Background: Ductal pancreatic adenocarcinoma (PDAC) still has a dismal prognosis even when deemed resectable. A cancer free resection margin (R0) is associated with a more favourable prognosis than the presence of tumour cells at resection margin (R1). However, the precise definition of the R0 status is still a matter of debate in PDAC. For a more accurate determination of R0 in PDAC the concept of circumferential resection margins (CRM) has been introduced. However, an international standardized nomenclature of CRM is still missing, and the clinical value of the CRM concept is not yet fully established. Here we evaluate whether the CRM status as defined in the national German S3 guideline is an independent prognostic factor in PDAC using data from the regional cancer registry of the State of Baden Württemberg in Germany. Methods: Data from the cancer registry of the State of Baden-Württemberg, Germany were collected, using documented patients diagnosed with invasive ductal adenocarcinoma of the pancreas between 2015 and 2020. The R-status was assessed according to the national German S3 guideline with R0 wide/CRM- when CRM is > 1mm, R0 narrow/CRM+ when CRM is £ 1 mm from the tumour and R1 when tumour cells are found at the resection margin. Progression free survival (PFS) as well as 3-year overall survival (OS) were assessed using Kaplan-Meier statistics and multivariable Cox regression models (adjusted for age, pN stage, primary tumor location and systemic treatment). Results: In total we identified 1098 cases surgically treated for pancreatic cancer and fulfilling the inclusion criteria. 340 patients had an R0 wide/CRM- resection, 410 patients an R0 narrow/CRM+ resection, and 348 patients an R1 resection. The R0 wide/CRM- status was associated with a significantly increased median 3-year OS rate compared to the other two groups (51,5%, 37,4% and 26,7% for R0 wide/CRM-, R0 narrow/CRM+ and R1, respectively). mPFS was also longer in the R0 wide/CRM- group. These findings were robust with regards to grading. 5-FU based adjuvant treatment was mainly mFOLFIRINOX and show better outcome as compared to gemcitabine-based treatments. Conclusions: The present study was performed using real world data reflecting actual clinical settings. The results obtained are in good agreement with data from clinical trials, including the prognostic role of the R- and N- Status as well as the efficacy of adjuvant chemotherapy protocols used.