Developing and Validating a Multivariable Prognostic-Predictive Classifier for Treatment Escalation of Oropharyngeal Squamous Cell Carcinoma: The PREDICTR-OPC Study.

PURPOSE: While there are several prognostic classifiers, to date, there are no validated predictive models that inform treatment selection for oropharyngeal squamous cell carcinoma (OPSCC).Our aim was to develop clinical and/or biomarker predictive models for patient outcome and treatment escalation for OPSCC. EXPERIMENTAL DESIGN: We retrospectively collated clinical data and samples from a consecutive cohort of OPSCC cases treated with curative intent at ten secondary care centers in United Kingdom and Poland between 1999 and 2012. We constructed tissue microarrays, which were stained and scored for 10 biomarkers. We then undertook multivariable regression of eight clinical parameters and 10 biomarkers on a development cohort of 600 patients. Models were validated on an independent, retrospectively collected, 385-patient cohort. RESULTS: A total of 985 subjects (median follow-up 5.03 years, range: 4.73-5.21 years) were included. The final biomarker classifier, comprising p16 and survivin immunohistochemistry, high-risk human papillomavirus (HPV) DNA in situ hybridization, and tumor-infiltrating lymphocytes, predicted benefit from combined surgery + adjuvant chemo/radiotherapy over primary chemoradiotherapy in the high-risk group [3-year overall survival (OS) 63.1% vs. 41.1%, respectively, HR = 0.32; 95% confidence interval (CI), 0.16-0.65; P = 0.002], but not in the low-risk group (HR = 0.4; 95% CI, 0.14-1.24; P = 0.114). On further adjustment by propensity scores, the adjusted HR in the high-risk group was 0.34, 95% CI = 0.17-0.67, P = 0.002, and in the low-risk group HR was 0.5, 95% CI = 0.1-2.38, P = 0.384. The concordance index was 0.73. CONCLUSIONS: We have developed a prognostic classifier, which also appears to demonstrate moderate predictive ability. External validation in a prospective setting is now underway to confirm this and prepare for clinical adoption.

Variation in access to specialist services for neurosurgical procedures in adults with epilepsy in England, a cohort study.

PURPOSE: To understand if primary consultation at tertiary epilepsy centres (TEC) in England impacts access to neurosurgical procedures (resective surgery, vagus nerve stimulator [VNS], deep brain stimulator [DBS]). METHODS: Adults with epilepsy, and with a first neurology outpatient visit (index) between 01/01/2013 and 31/12/2015, were followed using English Hospital Episode Statistics from index date to 31/12/2019. Analyses were stratified by geographic location, learning disability record, and whether the index or follow-up visits were at a TEC. RESULTS: 84,093 people were included, with mean 5.5 years of follow-up. 12.4% of the cohort had learning disability (range 10.1%-17.4% across regions). TEC consultations varied by National Health Service regions and Clinical Commissioning Groups. 37.5% of people (11.2%-75.0% across regions) had their index visit at a TEC; and, of those not initially seen at a TEC, 10.6% (6.5%-17.7%) subsequently attended a tertiary centre. During follow-up, 11.1% people (9.5%-13.2%) visited a neurosurgery department, and 2.3% of those (0.9%-5.0%) then underwent a neurosurgical procedure, mainly VNS implantation. Median time from index date to first visit at a neurosurgery centre was 7 months (range 6-8 months across regions) and 40 months to procedure (36.5-49 months, 37.0 months in people with index visit at a TEC and 49.0 months otherwise). People with learning disability were less likely to have resective surgery (<0.5% versus 1.0% in those without) and more likely to undergo VNS implantation (5.8% versus 0.8%). CONCLUSION: Although clinically recommended for suitable individuals, neurosurgical procedures in epilepsy remain uncommon even after consultation at a TEC. Geographical variation in access to TECs was present.

Treating the N0 neck in early stage oral cancer: a pause for re-assessment?

The incidence of metastases following neck dissection in the apparent lymph node negative neck in oral cancer is between 7% and 33%; early resection of cervical metastases may well increase survival. Modern imaging techniques can reduce the yield of previously undiagnosed metastatic nodes in elective neck dissection (END). An audit of 112 consecutive cases was conducted to determine the proportion of undiagnosed nodal metastases, after END. There were neck metastases in 10 cases (9%), which were mainly (but not all) micrometastic. The 20% likelihood of nodal metastases was only apparent in primary tumours greater than 6 mm thick. The length of inpatient stay was increased from 3.7 to 16.5 days with free vascularised transfer. There were complications including cranial nerve damage. There were two peri-operative deaths. No ipsilateral neck failures occurred, median follow up was 937 days. To reduce unnecessary END, resection can be undertaken as a prior procedure, subsequently only carrying out END on tumours greater than 6 mm, or with unfavourable tumour characteristics.

