Purpose: The aim was to investigate the significance of lymph node micrometastases in Dukes Stages A and B colorectal cancer.
Methods: Archival specimens were examined from 147 patients (96 colon, 51 rectum; 44 Stage A, 103 Stage B) who had surgery between 1987 and 1994. One lymph node section from each node (colon, 1-11; median, 4; rectum, 1-15; median, 3) was examined with use of an anticytokeratin antibody.
Results: Forty-seven (32 percent) patients had micrometastases. At follow-up in June 1996, 23 patients had died of cancer or with known tumor relapse, after a median time of 28 (range, 5-67) months; 8 of 47 (17 percent) patients had micrometastases, 15 of 100 (15 percent) did not. No statistically significant differences were observed according to micrometastases when the results were analyzed with respect to Dukes stage or survival time. The median survival time of living patients with micrometastases was 48 (range, 18-97) months, and for patients without micrometastases, 48 (range, 19-111) months. Six of 96 living patients had a tumor relapse; three of these displayed micrometastases.
Conclusion: Lymph node micrometastases are not a useful prognostic marker in Dukes Stages A and B and do not imply different strategies for additional therapy or follow-up.