Surgical management of pancreatic neuroendocrine tumors

This thesis gives an overview of the surgical management and prognosis of patients with pancreatic neuroendocrine tumors (pNET).
A systematic review including 2600 studies, was performed on complications and survival after different surgical procedures for pNETs. The overall pancreatic fistula rate after enucleation was high (45%) compared to standard resections. The 5-year survival of resected pNETs without resected liver metastases was 85%.
In our own patient data, we analyzed the diagnostic value of chromogranin A and a Octreoscan. In patients with small tumors without suspicious metastases on CT scan, an additional Octreoscan is not mandatory. Chromogranin A was elevated in only 27% of patients preoperatively.
Further analysis revealed that the overall complication rate and the need for re-interventions/readmissions was not lower for enucleation compared to other resections. In addition, investigating 832 patients with different types of pancreatic pathology, a pNET was not a risk factor for the development of pancreatic fistula.
Interestingly, in our operated patients, the incidence of lymph node metastasis after pancreatoduodenectomy was high, even for small tumors.
Risk factors for recurrent disease after curative resection were identified: tumor size >2cm, positive lymph nodes and perineural invasion. Based on these risk factors we developed a nomogram to predict tumor recurrence in order to identify patients, which could benefit from adjuvant treatment and to adjust follow-up programs.
In a nationwide study on the outcome after laparoscopic or open distal pancreatectomy, we found laparoscopic distal pancreatectomy to be safe, especially after structured surgical training.