Related Experiment Videos
PD-L1 expression in HNPCC-associated colorectal cancer
Naila Shiraliyeva1, Jacqueline Friedrichs1, Reinhard Buettner1
1Institute of Pathology, University of Cologne Medical School, Kerpener Str. 62, 50937, Cologne, Germany.
Background:
PD-L1 immunohistochemistry is predictive for molecular inhibitors of PD-1/PD-L1 immune checkpoint. Therefore, this study evaluated the PD-L1 expression in patients with Hereditary Non-Polyposis Colorectal Cancer (HNPCC).
Methods:
Immunohistochemical expression of PD-L1 in carcinoma cells, stromal macrophages and lymphocytes of 40 HNPCC-patients with colorectal cancer was scored semi-quantitatively.
Results:
Focal (2 cases) to extensive (2 cases) PD-L1-immunopositivity of carcinoma cells was detected in 4 out of 40 cases (10.0%). Stromal macrophages were immunopositive in 28 out of 40 cases (70.0%). Lymphocytes showed PD-L1 expression in 3 out of 40 cases (7.5%). Simultaneous immunopositivity of stromal macrophages and tumor cells was detected in two MLH1/PMS2-deficient and two MSH2/MSH6-deficient cases.
Conclusion:
A subset of HNPCC-associated colorectal cancers in this study clearly showed PD-L1 expression of tumor epithelia and immune cells, therefore, the detection of PD-L1 status is useful.