Decreased incidence of isolated tumor cells in lymph nodes after laparoscopic resection for colorectal cancer.

Background: Laparoscopic surgery has potential for less tumor cell spread because of the no-touch technique. We assessed the effect of the surgical approach (open versus no-touch laparoscopic) on the presence of tumor cells in sentinel lymph nodes (SN) of patients with stage I and II colorectal cancer.

Methods: A single-center consecutive prospective series of patients operated on for colorectal cancer was analyzed. After conventional hematoxylin and eosin (H&E) staining, 107 patients without lymphatic metastases were included; 59 patients had open surgery, and 48 patients underwent laparoscopic resection. Patients in the laparoscopic group underwent a no-touch medial to lateral approach, whereas the conventional lateral to medial approach was applied in open surgery. A SN procedure was performed in all patients. The SNs were immunohistochemically analyzed for presence of occult tumor cells (OTC). According to the American Joint Committee on Cancer (AJCC) these tumor cells were divided into micrometastases (0.2-2 mm) or isolated tumor cells (ITC, < 0.2 mm).

Results: In ten patients micrometastases were found, equally distributed between the two groups. However, ITC were more often found after open surgery (18 versus 5 patients, p = 0.03). Presence of OTC was related to depth of tumor invasion and tumor diameter > 3.5 cm. Logistic regression analysis identified lymphovascular invasion as a predictor for micrometastases [odds ratio (OR) 18.4], whereas open resection was predictive for presence of ITC (OR 3.3).

Conclusions: No-touch medial to lateral laparoscopic surgery results in less isolated tumor cells in lymph nodes compared with open lateral to medial surgery in patients with stage I and II colorectal cancer.