Factors associated with relapse and survival in Wilms tumor: a multivariate analysis

PurposeLymph node metastasis and anaplasia predict relapse-free survival in Wilms tumor. We performed a multivariate analysis of our institutional database to identify factors independently associated with relapse-free and overall survival.MethodsWe retrospectively reviewed cases of confirmed Wilms tumor diagnosed between 1990 and 2010 and treated at our institution. The log-rank test was used to screen variables for consideration in the proportional hazards model.ResultsA total of 95 patients were treated at our institution during the study period, with a median follow-up of 3.3 years. Factors correlated with overall survival in the univariate analysis were local disease, metastasis, tumor size, anaplasia, renal vein tumor thrombus, inferior vena cava tumor thrombus, lymph node positivity, and tumor rupture. On multivariate analysis, factors associated with increased risk of death were lymph node positivity and anaplasia. Factors correlated with probability of relapse in the univariate analysis were lymph node positivity, anaplasia, and female sex. All 3 of these factors were also independently significant on multivariate analysis.ConclusionLymph node involvement and anaplasia are significantly correlated with probability of relapse and overall survival, reemphasizing the strong recommendation to sample regional lymph nodes during Wilms tumor resection.