Increased viral load correlates with improved survival in HPV-16-associated tonsil carcinoma patients

Evolution of testing for the diagnosis of human papillomavirus (HPV) status in head and neck squamous cell carcinoma: Where from and where to?

Human papillomavirus (HPV) is causally associated with head and neck squamous cell carcinomas with the strongest association in the oropharynx. HPV-associated oropharyngeal carcinomas have a different pathogenesis with distinct clinical features and better prognosis than HPV-negative oropharyngeal carcinomas which impacts staging and prognosis. It is, therefore, of clinical significance to accurately determine the HPV status, particularly in oropharyngeal carcinomas. In this review, the different test methods that are used for characterizing HPV status in head and neck squamous cell carcinomas, both conventional methods (p16 immunohistochemistry, HPV DNA in-situ hybridization, HPV DNA PCR, HPV E6/E7 mRNA RT-PCR, HPV RNA in-situ hybridization) as well as emerging novel approaches (HPV circulating tumour DNA, HPV16 E6 antibodies, oral HPV DNA/mRNA PCR), are discussed. Currently, a combined testing approach is favoured, using a sequential strategy of screening with p16 immunohistochemistry and confirming with HPV DNA PCR. HPV RNA in-situ hybridization could potentially serve as a single test owing to its good sensitivity and specificity. The use of liquid biopsies is gaining momentum with HPV circulating tumour DNA as the frontrunner in demonstrating promising clinical utility for early detection in HPV-associated oropharyngeal carcinomas. HPV16 E6 antibodies and oral HPV DNA PCR has potential utility as adjunct tests to aid diagnosis. In this rapidly evolving HPV testing landscape, we as clinicians and laboratorians must evolve and advocate for access to cost-effective accurate HPV testing globally.

Longitudinal cell-free DNA characterization by low-coverage whole-genome sequencing in patients undergoing high-dose radiotherapy

BACKGROUND AND PURPOSE

Current radiotherapy guidelines rely heavily on imaging-based monitoring. Liquid biopsy monitoring promises to complement imaging by providing frequent systemic information about the tumor. In particular, cell-free DNA (cfDNA) sequencing offers a tumor-agnostic approach, which lends itself to monitoring heterogeneous cohorts of cancer patients.

METHODS

We collected plasma cfDNA from oligometastatic patients (OMD) and head-and-neck cancer patients (SCCHN) at six time points before, during, and after radiotherapy, and compared them to the plasma samples of healthy and polymetastatic volunteers. We performed low-pass (on average 7x) whole-genome sequencing on 93 plasma cfDNA samples and correlated copy number alterations and fragment length distributions to clinical and imaging findings.

RESULTS

We observed copy number alterations in 4/7 polymetastatic cancer patients, 1/7 OMD and 1/7 SCCHN patients, these patients' imaging showed progression following radiotherapy. Using unsupervised learning, we identified cancer-specific fragment length features that showed a strong correlation with copy number-based tumor fraction estimates. In 4/4 HPV-positive SCCHN patient samples, we detected viral DNA that enabled the monitoring of very low tumor fraction samples.

CONCLUSIONS

Our results indicate that an elevated tumor fraction is associated with tumor aggressiveness and systemic tumor spread. This information may be used to adapt treatment strategies. Further, we show that by detecting specific sequences such as viral DNA, the sensitivity of detecting cancer from cell-free DNA sequencing data can be greatly increased.

The molecular characteristics of recurrent/metastatic HPV-positive head and neck squamous cell carcinoma: A systematic review of the literature

OBJECTIVES

About 17% of patients with human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC), which is mainly comprised of oropharyngeal SCC (OPSCC), will experience disease recurrence, which is often considered incurable when manifested at a metastatic and/or recurrent stage. We conducted a critical qualitative systematic review. Our objectives were to provide an overview of the molecular landscape of recurrent/metastatic HPV-positive HNSCC as well as novel molecular biomarkers.

DESIGN

A literature review was conducted to identify studies reporting on the molecular characteristics of recurrent/metastatic HPV-positive HNSCC, novel molecular biomarkers and treatment options. The reviews of abstracts, full articles, and revision of the included studies, followed by data extraction and quality assessment were performed by three independent assessors. All primary literature, such as retrospective, prospective, and clinical trials as well as basic research studies were considered, and the final search was conducted at the end of February 2023. The level of evidence was rated using the guidelines published by the Oxford Centre for Evidence-based Medicine and quality was assessed using the Newcastle-Ottawa Scale criteria.

RESULTS AND CONCLUSIONS

The literature search resulted in the identification of 1991 articles. A total of 181 full articles were screened, and 66 articles were included in this analysis. Several studies reported that recurrent/metastatic HPV-positive HNSCC had higher rates of TP53 mutation and were genomically similar to HPV-negative HNSCC. The detection of circulating tumour tissue-modified HPV DNA (ctHPVDNA) as a specific biomarker has shown promising results for monitoring treatment response and recurrence in the subset of HPV-positive HNSCC. In addition, evidence for targeted therapy in recurrent/metastatic HPV-positive HNSCC has emerged, including agents that inhibit overexpressed EGFR. Studies of combination immunotherapy are also underway. Our review outlines the latest evidence on the distinct molecular profiles of recurrent/metastatic HPV-positive HNSCC as well as the clinical potential of ctHPVDNA testing in routine practice. More controlled and longitudinal studies are needed to identify additional molecular targets and to assess the performance and benefits of novel molecular biomarkers in clinical practice.

Oncological outcomes post transoral robotic surgery (TORS) for HPV-associated oropharyngeal squamous cell carcinoma, a single-centre retrospective Australian study

We present a cohort review of TORS resection for HPV-associated oropharyngeal squamous cell carcinoma (OPSCC) and its associated oncological outcomes spanning a 10-year period. A retrospective case series review was performed of patients undergoing primary surgical treatment for HPV-associated OPSCC through the St. Vincent's Head and Neck Cancer service from 2011 to 2022. The primary outcomes were to investigate complete resection of the primary tumour, rates of recurrence, and survival analysis. Secondary outcomes included complications, rates of adjuvant therapy, sites of recurrence and rates of percutaneous endoscopic gastrostomy (PEG). 184 patients underwent TORS-based therapy with neck dissection, and guideline-directed adjuvant therapy for HPV-associated OPSCC. Our median follow-up was 46 months. The positive margin rate on final histopathology analysis was 10.9%. Adjuvant therapy was indicated in 85 patients (46%). The local recurrence rate was 10.9% with the majority (80%) of patients recurring in the first 3 years since treatment. The disease-specific survival at 3 years was 98.6% and at 5 years was 94.4%. The 3-year and 5-year OS for the cohort was 96.7% and 92.5%, respectively. The presence of extranodal extension and positive margins were associated with increased risk of recurrence, whereas adjuvant therapy was found to be a protective factor for both overall recurrence and survival. Major complications occurred in 12 patients (6.5%), resulting in one death. This study has demonstrated that primary surgical therapy for HPV-associated OPSCC is a safe and effective treatment modality with low local recurrence and complication rates, and overall survival benefits.

