New evidence for geographic variation in the role of human papillomavirus in tonsillar carcinogenesis

Understanding the impact of high-risk human papillomavirus on oropharyngeal squamous cell carcinomas in Taiwan: A retrospective cohort study

BACKGROUND AND OBJECTIVES

Human papillomavirus (HPV)-driven oropharyngeal squamous cell carcinoma (OPSCC) is increasing globally. In Taiwan, HPV-positive OPSCC is obscured by tobacco, alcohol, and betel quid use. We investigated the role of high-risk HPV (hrHPV) in a large retrospective Taiwan OPSCC cohort.

METHODS AND RESULTS

The cohort of 541 OPSCCs treated at Chang Gung Memorial Hospital from 1998-2016 consisted of 507 men (94%) and 34 women (6%). Most used tobacco (81%), alcohol (51%), and betel quid (65%). Formalin-fixed, paraffin-embedded tissue was used for p16 staining (a surrogate marker for HPV) and testing for HPV DNA presence and type by Multiplex HPV PCR-MassArray. HPV DNA and/or p16 staining (HPV-positive) was found in 28.4% (150/528) tumors. p16 and HPV DNA were strongly correlated (F < 0.0001). HPV16 was present in 82.8%, and HPV58 in 7.5% of HPV-positive tumors. HPV was associated with higher age (55.5 vs. 52.7 years, p = 0.004), lower T-stage (p = 0.008) better overall survival (OS) (hazard ratio [HR] 0.58 [95% CI 0.42-0.81], p = 0.001), and disease-free survival (DFS) (HR 0.54 [95% CI 0.40-0.73], p < 0.0001). Alcohol was strongly associated with recurrence and death (OS: HR 2.06 [95% CI 1.54-2.74], p < 0.0001; DFS: HR 1.72 [95% CI 1.33-2.24], p < 0.0001). OS and DFS in HPV-positive cases decreased for alcohol users (p < 0.0001). Obscured by the strong alcohol effect, predictive associations were not found for tobacco or betel quid.

CONCLUSIONS

As with HPV-positive OPSCC globally, HPV is an increasingly important etiological factor in Taiwanese OPSCC. HPV-positive OPSCC has considerable survival benefit, but this is reduced by alcohol, tobacco, and betel quid use. hrHPV is a cancer risk factor in males and females. Vaccinating both sexes with a multivalent vaccine including HPV58, combined with alcohol and tobacco cessation policies will be effective cancer-prevention public health strategies in Taiwan.

Immunohistochemical biomarkers and volumetric parameters for predicting radiotherapy-based outcomes in patients with p16-negative pharyngeal cancer

Background

This study determined the prognostic effects of immunohistochemical biomarkers and volumetric parameters predicting radiotherapy-based treatment in patients with p16-negative squamous cell carcinoma of the oropharynx or hypopharynx.

Results

VEGF immunoreactivity > 2 and GLUT1 overexpression were prognostic factors for lower cause-specific survival. Moreover, both factors were associated with lower disease-free survival. The predictors of lower primary relapse-free survival were VEGF immunoreactivity > 2 and CT-based gross tumor volume > 16 mL.

Materials and Methods

Immunohistochemical biomarkers in pretreatment biopsy specimens from 60 patients with p16-negative cancer were analyzed using tissue microarrays. Computed tomography (CT)-based and biological tumor volumes were retrieved through fluorodeoxyglucose positron emission tomography-CT. Correlations of cause-specific, disease-free, and primary relapse-free survival with volumetric parameters and the immunohistochemical biomarker score were investigated.

Conclusions

For patients with p16-negative pharyngeal cancer receiving radiotherapy, treatment outcomes can be stratified by VEGF and GLUT1 expression and CT-based gross tumor volume.

Differences in survival outcome between oropharyngeal and oral cavity squamous cell carcinoma in relation to HPV status

BACKGROUND

This study examined the prognostic significance of human papillomavirus (HPV) in patients with oropharyngeal and oral cavity squamous cell carcinoma (SCC).

METHODS

Tissue microarrays were constructed from oropharyngeal and oral cavity SCC (n = 143). The presence of functional HPV in tumour was determined by combined assessments of p16 immunohistochemistry and HPV in situ hybridisation.

RESULTS

Oropharyngeal SCC patients presented with more advanced disease in comparison with oral cavity SCC patients (P = 0.001). HPV is present in 60% and 61% of oropharyngeal and oral cavity SCC patients, respectively. HPV-positive oropharyngeal SCC patients with advanced TNM stages displayed better overall and disease-free survival outcomes than HPV-negative patients (P = 0.022 and 0.046, respectively). Such survival differences were not observed in oral cavity SCC.

