In terms of PDCD1, the expression was positively associated with TOP2A expression in 12 tumor types, including BRCA, HNSC, HNSC-HPV−, HNSC-HPV+, KIRC, LGG, LIHC, LUAD, LUSC, PRAD, THCA (Rho = 0.191) and THYM, but a negative relationship in UCEC (all p values < 0.05). Here, TOP2A is linked to neoplasm.