Human papillomavirus (HPV) load is higher in HPVDNA/p16 positive than in HPVDNA positive/p16 negative oropharyngeal squamous cell carcinoma but does not differ significantly between various subsites or correlate to survival

OBJECTIVE

Patients with human papillomavirus DNA positive (HPVDNA+) and p16ink4a overexpressing (p16+) oropharyngeal squamous cell carcinoma (OPSCC), especially those with cancer in the tonsillar and base of tongue subsites as compared to other OPSCC subsites have a better outcome than those with only HPVDNA+ or only p16+ cancer. Likewise having a high viral load has been suggested to be a positive prognostic factor. We therefore hypothesized, that HPV viral load could vary depending on OPSCC subsite, as well as with regard to whether the cancer was HPVDNA+ and p16+, or only HPVDNA+, or only p16+ and that this affected outcome.

MATERIAL AND METHODS

To address these issues HPV viral load was determined by HPV digital droplet (dd) PCR in tumor biopsies with previously known HPVDNA/p16 status from 270 OPSCC patients diagnosed 2000-2016 in Stockholm, Sweden. More specifically, of these patients 235 had HPVDNA+/p16+, 10 had HPVDNA+/p16-, 13 had HPVDNA-/p16+ and 12 had HPVDNA-/p16- cancer.

RESULTS

We found that HPVDNA+/p16+ OPSCC had a significantly higher viral load than HPVDNA+/p16- OPSCC. Moreover, there was a tendency for a higher viral load in the tonsillar and base of tongue OPSCC subsites compared to the other subsites and for a low viral load to correlate to a better clinical outcome but none of these tendencies reached statistical significance.

CONCLUSION

To conclude, the mean viral load in HPVDNA+/p16+ OPSCC was higher than in HPVDNA+/p16- OPSCC, but there was no statistically significant difference in viral load depending on OPSCC subsite or on clinical outcome.

Pretreatment Circulating HPV16 DNA Viral Load Predicts Risk of Distant Metastasis in Patients with HPV16-Positive Oropharyngeal Cancer

BACKGROUND

There are definite reasons to implement molecular diagnostics based on the measurement of human papillomavirus (HPV) DNA in liquid biopsy into clinical practice. It is a quick, repeatable, and health-safe test for cancer biomarkers in the blood. In this study, we investigated whether the circulating tumor-related HPV16 (ctHPV16) viral load (VL) in patients with oropharyngeal squamous cell carcinoma (OPSCC) was important for determining the risk of locoregional recurrence-free survival (LRFS), metastasis-free survival (MFS), and overall survival (OS).

METHODS

This study included 91 patients with ctHPV16-positive OPSCC who had been treated with radical radiotherapy and chemotherapy. The VL was measured using quantitative PCR (qPCR) and a probe specific for HPV16. Based on 10 years of follow-up, the 2-, 3-, 5-, and 9-year LRFS, MFS, and OS were estimated.

RESULTS

The 5-year actuarial LRFS, MFS, and OS rates of patients with ctHPV16-positive/OPSCC were 88%, 90%, and 81%, respectively. The VL was significantly higher in patients who subsequently developed distant metastases (DM) than in those who did not (VL 4.09 vs. 3.25; p = 0.009). In a Cox proportional hazards regression model for MFS, a higher ctHPV16 VL appeared to be a significant independent prognostic factor for the occurrence of DM (HR 2.22, p = 0.015). The ROC curve revealed a cutoff value of 3.556 for VL (p = 0.00001).

CONCLUSIONS

A high VL before treatment indicates patients with a significant risk of DM, and should be used in OPSCC treatment stratification.

Dynamics of oral human papillomavirus infection in healthy population and head and neck cancer

The recent increase in high-risk human papillomavirus (HR-HPV)-associated oral and oropharyngeal cancers has gained considerable importance due to their distinct clinical and molecular characteristics. However, the natural history of oral HPV from acquisition to persistence and malignant transformation is still unclear. The global prevalence of oral HPV infection in healthy individuals ranges from 0.67% to 35%, while 31%-38.5% in head and neck cancer (HNC). The persistence rate of oral HR-HPV infection is 5.5% -12.8% globally. India has the highest HNC burden due to apparent differences in predisposing factors compared with the West. The prevalence of oral HPV in healthy individuals and its contribution to HNC is less evident in Indian studies. HR-HPV-associated HNC in this region accounts for 26%, with an active infection in 8%-15% of these tumors. There is a lack of concordance in the expression of p16 as a surrogate marker for HPV detection in HNC because of differences in behavioral risk factors. Due to a lack of evidence, treatment de-escalation cannot be implemented despite the improved outcome of HPV-associated oropharyngeal cancers. This review critically analyzes the existing literature on the dynamics of oral HPV infection and HPV-associated HNC, identifying potential avenues for future research. A better understanding of the oncogenic role of HR-HPV in HNC will help to formulate novel therapeutic approaches and is expected to have a significant public health impact as preventive strategies can be implemented.

Oropharyngeal Carcinoma with a Special Focus on HPV-Related Squamous Cell Carcinoma

Human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV-OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the Union for International Cancer Control/American Joint Committee on Cancer staging system separates HPV-OPSCC from its HPV-negative counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment deintensification as a means to improve quality of life while maintaining acceptable survival outcomes. Owing to the distinct biology of HPV-OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage, highlighting the need for diagnostic biomarkers to aid in earlier detection. In this review, we highlight important advances in the epidemiology, pathology, diagnosis, and clinical management of HPV-OPSCC and underscore the need for a progressive understanding of the molecular basis of this disease toward early detection and precision care.

HPV status and HPV16 viral load in anal cancer and its association with clinical outcome

BACKGROUND

The incidence of anal cancer is increasing globally. Evidence-based improvement in early detection and management of this morbid cancer is thus required. In other cancers associated with Human Papillomavirus (HPV), viral status and dynamics, including viral load (VL) has been shown to influence clinical outcome. Our aim was to determine the influence of HPV status and HPV16 VL on the clinical outcomes of anal cancer patients.