CONCLUSIONS

HPV is common in both oropharyngeal and oral cavity SCC and is associated with better survival outcome in oropharyngeal SCC but not in oral cavity SCC patients.

Prevalence, Clinicopathological Characteristics, and Outcome of Human Papillomavirus-Associated Oropharyngeal Cancer in Southern Chinese Patients

BACKGROUND

Although the global incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) is increasing, there is little information on southern Chinese population available.

METHODS

We analyzed 207 patients which constituted 63.5% of all newly diagnosed OPSCC in Hong Kong during a 5-year period from 2005 to 2009.

RESULTS

We used E6/7 mRNA as a marker of oncogenic involvement and found 20.8% (43/207) of OPSCC and 29.0% (36/124) of tonsillar SCC was associated with HPV. HPV-16 was identified in all cases except one (HPV-18). Patients with HPV-associated OPSCCs were significantly younger than HPV-negative patients (mean age: 59.8 vs. 63.9 years, P = 0.05). Multivariate analysis showed that HPV-associated OPSCC was more likely to occur in nonsmokers (39.5% vs. 15.1%, OR: 2.89, P = 0.05), nondrinkers (52.5% vs. 25.6%, OR: 2.72, P = 0.04), originate from the palatine tonsils (83.7% vs. 53.7%, OR: 3.88, P = 0.01), present with an early primary tumor (T1/2; 79.1% vs. 47.6%, OR: 3.81, P = 0.004), and exhibit basaloid differentiation (33.3% vs. 7.3%, OR: 19.74, P = 0.006). HPV positivity was an independent predictor for better prognosis for both 5-year overall and 5-year disease-specific survivals (DSS; 63.0% vs. 29.7%, HR: 0.33, P < 0.001, and 87.8% vs. 42.6%, HR: 0.16, P < 0.001, respectively).

CONCLUSION

The estimated age-standardized incidence of OPSCC in Hong Kong during the period 2005-2009 was 0.12/100,000/year.

IMPACT

This study has provided the most comprehensive clinical and pathologic information to date about this newly recognized disease in southern Chinese. In view of the global trend, we should anticipate and prepare for an increase in HPV-related OPSCC in southern China.

HPV-associated head and neck cancers in the Asia Pacific: A critical literature review & meta-analysis

BACKGROUND

Malignancies of the upper aero-digestive tract are a major public health problem, especially in the Asia Pacific. Certain Human papillomaviruses (HPVs) are well-established risk factors for carcinoma of the uterine cervix and for a subset of head and neck carcinomata: however their true importance in different populations and anatomical subsites remains unclear. The major risk factors in Asia Pacific remain smoked/smokeless tobacco, areca nut, alcohol abuse and poor diet, with limited evidence for HPVs. We review published studies of association of HPV with anatomical site-specific Head & Neck Squamous Cell Carcinoma (HNSCC) in these populations and attempt a meta-analysis.

MATERIALS AND METHODS

From MEDLINE/PubMed/WEB-of SCIENCE/EMBASE/Scopus databases we found 67 relevant studies with a total of 7280 cases: 15 case-control studies met our inclusion criteria for meta-analysis, totaling 1106 cases & 638 controls. HPV detection rates, sample site and size, and methods of tissue preservation and HPV detection were tabulated for each study.

RESULTS

Studies were heterogeneous in terms of sample selection and method of detection of HPVs. Most were of limited quality. Averaging data from 67 studies of HNSCC, the prevalence of HPV of any subtype is approximately 36%. PCR (polymerase chain reaction) was the most used detection method and HPV16 the most common genotype reported. Meta-analyses of case-control studies from this region reveal significant heterogeneity but suggest higher HPV prevalence in oropharyngeal cancer (OR: 14.66; 95%CI: 6.09-35.26) compared to oral cavity cancer and laryngeal cancer; (OR: 4.06; 95%CI: 3.05-5.39 & OR: 3.23; 95%CI: 1.37-7.61) respectively.

CONCLUSION

In view of the significant association of HPV with HNSCC, studies with accurate subsite classification and more sensitive detection methods are necessary. Accurate data from this geographical region are essential to inform public health policies and treatment decisions, especially as studies from Europe and North America reveal HPV-driven cancers to be less aggressive, permitting treatment de-intensification.

Interactions between clinical factors, p16, and cyclin-D1 expression and survival outcomes in oropharyngeal and hypopharyngeal squamous cell carcinoma

BACKGROUND

P16 and cyclin-D1 are cell cycle proteins commonly dysregulated in head and neck carcinoma. We assessed their expression, clinicopathological variables, and overall survival (OS) in oropharyngeal and hypopharyngeal squamous cell carcinoma (SCC).

