Low prevalence of transfusion transmitted virus (TTV)-like DNA sequences in cystadenolymphoma and pleomorphic adenoma of the salivary glands.

Titers of transfusion transmitted virus (TTV)-like DNA in saliva samples have been reported 100-1,000 times higher than those of the corresponding sera, suggesting viral transmission by saliva droplets. The present study was conducted to determine whether TTV-like DNA sequence elements play a role in the pathogenesis of cystadenolymphoma or pleomorphic adenoma and if the parotid or the submandibular gland is a major source of TTV persistence. Sixty-two archival salivary gland samples (16 cystadenolymphomas, 13 pleomorphic adenomas, and 33 controls) and 23 corresponding saliva samples were examined using a polymerase chain reaction (PCR) for TTV DNA. All PCR products that displayed DNA bands were sequenced. Leder's stain and immunohistochemistry (anti-CD8, anti-CD20, anti-CD45R0, anti-CD68, and anti-Ki67/MiB1) were applied to detect possible changes associated with findings of TTV-like DNA sequences. Tissue displayed TTV-like DNA sequences in 8.1% (5/62; saliva: 47.8%, 11/23). Tissue that contained TTV-like DNA sequences was histologically indistinguishable from samples lacking such DNA. TTV appears to be only a bystander in cystadenolymphoma, pleomorphic adenoma, and other salivary gland affections. Neither of the glands seems to be a major source of TTV persistence.