[How has the Paris System contributed to urine cytology? Evaluating the contribution of the Paris System to urine cytology. A comparative study of the Paris System and the Papanicolaou method in a tertiary centre]. / ¿Qué ha aportado el sistema de París al diagnóstico en citología de orina? Estudio comparativo del sistema de París con el sistema clásico en un centro terciario.

INTRODUCTION AND OBJECTIVES: The Paris System (PS) has replaced the classical Papanicolaou System (PapS) in reporting urine cytology, due to its improved sensitivity and negative predictive value (NPV) without loss of specificity. Furthermore, it has enabled the risk of malignancy to be established in each cytological category. The aim of this study is to compare the Paris System with previous results and determine the changes in sensitivity, specificity, positive predictive value, NPV and risk of malignancy in our centre, MATERIALS AND METHODS: Evaluation of the diagnostic power of urine cytology by means of a retrospective cohort study, comparing two series of 400 cytological studies, one using the Papanicolaou System and the other the Paris System. RESULTS: In the detection of high-grade urothelial carcinoma, Paris System has better specificity (93.82% PapS vs 98.64% PS; P=.001) and PPV (39.5% PapS vs 70.6% PS; P=.044) than Papanicolaou System, without changes in sensitivity (53.5% PapS vs 37.5% PS; P=.299) or NPV (96.4% PapS vs 94.8% PS; P=.183). The risk of malignancy for the atypical category increases from low to high levels (1.6% PapS vs 40.0% PS; P=.001); the other categories showed no significant statistical changes. CONCLUSION: The Paris System improves specificity and positive predictive value and establishes a better indication of risk of malignancy for each category, enabling specific clinical management in each case.

¿Qué ha aportado el sistema de París al diagnóstico en citología de orina? Estudio comparativo del sistema de París con el sistema clásico en un centro terciario / How has the Paris System contributed to urine cytology? Evaluating the contribution of the Paris System to urine cytology. A comparative study of the Paris System and the Papanicolaou method in a tertiary centre

Introducción y objetivos: El sistema de París (SP) ha sustituido al sistema de Papanicolaou (SPap) como sistema de citodiagnóstico de orina. La evidencia indica que el SP ha logrado aumentar la sensibilidad y el valor predictivo negativo (VPN) sin perder especificidad, y establecer un riesgo de malignidad para cada categoría diagnóstica. El objetivo de este estudio es conocer los cambios que han experimentado la sensibilidad, especificidad, valor predictivo positivo (VPP), VPN y el riesgo de malignidad en la transición en nuestro centro. Materiales y métodos: Evaluación de prueba diagnóstica a través de una cohorte retrospectiva en la que se comparan dos series de 400 citologías de orina, una diagnosticada mediante el SPap y otra con SP. Resultados: Para la detección de carcinoma urotelial de alto grado describimos con el SP mejor especificidad (93,82 SPap vs. 98,64% SP; p=0,001) y VPP (39,5 SPap vs. 70,6% SP; p=0,044), sin observar cambios significativos en la sensibilidad (53,5 SPap vs. 37,5% SP; p=0,299) y VPN (96,4 SPap vs. 94,8% SP; p=0,183), respecto al SPap. El riesgo de malignidad en el SP experimenta un cambio estadísticamente significativo para la categoría atipia con respecto a la atipia en el SPap (1,6 SPap vs. 40,0% SP; p=0.001), manteniéndose el resto de las categorías sin cambios estadísticamente significativos. Conclusiones: El SP ha conseguido mejorar la especificidad y el VPP de la citología de orina y establece un riesgo de malignidad propio para la categoría de atipia, permitiendo establecer un manejo específico para cada resultado.(AU)

Introduction and objectives: The Paris System (PS) has replaced the classical Papanicolaou System (PapS) in reporting urine cytology, due to its improved sensitivity and negative predictive value (NPV) without loss of specificity. Furthermore, it has enabled the risk of malignancy to be established in each cytological category. The aim of this study is to compare the Paris System with previous results and determine the changes in sensitivity, specificity, positive predictive value, NPV and risk of malignancy in our centre. Materials and methods: Evaluation of the diagnostic power of urine cytology by means of a retrospective cohort study, comparing two series of 400 cytological studies, one using the Papanicolaou System and the other the Paris System. Results: In the detection of high-grade urothelial carcinoma, Paris System has better specificity (93.82% PapS vs 98.64% PS; P=.001) and PPV (39.5% PapS vs 70.6% PS; P=.044) than Papanicolaou System, without changes in sensitivity (53.5% PapS vs 37.5% PS; P=.299) or NPV (96.4% PapS vs 94.8% PS; P=.183). The risk of malignancy for the atypical category increases from low to high levels (1.6% PapS vs 40.0% PS; P=.001); the other categories showed no significant statistical changes. Conclusion: The Paris System improves specificity and positive predictive value and establishes a better indication of risk of malignancy for each category, enabling specific clinical management in each case.(AU)