Secondary Circulating Tumor Cells (CTCs) but not Primary CTCs are Associated with the Clinico-Pathological Parameters in Chilean Patients With Colo-Rectal Cancer

Background: The aim of this study was to assess detection of circulating tumor cells (CTC) using anti-CEApre and post surgery in Chilean patients with colo-rectal cancer. Materials and
Methods: The presence of CTCswas evaluated in 80 colorectal cancer patients pre and post surgery using standard immunocytochemistry andthe results were compared with findings for standard clinico-pathological parameters.
Results: In patients presurgeryCEA (+) CTCs were frequently found, with no relation to tumor size or nodal status. After surgery, thepresence of CTCs was associated with such clinico-pathological parameters. The frequency of CTC detection innode positive patients did not change after surgery. In patients with metastasis there was also no change in thefrequency of CTC detection, and clusters of 3 or more CTCs were evident.
Conclusions: Secondary CTCs areassociated with clinico-pathological parameters only after surgical removal of the primary tumor, and mightbe important in identifying patients at high risk of relapse. Primary CTCs detected before surgical removal arefrequently found, are not associated with the clinico-pathological parameters and might have a role in cancerscreening. These findings suggest the need for studies with a larger population of patients.