Influence of lavage timing on tumor cell burden during colonic resection

A subset of patients undergoing elective resection for an intra-abdominal malignancy may have viable tumor cells present within the peritoneal cavity at the start of the procedure. The presence of these cells may alter the pattern of tumor recurrence.

Six million human colorectal tumor cells were radiolabeled and injected into the pelvis of eight pigs before the undertaking of a standardized laparoscopic-assisted sigmoid colectomy. In four pigs, a 1-liter saline lavage was performed before resection, and in the four remaining pigs, a similar lavage was performed after construction of the anastomosis. After completion of the sigmoid colectomy, pigs were killed, and the anastomosis was excised. Counting the radioactivity present on each sample and correlating this with the radioactivity present within the initial cell inoculum enabled the number of cells on each anastomosis to be calculated. Additional measurements were made of the number of cells on the resected bowel specimen, the stapling device, the resected anastomotic donuts, the trocars and abdominal wounds, and the lavage fluid.

Significantly fewer cells were detected on the anastomosis, the resected bowel specimen, and the donut of resected tissue in the pigs that received a preresection lavage (P = 0.01). Significantly greater numbers of cells were retrieved in the lavage fluid in this group (P = 0.01). No differences were detected in the number of cells that contaminated the stapling device (P = 0.1), trocars (P = 0.47), or trocar sites (P = 0.27).

The simple strategy of lavage at the commencement of resection for an intra-abdominal resection may reduce contamination of the anastomosis and effect a reduction of the total number of viable cells present within the abdominal cavity in patients with free intra-abdominal tumor cells.