In preclinical models of melanoma, loss of PTEN was associated with decreased intra-tumour T cells.4 In this study, higher levels of PTEN expression were associated with lower CD8 counts in CCOC (gCHM test p value < 0.0001 for an ordinal/ordinal association; Fig. 2d and Supplementary Table 4). Here, CD8A is linked to neoplasm.