Treatment of localized pancreatic cancer Towards innovative and personalized treatment strategies

The first part of this thesis addresses the optimization of the interpretation and applicability of tumor markers carbohydrate antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) in various stages of localized pancreatic ductal adenocarcinoma (PDAC). We concluded that regardless the baseline level of CA19-9, neoadjuvant therapy has a better overall survival (OS) compared to upfront surgery. The second chapter describes that among patients with locally advanced PDAC, the optimal response of CA19-9 is a decline of 60% following induction chemotherapy. For patients that have non-elevated CA19-9 at baseline, the third chapter describes that elevated CEA at baseline and at restaging was associated with worse OS compared to normal values.
The second part describes the findings of on the impact of intra-operative ultrasonography (IOUS) during surgical exploration of localized PDAC. Following assessment with IOUS in 85 patients, the resectability status changed in 38% of patients, predominantly based on a decrease in arterial involvement.
The third part of this thesis consists of three chapters that explored the optimal applicability of stereotactic ablative radiation therapy (SABR) in the treatment of localized pancreatic cancer. We found predictive factors for better OS following treatment with SABR, these may potentially enhance patient selection for SABR. Furthermore a systematic review described that SABR can be safely applied as a single therapy in patients with primary localized. The ongoing PANCOSAR trial investigates the impact of SABR as single treatment on survival and quality of life in patients with localized PDAC whom would otherwise be treated with best supportive care.