METHODS

A total of 185 anal cancer lesions were genotyped for HPV. Of the HPV16 positive component, VL was determined using a digital droplet PCR assay. The association of qualitative HPV status and VL (low (<12.3), medium (12.3-57) and high (>57 copies/cell)) on overall survival and hazard of death was assessed.

RESULTS

Of the 185 cases, 164 (88.6%) samples were HPV positive. HPV16 was detected in 154/185 samples (83.2%). HPV positive status was associated with improved overall survival in the univariate analysis [hazard ratio (HR) of 0.44, 0.23-0.82, p = 0.01]. When adjusted by age, sex, stage and response to treatment, the association of positive HPV status with improved survival remained (HR 0.24 [0.11-0.55] p < 0.001). High VL was associated with improved overall survival in the univariate analysis with a HR of 0.28 (0.11-0.71, p = 0.007). When adjusted only by age and sex, high VL was associated with better overall survival (HR 0.27, 0.11-0.68 p = 0.006).

CONCLUSIONS

HPV status appears to be independently associated with improved outcomes in anal cancer patients. Moreover, HPV viral load quantification may be informative for further risk stratification and warrants further investigation.

Low Prevalence of HPV Related Oropharyngeal Carcinogenesis in Northern Sardinia

HPV infection is a clear etiopathogenetic factor in oropharyngeal carcinogenesis and is associated with a markedly better prognosis than in smoking- and alcohol-associated cases, as specified by AJCC classification. The aim of the present work is to evaluate the prevalence of HPV-induced OPSCC in an insular area in the Mediterranean and to assess the reliability of p16 IHC (immunohistochemistry) alone, as accepted by AJCC, in the diagnosis of HPV-driven carcinogenesis in such a setting. All patients with OPSCC consecutively managed by the referral center in North Sardinia of head and neck tumor board of AOU Sassari, were recruited. Diagnosis of HPV-related OPCSS was carried out combining p16 IHC and DNA testing on FFPE samples and compared with the results of p16 IHC alone. Roughly 14% (9/62) of cases were positive for HPV-DNA and p16 IHC. Three more cases showed overexpression of p16, which has a 100% sensitivity, but only 75% specificity as standalone method for diagnosing HPV-driven carcinogenesis. The Cohen’s kappa coefficient of p16 IHC alone is 0.83 (excellent). However, if HPV-driven carcinogenesis diagnosed by p16 IHC alone was considered the criterion for treatment deintensification, 25% of p16 positive cases would have been wrongly submitted to deintensified treatment for tumors as aggressive as a p16 negative OPSCC. The currently accepted standard by AJCC (p16 IHC alone) harbors a high rate of false positive results, which appears risky for recommending treatment deintensification, and for this aim, in areas with a low prevalence of HPV-related OPSCC, it should be confirmed with HPV nucleic acid detection.

Identification of high protein kinase CK2α in HPV(+) oropharyngeal squamous cell carcinoma and correlation with clinical outcomes

Background

Oropharyngeal squamous cell carcinoma (OPSCC) incidence is rising worldwide, especially human papillomavirus (HPV)-associated disease. Historically, high levels of protein kinase CK2 were linked with poor outcomes in head and neck squamous cell carcinoma (HNSCC), without consideration of HPV status. This retrospective study examined tumor CK2α protein expression levels and related clinical outcomes in a cohort of Veteran OPSCC patient tumors which were determined to be predominantly HPV(+).

Methods

Patients at the Minneapolis VA Health Care System with newly diagnosed primary OPSCC from January 2005 to December 2015 were identified. A total of 119 OPSCC patient tumors were stained for CK2α, p16 and Ki-67 proteins and E6/E7 RNA. CK2α protein levels in tumors and correlations with HPV status and Ki-67 index were assessed. Overall survival (OS) analysis was performed stratified by CK2α protein score and separately by HPV status, followed by Cox regression controlling for smoking status. To strengthen the limited HPV(−) data, survival analysis for HPV(−) HNSCC patients in the publicly available The Cancer Genome Atlas (TCGA) PanCancer RNA-seq dataset was determined for CSNK2A1.

Results

The patients in the study population were all male and had a predominant history of tobacco and alcohol use. This cohort comprised 84 HPV(+) and 35 HPV(−) tumors. CK2α levels were higher in HPV(+) tumors compared to HPV(−) tumors. Higher CK2α scores positively correlated with higher Ki-67 index. OS improved with increasing CK2α score and separately OS was significantly better for those with HPV(+) as opposed to HPV(−) OPSCC. Both remained significant after controlling for smoking status. High CSNK2A1 mRNA levels from TCGA data associated with worse patient survival in HPV(−) HNSCC.

Conclusions

High CK2α protein levels are detected in HPV(+) OPSCC tumors and demonstrate an unexpected association with improved survival in a strongly HPV(+) OPSCC cohort. Worse survival outcomes for high CSNK2A1 mRNA levels in HPV(−) HNSCC are consistent with historical data. Given these surprising findings and the rising incidence of HPV(+) OPSCC, further study is needed to understand the biological roles of CK2 in HPV(+) and HPV(−) HNSCC and the potential utility for therapeutic targeting of CK2 in these two disease states.

Clinical relevance of CYFRA 21-1 as a tumour marker in patients with oropharyngeal squamous cell carcinoma

BACKGROUND

The role of Cytokeratin fraction 21-1 (CYFRA 21-1) as a tumour marker for head and neck cancer is still a matter of research. The aim of the present study was to evaluate the clinical impact of CYFRA 21-1 for patients with oropharyngeal squamous cell carcinoma (OSCC).

PATIENTS AND METHODS

Data of 180 patients with an initial diagnosis of OSCC of any stage between 2003 and 2017 were retrospectively analysed regarding the association between pretherapeutic CYFRA 21-1 levels, clinical characteristics, overall and disease-free survival. Additionally, the potential of CYFRA 21-1 for the detection of recurrent disease in the follow-up was evaluated. The cut-off value was set at 3.3 ng/ml. The median follow-up time was 2.85 years.

RESULTS

A significant correlation of the CYFRA 21-1 concentration at the time of diagnosis and the N-stage was detected (p = 0.01). Patients with CYFRA 21-1 levels > 3.3 ng/ml at first diagnosis showed a significantly shorter overall survival. In the case of disease-progression, a significant increase of CYFRA 21-1 value was found compared to post-therapeutic CYFRA 21-1 levels (9.1 ng/ml versus 5.1 ng/ml; p < 0.01). CYFRA 21-1 level after treatment showed only a low sensitivity of 32% and a specificity of 78% for tumour recurrence.

