were asked to classify them according to WHO criteria. The diagnoses were subjected to statistical analysis and K values calculated. The overall level of agreement was moderate (kappa 0.45). When the categories were reduced in number by creating two groups. (A + AB + B1 + B2 and B3 + C), the level of agreement increased to 0.62. An alternative grouping (A + AB + B1 and B2 + B3 + C) increased it slightly further. The best agreement was in tumour types A and AB. Difficulties arose in distinguishing B1 tumours from B2 tumours and B2 tumours from B3 tumours. Conclusions: Although the WHO system describes a number of well-defined tumour types with clear diagnostic criteria, the overall level of agreement was moderate and improved if some groups were amalgamated.
Original language | Undefined/Unknown |
---|---|
Pages (from-to) | 218-223 |
Number of pages | 6 |
Journal | Histopathology |
Volume | 53 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2008 |
Research programs
- EMC MM-03-24-01
- EMC NIHES-01-66-01