Background The impact of socioeconomic status (SES) has been described for screening and accessing treatment for colon cancer. However, little is known about the “downstream” effect in patients who receive guideline‐concordant treatment. This study assessed the impact of SES on cancer‐specific survival (CSS) and overall survival (OS) for stage III colon cancer patients. Methods The SEER Census Tract‐Level SES Dataset from 2004 to 2015 was used to identify stage III colon adenocarcinoma patients who received curative‐intent surgery and adjuvant chemotherapy. The predictor variable was census tract SES. SES was analyzed as quintiles. The outcome variables were OR and CSS. Statistical analysis included chi square tests for association, Kaplan–Meier, Cox, Fine and Gray regression for survival analysis. Results In total, 27,222 patients met inclusion criteria. Lower SES was associated with younger age, Black or Hispanic race/ethnicity, Medicaid/uninsured, higher T stage, and lower grade tumors. CSS at the 25th percentile was 54 months for the lowest SES quintile and 80 for the highest. Median OS was 113 months for the lowest SES quintile and not reached for highest. The 5‐year CSS rate was 72.4% for the lowest SES quintile compared to 78.9% in the highest ( p < 0.001). The 5‐year OS rate was 66.5% for the lowest SES quintile and 74.6% in the highest ( p < 0.001). Conclusion This is the first study to evaluate CSS and OS in an incidence‐based cohort of stage III colon cancer patients using a granular, standardized measure of SES. Despite receipt of guideline‐based treatment, SES was associated with disparities in CSS and OS.

7032 Background: Socioeconomic status (SES) has been associated with worse outcomes in stage III colon cancer. However, these studies have used large geographic areas (zip codes or counties) as a proxy for SES which may bias results. To overcome this challenge, we used a national database with census-tract level SES to assess the impact on cancer-specific (CSS) and overall survival (OS). Methods: Using the SEER Census-Tract Dataset from 2004-2015, we identified 8th edition AJCC stage III colon adenocarcinoma patients who underwent curative-intent surgery and initiated adjuvant chemotherapy. The predictor variable was census-tract level SES, consisting of 7 variables such as income, housing, and education. SES was analyzed as quartiles. Statistical analysis included chi square tests for association and Kaplan-Meier and Cox regression for survival analysis. Results: We identified 27,222 patients who met inclusion criteria. Lower SES was associated with younger age, Black or Hispanic race/ethnicity, Medicaid or uninsured status, higher T stage, <12 lymph nodes examined and lower grade tumors. Median CSS was not reached; the 25th percentile CSS time was 54 months for the lowest SES (LSES) quartile and 80 months for the highest (HSES). Median OS was 113 months for LSES and not reached for HSES. The 5-year CSS rate was 72.4% for the LSES quartile compared to 78.9% in the HSES (p<0.001). The 5-year OS rate was 66.5% for LSES and 74.6% in the HSES (p<0.001). After adjusting for potential confounders (age, sex, race, insurance, pathologic T and N stage and grade), LSES was associated with increased cancer-specific death relative to the HSES (HR 1.22; 95% CI [1.114-1.327]) Conclusions: This is the first study to evaluate CSS and OS in a national cohort of stage III colon cancer patients using a granular, standardized measure of SES. Despite receipt of guideline-based treatment, low SES remained a predictor of increased cancer-specific mortality. These data suggest that investigating treatment barriers beyond adjuvant therapy is needed to address colon cancer survival disparities. [Table: see text]

e16781 Background: Borderline resectable pancreatic ductal adenocarcinoma (BR PDAC) is a subset of pancreatic cancer with unique prognostic implications. A multimodality, neoadjuvant therapy (NAT) approach has known benefits such as downstaging tumors, reducing the risk of a positive margin, and treating micrometastatic disease. Patient selection and therapy sequencing are controversial owing to the high risk of recurrence. Therefore, we aimed to identify factors predicting recurrence and overall survival (OS) in BR PDAC patients undergoing NAT. Methods: We identified BR PDAC patients treated with NAT followed by surgery at Moffitt Cancer Center between 2008-2015. We evaluated clinical, demographic, and perioperative factors to identify predictors of recurrence and OS. Statistical analyses were performed with univariate and multivariable Cox regression models. Results: 117 patients with BR PDAC who received NAT were evaluated; 53 (45%) were female and 64 (55%) were male. Of those, 91 (78%) received gemcitabine/xeloda/taxotere and the remainder received other gemcitabine or 5FU regimens. 107 (91%) patients received neoadjuvant radiation, mainly 5-day dose painted SBRT. Post- NAT CA 19-9 normalized in 39 (33%) and 11 (9%) additional patients normalized after surgery. Pathologic treatment effect was appreciated in 85 (73%) patients and pathologic complete response (pCR) was seen in 18 (15%). 95 (81%) patients initiated adjuvant therapy. In multivariable analysis, the strongest predictor of recurrence was higher log(10) post-operative CA 19-9 (HR 2.29; 95% CI, 1.40-3.75). Time from initiation of NAT to surgery ≥ 5 months also predicted recurrence (HR 2.08; 95% CI, 1.16-3.72). In OS analysis, 71 patients had recurrence after multimodality treatment; 61 (86%) died and 10 (14%) were alive. In multivariable analysis, the strongest predictors of prolonged OS from recurrence were female gender (HR 0.47; 95% CI, 0.26-0.84) and presence of a treatment effect (HR 0.37; 95% CI, 0.15-0.93). Conclusions: We observed treatment effects and pCR comparable to other institutions, supporting a multimodality approach to BR PDAC. Higher post-operative CA 19-9 and time to surgery ≥ 5 months from initiation of NAT were associated with an increased risk of recurrence. These data suggest that timely receipt of surgery after completion of NAT may impact recurrence and OS in BR PDAC.

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