Influence of colorectal laparoscopic surgery on dissemination and seeding of tumor cells

Background: This study aimed to compare the influence of colorectal laparoscopic surgery and conventional surgery on dissemination and seeding of tumor cells. Methods: Intraoperative peritoneal lavage cytology was performed for 36 patients with colorectal cancer during colorectal laparoscopic surgery and for 45 patients with colorectal cancer during conventional surgery. Cytology was examined twice: immediately after opening of the peritoneal cavity and just before closure of the abdomen. Saline was poured into the peritoneal cavity, and 100 ml fluid was retrieved after irrigation. Laparoscopic instruments were lavaged after surgery with 100 ml of saline. Carbon dioxide (CO2) was derived through the trocar side orifice after pneumoperitoneum during laparoscopic coloectomy and filtered through 100 ml of saline. Cytologic examination of the filtrate was performed after the filtration process, smear, cell block, and staining. Results: Malignant cells were not detected in the CO2 filtrate gas. The incidence of positive cytology in the lavage of the instruments during laparoscopic surgery was 2.78%. The incidence of positive cytology during laparoscopic surgery was 33.33% in the prelavage and 8.33% in the postlavage. The incidence of positive cytology during conventional surgery was 33.33% in the prelavage and 11.11% in the postlavage. Conclusion: During colorectal laparoscopic surgery, CO2 pneumoperitoneum does not affect tumor cell dissemination and seeding. In this study, laparoscopic techniques used in colorectal cancer surgery were not associated with a greater risk for intraperitoneal dissemination of cancer cells than the conventional technique.