Low CD4 cell count and nadir, CD4 count-nadir differential, and CD4:CD8 ratio nadir were associated with increased 2-year risk of incident virus-associated cancers in models adjusted for demographics and smoking (hazard ratios 1.2–1.3 per 100 or 0.1 unit decrease, respectively; p < 0.01). This evidence concerns the gene CD8A and cancer.