Serial step sections at narrow intervals with immunohistochemistry are required for accurate histological assessment of sentinel lymph node biopsy in oral squamous cell carcinoma.

BACKGROUND: Sentinel lymph node (SLN) biopsy is an accurate staging modality in early oral squamous cell carcinoma (OSCC), but its accuracy relies on labor-intensive histopathology protocols. We sought to determine whether serial step sections with immunohistochemistry (SSSIHC) at narrow intervals of the entire SLN are required to accurately exclude metastasis. METHODS: Consecutive SLN biopsies over a 13-year period were retrospectively evaluated. If the index section was negative for carcinoma, the entire SLN was subjected to SSSIHC at 150 µm intervals. The first section level and total number of section levels to contain carcinoma were recorded. RESULTS: One hundred and eighteen SLN+ from 90 patients were included. SSSIHC upstaged the nodal status in 19.5% of patients. Metastasis was identified in 16.7% and 10.2% beyond section levels 4 and 6, respectively. Among SLNs requiring SSSIHC, 47.5% contained carcinoma in a single section level. CONCLUSION: SSSIHC of the entire SLN at 150 µm intervals are required to identify occult metastasis in OSCC.

TNM 8 staging is a better prognosticator than TNM 7 for patients with locally advanced oral cavity squamous cell carcinoma treated with surgery and post-operative radiotherapy.

PURPOSE: To assess TNM 8 staging in discriminating overall survival (OS) amongst patients with locally advanced oral cavity squamous cell carcinoma (OCSCC) treated with surgery and post-operative radiotherapy (PORT), compared to TNM 7. MATERIAL AND METHODS: Data from OCSCC patients treated with surgery and PORT between January 2010 and December 2018 were reviewed. Demographics, tumour characteristics and treatment response data were collected, and patients staged according to both TNM 7 and TNM 8. OS and disease free survival (DFS) were estimated using the Kaplan Meier method. Univariate and multivariable analyses were conducted for factors affecting OS, DFS and early disease recurrence within 12 months. RESULTS: Overall 172 patients were analyzed. Median follow up was 32 months for all patients and 48 months for surviving patients. TNM 8 staging demonstrated significant stratification of OS and DFS amongst the entire cohort, whereas TNM 7 staging did not. On multivariable analysis, TNM 8 stage, performance status (PS) and a positive surgical margin were prognostic for OS. Looking at disease recurrence within 12 months, TNM 8 stage IVB, presence of lymphovascular invasion (LVSI), younger age and lesser smoking history were predictive factors on multivariable analysis. CONCLUSION: TNM 8 is a good development of its predecessor in terms of predicting survival for patients with locally advanced OCSCC. We have also identified younger age (<60 years) and a smoking history of <10 pack years as risk factors for early disease recurrence, potentially representing a separate biological cohort within OCSCC patients.

Outcomes of salvage surgery for the oropharynx and larynx: a contemporary experience in a UK Cancer Centre.

INTRODUCTION: The purpose of this study was to review our recent experience of salvage surgery, comparing larynx and oropharynx recurrence patterns. METHODS: A single centre, retrospective review of salvage surgery for recurrent head and neck cancer including patients between 2008 and 2016. RESULTS: 61 patients were identified, 36 underwent salvage laryngectomy and 25 received oropharyngeal resections. The median overall survival of oropharyngeal recurrent tumors was 26 months (95% CI 15-118 months) and for laryngeal tumors was 23 months (95% CI 11-38 months), p = 0.1008. There was a significant overall survival benefit in patients with negative resection margin. The median survival in the negative margin group was 38 months (95% CI 25-108 months) compared to the positive margin group, 9 months (95% CI 5-15 months), p < 0.0001. CONCLUSION: Survival results following surgical salvage in the larynx and oropharynx appear to be similarly poor. Those patients with clear margins appear to have a significantly better prognosis.

Long-Term Mortality and Bone Safety in Patients with End-Stage Renal Disease Receiving Lanthanum Carbonate.

