Cytomorphology of Circulating Tumor Cells and Cell Clusters in Chilean Patients with Colo-Rectal Cancer

the aim of this study was to determine the cytomorphological characteristics of circulating tumor cells (ctcs) in patients with colo-rectal cancer and compare them with the primary tumor and metastasis. ctcs were obtained from blood using differential gel centrifugation and detected using standard immunocytochemistry using anti-cea. primary ctcs were defined as those detected before surgery and secondary ctcs those detected after. surgical specimens of the primary tumor and metastasis were evaluated using standard histological methods with hematoxillin and eosin. ctcs both primary and secondary retained the cytomorphological characteristics of the primary tumor, showing marked intra-patient pleomorphism. there were no differences between primary and secondary ctcs in their cytomorphological features. ctcs from patients with signet ring tumors showed the presence of intracellular mucin deposits. groups of 3 or more ctcs were only seen in patients with metastasis, whereas duplets of ctcs were seen in patients with metastatic and non-metastatic colo-rectal cancer. this study provides an initial analysis of the cytomorphological features of ctcs, providing a foundation for further investigation into the significance and metastatic potential of ctcs.