Oxidative stress markers in laparoscopic versus open colectomy for cancer: a double-blind randomized study

Colorectal cancer as well as colorectal surgery is associated with increased oxidative stress through different mechanisms. In this study the levels of different oxidative stress markers were comparatively assessed in patients who underwent laparoscopic or conventional resection for colorectal cancer. Sixty patients with colorectal cancer were randomly assigned to undergo laparoscopic (LS) or open surgery (OS). Lipid, protein, RNA, and nitrogen damage was investigated by measuring serum 8-isoprostanes (8-epiPGF(2 alpha)), protein carbonyls (PC), 8-hydroxyguanosine (8-OHG), and 3-nitrotyrosine (3-NT), respectively. The primary end point of the study was to analyze and compare serum levels of the oxidative stress markers between the groups. Postoperative serum levels of 8-epiPGF(2 alpha), 3-NT, and 8-OHG were significantly lower in the LS group at 24 h after surgery (p < 0.05). At 6 h postoperatively, the levels of 8-epiPGF(2 alpha) and 3-NT were significantly lower in the LS group (p < 0.05). No difference in the levels of PC was found between the two groups at any time point. In the OS group, postoperative levels of 8-epiPGF(2 alpha) were significantly lower than the preoperative values (p < 0.01). In the LS group, the postoperative values of 8-epiPGF(2 alpha), 3-NT, and 8-OHG were significantly lower than the preoperative values (p < 0.05). Laparoscopic surgery for colorectal cancer is associated with lower oxidative stress compared to open surgery. 8-epiPGF(2 alpha) was the most suitable marker for readily defining the oxidative status in patients who underwent surgery for colorectal cancer.