CONCLUSION

CYFRA 21-1 correlates with the tumour stage and, therefore, the survival of OSCC patients. Posttreatment CYFRA21-1 seems not to be a suitable predictor of tumour recurrence in the further course of the disease. However, a sudden increase of CYFRA 21-1 during follow-up may indicate a tumour recurrence in the individual patient.

Intralesional EBV-DNA load as marker of prognosis for nasopharyngeal cancer

Nasopharyngeal cancer (NPC) is associated with the Epstein-Barr virus (EBV). The clinical presentation and prognosis of NPC is well described, but not in relation to intralesional EBV-DNA load. In a retrospective design, 48 patients with NPC were examined. Patient history was re-evaluated, and diagnostic biopsies were re-examined. Furthermore, intralesional EBV-DNA was quantitated and HPV status determined. Cancer stage, disease-free survival (DFS), and overall survival (OS) were assessed. Of the 48 patients, 36 (75%) patients featured lesions that were positive for EBER (Epstein-Barr virus-encoded small RNA) and 40 (83%) were positive for EBV-DNA. Seven patients (15%) were HPV positive. The levels of EBV-DNA ranged from 0.0005 to 94617 copies/cell. An EBV-DNA load of more than 70 copies/cell was associated with a prolonged DFS for EBV-DNA positive patients treated with curative intent (p = 0.046). In conclusion, the EBV-DNA load in NPC lesions appears to vary greatly. For patients with EBV-DNA positive NPC treated with curative intent, an EBV-DNA load of more than 70 copies/cell is associated with a better outcome in terms of 7-year DFS.

Detection of circulating HPV16 DNA as a biomarker in the blood of patients with human papillomavirus-positive oropharyngeal squamous cell carcinoma

BACKGROUND

Development of biomarker analysis using the circulating cell-free DNA (cfDNA) methodology is a challenge for noninvasive cancer diagnosis. In this study, a comparison between the plasma and tumor tissue HPV16 DNA viral loads (VLs) has been presented.

METHODS

Real-time polymerase chain reaction was performed for quantitating of HPV16 DNA in the plasma and tumor samples of patients with oropharyngeal cancer.

RESULTS

Among the tissues, HPV16-positive patients with oropharyngeal squamous cell carcinoma, nonsmoking patients, displayed significantly higher HPV16 DNA VLs in their tissue. No smoking and advanced N disease were the most important predictors for cHPV16 DNA (circulating HPV16 DNA) detection. The cHPV16-positive women displayed significantly higher VLs in their tumor tissues compared to the men, although without notable impact on the blood detection.

CONCLUSIONS

Many factors were responsible for human papillomavirus DNA circulation in blood. As a result of the small size of the analyzed group, some observed discrepancies need to be proven on a larger cohort.

HPV-16 viral load in oropharyngeal squamous cell carcinoma using digital PCR

CONCLUSIONS

We did not identify any strong associations between HPV-16 viral load and any of the clinical or lifestyle factors.

OBJECTIVE

The epidemiology of oropharyngeal SCC is changing, with an increasing proportion of HPV-positive cases seen in the last decade. It is known that a high viral load is linked to the development of cervical cancer, the relation between viral load and oropharyngeal SCC is less clear. We sought to determine HPV-16 viral load in HPV-positive oropharyngeal SCCs using highly sensitive digital PCR and to identify clinical and lifestyle factors associated with viral load.

SUBJECTS AND METHODS

We analysed 45 HPV-16 positive oropharyngeal SCCs diagnosed between 2013 and 2015. All patients completed a lifestyle questionnaire and clinical data were extracted from medical charts. Viral load was determined using digital PCR assays for HPV-L1 and RNAseP.

RESULTS

We found large variations in HPV-16 viral load from 1 to 930 copies per cell (median 34 copies per cell).

Differences in the prognosis of HPV16-positive patients with squamous cell carcinoma of head and neck according to viral load and expression of P16

Purpose

To evaluate the impact of HPV16 load (VL—the number of virus genome copies per cell) and P16 expression on prognosis of patients with squamous cell carcinomas (SCCs) of head and neck (HN).

Materials and methods

HPV16 presence was assessed in the group of 109 patients with HNSCCs by quantitative polymerase chain reaction (qPCR). VL (assessed by qPCR) and P16 expression (evaluated by immunohistochemistry) were analysed only in the subgroup of HPV16-positive tumours. These features were correlated with 5-year overall survival (OS) and disease-free survival (DFS).

Results

HPV16 infection was found in 36 tumours (33.0%). Virus-positive patients had better OS and DFS than those without infection (P = 0.041 and 0.005). Among HPV16-positive HNSCCs, 18 (50.0%) had higher VL (median value > 6764.3 copies/cell) and 25 (73.5%) P16 over expression. The significant differences in OS and DFS (P = 0.008 and 0.004) were noticed according to VL, wherein 100% DFS was found for patients with higher VL. According to P16 expression, significant difference was found only for OS (P = 0.020). In multivariate analysis, VL (P = 0.045; HR = 2.795; CI 0.121–1.060) and the level of smoking (P = 0.023, HR = 2.253; CI 1.124–4.514) were independent factors affecting DFS of HPV16-positive patients.

Conclusion

On the basis of viral load, it is possible to differentiate prognosis of patients with HPV16-positive HNSCCs. In this subgroup, viral load has stronger prognostic potential than P16 expression.

Human papillomavirus in head and neck cancer in India: Current status and consensus recommendations

Human papillomavirus (HPV) associated head and neck squamous cell cancers (HNSCC) have become increasingly common in the West, but the same cannot be said about India. These cancers have a different biology and confer a better prognosis, however, its current role in the management of patients in India is not clearly defined. At the 35th Indian Cooperative Oncology Network conference held in September 2016, a panel of radiation, surgical and medical oncologists, pathologists, and basic scientists from across the country having experience in clinical research with respect to HPV in HNSCC reviewed the available literature from India. All the ideas and facts were thereafter collated in this report. Various topics of controversy in dealing with the diagnosis and management of HPV-associated HNSCC have been highlighted in this report in context to the Indian scenario. Furthermore, the prevalence of the same and its association with tobacco and high-risk sexual behavior has been touched on. Conclusively, a set of recommendations has been proposed by the panel to guide the practicing oncologists of the country while dealing with HPV-associated HNSCC.

