Deep brush-based cytology in tonsils resected for benign diseases.

A fraction of oropharyngeal cancer (OPC), especially in the tonsil, is caused by human papillomavirus (HPV), mainly HPV16. Noninvasive diagnostic methods to detect precancerous lesions in the tonsil would be useful, e.g., liquid-based cytology (LBC). However, ill-characterized precancerous lesions may be hidden in the depth of the tonsillar crypts. We therefore conducted a study on HPV and tonsillar precancerous lesions to evaluate, among other things, the utility of LBC obtained by deep brushing of the resected tonsils. Two hundred non-paediatric patients (mean age: 30.3 years) who underwent tonsillectomy for infection-related conditions (69%) or other conditions (mainly obstructive sleep apnoea, 31%) were included. An ultra-sensitive Luminex bead-based platform was used to test for the DNA of 21 mucosal HPV types; 56% of slides were unsatisfactory due to low number of squamous epithelial cells or the masking effect of a large number of lymphocytes. Three patients (1.5%; 95% CI: 0.5-4.3) showed suspicious cytological findings (atypical squamous cells-cannot exclude high-grade squamous intraepithelial lesion, ASC-H) while 3 others were HPV-positive (2 for HPV16 and 1 for HPV39). None of the ASC-H patients and HPV-positive patients showed dysplasia at histological examination. The rarity of HPV infection in the tonsil conflicts with the relatively frequent detection of the virus in the mouth. In conclusion, aggressive deep brushing of tonsils, while hardly applicable in vivo, is unlikely to be a reliable method to detect precancerous lesions. The absence of OPC screening modalities places the priority on multi-purpose primary prevention strategies, i.e., HPV vaccination and reduction of smoking and drinking.

Inactivation of the putative suppressor gene DOK1 by promoter hypermethylation in primary human cancers.

The DOK1 gene is a putative tumour suppressor gene located on the human chromosome 2p13 which is frequently rearranged in leukaemia and other human tumours. We previously reported that the DOK1 gene can be mutated and its expression down-regulated in human malignancies. However, the mechanism underlying DOK1 silencing remains largely unknown. We show here that unscheduled silencing of DOK1 expression through aberrant hypermethylation is a frequent event in a variety of human malignancies. DOK1 was found to be silenced in nine head and neck cancer (HNC) cell lines studied and DOK1 CpG hypermethylation correlated with loss of gene expression in these cells. DOK1 expression could be restored via demethylating treatment using 5-aza-2'deoxycytidine. In addition, transduction of cancer cell lines with DOK1 impaired their proliferation, consistent with the critical role of epigenetic silencing of DOK1 in the development and maintenance of malignant cells. We further observed that DOK1 hypermethylation occurs frequently in a variety of primary human neoplasm including solid tumours (93% in HNC, 81% in lung cancer) and haematopoietic malignancy (64% in Burkitt's lymphoma). Control blood samples and exfoliated mouth epithelial cells from healthy individuals showed a low level of DOK1 methylation, suggesting that DOK1 hypermethylation is a tumour specific event. Finally, an inverse correlation was observed between the level of DOK1 gene methylation and its expression in tumour and adjacent non tumour tissues. Thus, hypermethylation of DOK1 is a potentially critical event in human carcinogenesis, and may be a potential cancer biomarker and an attractive target for epigenetic-based therapy.

The role of the T-N tract in advanced stage tongue cancer.

BACKGROUND: We investigated the role of the soft tissue tract between the primary tumor and the neck lymph nodes, the "T-N tract," in patients with tongue squamous cell carcinoma at an advanced stage. METHODS: We performed a compartmental tongue surgery in 233 patients. Cumulative incidence of relapses and overall survival curves were compared by T-N tract involvement. Multivariate Cox proportional hazards models were used to assess the independent role of T-N tract. RESULTS: At 4 years of follow-up, patients with disease in the T-N tract experienced a significantly more distant recurrence (40%) than did patients without T-N tract involvement (22%; P = .02). Multivariate Cox models indicate a significant almost triple risk of distant metastases (hazard ratio [HR], 2.70; 95% CI, 1.01-7.19; P = .05) and double risk of death (HR, 2.09; 95%CI, 1.13-3.85; P = .02) in patients with "T-N tract involvement." CONCLUSIONS: Our data show that the T-N tract plays an important role in prognosis and survival in patients with tongue cancer.

Prevalence and Transmission of Beta and Gamma Human Papillomavirus in Heterosexual Couples.

BACKGROUND: Beta (ß) and gamma (γ) human papillomavirus (HPV) are commonly found on the skin. Few of the ß types are associated with nonmelanoma skin cancer. Little is known about transmission patterns of these HPV, specifically in the anogenital (AG) areas. The primary objective of this study was to examine the AG concordance and transmission of ß and γHPV types between heterosexual couples. METHODS: Archival samples from a previously published study examining concordance of alpha HPV types between couples were tested for ß and γHPV. Hand, mouth, and genital samples were obtained 5 times over a 6-week period. RESULTS: Of the 21 couples examined, ß and γHPV were detected in AG sites in 67% and 30% of men, respectively, and 41% and 25% of women. Positive concordance for ß and γHPV was 27% and 20%, respectively, which was greater than the observed concordance between noncouples (10% for ßHPV and 4% for γHPV). Transmission rate of ßHPV between AG areas was 15.9 (95% confidence interval [CI], 3.3-46.5) per 100 person months for men-to-women at risk and for γHPV was 6.6 (95% CI, .2-36.7). Risks for women-to-men were similar. CONCLUSIONS: Beta and γHPV are common in the AG area, and data suggest that they can be sexually transmitted.

Prevalence of human papillomavirus in tonsil brushings and gargles in cancer-free patients: The SPLIT study.

OBJECTIVE: To evaluate human papillomavirus (HPV) prevalence in the tonsil using extensive ex vivo brushing and gargling in a large age-stratified sample of cancer-free patients. MATERIALS AND METHODS: From 2012 to 2016, consecutive patients undergoing tonsillectomy for benign indications in 19 French University Hospitals were invited to participate in the SPLIT study. Immediately after resection, half-tonsils were extensively brushed at the pathology laboratories on the surface epithelium and in tonsil crypts to collect exfoliated cells. In 11 centers, patients aged 15 and over (adults) were also asked to provide gargle samples before surgery. HPV-DNA detection used a very sensitive Luminex technology to evaluate 21 HPV types. RESULTS: Tonsil brushings from 692 patients aged 1-70 years and gargles from 268 adults were tested for HPV. Among adults, overall HPV prevalence was 3.6% in tonsil brushings and 13.1% in gargles and HPV16 prevalence was 2.2% and 4.1%, respectively. Among 139 children, tonsil brushings were positive in two girls (1.4%). Percent agreement in HPV detection in paired tonsil brushings and gargles in adults was 85.8% and positive agreement 9.5%. HPV prevalence in gargles significantly varied by sex (prevalence ratio in men vs women=2.1; 95% confidence interval; 1.1-4.1) and tonsillectomy indication (non-infectious vs. infectious=4.9; 1.4-17.0). CONCLUSION: HPV infection is infrequent in tonsil brushings of cancer-free children and adults. In contrast, HPV infection in gargles in adults is rather common. Low agreement in paired tonsil brushings and gargles suggests that gargle is not representative of HPV prevalence in the tonsil.