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Objectives: Due to their location in the entrance of the aero‐digestive tract, tonsils are steadily exposed to viruses. Human papilloma virus (HPV) and Epstein‐Barr virus (EBV) are two potentially oncogenic viruses that tonsils encounter. The incidence of HPV positive tonsillar cancer is on the rise and it is unknown when infection with HPV occurs.

Aim: To investigate if tonsils are infected with HPV and EBV, to study the co‐expression of HPV and its surrogate marker p16, and to evaluate the number of EBV positive cells in benign tonsillar disease.

Materials and Methods: Tonsils from 40 patients in a university hospital were removed due to hypertrophy, chronic or recurrent infection. These were analyzed for presence of HPV, its surrogate marker p16, and EBV. HPV was studied using PapilloCheck (a PCR method), while p16 was identified in epithelial and lymphoid tissue with immunohistochemistry and EBV using EBER‐ISH (Epstein‐Barr encoding region–in situ hybridization).

Results: HPV was not detected, and p16 was present at low numbers in all epithelial samples as well as in 92.5% of the lymphoid tonsillar samples. At least one EBER‐positive cell was seen in 65% of cases. Larger numbers of EBER‐expressing cells were only seen in two cases.

Conclusion: These findings demonstrate that EBV and HPV infect tonsils independently, but further studies are warranted to confirm their infectious relationship.

Level of Evidence: Cross‐sectional study

Background: Sinonasal inverted papilloma (SIP) is a benign tumour originating from the sinonasal mucosa showing an extensive growth pattern, a high risk of recurrence and a 5–10% risk to malignify. Epstein-Barr virus (EBV) is an oncogenic herpesvirus which infects most individuals via the saliva eliciting a latent infection. Previous studies have been reporting variable data on EBV in SIP, and there is no present appreciation regarding the association between these.

Aims/objectives: The aims were to investigate the presence and count of EBV in SIP and map the viral distribution in the epithelium versus the connective tissue.

Material and method: Fifty-three SIP patients were identified in the Pathology Department register at the University Hospital of Umeå. The biopsies were analysed with Epstein-Barr Encoded Region (EBER) in situ hybridization. EBER-positive cells were counted in the epithelium and connective tissue.

Results: We found EBER-stained cells in 30% of the cases, where 19% of these had an abundance of stained cells, and the rest showed a low count.

Conclusions/significance: These findings demonstrate a low EBV count in SIP. EBV is less likely to be a causative agent in the formation of SIP, or its malignant transformation.

Purpose: Apart from tobacco and alcohol, viral infections are proposed as risk factors for laryngeal cancer. The occurrence of oncogenic viruses including human papilloma virus (HPV) and Epstein–Barr virus (EBV), in laryngeal squamous cell carcinoma (LSCC) varies in the world. Carcinogenesis is a multi-step process, and the role of viruses in LSCC progression has not been clarified. We aimed to analyze the presence and co-expression of HPV, EBV, human cytomegalovirus (HCMV) and human adenovirus (HAdV) in LSCC. We also investigated if p16 can act as surrogate marker for HPV in LSCC.

Methods: Combined PCR/microarrays (PapilloCheck®) were used for detection and genotyping of HPV DNA, real-time PCR for EBV, HCMV and HAdV DNA detection, and EBER in situ hybridization (EBER-ISH) for EBV detection in tissue from 78 LSCC patients. Additionally, we analyzed p16 expression with immunohistochemistry.

Results: Thirty-three percent (26/78) of LSCC tumor samples were EBV positive, 9% (7/78) HCMV positive and 4% (3/78) HAdV positive. Due to DNA fragmentation, 45 samples could not be analyzed with PapilloCheck®; 9% of the remaining (3/33) were high-risk HPV16 positive and also over-expressed p16. A total of 14% (11/78) of the samples over-expressed p16.

Conclusion: These findings present a mapping of HPV, EBV, HCMV and HAdV, including the HPV surrogate marker p16, in LSCC in this cohort. Except for EBV, which was detected in a third of the samples, data show viral infection to be uncommon, and that p16 does not appear to be a specific surrogate marker for high-risk HPV infection in LSCC.