[Gastric cancer: probability assessment after lymph node-negative staging and its consequences]
Juan Manuel Miralles-Tena1, Javier Escrig-Sos, David Martínez-Ramos
1Servicio de Cirugía General y del Aparato Digestivo, Hospital General de Castellón, Castellón, España. jmt@comcas.es
Objective:
To provide an approach to calculating the probability of error after lymph node-negative staging in gastric cancer.
Patients And Method:
Retrospective data of 75 gastric resections for cancer were used to calculate the probability of error in general, according to T staging of the TNM classification (6th edition) and according to the type of lymphadenectomy performed. A modification of a procedure based on Bayes' theorem was used.
Results:
For all tumors, at least 11 negative lymph nodes were required to ensure a true pN0. Two lymph nodes were required for T1 tumors, 11 for T2 tumors, and 14 for T3 tumors. A greater number of lymph nodes were required for a D2 lymphadenectomy than for a D1 lymphadenectomy. However, in D2 lymphadenectomy, pN0 stages were almost always reliable, while in D1 lymphadenectomy 24% of stagings were unreliable.
Conclusions:
The present study describes a simple and reproducible mathematical model that could help surgeons to determine the accuracy of lymph node-negative stages in a substantial group of patients with gastric cancer.
