Valoración de la 5ª edición de la clasificación TNM para el cáncer gástrico en nuestro medio / Appraisal of the fifth edition of the tumor-node-metastasis (TNM) classification for gastric cancer in our environment

Objetivo. Evaluar el número de casos de carcinoma gástrico que pueden ser estadificados con los criterios de la 5.a edición del sistema TNM y analizar qué factores pueden estar relacionados con la obtención de un número suficiente de ganglios. Pacientes y método. En 164 pacientes a los que se resecó un carcinoma gástrico, se estudiaron distintos factores que podían influir en el número de ganglios aislados, como el tamaño tumoral, el tipo de resección gástrica, el grado de diferenciación tumoral, el tipo histológico, la variabilidad entre patólogos que analizaron las piezas y la experiencia del cirujano. Resultados. La media de ganglios linfáticos analizados por los patólogos fue de 11,4 (intervalo de confianza del 95%, 10,12-12,66). Atendiendo a los criterios de la 5.a edición de la clasificación TNM, sólo se pudo clasificar correctamente al 31% de los pacientes. Encontramos una correlación positiva entre el tamaño tumoral y el número de ganglios aislados (p = 0,0018), así como un mayor número de ganglios analizados en las gastrectomías totales respecto de las subtotales (p = 0,034). No se observó una variación significativa en los ganglios analizados en relación con el patólogo que analizó la pieza ni con la experiencia del cirujano que efectuó la resección. Conclusiones. La 5.a edición del sistema TNM es fácilmente reproducible, aunque el número de ganglios necesarios para corroborar la afección ganglionar metastásica es difícil de conseguir en nuestro medio. Nuestros resultados sugieren que es necesario un esfuerzo conjunto por parte de cirujanos y patólogos para aumentar el número de pacientes estadificables con esta edición (AU)

Aim. To estimate the proportion of patients with gastric carcinoma that can be classified using the criteria of the fifth edition of the TNM system and to analyze which factors could be related to the finding of an adequate number of nodes. Patients and method. The influence of distinct factors that could influence the number of lymph nodes isolated was evaluated in 164 patients who underwent resection of gastric carcinoma. These factors included tumor size, surgical resection, grade, histological type, variability among the pathologists who analyzed the surgical specimens, and the surgeon's experience. Results. The mean number of lymph nodes examined by the pathologists was 11.4 (10.12-12.66). Applying the criteria of the fifth edition of the TNM classification, only 31% of the patients could be correctly classified. A positive correlation was found between tumor size and the number of resected nodes (p = 0.0018). In addition, a greater number of lymph nodes were found in total gastrectomies than in subtotal gastrectomies (p = 0.034). No significant association was found with the pathologist who analyzed the surgical specimen or with the experience of the surgeon who performed the resection. Conclusions. The fifth edition of the TNM system is easily reproducible, although the number of lymph nodes required to evaluate metastatic node involvement is difficult to obtain in our environment. Our results suggest that a combined effort between surgeons and pathologists is needed to increase the number of patients that can be reliably staged with this TNM edition (AU)

[Assessment of the fifth edition of the tumor-node-metastasis (TNM) classification for gastric cancer in our setting]. / Valoración de la 5.a edición de la clasificación TNM para el cáncer gástrico en nuestro medio.

AIM: To estimate the proportion of patients with gastric carcinoma that can be classified using the criteria of the fifth edition of the TNM system and to analyze which factors could be related to the finding of an adequate number of nodes. PATIENTS AND METHOD: The influence of distinct factors that could influence the number of lymph nodes isolated was evaluated in 164 patients who underwent resection of gastric carcinoma. These factors included tumor size, surgical resection, grade, histological type, variability among the pathologists who analyzed the surgical specimens, and the surgeon's experience. RESULTS: The mean number of lymph nodes examined by the pathologists was 11.4 (10.12-12.66). Applying the criteria of the fifth edition of the TNM classification, only 31% of the patients could be correctly classified. A positive correlation was found between tumor size and the number of resected nodes (p = 0.0018). In addition, a greater number of lymph nodes were found in total gastrectomies than in subtotal gastrectomies (p = 0.034). No significant association was found with the pathologist who analyzed the surgical specimen or with the experience of the surgeon who performed the resection. CONCLUSIONS: The fifth edition of the TNM system is easily reproducible, although the number of lymph nodes required to evaluate metastatic node involvement is difficult to obtain in our environment. Our results suggest that a combined effort between surgeons and pathologists is needed to increase the number of patients that can be reliably staged with this TNM edition.