CD4 and neoplasm: Tissue segmentation and cell phenotyping based on total DAPI+ cells was performed on regions of interest encompassing the entire SCC deposit and the surrounding adjacent stroma to quantify the number of total CD3+ T cells, CD4+ helper T cells, CD8+ killer T cells, CD3+PD-1+ T cells, CD3+CD8+granzyme B+ activated killer T cells, CD68+MHC class II+ PD-L1+/- antigen-presenting cells, CD3+CD8+CD103+ tissue-resident memory T cells, CD3+CD8+CD103+granzyme B+ activated tissue-resident memory T cells and panCK+PD-L1+/- tumour cells.