Isolated tumor cells in lymph nodes are not a prognostic marker for patients with stage I and stage II colorectal cancer

Background and Objectives: Lymph node metastasis is an important prognostic factor for colorectal cancer (CRC). The relationship between isolated tumor cells (ITC) in lymph nodes and the prognosis is controversial. The aim of this study is to evaluate the prognostic importance of ITC in lymph nodes from patients with stage I and II CRC. Methods: We examined all the lymph nodes obtained during surgery from 121 consecutive patients with stage I and II CRC after a curative resection in 1999 by using monoclonal antibody against cytokeratin (MNF116). Clinicopathologic data and follow-up information were obtained from all patients. The mean follow up duration was 57 months. Results: ITC were found in 50% (60/121) of the patients. The mean number of examined lymph node was 19.3 ± 9.4. The presence of ITC was not related to clinicopathologic factors such as age, sex, location of tumor, tumor size, tumor depth, differentiation, lymphovascular invasion, and the preoperative CEA level, except for the tumor gross type (P = 0.002). There were no statistically significant differences for the recurrence rate (10/60 = 16.7% and 9/61 = 14.8%, respectively), and disease-free survival (P = 0.809) between the ITC positive group and ITC negative group. Conclusions: The presence of ITC detected by immunohistochemical staining does not have an influence on the prognosis of patients with stage I and II CRC.