Physical state and copy numbers of HPV16 in oral asymptomatic infections that persisted or cleared during the 6-year follow-up

Persistent human papillomavirus (HPV) infection is a key event in HPV-induced carcinogenesis. As part of the prospective Finnish Family HPV Study, we analysed the physical state and viral copy numbers of HPV16 in asymptomatic oral infections that either persisted or cleared during the 6-year follow-up. The persister group comprised 14 women and 7 men with 51 and 21 HPV16-positive brush samples. The clearance group included 41 women and 13 men, with 64 and 24 samples, respectively. Physical state and viral DNA load were assessed by using quantitative PCR for HPV16 E2 and E6 genes. E2/E6 ratio was calculated and HPV16 was classified as episomal, mixed or integrated with values of 0.93-1.08, <0.93 and 0, respectively. In both genders, the physical state of HPV16 was significantly different between the cases and controls (P<0.001). HPV16 was episomal in all men and 66 % (27/41) of women who cleared their infection. HPV16 was mixed and/or integrated in71 % and 57 %of the women and men persisters, respectively. The mean HPV16 copy number per 50 ng genomic DNA was nearly 5.5-fold higher in the women than in the men clearance group (P=0.011). Only in men, HPV16 copy numbers were higher in persisters than in the clearance group (P=0.039). To conclude, in both genders, persistent oral HPV16 infections were associated with the mixed or integrated form of HPV16, while in the clearance groups, episomal HPV16 predominated. This indicates that HPV16 integration is a common event even in asymptomatic oral infections, which might predispose the infected subjects to progressive disease.

Prevalence of HPV Infection in Racial-Ethnic Subgroups of Head and Neck Cancer Patients

The landscape of HPV infection in racial/ethnic subgroups of head and neck cancer (HNC) patients has not been evaluated carefully. In this study, a meta-analysis examined the prevalence of HPV in HNC patients of African ancestry. Additionally, a pooled analysis of subject-level data was also performed to investigate HPV prevalence and patterns of p16 (CDNK2A) expression amongst different racial groups. Eighteen publications (N = 798 Black HNC patients) were examined in the meta-analysis, and the pooled analysis included 29 datasets comprised of 3,129 HNC patients of diverse racial/ethnic background. The meta-analysis revealed that the prevalence of HPV16 was higher among Blacks with oropharyngeal cancer than Blacks with non-oropharyngeal cancer. However, there was great heterogeneity observed among studies (Q test P<0.0001). In the pooled analysis, after adjusting for each study, year of diagnosis, age, gender and smoking status, the prevalence of HPV16/18 in oropharyngeal cancer patients was highest in Whites (61.1%), followed by 58.0% in Blacks and 25.2% in Asians (P<0.0001). There was no statistically significant difference in HPV16/18 prevalence in non-oropharyngeal cancer by race (P=0.682). With regard to the pattern of HPV16/18 status and p16 expression, White patients had the highest proportion of HPV16/18+/p16+ oropharyngeal cancer (52.3%), while Asians and Blacks had significantly lower proportions (23.0% and 22.6%, respectively) [P <0.0001]. Our findings suggest that the pattern of HPV16/18 status and p16 expression in oropharyngeal cancer appears to differ by race and this may contribute to survival disparities.

Oral sex and oropharyngeal cancer: The role of the primary care physicians

BACKGROUND

We aimed to study the prevalence of oral sex and its possible association with human papillomavirus (HPV) 16 infection in the development of oropharyngeal cancer in the US population for possible prevention.

METHODS

We conduct a systemic review on the prevalence of oral sex among Americans among different age groups, the prevalence of HPV 16 infection reported in oropharyngeal cancer, and correlation between oral sex and oropharyngeal cancer.

RESULTS

Oral sex is prevalent among adolescents and sexually active adults. Sixty percent of oropharyngeal cancer reported in the United States is associated with HPV 16 infections. Individuals who practiced oral sex with multiple partners are at risk for developing oropharyngeal cancer and need to be informed about practicing safe sex or getting vaccination.

CONCLUSION

Family physicians will play a key role in prevention and educating the public about the risk of oral sex.

HPV-Positive Oropharyngeal Carcinoma

Objective

Human papillomavirus-positive (HPV+) head and neck squamous cell carcinoma is increasing in incidence and appears to exhibit improved response to treatment and better survival than that of HPV– head and neck squamous cell carcinoma. The purpose of this systematic review was to examine the current literature regarding treatment and prognosis of HPV+ oropharyngeal squamous cell carcinoma (OPSCC) and identify whether type of treatment (primarily surgery vs primarily radiation) significantly affects survival rates.

Data Sources

PubMed and Cochrane Library databases.

Review Methods

A computerized search of the PubMed and Cochrane Library databases was performed to identify English-language articles published between January 1, 2000, and October 21, 2014. Studies were included only if they were prospective or retrospective observational series of OPSCC patients that reported HPV status, treatment regimen, and survival outcomes. Outcomes were determined for HPV+ and HPV– OPSCC patients, with subanalyses according to the type of treatment received.

Results

Fifty-six articles were eligible for this review. In the HPV+ analysis, the unadjusted hazard rate ratio (HR) for surgery vs radiation treatment was 1.33 ( P = .114). Nine confounders were considered, and HRs were adjusted for each covariate. While HRs were almost all >1 for all covariates, none of the HRs was statistically significant at P < .05. The HR for HPV– OPSCC was higher for radiation than surgery.

Conclusions

HPV+ OPSCC has an improved prognosis and lower rates of adverse events when compared with HPV– OPSCC. HPV– OPSCC had significantly worse outcomes when treated with primary radiation as compared with primary surgery. There was no statistically significant difference in HRs for HPV+ OPSCC with primary radiation vs primary surgery treatment.

Detection of human papillomavirus (HPV) in clinical samples: evolving methods and strategies for the accurate determination of HPV status of head and neck carcinomas

Much recent attention has highlighted a subset of head and neck squamous cell carcinomas (HNSCCs) related to human papillomavirus (HPV) that has an epidemiologic, demographic, molecular and clinical profile which is distinct from non-HPV-related HNSCC. The clinical significance of detecting HPV in a HNSCC has resulted in a growing expectation for HPV testing of HNSCCs. Although the growing demand for routine testing is understandable and appropriate, it has impelled an undisciplined approach that has been largely unsystematic. The current state of the art has now arrived at a point where a better understanding of HPV-related tumorigenesis and a growing experience with HPV testing can now move wide scale, indiscriminant and non-standardized testing towards a more directed, clinically relevant and standardized approach. This review will address the current state of HPV detection; and will focus on why HPV testing is important, when HPV testing is appropriate, and how to test for the presence of HPV in various clinical samples. As no single test has been universally accepted as a best method, this review will consider the strengths and weaknesses of some of the more commonly used assays, and will emphasize some emerging techniques that may improve the efficiency of HPV testing of clinical samples including cytologic specimens.

