Reproducibilidad interobservador de un sistema de grado para el carcinoma de células renales tipo cromófobo / Interobserver Reproducibility of a Grading System for Chromophobe Renal Cell Carcinoma

Objetivos: Valorar la reproducibilidad interobservador y evaluar el sistema de gradación propuesto por Paner et al. para el carcinoma de células renales cromófobo. Material y métodos: Tras seleccionar 23 casos de carcinoma renal de tipo cromófobo de los hospitales Xeral-Cíes, Meixoeiro y POVISA de Vigo de los últimos 15 años se ha realizado una sesión informativa de los criterios del sistema de gradación de Paner et al. Posteriormente los patólogos observadores han aplicado dicho sistema a cada caso, valorando una laminilla seleccionada. Se ha calculado el índice Kappa de reproducibilidad interobservador, ponderado según la escala de Landis y Koch. Resultados: La distribución de grados en la mayoría de los 6 observadores participantes es similar, con predominio del grado 1 en 4 de los mismos. Los 2 observadores restantes consideraron una mayoría relativa de casos como grado 2. Los valores de Kappa oscilan entre 0,136 y 0,674, observándose un predominio de valores indicadores de reproducibilidad discreta-moderada (0,21-0,60). El mayor valor de Kappa (0,674) se ha dado entre un observador novel y el patólogo más experto. Entre los 2 observadores más veteranos se ha obtenido el índice más bajo (0,136). Conclusiones: La reproducibilidad interobservador en nuestros centros para el grado propuesto por Paner et al. es discreta-moderada. La asignación de los grados 1 y 2 no es homogénea entre los 6 observadores participantes. En espera de la existencia de una gradación consensuada por las sociedades científicas, creemos prudente no utilizar ningún sistema de gradación en los carcinomas de células renales de tipo cromófobo (AU)

Objectives: To evaluate interobserver reproducibility of a grading system proposed by Paner et al. for chromophobe renal cell carcinoma. Material and methods: After selecting 23 cases of chromophobe renal cell carcinoma from the Xeral-Cíes Hospital, Meixoeiro Hospital and POVISA Hospital from the last 15 years, an informative meeting on the Paner et al. grading system criteria was held. After, the participating pathologists applied the system to each case, evaluating one slide selected. Kappa index for interobserver reproducibility was calculated, and it was classified according to the Landis and Koch scale. Results: The grading distribution was similar for most of the 6 participating observers, with grade 1 predominance. The remaining 2 observers considered a relatively higher proportion of grade 2. Kappa index values ranged from 0.136 to 0.674, with a discrete-moderate reproducibility index predominance (0.21-0.60). Highest Kappa value (0.674) was obtained between the most novel and the most expert interobservers. The lowest Kappa value was obtained among the most veteran pathologists (0.136). Conclusions: Interobserver reproducibility for chromophobe renal cell carcinoma is discrete-moderate in our institutions when the novel grade proposed by Paner et al. is used. Labeling of grades 1 and 2 is not homogeneous among 6 participating observers. While awaiting a grading consensus on a new classification by the scientific societies, we consider that the routine use of a grading system for chromophobe renal cell carcinoma should not be used (AU)

Interobserver reproducibility of a grading system for chromophobe renal cell carcinoma.

OBJECTIVES: To evaluate interobserver reproducibility of a grading system proposed by Paner et al. for chromophobe renal cell carcinoma. MATERIAL AND METHODS: After selecting 23 cases of chromophobe renal cell carcinoma from the Xeral-Cíes Hospital, Meixoeiro Hospital and POVISA Hospital from the last 15 years, an informative meeting on the Paner et al. grading system criteria was held. After, the participating pathologists applied the system to each case, evaluating one slide selected. Kappa index for interobserver reproducibility was calculated, and it was classified according to the Landis and Koch scale. RESULTS: The grading distribution was similar for most of the 6 participating observers, with grade 1 predominance. The remaining 2 observers considered a relatively higher proportion of grade 2. Kappa index values ranged from 0.136 to 0.674, with a discrete-moderate reproducibility index predominance (0.21-0.60). Highest Kappa value (0.674) was obtained between the most novel and the most expert interobservers. The lowest Kappa value was obtained among the most veteran pathologists (0.136). CONCLUSIONS: Interobserver reproducibility for chromophobe renal cell carcinoma is discrete-moderate in our institutions when the novel grade proposed by Paner et al. is used. Labeling of grades 1 and 2 is not homogeneous among 6 participating observers. While awaiting a grading consensus on a new classification by the scientific societies, we consider that the routine use of a grading system for chromophobe renal cell carcinoma should not be used.