RESUMO
PURPOSE: Current investigational priorities in the treatment of favorable histology Wilms tumor (FHWT) center on accurate staging and risk-stratification. The extent of lymph node (LN) sampling has not been clearly defined; its importance cannot be overstated as it guides adjuvant therapy. The identification of a minimum LN yield to minimize the risk of harboring occult metastatic disease could help development of surgical guidelines. This study focuses on using the beta-binomial distribution to estimate the risk of occult metastatic disease in patients with FHWT. MATERIALS & METHODS: The National Cancer Database was queried for patients with unilateral FHWT from 2004 to 2013. Data were used to characterize nodal positivity for patients who underwent surgery and had ≥1 positive LN andâ¯≥2 LNs examined. The probability of missing a positive LN (i.e., false negative) for a given LN yield was calculated using an empirical estimation and the beta-binomial model. Patients were then stratified by tumor size. RESULTS: 422 patients met study criteria. To limit the chance of missing a positive LN to ≤10%, the empirical estimation and beta-binomial model estimated that 6 and 10 LNs needed to be sampled, respectively. Tumor size did not influence the result. Internal validation showed little variation to maintain a false negative rateâ¯≤â¯10%. CONCLUSIONS: Using mathematical modeling, it appears that the desired LN yield in FHWT to reduce the risk of false-negative LN sampling to ≤10% is between 6 and 10. The current analysis represents an objective attempt to determine the desired surgical approach to LN sampling to accurately stage patients with FHWT. LEVEL OF EVIDENCE: II.
Assuntos
Neoplasias Renais , Linfonodos/patologia , Estadiamento de Neoplasias/métodos , Tumor de Wilms , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/patologia , Metástase Linfática/patologia , Modelos Estatísticos , Tumor de Wilms/diagnóstico , Tumor de Wilms/patologiaRESUMO
PURPOSE: We sought to compare the presentation, management, and outcomes in gastric adenocarcinoma cancer for pediatric and adult patients. METHODS: Using the 2004 to 2014 National Cancer Database (NCDB), patients ≤21â¯years (pediatric) were retrospectively compared to >21â¯years (adult). Chi-squared tests were used to compare categorical variables, and Cox regression was used to estimate hazard ratios (HR) for survival differences. RESULTS: Of the 129,024 gastric adenocarcinoma cases identified, 129 (0.10%) occurred in pediatric patients. Pediatric cases presented with more advanced disease, including poorly differentiated tumors (81% vs 65%, pâ¯=â¯0.006) and stage 4 disease (56% vs 41%, pâ¯=â¯0.002). Signet ring adenocarcinoma comprised 45% of cases in the pediatric group as compared to 20% of cases in the adults (Pâ¯<â¯0.001). Similar proportions in both groups underwent surgery. However, near-total gastrectomy was more common in the pediatric group (16% vs 6%, pâ¯<â¯0.001). The proportions of patients with negative margins, nodal examination, and presence of positive nodes were similar. There was no overall survival difference between the two age groups (HR 0.92, 95% Confidence interval 0.73-1.15). CONCLUSION: While gastric adenocarcinoma in pediatric patients present with a more advanced stage and poorly differentiated tumors compared to adults, survival appears to be comparable. TYPE OF STUDY: Retrospective cohort study. LEVEL OF EVIDENCE: III.