Human papillomavirus 16/18 E7 viral loads predict distant metastasis in oral cavity squamous cell carcinoma

BACKGROUND

Human papillomaviruses (HPV) seem to be related to distant metastasis (DM) in advanced oral cavity squamous cell carcinoma (OSCC) patients.

OBJECTIVES

This study aimed to investigate whether high-risk HPV viral load may predict DM among OSCC patients and stratify patients for risk-adapted treatment.

STUDY DESIGN

Viral loads of E7 oncogenes for HPV 16/18 were measured by quantitative PCR tests in paraffin-embedded lesional specimens from 312 OSCC of which the HPV genotypes had been determined previously. Multivariable Cox regression analysis was used to identify the independent prognostic factors for 5-year DM and C statistics were further computed.

RESULTS

By multivariable analysis, high HPV 16 E7 viral load (≥15.0 copies/genome); high HPV 18 E7 viral load (≥15.0 copies/genome); pathological N2 status (pN2); tumor depth ≥11 mm; extracapsular spread (ECS); and level IV/V metastases were independent risk factors for DM. We further identified three prognostic groups. In the high-risk group (level IV/V metastases or high HPV 16/18 E7 viral load plus pN2, tumor depth ≥11 mm, or ECS), the 5-year distant metastasis rate was 74%. In the intermediate-risk group (high HPV 16/18 E7 viral load, pN2, tumor depth ≥11 mm, or ECS), the 5-year DM rate was 17%. Finally, the 5-year DM rate was 1% in the low-risk group (no risk factors). The value of the C statistics was 0.78.

CONCLUSIONS

Among OSCC patients, high HPV 16/18 E7 viral load identifies a small subgroup of patients at high-risk of 5-year DM and suggest the need for more intensive treatments and follow-up strategies.

Prevalence of human papillomavirus in oropharyngeal squamous cell carcinoma in the United States across time

Human papillomaviruses (HPVs) are involved in approximately 5% of all human cancer. Although initially recognized for causing nearly all cases of cervical carcinoma, much data has now emerged implicating HPVs as a causal factor in other anogenital cancers as well as a subset of head and neck squamous cell carcinomas (HNSCCs), most commonly oropharyngeal cancers. Numerous clinical trials have demonstrated that patients with HPV+ oropharyngeal squamous cell carcinoma (OPSCC) have improved survival compared to patients with HPV– cancers. Furthermore, epidemiological evidence shows the incidence of OPSCC has been steadily rising over time in the United States. It has been proposed that an increase in HPV-related OPSCCs is the driving force behind the increasing rate of OPSCC. Although some studies have revealed an increase in HPV+ head and neck malignancies over time in specific regions of the United States, there has not been a comprehensive study validating this trend across the entire country. Therefore, we undertook this meta-analysis to assess all literature through August 2013 that reported on the prevalence of HPV in OPSCC for patient populations within the United States. The results show an increase in the prevalence of HPV+ OPSCC from 20.9% in the pre-1990 time period to 51.4% in 1990–1999 and finally to 65.4% for 2000–present. In this manner, our study provides further evidence to support the hypothesis that HPV-associated OPSCCs are driving the increasing incidence of OPSCC over time in the United States.

Human papilloma virus testing in oropharyngeal squamous cell carcinoma: what the clinician should know

High risk Human Papilloma virus (HR-HPV) associated oropharyngeal cancers are on the increase. Although, the scientific community is aware of the importance of Human Papilloma Virus (HPV) testing, there is no consensus on the assays that are required to reliably identify HR-HPV related tumors. A wide range of methods have been developed. The most widely used techniques include viral DNA detection, with polymerase chain reaction (PCR) or In Situ Hybridization, and p16 detected by immunohistochemistry. However, these tests provide different information and have their own specific limitations. In this review, we summarize these different techniques, in light of the recent literature. p16 Overexpression, which is an indirect marker of HPV infection, is considered by many head and neck oncologists to be the most important marker for patient stratification. We describe the frequent lack of concordance of this marker with other assays and the possible reasons for this. The latest developments in HPV testing are also reported, such as the RNAscope™ HPV test, and how they fit into the existing framework of techniques. HPV testing must not be considered in isolation, as there are important interactions with other parameters, such as tobacco exposure. This is an important and rapidly evolving field and is likely to become pivotal to staging and choice of treatment of oropharyngeal carcinoma in the future.

The clinical impact of HPV tumor status upon head and neck squamous cell carcinomas

Human papillomavirus (HPV) is etiologically responsible for a distinct subset of head and neck squamous cell cancers (HNSCCs). HPV-positive HNSCCs (HPV-HNSCCs) most commonly arise from the oropharynx and are responsible for the increasing incidence of oropharyngeal SCC (OSCC) in the United States (US) and abroad. HPV-positive OSCC (HPV-OSCC) has a unique demographic and risk factor profile and tumor biology. HPV-OSCC patients tend to be white, younger, and have a higher cumulative exposure to sexual behaviors as compared with HPV-negative OSCC patients. HPV-positive tumor status also significantly improves survival, and is indeed the single strongest prognostic factor for OSCC. The mechanisms that underlie the improved prognosis conferred by HPV-positive disease are unknown. The purpose of this review is to describe the clinical impact of HPV status in HNSCC, particularly in OSCC, both in terms of the unique clinic-demographic profile and prognostic implications.

Next-generation sequencing for simultaneous determination of human papillomavirus load, subtype, and associated genomic copy number changes in tumors

Human papillomavirus (HPV) infection in cases of squamous cell carcinoma of the oropharynx is a powerful predictive and prognostic biomarker. We describe how the use of next-generation sequencing can provide a novel method for the detection of HPV in DNA isolated from formalin-fixed paraffin-embedded tissues. Using this methodology in a cohort of 44 head and neck tumors, we identified the samples that contained HPV sequences, the viral subtype involved, and a direct readout of viral load. Specificity of HPV detection by sequencing compared to traditional detection methods using either PCR or p16 immunohistochemistry was 100%. Sensitivity was 50% when either compared to PCR [confidence interval (CI) = 29% to 71%] or 75% when compared to p16 (CI = 47% to 91%). In addition, we demonstrate the ability of next-generation sequencing to detect other HPV subtypes that would not have been detected by traditional methods, and we demonstrated the ability to apply this method to any tumor and any virus in a panel of eight human cancer cell lines. This methodology also provides a tumor genomic copy number karyogram, and in the samples analyzed here, a lower level of chromosome instability was detected in HPV-positive tumors compared to HPV-negative tumors, as observed in previous studies. Thus, the use of next-generation sequencing for the detection of HPV provides a multiplicity of data with clinical significance in a single test.

