Detection of lymph nodes micrometastases in Dukes' A and B colorectal cancer using anti-cytokeratin antibodies AE1/AE3.

AIM

To detect lymph nodes micrometastases and analyze its correlation with clinicopathological parameters in Dukes' A and B colorectal cancer patients.

METHODS

One hundred and fourteen patients with colorectal cancer (Dukes' A 16; Dukes' B 98) undergoing curative operation without histological lymph nodes metastases were studied between 2001 and 2003. A total of 2,481 lymph nodes were analyzed using monoclonal cytokeratin antibody AE1/AE3 (DAKO, Carpinteria, CA) for immunohistochemistry.

RESULTS

In total, 33 (29%) patients were positive for cancer cell by immunohistochemistry. In 31 (94%) patients of them positive nodes showed single tumor cell or small groups of tumor cells; and tumor deposits measuring 0.2 and 0.37 mm in diameter in another 2 (6%) patients. Micrometastases were mainly located in the subcapsular sinus or paracortical sinus. There was no correlation between the positive lymph nodes and gender, age, tumor site, tumor size, histological type, histological grade, invasion depth, Dukes' staging and microsatellite instability (P>0.05).

CONCLUSION

Our findings suggest that immunohistochemical technique using monoclonal cytokeratin antibody AE1/AE3 may be a sensitive and reliable method for detecting lymph nodes micrometastases in Dukes' A and B colorectal cancer. The clinical significance of lymph nodes micrometastases is still not confirmed.