[Value of cytokeratin and Ca 19-9 antigen in immunohistological detection of disseminated tumor cells in lymph nodes in pancreas carcinoma].
INTRODUCTION: Based on the fact that pancreatic carcinoma is still associated with poor outcome, the aim of the study was to determine frequency of early tumor cell dissemination using immunohistology in lymph nodes classified as tumor-free by conventional histopathology. METHODS: Fifteen patients with ductal pancreatic carcinoma and 10 patients with carcinoma of the papilla of Vater underwent radical tumor resection (resection status R0, tumor staging pTxpN0M0). In total, 229 lymph nodes classified as tumor-free by histopathology were investigated for disseminated tumor cells using antibodies against cytokeratin and CA19-9. As control, 81 lymph nodes obtained from patients with chronic pancreatitis were analyzed. RESULTS: In 55 of 229 lymph nodes (26.3%), cytokeratin-positive, disseminated tumor cells were detected. Cytokeratin-positive cells were found in at least one resected lymph node of each patient with ductal carcinoma of the pancreatic head (100%), whereas in patients with carcinoma of the papilla of Vater, no disseminated tumor cells were detected using the antibody against cytokeratin. Similarly, there was no detection of tumor cells (false-positive) in patients with chronic pancreatitis. In contrast, CA19-9 antigen was detectable in resected lymph nodes of each of the 25 carcinoma patients (pancreatic carcinoma and carcinoma of the papilla of Vater). Interestingly, 52 of 81 lymph nodes (64.2%) from the control group (chronic pancreatitis) were false-positive. CONCLUSION: Detection of disseminated tumor cells in lymph nodes using an antibody against cytokeratin is specific and suitable while use of an antibody against CA19-9 is not recommendable because of the high rate of false-positive results. The results may indicate that ductal pancreatic carcinoma generates early dissemination of tumor cells into lymph nodes. This may be one explanation for the poor outcome of this carcinoma compared with that of the carcinoma of the papilla of Vater (14 versus 48 months P < 0.05).