Although few studies have specifically targeted the evaluation of CD8+ TILs in rectal cancer, several groups, including ours have previously identified intraepithelial TIL positivity as a favourable prognostic indicator in colorectal cancers, especially those characterised by microsatellite stability, a feature shared by the majority of rectal cancers (Baker et al, 2007). The gene discussed is CD8A; the disease is colorectal cancer.