Human Papillomavirus in Metastatic Lymph Nodes from Unknown Primary Head and Neck Squamous Cell Carcinoma

Objective. Determine human papillomavirus (HPV) incidence in unknown primary squamous cell carcinomas (SCCa) of the head and neck and assess if HPV status influenced survival.

Study Design. Historical cohort study.

Setting. Tertiary care center.

Subjects. Patients with unknown primary SCCa despite a complete workup who underwent neck dissection or excisional biopsy and postoperative comprehensive ± chemoradiotherapy between 2002 and 2009.

Methods. HPV fluorescence in situ hybridization (FISH) and p16INK4a immunohistochemistry (p16 IHC) were performed. Results were compared with survival, age, race, gender, tobacco use, alcohol use, and nodal stage.

Results. Twenty-five patients met the inclusion criteria, of whom 88% were >10 pack year tobacco users. Twenty-eight percent were HPV positive defined by both p16+ and FISH+. Five-year overall survival was 66.7% in HPV-positive and 48.5% in HPV-negative patients ( P = .35). Similarly, 5-year disease-free survival rates were 66.7% in HPV-positive and 48.5% in HPV-negative patients ( P = .54). All 3 HPV-positive nonsmokers were survivors, but this was not significant because of the small sample size ( P > .05). No other characteristics were associated with survival ( P > .05).

Conclusion. Twenty-eight percent of metastatic lymph nodes from occult primary tumors were HPV positive. There was no survival difference associated with HPV status. Most of the HPV-positive patients in this study were tobacco users who had similar survival to HPV-negative patients, so caution should be used in interpreting HPV status in these patients.

Characterization of the methylation patterns in human papillomavirus type 16 viral DNA in head and neck cancers

Human papillomavirus (HPV) type 16 can integrate into the host genome, thereby rendering the viral coding genes susceptible to epigenetic modification. Using bisulfite genomic sequencing, we determined the methylation status of all 110 CpG sites within the viral epigenome in advanced stage III/IV HPV-16-associated head and neck cancers. We found that the viral genome was hypomethylated in the majority of head and neck cancers, in particular within the viral regulatory region, long control region (LCR), which controls transcription of the E6 and E7 oncogenes. The hypomethylation status of LCR correlated with detectable levels of E6 and E7 expression, which suggests that the tumors may still be dependent on these viral oncogenes to maintain the malignant phenotype. In addition to the methylation status of LCR, we report other potential factors which may influence intratumoral E6 and E7 expression including viral copy number and integration site. We were able to detect the viral epigenetic alterations in sampled body fluids, such as serum and saliva, which correlated with the changes observed in the primary tumors. Because viral epigenetic changes occur in the setting of viral integration into the human genome, the detection of methylated HPV genes in the serum and/or saliva may have diagnostic potential for early detection strategies of viral integration and assessment of risk for cancer development in high-risk individuals. Our findings also support continued targeting of the E6 and/or E7 antigens through various vaccine strategies against HPV-associated cancers.

Human papillomavirus detection in head and neck squamous cell carcinomas

Squamous cell carcinomas of the head and neck (HNSCC) are a frequent diagnosis in anatomic pathology practice. Tobacco use and heavy alcohol consumption are known risk factors for HNSCC but in other cases human papillomavirus (HPV) is linked to carcinogenesis. HPV proteins E6 and E7 promote oncogenesis by blocking the action of p53 and pRB, respectively. An absence of p53 mutations in addition to expression of p16 are part of the distinct molecular profile identified in the subset of HNSCCs because of HPV. Various methods are available for HPV detection but polymerase chain reaction and in situ hybridization techniques are commonly used. Both methods are amenable for testing formalin-fixed paraffin-embedded tissue that is a sample type readily available to the pathologist. HPV is detectable in approximately a quarter of all HNSCCs, and is particularly prevalent in the oropharynx in which the positivity rates approach 40%. A vast majority of HPV-related HNSCCs are owing to HPV type 16 with types 18, 31, and 33 accounting for almost all of the remaining cases. HPV-related HNSCCs are associated with better prognosis for both recurrence and survival. This group of tumors has also been shown to respond well to radiation treatment. As the clinical relevance of HPV in HNSCCs continues to emerge, anatomic pathologists are likely to receive increasing requests for testing. Herein, the authors review the biological and clinical aspects of HPV-associated HNSCC and review techniques for HPV detection.

Vaccination against human papilloma virus (HPV): epidemiological evidence of HPV in non-genital cancers

Recently, the vaccine against human papillomavirus (HPV) was introduced in the national vaccination programmes of several countries worldwide. The established association between HPV and the progression of cervical neoplasia provides evidence of the expected protection of the vaccine against cervical cancer. During the last two decades several studies have also examined the possible involvement of HPV in non-genital cancers and have proposed the presence of HPV in oesophageal, laryngeal, oropharyngeal, lung, urothelial, breast and colon cancers. The possible involvement of HPV in these types of cancer would necessitate the introduction of the vaccine in both boys and girls. However, the role of HPV in the pathogenesis of these types of cancer has yet to be proven. Moreover, the controversial evidence of the possible impact of the vaccination against HPV in the prevention of non-genital cancers needs to be further evaluated. In this review, we present an overview of the existing epidemiological evidence regarding the detection of HPV in non-genital cancers.

Polymerase chain reaction detection of HPV in squamous carcinoma of the oropharynx

Human papillomavirus (HPV) testing is routinely performed on oropharyngeal carcinomas. We compared the Access Genetics (Minneapolis, MN) polymerase chain reaction (PCR) assay (AGPCR), DNA-DNA in situ hybridization (ISH; Ventana, Tucson, AZ), and HPV-16 E7 PCR amplification in consecutively accessioned oropharyngeal cancers. We tested 126 cases by both PCR methods; 102 were positive by either for a maximum positive rate (MPR) of 81.0%. Relative to the MPR, the sensitivities of AGPCR and E7 PCR were 90.2% and 72.5%, respectively. Of 17 AGPCR+ cases tested by ISH, 14/14 unequivocally positive/negative were concordant. All cases (97/97) positive by either PCR assay were positive for p16. There was no relationship between level of histologic differentiation and HPV status. ISH and AGPCR have comparable performance for the detection of HPV in oropharyngeal carcinomas. PCR is a suitable and economical assay that is comparable to ISH in sensitivity and may provide logistical advantages relative to ISH for assessing HPV status in oropharyngeal malignancies. However, it is imperative that appropriate sensitivity controls be in place for such assays.