BACKGROUND/AIMS: This post-marketing observational study assessed the long-term safety of lanthanum carbonate (LaC) in US patients with end-stage renal disease (NCT00567723). METHODS: Patients (≥18 years old) undergoing dialysis, who had Medicare as their primary healthcare payer, and records in the United States Renal Data System were followed-up for 5 years. Patients who had received LaC for at least 12 consecutive weeks formed the exposed cohort. During the same time period, patients who had undergone dialysis for at least 12 consecutive weeks and had been treated with any other phosphate binder formed the primary comparator cohort. A historical cohort was also evaluated. Primary outcomes were all-cause mortality, and time to and incidence of first bone-fracture event requiring hospitalization. Secondary outcomes were time to first occurrence of and incidence of specific gastrointestinal (GI) disease, liver disease, malignancy, and major infectious episode requiring hospitalization. -Results: 2,026 and 8,094 patients were included in the exposed and primary comparator cohorts, respectively. A Cox proportional hazards model showed that patients receiving LaC were not at increased risk of all-cause mortality (adjusted hazard ratio 0.94; 95% CI 0.88-1.01; p = 0.078), bone fractures (0.86; 0.71-1.05; p = 0.130), specific GI disease (0.86; 0.76-0.97; p = 0.015), liver disease (0.88; 0.70-1.09; p = 0.236), malignancy (0.85; 0.54-1.34; p = 0.496), or major infectious episodes (0.87; 0.80-0.94; p < 0.001) requiring hospitalization compared with primary comparator patients. CONCLUSIONS: LaC was not associated with increased risk of mortality, bone fractures, or any secondary outcome.

High Dose Atorvastatin Associated with Increased Risk of Significant Hepatotoxicity in Comparison to Simvastatin in UK GPRD Cohort.

BACKGROUND & AIMS: Occasional risk of serious liver dysfunction and autoimmune hepatitis during atorvastatin therapy has been reported. We compared the risk of hepatotoxicity in atorvastatin relative to simvastatin treatment. METHODS: The UK GPRD identified patients with a first prescription for simvastatin [164,407] or atorvastatin [76,411] between 1997 and 2006, but with no prior record of liver disease, alcohol-related diagnosis, or liver dysfunction. Incident liver dysfunction in the following six months was identified by biochemical value and compared between statin groups by Cox regression model adjusting for age, sex, year treatment started, dose, alcohol consumption, smoking, body mass index and comorbid conditions. RESULTS: Moderate to severe hepatotoxicity [bilirubin >60µmol/L, AST or ALT >200U/L or alkaline phosphatase >1200U/L] developed in 71 patients on atorvastatin versus 101 on simvastatin. Adjusted hazard ratio [AHR] for all atorvastatin relative to simvastatin was 1.9 [95% confidence interval 1.4-2.6]. High dose was classified as 40-80mg daily and low dose 10-20mg daily. Hepatotoxicity occurred in 0.44% of 4075 patients on high dose atorvastatin [HDA], 0.07% of 72,336 on low dose atorvastatin [LDA], 0.09% of 44,675 on high dose simvastatin [HDS] and 0.05% of 119,732 on low dose simvastatin [LDS]. AHRs compared to LDS were 7.3 [4.2-12.7] for HDA, 1.4 [0.9-2.0] for LDA and 1.5 [1.0-2.2] for HDS. CONCLUSIONS: The risk of hepatotoxicity was increased in the first six months of atorvastatin compared to simvastatin treatment, with the greatest difference between high dose atorvastatin and low dose simvastatin. The numbers of events in the analyses were small.

HPV Involvement in Head and Neck Cancers: Comprehensive Assessment of Biomarkers in 3680 Patients.

