Circulating cytokeratin-positive cells and tumor budding in colorectal cancer.

AIM

To investigate whether circulating cytokeratin-positive (CK) cells in the mesenteric blood of resected colorectal specimens are prognostic and correlate with tumor budding.

METHODS

Fifty-six colorectal specimens were collected between 9/2007 and 7/2008. Blood from the mesenteric vein was drawn immediately after receiving the fresh and unfixed specimens in the pathology department. After separation of the mononuclear cells by Ficoll-Hypaque density-gradient centrifugation, cytological smears were immunocytochemically stained for CK18. Tumor budding was evaluated on slides stained for pan-cytokeratin. The identification of ≥ 30 buds/1.3 mm was defined as high grade budding.

RESULTS

CK cells and clusters were identified in 29 (48%) and 14 (25%) of the samples, respectively. Two cells were identified in one of three non-malignant cases. Clusters were found exclusively in malignant cases. The occurrence of CK cells or clusters was not associated with any of the evaluated clinicopathological factors, including surgical technique and tumor budding. Moreover, the occurrence of CK cells or clusters had no influence on the cancer-specific survival [75 mo (CI: 61; 88) 83 mo (CI: 72; 95) and 80 mo (CI: 63; 98) 79 mo (CI: 69; 89), respectively].

CONCLUSION

CK cells and showed neither prognostic significance nor an association with tumor budding. It is very likely that CK18-staining is not specific enough to identify the relevant cells.