Meta-analysis of the impact of human papillomavirus (HPV) on cancer risk and overall survival in head and neck squamous cell carcinomas (HNSCC)

BACKGROUND

HPV is important in a subset of HNSCC. Our meta-analysis determined the clinical characteristics of HPV-related HNSCC.

METHOD

Pubmed search terms "HPV" and "HNSCC" were used to identify 34 studies since 1980. We obtained pooled adjusted odds ratio (OR) or hazard ratio (HR) using random or fixed-effects model and compared OS depicted in forest plot.

RESULTS

A total of 5681 patients were included. The prevalence of HPV+ tumors was 22%, with 86.7% of HPV16+ genotype. The OR for HNSCC in HPV16+ patients was 4.44 (95% CI = 2.87-6.02). HPV status was associated with p16 expression (adj OR = 3.00; 0.90-9.70), and HPV+ tumors were less likely to harbor p53 mutations (adj OR = 0.21; 0.04-0.38). The HR for death in HPV+ patients was 0.42 (0.27-0.57). HPV+ HNSCC also had a better response to therapy.

CONCLUSION

HPV+ HNSCC are established as a separate biologic entity. Prospective trials are needed to establish the optimal therapy for HPV+ HNSCC.

Human papillomavirus-associated oropharyngeal cancer: a new clinical entity

The incidence of oropharyngeal cancers is rising worldwide in both nonsmokers and nondrinkers. Epidemiology studies suggest a strong association between human papillomavirus (HPV) 16 infection, changing sexual behavior and cancer development. Despite initial presentation with locally advanced disease and poorly differentiated histology, HPV-associated oropharyngeal carcinoma is associated with a good prognosis because its response to chemotherapy and radiation. Clinicians should be aware of the risk of oropharyngeal cancer in young people to avoid unnecessary delay in diagnosis and treatment. A history of oral sex should be elicited in young patients with enlarged neck nodes and/or tonsillar masses.

HPV status in head and neck tumors

HPV infection has been associated with head and neck carcinoma (HNSCC). In the present study, a tumor collective from Middle Germany was analyzed using two HPV-detection methods, i.e., PCR followed by agarose gel electrophoresis and microarray chip hybridization. In addition, the predictive value of tumor morphology was assessed. In total, 76 HNSCCs from 52 patients were examined, including 23 pairs of primaries and corresponding metastases. The highest rate of positive tumors was observed in the tonsils, with 76% of the patients and 81% of tumor samples being positive for high-risk HPV. DNA chip analysis detected significantly more HPV-positive cases than did agarose gel electrophoresis. Except for one HPV-33-positive case, all others tumors harbored HPV 16. There was a good concordance between the HPV status of the primary tumor and its corresponding metastasis (21/23 cases, 91%). In two cases, HPV was found only in the primary tumor but not in the metastasis. Our results clearly confirmed the high prevalence of HR-HPV in tonsillar carcinomas with a rate that was even 20% higher than those reported in the literature. Morphology is a valuable indicator for an HPV association that needs to be confirmed by molecular tests.

A new multiparameter assay to assess HPV 16/18, viral load and physical status together with gain of telomerase genes in HPV-related cancers

Oncogenic human papillomavirus (HPV) is the most important risk factor for cancer of the uterine cervix and a subgroup of head and neck cancers. Viral load has been associated with persistence of infection, whereas integration of HPV into the host cell genome is associated with transition to invasive disease. Viral integration is frequently correlated with loss of viral E2 and gain of the telomerase-related genes TERC and TERT. The objective of this study was to develop a rapid and sensitive multiplex ligation-dependent probe amplification (MLPA) assay for the simultaneous analysis of viral load, integration and copy number gain of TERC and TERT in HPV16/18-associated lesions. The performance of the assay was tested for HPV vs. human gene copy number ratios ranging from 0.1 to 100 and for percentages of integration ranging from 0 to 100%. The model systems used include plasmid mixtures and the HPV-positive cell lines SiHa, HeLa and CaSki described to contain a range of 2-600 viral copies per cell. In samples with low-viral load, viral integration can be reliably determined when more than 30% of the virus is integrated. Gain of the telomerase-related genes in the cell lines as determined by our MLPA assay was in accordance with data reported in the literature. Our study demonstrates that within a single MLPA-reaction viral type, load, integration and gain of TERC and TERT can be reliably determined, which will improve risk assessment for patients suspected for HPV infection.

Development and evaluation of a PCR and mass spectroscopy (PCR-MS)-based method for quantitative, type-specific detection of human papillomavirus

Knowledge of the central role of high-risk human papillomavirus (HPV) in cervical carcinogenesis, coupled with an emerging need to monitor the efficacy of newly introduced HPV vaccines, warrant development and evaluation of type-specific, quantitative HPV detection methods. In the present study, a prototype PCR and mass spectroscopy (PCR-MS)-based method to detect and quantitate 13 high-risk HPV types is compared to the Hybrid Capture 2 High-Risk HPV DNA test (HC2; Digene Corp., Gaithersburg, MD) in 199 cervical scraping samples and to DNA sequencing in 77 cervical tumor samples. High-risk HPV types were detected in 76/77 (98.7%) cervical tumor samples by PCR-MS. Degenerate and type-specific sequencing confirmed the types detected by PCR-MS. In 199 cervical scraping samples, all 13 HPV types were detected by PCR-MS. Eighteen (14.5%) of 124 cervical scraping samples that were positive for high-risk HPV by HC2 were negative by PCR-MS. In all these cases, degenerate DNA sequencing failed to detect any of the 13 high-risk HPV types. Nearly half (46.7%) of the 75 cervical scraping samples that were negative for high-risk HPV by the HC2 assay were positive by PCR-MS. Type-specific sequencing in a subset of these samples confirmed the HPV type detected by PCR-MS. Quantitative PCR-MS results demonstrated that 11/75 (14.7%) samples contained as much HPV copies/cell as HC2-positive samples. These findings suggest that this prototype PCR-MS assay performs at least as well as HC2 for HPV detection, while offering the additional, unique advantages of type-specific identification and quantitation. Further validation work is underway to define clinically meaningful HPV detection thresholds and to evaluate the potential clinical application of future generations of the PCR-MS assay.