BACKGROUND: We conducted a large international study to estimate fractions of head and neck cancers (HNCs) attributable to human papillomavirus (HPV-AFs) using six HPV-related biomarkers of viral detection, transcription, and cellular transformation. METHODS: Formalin-fixed, paraffin-embedded cancer tissues of the oral cavity (OC), pharynx, and larynx were collected from pathology archives in 29 countries. All samples were subject to histopathological evaluation, DNA quality control, and HPV-DNA detection. Samples containing HPV-DNA were further subject to HPV E6*I mRNA detection and to p16(INK4a), pRb, p53, and Cyclin D1 immunohistochemistry. Final estimates of HPV-AFs were based on HPV-DNA, HPV E6*I mRNA, and/or p16(INK4a) results. RESULTS: A total of 3680 samples yielded valid results: 1374 pharyngeal, 1264 OC, and 1042 laryngeal cancers. HPV-AF estimates based on positivity for HPV-DNA, and for either HPV E6*I mRNA or p16(INK4a), were 22.4%, 4.4%, and 3.5% for cancers of the oropharynx, OC, and larynx, respectively, and 18.5%, 3.0%, and 1.5% when requiring simultaneous positivity for all three markers. HPV16 was largely the most common type. Estimates of HPV-AF in the oropharynx were highest in South America, Central and Eastern Europe, and Northern Europe, and lowest in Southern Europe. Women showed higher HPV-AFs than men for cancers of the oropharynx in Europe and for the larynx in Central-South America. CONCLUSIONS: HPV contribution to HNCs is substantial but highly heterogeneous by cancer site, region, and sex. This study, the largest exploring HPV attribution in HNCs, confirms the important role of HPVs in oropharyngeal cancer and drastically downplays the previously reported involvement of HPVs in the other HNCs.

Milk supply related to childhood leukaemia treatment.

This literature review and case study answers the question: 'Do the late effects of childhood cranial radiation therapy include impacts on breastfeeding?' PubMed was searched for papers using the terms lactation and cranial radiotherapy or childhood cranial radiotherapy. The case study was written from one author's experience of helping a mother with a history of childhood cranial radiation therapy. The few available studies report a high rate of lactation failure in women who were treated with cranial radiation therapy for childhood cancer, but the exceptions indicate that lactation failure is not inevitable in this group of mothers. Breastfeeding may ameliorate some of the adverse effects of cranial radiation therapy. Health professionals caring for mothers with a history of cranial radiation therapy must balance encouraging women to breastfeed with preparing them for the possibility that they may be unable to do so.

Human papillomavirus infection is rare in nonmalignant tonsil tissue in the UK: implications for tonsil cancer precursor lesions.

The incidence of human papillomavirus (HPV)-associated tonsil cancer is increasing but the prevalence of HPV, and of premalignant precursors, in tonsil tissue is unknown. We aimed to assess prevalence of HPV infection in nonmalignant tonsillar crypt epithelia and to histopathologically characterise positive samples. Formalin-fixed paraffin-embedded (FFPE) tonsil tissue specimens were obtained from an age- and sex-stratified random sample of patients aged 0-69 years whose paired tonsils were archived following elective tonsillectomy at hospitals throughout England and Southern Scotland from 2004 to 2008. Homogenised fresh-frozen tonsil tissue was also obtained from archive for two random subsets of males aged 25-34 and over 44. HPV status was assessed in all samples for 20 mucosal HPV types by GP5+/6+ polymerase chain reaction (PCR) enzyme immunoassay and by HPV16 type-specific PCR targeting the E6 gene. In the homogenised material, HPV status was also assessed for 44 HPV types by SPF10-PCR enzyme immunoassay. Of 4,095 randomly sampled FFPE specimens, amplifiable DNA was extracted from 3,377 (82.5%) and from 511 of 524 (97.5%) homogenised tonsils. HPV DNA was identified in 0 of 3,377 (0%, 95% CI 0-0.089%) fixed samples and 0 of 511 (0%, 95% CI 0-0.58%) homogenised samples. This suggests HPV infection may be rare in tonsil reticulated crypt epithelia. Furthermore, we found no evidence of HPV-associated premalignant neoplasia. These data suggest that if HPV-associated premalignant lesions do occur, they are likely to be rare and may have a high risk of progression to carcinoma.

Prospective technical validation and assessment of intra-tumour heterogeneity of a low density array hypoxia gene profile in head and neck squamous cell carcinoma.

