AIDS-associated lung cancer has an increasing incidence, unaccounted for by smoking, and occurs consistently at a younger age than matched controls. We investigated whether known and new cancer-associated polyomaviruses, including the newly identified Merkel cell virus, may play a role in its etiopathogenesis. Although viruses target conserved pathways in cellular evolution, we are unable to suggest that the viruses studied here induce novel mechanisms of oncogenic dysregulation in AIDS-associated lung cancer.