Intraluminal washout in rectal and sigmoid colon cancer surgeries with double-stapling technique anastomosis: A single-institution prospective study

Aim: This study aimed to determine the necessity of intraluminal washout through cytological assessment to prevent implantation of exfoliated cancer cells (ECCs) in patients with rectal and sigmoid cancers.

Methods: We studied 140 patients with either sigmoid or rectal cancer who underwent anastomosis surgery using a double-stapling technique. An intraluminal washout sample was collected before and after irrigation with 1000, 1500, or 2000 mL of physiological saline or distilled water. Cytological assessments were conducted using the Papanicolaou classification system, where classes IV and V indicated positive cytological findings.

Results: Initially, 46.4% of the patients (65 out of 140) had positive ECCs. Patients with cancer cells had a significantly shorter distal free margin (DM) from the tumor (p < 0.001). The length of the DM was significantly associated with the tumor distance from the anal verge (p < 0.001). After irrigation with 2000 mL, ECCs were found in only 7.3% of patients. Logistic regression analysis showed that DM (≤50 mm) and tumor size (≥50 mm) were independent risk factors for positive ECCs after intraluminal washout, regardless of the type of irrigation solution used.

Conclusion: In patients with sigmoid colon cancer, adequate preoperative bowel preparation, a long DM, and a small tumor size, a 1000 mL intraluminal washout may be sufficient. By contrast, in patients with rectal cancer with a short DM and a large tumor size, a ≥2000 mL intraluminal washout is required. The different types of irrigation solution did not affect the ECCs. Large randomized controlled trials are required to confirm these results.