Extent of intraluminal exfoliated malignant cells during surgery for colon cancer: Differences in cell abundance ratio between laparoscopic and open surgery

INTRODUCTION: Laparoscopic colectomy with intracorporeal anastomosis is a minimally invasive surgical procedure for patients with colon cancer. However, there are often concerns about the presence of intraluminal exfoliated malignant cells in the intracorporeal anastomosis. This study investigated the relationship between colon cancer surgery and the incidence of intraluminal exfoliated malignant cells and several factors. METHODS: Eighty-nine consecutive patients who underwent either laparoscopic or open colectomy were prospectively studied in our department between 2007 and 2011. Before anastomosis, the proximal and distal lumens were irrigated with normal saline and subjected to cytological examination. RESULTS: In 27 patients (30.3%), exfoliated cancer cells were detected. On the distal side, the frequency of positive cytology findings of exfoliated malignant cells was significantly lower in the laparoscopic colectomy group than in the open colectomy group (P = 0.01). In the laparoscopic colectomy group, there were no cases of positive cytology findings for exfoliated malignant cells more than 100 mm from the primary tumor. The incidence of positive cytology more than 100 mm from the primary tumor was significantly lower than the incidence of positive cytology less than 100 mm from the primary tumor (P = 0.04). CONCLUSIONS: Exfoliated malignant cells were detected at anastomosis sites in patients with colon cancer. On the distal side, laparoscopic colectomy may prevent the development of exfoliated malignant cells.