THE IMPACT OF NUMBER OF LYMPH NODE REMOVED IN THE DETECTION OF LYMPHNODE METASTASIS: A SENSITIVITY CURVE ANALYSIS.

Scopo del lavoro To assess the correct number of lymph nodes (LNs) to removed at Radical Cystectomy (RC) to ensure an accurate lymph nodes metastasis (LNM) staging. Materiali e metodi Between 1995 and 2012, 1016 RC for bladder cancer (BCa) were completed at a single tertiary care institution. Demographical, clinical and pathological variables were recorded for each patient. The relationship between the number of removed LNs and the probability to find a LNI at definitive pathology examination was assessed by receiver operating characteristic (ROC) analyses. The ROC curve coordinates were used to graph the probability of finding LNI according to the number of LNs removed and examined with a sensibility of 90 and 95%. Risultati Among all patients who underwent RC, the prevalence of LNM was 35.7% (363 of 1016). T stage and grade, LVI, LND removed, type of BCa at last TUR and N Radiological Stage were strongly associated with the LNM (all p Discussione The objective of our study was to determine the minimum number of LND to remove during RC to maximize the probability to detect LNM. After assessed this for overall RC population we stratified for clinical and pathological variables in order to tailoring the extension of LN dissection. Conclusioni Our results confirms that an extend pelvic lymphadenectomy is needed in order to improve the sensibility of LNM staging. Considering the overall population, a minimum 28 nodes should be removed for achieving an adequate LNM staging (achieve 75% sensibility). In addition, more extended staging lymphadenectomy could be appropriate in selected cases in which, based on clinical information (such as pre operative CT scan) there are a low probability to have LNM.