The composition of immune cells in primary tumors of GINGIVO-BUCCAL SQUAMOUS CELL CARCINOMA patients with lymph node metastases (N stage) / without metastases and size (T stage) is currently unknown. Therefore, we studied tumor infiltrating immune cells in archived samples to find a correlation with pathological T and N stages of the disease.
The analysis of the location, density and functional orientation of different immune cell populations was done on 94 retrospective cases. Characterization of immune cells by immunohistochemistry (IHC) was done using the following markers : CD3, CD4, CD8, CD68, Granzyme B, CD14, CD15, HLADR, Arginase1, Neutrophil Elastase, CD56 and CD20. Quantification of immune cells was done at the invasive margins of tumor (IM) and tumor centre (CT) for each of the above markers.
Markers that inversely correlated significantly with tumor size, both at the invasive front and tumor centre, are CD3 (CT p=0.001; IM p=0.005) and CD68 (CT p=0.010; IM p=0.006). Absence of lymph node metastasis correlated significantly with high numbers of CD3 and CD8 positive cells in tumor margins and centre. ( CD3 – CT p=0.010, IM p<0.001; CD8-CT p=<0.001, IM p=0.001). Therefore, we proposed that quantification of CD3 and CD8 positive cells in primary tumors may predict disease progression. A deeper understanding of host tumor interactions and tumor immune escape strategies in SCC-GB is required.