The Interobserver Variability for Diagnosing Pulmonary Carcinoid Tumor

Background : Although the grade of pulmonary carcinoid tumor is routinely reported in pathology practice, there is a paucity of data on the level of agreement between pathologists. Methods : Data for 30 cases of surgically resected pulmonary tumors diagnosed as carcinoid tumors (19 typical carcinoids [TCs] and 11 atypical carcinoids [ACs]) were retrieved from four university hospitals. These cases were independently evaluated by five pathologists and were classified according to the 2004 World Health Organization (WHO) classification. Agreement was regarded as “nanimous”if all five pathologists agreed, and as a “ajority”if four agreed. The kappa statistic was calculated to measure the degree of agreement between pathologists. Results : Unanimous agreement was achieved for 50.0% and a majority agreement for 83.3% of the 30 cases. The range of the kappa values extended from 0.37 to 0.89. After a consensus meeting, there was disagreement between the original diagnosis by each institute and the consensus diagnosis by the five pathologists for 40.0% of the 30 cases. Based on the consensus diagnosis, the agreement was greater for TCs than that for ACs. Conclusions : Discriminating carcinoid tumors is subject to interobserver variability. This study indicates that there is a need for more careful standardization and application of diagnostic criteria for making the diagnosis of pulmonary carcinoid tumor. Background : Although the grade of pulmonary carcinoid tumor is routinely reported in pathology practice, there is a paucity of data on the level of agreement between pathologists. Methods : Data for 30 cases of surgically resected pulmonary tumors diagnosed as carcinoid tumors (19 typical carcinoids [TCs] and 11 atypical carcinoids [ACs]) were retrieved from four university hospitals. These cases were independently evaluated by five pathologists and were classified according to the 2004 World Health Organization (WHO) classification. Agreement was regarded as “nanimous”if all five pathologists agreed, and as a “ajority”if four agreed. The kappa statistic was calculated to measure the degree of agreement between pathologists. Results : Unanimous agreement was achieved for 50.0% and a majority agreement for 83.3% of the 30 cases. The range of the kappa values extended from 0.37 to 0.89. After a consensus meeting, there was disagreement between the original diagnosis by each institute and the consensus diagnosis by the five pathologists for 40.0% of the 30 cases. B