Short-fragment PCR assay for highly sensitive broad-spectrum detection of human papillomaviruses in laryngeal squamous cell carcinoma and normal mucosa: clinico-pathological evaluation

The aim of the study was to determine the prevalence and genotypes of HPV infection in laryngeal cancer specimens, normal mucosa obtained from the surgical margin and laryngeal nodules using a novel high sensitive and specific SPF(10) HPV DNA test, PCR/DEIA method and INNO-LiPA genotyping assay. The correlation between HPV presence and clinico-pathological features was analyzed. Tissue samples were collected from 93 primary laryngeal squamous cell carcinoma (LSCC), 49 specimens of normal mucosa and from 22 specimens of laryngeal nodules serving as control group. HPV DNA was amplified by the short PCR fragment (SPF(10)) primer set using HPV DNA enzyme immunoassay (DNA/DEIA) method and INNO-LiPA HPV genotyping assay. Human papillomavirus was detected in 33 (35.5%) of the 93 samples from LSCC, in 4 (8.2%) of 49 samples of the normal mucosa and it was not detected in any of the sample from the control group. Twenty-eight of 33 (81.8%) were positive for HPV-16, 6 of 33 (18.2%) were positive for HPV-18 and 5 of 33 (15.1%) were positive for HPV-33. Multiple infection was found in 5 of 33 (15.1%); 3 samples were positive for HPV-16 and HPV-33, 2 samples for HPV-16 and HPV-18. There was a statistically significant correlation between the presence of HPV in LSCC tumors and in control group samples and between the presence of HPV in the tumors and normal mucosa from the free surgical margin. The presence of HPV infection in 35.5% of the cases suggests a possible role in the etiology of laryngeal cancer and supports the role of high-risk types of HPV (16, 18 and 33) in LSCC. HPV infection is not likely to influence survival rates as an independent prognostic factor in patients with laryngeal cancer.