The detection of cytokeratins in lymph nodes of Duke's B colorectal cancersubjects predicts a poor outcome

Objectives The objectives of this study were to examine the frequency of ly mph node micrometastases detected by keratin immunohistochemistry and their relationship with survival behaviour. Methods A total of 133 consecutive patients staged as Duke's B, who had cur ative resection for colorectal cancer (CRC), comprised the study population . Patients who had died of a non-CRC-related cause or who became lost to fo llow-up were excluded, resulting in an amended population of 100. Study end -points were defined as disease-free survival of 5 years or CRC-related dea th. Paraffin-embedded lymph node sections were stained with a commercial cy tokeratin antibody using a standard avidin-biotin technique. Results One quarter of subjects had micrometastases. Fifty-six per cent of subjects with positive lymph nodes had an adverse outcome, compared with 11 % of subjects with negative nodes. A highly significant association was fou nd between lymph node cytokeratin expression and mortality in both the univ ariate (log rank P = 0.0001) and multivariate (Cox proportional hazards P = 0.0123) analysis. Conclusions Lymph node micrometastases detected by this inexpensive and sim ple technique are significantly associated with mortality in Duke's B CRC. This technique may be used to select patients for adjuvant chemotherapy. (C ) 2000 Lippincott Williams & Wilkins.