Objectives Prognosis for locally advanced esophagogastric adenocarcinoma (EAC) is poor with surgery alone and adjuvant therapy after open esophagectomy is frequently not tolerated. with stage II or higher EAC treated with MIE (n=375) were identified. Using 30 pretreatment covariates propensity for assignment to either neoadjuvant followed by MIE (n=183; 54%) or MIE as primary therapy (n=156; 46%) was calculated generating 97 closely-matched pairs. Hazard ratios were adjusted for age sex BMI smoking comorbidity and final pathologic stage. Results In propensity-matched pairs adjusted hazard ratio for death did not differ significantly for primary MIE compared to neoadjuvant (HR NSC 405020 0.83; 95% CI 0.60-1.16). Recurrence patterns were similar between groups and 65% of patients with IIb or greater pathologic stage received adjuvant therapy. Clinical staging was inaccurate in 37/105 (35%) patients who underwent primary MIE (n=18 upstaged and n=19 downstaged). Conclusions Primary MIE followed by adjuvant chemotherapy guided by pathologic findings did not negatively impact survival and allowed for accurate staging of the patient compared to clinical NSC 405020 staging. Our data suggest that primary MIE in patients with resectable EAC may be a reasonable approach improving stage-based prognostication and potentially minimizing overtreatment in patients with early-stage disease through accurate stage assignments. A randomized controlled trial testing this hypothesis is needed. control patients ([E?] neoadjuvant therapy followed by MIE) still in the matching pool whose propensity scores were within 0.05 of the exposure patient��s score. If a suitable match was not available the patient was not included in the matched dataset. Matching was repeated several times with different random number generator seeds to ensure that matching balance and final outcome analysis produced similar stable results each time regardless of random seed. (Data not shown) Prior NSC 405020 to propensity matching neoadjuvant patients were significantly younger and more likely to have daily alcohol use and pretreatment complaints of dysphagia while primary MIE patients had higher age-adjusted Charlson Comorbidity Index (CCI; p=0.025) scores.(26) At least one comorbid condition was present in 56% of patients (range 1-6; n=190/339) and 2 or more in 22% (n=74/339). EUS showing pretreatment invasion into the muscularis propria (T2) was more common in the primary MIE patients; they were also less likely to have adventitial (T3) invasion. Pretreatment clinical stage III/Iva was more common in the neoadjuvant cohort but there were no CD180 differences in pretreatment nodal metastasis rates tumor location or grade. (Table 2) Ninety-seven closely matched pairs (n=194) were generated using Stata.(27) Prior to matching overall mean % bias was 15.2% (p-value<0.001 for differences between the cohorts). After matching overall mean % bias was 6% (p-value=0.973) with less than 10% bias for most variables and less than 20% in all variables except history of smoking. (Table 3) Age (median 64 years for both; p=0.895) and age-adjusted CCI score (2 versus NSC 405020 1.5; p=0.2757) were similar between matched and unmatched patients; median survival was 20.3 versus 23.65 months (p=0.1094) and recurrence rates were 58% versus 53% (p=0.377) respectively. The c-index for the propensity matching was 0.778 indicating very good discrimination. Table 3 Comparison of clinical variables between groups after propensity score assignment and after propensity-matching Statistical analysis Statistical analysis was performed using STATA 13 (27) summarizing descriptive statistics with frequencies and percentages for categorical variables and median with interquartile range (IQR) for continuous variables. Variables associated with adjuvant therapy were assessed using logistic regression. Data missingness was random. Survival time was defined as time from esophagectomy to date of last living contact or death. Time to recurrence was defined as time from esophagectomy to last clinical evaluation for recurrence. Survival curves for matched cohorts were compared using log-rank test for equality of survivor functions. Hazard ratios for death were calculated using stratified (matched) Cox proportional hazards regression with clustered.