BACKGROUND AND PURPOSE: Tumour hypoxia is associated with a poor prognosis in head and neck squamous cell carcinoma (HNSCC), however there is no accepted method for assessing hypoxia clinically. We aimed to conduct a technical validation of a hypoxia gene expression signature using the TaqMan Low Density Array (TLDA) platform to investigate if this approach reliably identified hypoxic tumours. MATERIALS AND METHODS: Tumour samples (n=201) from 80 HNSCC patients were collected prospectively from two centres. Fifty-three patients received pimonidazole prior to surgery. TaqMan Low Density Array-Hypoxia Scores (TLDA-HS) were obtained by quantitative real-time PCR (qPCR) using a 25-gene signature and customised TLDA cards. Assay performance was assessed as coefficient of variation (CoV). RESULTS: The assay was sensitive with linear reaction efficiencies across a 4 log(10) range of inputted cDNA (0.001-10 ng/µl). Intra- (CoV=6.9%) and inter- (CoV=2.0%) assay reproducibility were excellent. Intra-tumour heterogeneity was lower for TLDA-HS (23.2%) than for pimonidazole (67.2%) or single gene measurements of CA9 (62.2%), VEGFA (45.0%) or HIG2 (39.4%). TLDA-HS in HNSCC cell lines increased with decreasing pO(2). TLDA-HS correlated with Affymetrix U133 Plus 2.0 microarray HS (p<0.01) and positive pimonidazole scores (p=0.005). CONCLUSIONS: Gene expression measurements of hypoxia using a 25-gene signature and TLDA cards are sensitive, reproducible and associated with lower intra-tumour heterogeneity than assaying individual genes or pimonidazole binding. The approach is suitable for further assessment of prognostic and predictive capability in clinical trial material.

Clinico-pathologic conference: case 4. Langerhans cell histiocytosis (LCH).

A 13-month-old Japanese boy presented with painless swelling in a left mandible and cheek. Intraoral examination revealed swelling in the left mandible and hemorrhage of oral mucosa due to biting. CT images revealed a wide osteolytic lesion of the left mandible with floating teeth. Biopsy was carried out and histopathological diagnosis was discussed.

Extracapsular spread in oral squamous cell carcinoma.

BACKGROUND: Extracapsular spread (ECS) in the cervical lymph nodes represents the most significant adverse prognostic indicator in oral squamous cell carcinoma (OSCC). METHODS: In a consecutive cohort of OSCC treated by primary surgery, ECS was seen in 25% (101) of 400 patients. RESULTS: ECS doubled the incidence of local recurrence and distant metastases, but tripled regional failure. The recurrences occurred sooner in ECS than in non-ECS cases (206 vs 334 days, p = .04). Patients with macroscopic ECS had a 5-year overall survival (OS) of 19% compared with 31% in microscopic ECS. MRI neck staging offered poor sensitivity, especially in microscopic ECS. Age >75 years, smoking, and heavy use of alcohol were independent predictors of ECS, which may implicate a failure of immunosurveillance by the host as much as adverse biology of the tumor. CONCLUSIONS: Reporting of ECS is essential in accurate prognostication, and we advocate that all patients with OSCC and ECS should be grouped as pN3 on the basis of their prognosis. (c) 2009 Wiley Periodicals, Inc. Head Neck, 2010.

Determinants of outcome following surgery for oral squamous cell carcinoma.

The recent changes in incidence and prevalence of oral squamous cell carcinoma in relation to gender and age mirror the changing patterns of exposure to tobacco and alcohol, the main etiological agents. Most cases of oral cancer are managed by surgery, often combined with radiotherapy. Histopathological assessment of the resection specimen provides information vital for postoperative management and prognosis. This review considers the full range of histological determinants of outcome in relation to the primary oral tumor and any metastatic involvement of the cervical lymphatic system, together with an outline of more general patient factors that may also impact on morbidity and mortality rates.

Validation of death and suicide recording on the THIN UK primary care database.

PURPOSE: Data from a cohort study were used to investigate death and cause of death (COD) recording on the THIN UK primary care database. METHODS: Subjects from 118 practices had a body mass index recorded, 2002-2003 (index date), no recent pregnancy or emotional event, or cancer. Coded and free text entries were searched for a COD for deaths dated < or = 485 days after index date. External documents were requested when date or COD were unclear, suicide was possible, and for a random sample of 40 patients with a COD identified. RESULTS: Five of 1399 deaths dated within 1 year of the index date had not died (positive predictive value 99.6%) and 4 of 222 dated within 366-485 days had died during the year (sensitivity 99.7%). A database COD was identified for 887 (63.4%) with external documents received for 597 (92.8% requested). Of 40 compared with external sources, the underlying COD was on the database in 33 (82.5%), and could be identified as such in 26 (65%). The date was within 1 day of that on external documents in 504 (94.9%) with a date of death but 3 (5.7%) with only a transfer-out of practice date. One of seven suicides was recorded as such. CONCLUSION: Any database record of death or its date is reliable, but transfer-out date is often later. Studies of COD or acute, potentially fatal conditions will miss cases unless a COD is obtained for all fatalities. Most suicides are not noted as such on the electronic record.

p16 Promoter methylation is a potential predictor of malignant transformation in oral epithelial dysplasia.

