Important prognostic histological parameters for patients with invasive ductal carcinoma of the pancreas.

For clinicians, the orthodox histological investigation of patients with invasive ductal carcinoma (IDC) remains important for predicting prognoses. The purpose of the present study was to determine the most important of the known prognostic histological parameters (including fibrotic focus and tumor necrosis), enabling the outcomes of 101 patients with IDC of the pancreas to be predicted accurately. Furthermore, we established a scoring classification consisting of important prognostic histological parameters examined in this study. Multivariate survival analyses showed that invasive tumor size of more than 3 cm, the presence of tumor necrosis, the presence of nerve plexus invasion and lymph vessel invasion scores of 2 or 3 were important prognostic factors. Our scoring classification, consisting of the above four parameters, accurately classified the outcome of patients independent of the invasive tumor size of IDC. We concluded that invasive tumor size of 3 cm or more, the presence of tumor necrosis, the presence of nerve plexus invasion and lymph vessel invasion scores of 2 or 3 are important histological prognostic parameters for patients with IDC of the pancreas. Furthermore, the scoring system consisting of the above four histological parameters is probably a very useful prognostic histological classification for patients with IDC of the pancreas. (Cancer Sci 2005; 96: 858 - 865).