p53 Overexpression in lymph node metastases predicts clinical outcome in ductal pancreatic cancer

In this study, we evaluated the prognostic significance of both p53 overexpression and proliferating activity in 133 primary ductal pancreatic carcinomas and in their regional synchronous lymph node metastases by immunohistochemistry, by using DO7 and MIB1 monoclonal antibodies, respectively. Tumor samples and lymph nodes were obtained from formalin-fixed, paraffin-embedded archival material of patients operated on between 1976 and 1996. Patients had a well-documented clinical history and were given accurate follow-up. p53 accumulation was observed in 77 (54%) of 133 primary tumors and in 22 (44%) of 50 patients with nodal metastases. The p53 overexpression was directly related to proliferating activity (p = 0.01) in the primary tumors. A significant direct correlation was present between the p53 expression in the primary tumor and in nodal metastases (p = 0.01); the same occurred for proliferating activity by MIB1 (p = 0.002). The patients' overall survival was affected by the presence of nodal (p = 0.02) and distant (p = 0.0001) metastases. The p53 immunoreactivity in nodal metastases was associated with a statistically significant decrease in the postoperative survival period (p = 0.005). Multivariate analysis confirmed these results, and the only two parameters that maintained statistical significance were MI status (p = 0.0006) and p53 overexpression in nodal metastases (p = 0.01).