The impact of primary pancreatic tumor location on clinical outcomes in advanced disease: Results from the chord consortium.

e19267 Background: Pancreatic cancer is the fourth leading cause of cancer-related death with an average life expectancy of approximately six months following diagnosis. It is essential to understand the behavior of cancer cells to predict pattern of progression. Previous studies have shown that location of pancreatic adenocarcinoma has an influence on overall survival (OS) with worse OS among patient whom developed pancreatic cancer in the tail of pancreas. The objective of this study was to determine if location of the primary pancreatic adenocarcinoma (head/neck vs. body vs. tail) has an influence on overall survival and study pattern of metastasis to lung, liver and peritoneum base on primary tumor site. Methods: A retrospective cohort design was used to identify cases of advanced adenocarcinoma pancreas and to assess disease and treatment-related characteristics. Medical records from all adult patients diagnosed with metastatic pancreatic cancer across five Canadian academic cancer centers in Canada from 2014 to 2019 were reviewed using a national Research Electronic Data Capture (REDCap) database. Prognostic variables including age, Charlson comorbidity index, ECOG, cigarette smoking, nodal status, sites of metastases, and type of first line chemotherapy were collected. Cox proportional hazards model was used to examine the association between anatomical location of pancreatic cancer and survival, adjusted for measured confounders. Analyses were completed using SAS, where alpha of 0.05 was defined as the level of significance. Results: A total of 1161 participants were included in the study. The primary origin of pancreatic cancer included head/neck (51.8%), tail (20%) and body (16%). Metastatic sites included peritoneum (n = 170), lung (n = 145), and liver (n = 563). Peritoneal metastasis originated from tail (21.3%) and body (16.8%) and less from head /neck (9.1%) (P < 0.001). Liver metastasis originated from body (52.7%) and tail (66%) and less from head/neck (37%) (P < 0.001). Lung metastasis originated from body (13.6%) and tail (19.6%) and less from head/neck (7.8%) (p < 0.001). Multivariate analyses (MVA) showed that primary tumour location was not associated with overall survival (p > 0.05). Conclusions: Pancreatic lesions that originate in the body and tail were more likely to metastasize to lung, liver and peritoneum. Anatomical location of the primary pancreatic cancer was not associated with overall survival.