Human papillomavirus prevalence in lung carcinomas in Bulgaria.

A possible association between high-risk human papillomaviruses (HPV) and lung cancer has been investigated for decades with discrepant results. The aim of this study was to determine the prevalence of HPV16 and 18 in Bulgarian patients with lung cancer. Two hundred and nine biopsy specimens from patients with histologically proven lung cancer and without cancer were analyzed. Each sample was subjected to three parallel PCRs using broad spectrum GP5+/6+ primers and type-specific (TS) primers for HPV types 16 and 18. Of the 132 lung carcinoma samples, 33 (25%) were positive for HPV16 and/or HPV18 by TS PCR whereas only five (3.8%) samples were HPV positive by consensus PCR. All non-malignant controls were HPV negative. HPV18 was the more prevalent, being found in 11.4% of samples, followed by HPV16 in 9.1% samples; 4.5% of lesions were positive for both HPV16 and HPV18. HPV16/18 were most prevalent in small cell carcinoma (29.2%) and least prevalent in squamous cell carcinoma (23.3%). HPV was only detected in squamous cell carcinoma and adenosquamous carcinoma by consensus PCR. This study revealed a high HPV16/18 prevalence in lung carcinoma samples from Bulgarian patients when TS PCR was used to detect them. The difference between HPV positivity as detected by consensus and by TS PCR was significant, indicating the importance of methodological issues in explaining the discrepancies between previous studies. HPV18 was more common than HPV16. No association between HPV16/18 status and histopathological diagnosis was identified.

Detection of Merkel Cell Polyomavirus in Respiratory Tract Specimens.

OBJECTIVE: The role of Merkel cell polyomavirus (MCPyV) as a respiratory pathogen is controversial. The aim of this study was to determine the prevalence of MCPyV in patients with acute respiratory diseases and chronic lung diseases, including lung cancer, in order to evaluate the association between MCPyV infection and respiratory diseases. METHODS: This study included 221 specimens (133 nasopharyngeal swabs and 88 lung biopsy specimens) obtained from patients with acute respiratory diseases and chronic lung diseases, including lung cancer. The detection of MCPyV was performed via nested polymerase chain reaction. RESULTS: MCPyV positivity was 4.3% on average. All nasopharyngeal specimens were obtained from patients with acute respiratory diseases, and 8.2% of them were MCPyV DNA positive. There were no statistically significant differences in MCPyV prevalence according to age or gender. All specimens from nonmalignant chronic lung diseases and lung cancer were MCPyV negative. CONCLUSIONS: MCPyV was observed in specimens from patients with acute respiratory diseases, indicating that there may be a relationship between the virus and these diseases. We were not able to detect MCPyV in samples from patients with chronic lung diseases, including lung cancer, suggesting no association with MCPyV infection and no involvement of this polyomavirus in lung cancerogenesis.