Spatial analysis further demonstrated that CD4+ T-cell infiltration was significantly diminished in OTRs at both defined peritumoral zones: at IM1500 (500–1500 um from tumour edge), median CD4+ density was 1512 cells/mm2 (range 0–4475) in OTRs versus 2651 cells/mm2 (range 0–12,507) in immunocompetent patients, while at IM500, CD4+ densities were likewise lower in OTRs (1706 cells/mm2, range 448–7976) compared with immunocompetent individuals (4180 cells/mm2, range 0–11,992). Here, CD4 is linked to neoplasm.