Lohneis P et al. - It was shown in the current study that T-lymphocyte subpopulations might be prognostic in resectable pancreatic ductal adenocarcinoma (PDAC), but further studies are warranted

Methods
Immunohistochemical stainings on tissue microarrays (TMAs) against CD3, CD8, and CD103 were performed.

Results
A high number of CD8-positive lymphocytes were independently associated with longer disease-free survival (DFS) and overall survival (OS).
Median DFS/OS were 7.4/18.1 months for patients with a low number of CD8-positive intratumoural lymphocytes and 12.7/25.2 months for patients with high numbers (HR 0.62 and 0.65, respectively).
The ratio of intraepithelial-to-total CD103-positive lymphocytes, but not the total number of CD103-positive lymphocytes or CD103-positive intraepithelial lymphocytes, was associated with improved DFS and OS in the overall study population.
The median DFS/OS was 5.9 and 15.7, respectively, for patients with a ratio of intraepithelial-to-total CD103-positive intratumoural lymphocytes greater than 0.3 and 11.6 and 24.7, respectively, for patients with a lower ratio.