Background: Minimal residual disease in patients with pancreatic cancer is defined as the presence of isolated tumor cells in the patient's body, in which the primary tumor was removed and is currently without clinical signs of disease. These isolated tumor cells may be described as precursors of micrometastases. Assessment of MRD in patients with this highly malignant disease could eliminate burdensome implementation of surgery in patients with systematic dissemination of molecular disease and provide a more precise prognosis. METHODS AND RESULTS; The study to date included 70 patients operated on with curative intent for carcinoma of the pancreas. Samples of peripheral and portal blood, bone marrow, peritoneal lavage and of the tumor itself were analyzed by real-time PCR which measured the expression of hTERT (telomerase), EGFR1 (receptor for epidermal growth factor) and CEA (carcinoembryonic antigen). The expression of these markers was correlated with clinicopathological characteristics and survival parameters. We found a statistically significant association between EGFR expression levels in the portal blood and clinical stage--patients with advanced disease have a higher expression of EGFR in the portal stream and peritoneal lavage in contrast to patients without the presence of metastases.
Conclusions: The results of this pilot study demonstrated a high sensitivity and specificity of the RT-PCR method for detecting circulating tumor cells in patients with pancreatic cancer. By utilizing this methodology, we are able to provide prognostic value of minimal residual disease and its significance for the indication of radical surgery for pancreatic cancer.