Background: To improve the surgical outcome after resection of pancreatic adenocarcinomas, multimodal treatment concepts need to be applied and improved. In spite of several positive studies, and the fact that multimodality treatment is the standard concept in major centers for pancreatic cancer surgery, a recent trial shed some doubt on the positive effect of adjuvant radiochemotherapy, so that the majority with reservations about multimodal treatment feel confirmed in their opinion that surgical treatment alone is sufficient therapy for resectable pancreatic cancer. The controversy among those for and against adjuvant treatment need an up-to-date review of the indications and results achievable with various treatment modalities.
Patients/methods: The literature on the indications and results of adjuvant/neoadjuvant therapies in pancreatic cancer was reviewed to provide a solid base for current recommendations and future developments. A special view was concentrated on the biology of the disease in the spontaneous course, after surgery and during/after various palliative and adjuvant/neoadjuvant treatment modalities, to characterize the disease for an optimally targeted treatment in conjunction with surgical removal of the tumor. The results of systemic and regional chemotherapy and radiotherapy either alone or in combination, before, during, and after surgery, were critically analyzed with respect to the oncological possibilities and pitfalls of each treatment method.
Results: In two randomized trials, one testing postoperative radiochemotherapy (GITSG), and one postoperative chemotherapy (Bakkevold), the adjuvant treatment achieved a significant prolongation of the median survival time. The 5- and 10-year survival rates were improved in the GITSG study. The EORTC-GITCCG trial could not confirm the benefit of adjuvant radiochemotherapy. This study had a different design than the GITSG trial. Several historical control studies supported the beneficial effect of postoperative radiochemotherapy. In three historical control trials using regional chemotherapy, one with intraoperative radiotherapy, the survival times were improved vs. surgery alone. Intraoperative or postoperative radiotherapy as single modalities might reduce local relapses, but a survival advantage is still debated. Preoperative neoadjuvant radiochemotherapy has several advantages (downstaging, devitalizing margins and lymph node metastases, compatibility of treatment vs. postoperative radiochemotherapy), and does not seem to increase the postoperative morbidity. Several trials have confirmed the feasibility of this concept, but no survival advantage has yet been proven. Systemic and regional chemotherapy is able to downstage primarily nonresectable pancreatic cancers.
Conclusions: Postoperative adjuvant radiochemotherapy with up-to-date protocols can be recommended for routine treatment, if the surgeon or the patient desires to improve the usually remote prognosis after surgery alone. For those being undecisive or against adjuvant therapy, the participation in trials, e.g., ESPAC 1 and 2 studies, is strongly recommended. Regarding our own positive experience with adjuvant regional chemotherapy and in view of the postresectional progression pattern, we currently favour adjuvant radiochemotherapy, with the chemotherapy delivered regionally via the celiac axis. This concept will be tested vs. surgery alone in the ESPAC 2 trial. Neoadjuvant therapies have a great potential, but should be conducted within studies, such as pre-, intra-, or postoperative radiotherapy.