Circulating Tumor Cells in Patients Undergoing Resection of Colorectal Cancer Liver Metastases. Clinical Utility for Long-Term Outcome: A Prospective Trial.

BACKGROUND

Patients with resected colorectal cancer liver metastases display heterogeneous clinical behavior. The identification of new prognostic factors would help in making more accurate decisions.

OBJECTIVE

The aim of this study was to evaluate the survival impact of circulating tumor cells (CTCs) in this setting.

METHODS

We conducted a prospective study of patients with resected liver metastases of colorectal cancer. Patients were included in the study from February 2009 to January 2013. The CellSearch System™ was employed for the detection of pre- and postsurgery CTCs. A positive test was defined as two or more CTCs/7.5 mL of blood. Recurrence rate, disease-free survival, and overall survival were calculated, and univariate and multivariate analyses were performed.

RESULTS

Forty-four patients were included in our study. After a median follow-up of 60 months (range 28-74), 32 patients experienced recurrence (72.7%). The CTCs number was determined and the test was positive in 8 patients (18.6%) before surgery and 13 patients (29.5%) after surgery. The postoperative detection of CTCs was not related to any clinical outcome; however, the preoperative detection of CTCs was significantly related to behavior. All patients in the preoperative CTC-positive group relapsed, versus 65% in the CTC-negative group (p = 0.051). Disease-free survival was 19 months in the preoperative CTC-negative group versus 7 months in the CTC-positive group (p = 0.01). Additionally, overall survival was 69 months in the preoperative CTC-negative group versus 17 months in the CTC-positive group (p = 0.004). Preoperative CTC count remained significant in multivariate analysis.

CONCLUSIONS

In this cohort of colorectal cancer liver metastases patients, the presence of two or more preoperative CTCs was associated with disease progression and poor survival despite complete resection.