The impact of laparoscopic biopsy of pancreatic lymph nodes with helium and carbon dioxide on port site and liver metastasis in BOP-induced pancreatic cancer in hamster

Abstract

The influence of pancreatic biopsy during laparoscopy with carbon dioxide (CO2) and helium on the incidence of port site and liver metastasis in pancreatic carcinoma is still unknown. Ductal adenocarcinoma of the pancreas was induced in Syrian hamsters (n = 30) by injection of N-nitrosobis-2-oxopropylamin (BOP, 10 mg/kg body weight/week) for 12 weeks. In week 13, hamsters were randomized in 3 groups (n = 10): While in group 1 (gr. 1) a laparotomy and biopsy of pancreatic lymph nodes was performed, gr. 2 and gr. 3 underwent a laparoscopic biopsy either with CO2 or helium. Therefore, one trocar was located in the left (biopsy) and the right abdominal wall (camera). In the 18th week all animals were sacrificed and the incidence of abdominal wall, port site and liver metastases was histologically determined. While there were abdominal wall metastases after laparotomy in 10% (n = 1), we observed trocar metastases in the CO2 group in 20% (n = 2). However, there were no trocar metastases in the helium group. The incidence of liver metastasis did not differ between the laparotomy and the helium group (20% vs 30%), but was increased in the CO2 group (60%). Laparoscopic biopsy of pancreatic lymph nodes with CO2 increased the incidence of port site and liver metastases in pancreatic cancer. The helium group was equal to the laparotomy group in this respect. Thus, staging laparoscopy with helium might become an alternative to explorative laparotomy in pancreatic cancer.