Management of the patient with oral epithelial dysplasia depends on the ability to predict malignant transformation. Histologic grading of this condition fails in this regard and is also subject to interpathologist and intrapathologist variability. This study uses longitudinal clinical samples to explore the prognostic value of a previously validated panel of methylation biomarkers in a cohort of patients with histologically proven oral dysplasia. Methylation enrichment pyrosequencing assays were used to provide the sensitivity of traditional methylation-specific PCR with the additional specificity advantages of a subsequent confirmatory sequencing reaction. In 57% (8 of 14) patients with a lesion that transformed to oral squamous cell carcinoma, 26% (26 of 100) of longitudinal samples collected over > or =3 years showed p16 methylation. Only 1% (2 of 184) of samples from 8% of patients (2 of 24) not undergoing malignant transformation within 3 years had p16 methylation. Both of these samples with p16 promoter methylation were the most recently collected and the patients remain under continuing clinical review. Promoter methylation of MGMT, CYGB, and CCNA1 did not correlate with malignant progression. We thus conclude that methylation of the p16 gene promoter shows promise as a predictor for malignant transformation (Fisher's exact, P = 0.002) in a subset of patients.

CD30-positive T-cell lymphoproliferative disorder of the oral mucosa--an indolent lesion: report of 4 cases.

Four cases of CD30-positive T-cell lymphoproliferative disorder (CD30+ LPD) of the oral mucosa are described. This article aims to draw attention to this entity and to emphasize its usual benign clinical behavior despite its resemblance to T-cell lymphoma. All the patients were adults. Three of the lesions were on the dorsal surface of the tongue and 1 affected the buccal mucosa. All biopsies showed a dense lymphoid infiltrate composed of CD30+ atypical T cells with a polymorphous infiltrate in the background, which included eosinophils. In 1 case, monoclonal T-cell expansion was detected by molecular techniques. Three cases tested for Epstein-Barr virus were all negative. It is concluded that primary CD30+ T-cell LPD of the oral mucosa can be regarded as the oral counterpart of cutaneous CD30+ LPD such as lymphomatoid papulosis or anaplastic large cell lymphoma. Recognition of the condition is important to avoid overtreatment.

The role of pyrosequencing in head and neck cancer epigenetics: correlation of quantitative methylation data with gene expression.

OBJECTIVE: To evaluate promoter methylation quantitation using recently described pyrosequencing techniques by correlation with messenger RNA (mRNA) expression. DESIGN: DNA was extracted from tissue samples and was subjected to bisulphite conversion. Quantitative methylation data for multiple CpG sites in each of 9 gene promoters were obtained for tumors using pyrosequencing. RNA was extracted and converted to complementary DNA, and this formed the template for relative quantitation assays of the expression of each gene by real-time reverse transcription-polymerase chain reaction. SETTING: Academic research. PATIENTS: Thirty-seven patients with head and neck squamous cell carcinoma. MAIN OUTCOME MEASURES: The genes studied were P16 (OMIM 600160), cyclin A1 (OMIM 604036), RARB (OMIM 180220), E-cadherin (OMIM 192090), MGMT (OMIM 156569), STAT1 (OMIM 600555), ATM (OMIM 607585), hMLH1 (OMIM 120436), and TIMP3 (OMIM 188826). Immunohistochemistry was also performed for p16. RESULTS: STAT1, TIMP3, ATM, and hMLH1 promoters were essentially unmethylated in all cases. The data for cyclin A1 (Spearman rank correlation, rho = -0.53; P < .001), MGMT (rho = -0.53, P < .001), and RARB (rho = -0.34, P =.02) showed the expected negative correlation between levels of methylation and mRNA expression. The data relating to E-cadherin were inconclusive. Surprisingly, P16 expression was statistically significantly greater in those cases with higher levels of methylation (rho = 0.57, P < .001), a finding at odds with assumptions usually made in the literature relating gene promoter methylation to reduced gene expression. The results from p16 immunohistochemistry were in keeping with the mRNA data, but the number of positive staining samples proved too few for statistical analysis. CONCLUSIONS: These data present a novel perspective on head and neck cancer epigenetics and reveal new and some unexpected associations and findings. The advantages of pyrosequencing over nonquantitative techniques are discussed in analyses of this nature.