METHODS

Clinical characteristics and p16 and cyclin-D1 expression were evaluated in 101 patients with oropharyngeal SCC and 75 patients with hypopharyngeal SCC. Associations with OS were assessed using Cox regression and Kaplan-Meier analysis.

RESULTS

Compared to oropharyngeal SCC, patients with hypopharyngeal SCC were older, men, ever-smokers with higher mean Charlson Comorbidity Index (CCI), lower p16 expression, and poorer median OS (24.8 vs 62.3 months; p < .01). In oropharyngeal SCC, CCI (p < .001), cyclin-D1 (hazard ratio [HR] = 3.55; p = .007), current smoking (HR = 5.72; p = .004), and former smoking (HR = 4.12; p = .035) were independently associated with OS. In hypopharyngeal SCC, only nodal and Eastern Cooperative Oncology Group status were associated with OS.

CONCLUSION

In oropharyngeal SCC, cyclin-D1 expression is correlated with survival, whereas smoking status and CCI may allow further stratification of outcome.

Correlation between human papillomavirus and p16 overexpression in oropharyngeal tumours: a systematic review

Background:

A significant proportion of squamous cell carcinomas of the oropharynx (OP-SCC) are related to human papillomavirus (HPV) infection and p16 overexpression. This subgroup proves better prognosis and survival but no evidence exists on the correlation between HPV and p16 overexpression based on diagnostic measures and definition of p16 overexpression. We evaluated means of p16 and HPV diagnostics, and quantified overexpression of p16 in HPV-positive and -negative OP-SCCs by mode of immunohistochemical staining of carcinoma cells.

Methods:

PubMed, Embase, and the Cochrane Library were searched from 1980 until October 2012. We applied the following inclusion criteria: a minimum of 20 cases of site-specific OP-SCCs, and HPV and p16 results present. Studies were categorised into three groups based on their definition of p16 overexpression: verbal definition, nuclear and cytoplasmatic staining between 5 and 69%, and ⩾70% staining.

Results:

We identified 39 studies with available outcome data (n=3926): 22 studies (n=1980) used PCR, 6 studies (n=688) used ISH, and 11 studies (n=1258) used both PCR and ISH for HPV diagnostics. The methods showed similar HPV-positive results. Overall, 52.5% of the cases (n=2062) were HPV positive. As to p16 overexpression, 17 studies (n=1684) used a minimum of 5–69% staining, and 7 studies (n=764) used ⩾70% staining. Fifteen studies (n=1478) referred to a verbal definition. Studies showed high heterogeneity in diagnostics of HPV and definition of p16. The correlation between HPV positivity and p16 overexpression proved best numerically in the group applying ⩾70% staining for p16 overexpression. The group with verbal definitions had a significantly lower false-positive rate, but along with the group applying 5–69% staining showed a worse sensitivity compared with ⩾70% staining.

Conclusions:

There are substantial differences in how studies diagnose HPV and define p16 overexpression. Numerically, p16 staining is better to predict the presence of HPV (i.e. larger sensitivity), when the cutoff is set at ⩾70% of cytoplasmatic and nuclear staining.

Prevalence and trends of human papillomavirus in oropharyngeal cancer in a predominantly north Indian population

BACKGROUND

Human papillomavirus (HPV) prevalence in oropharyngeal squamous cell cancer (SCC) remains variable and studies have estimated that up to 60% may be positive.

METHODS

One hundred five treatment-naïve oropharyngeal SCC patients were included. HPV genotyping was done by consensus polymerase chain reaction (PCR) and reverse line-blot hybridization assay. HPV prevalence was co-related with sex, age, tobacco consumption, alcohol use, and high-risk sexual behavior.

RESULTS

HPV prevalence was 22.8%. No significant associations were seen between tobacco or alcohol consumption with HPV status. The mean number of lifetime sexual partners and indulgence in high-risk sexual behavior was significantly more in patients who are HPV positive. There were no significant associations between the 2 groups with respect to the stage of the tumor.

CONCLUSION

Results of this study confirms that patients who are HPV positive are younger, and with high-risk sexual behavior. We did not find any impact of smoking and alcohol consumption on HPV status.

Human papillomavirus and head and neck cancer

An increasing subset of patients with head and neck squamous cell carcinoma (HNSCCA) is positive for high-risk human papillomavirus (HR-HPV). Patients tend to be younger, have a minimal or absent tobacco and ethanol abuse history, increased number of lifetime sexual partners (particularly oral-genital sex), and squamous cell carcinomas (SCCAs) arising in the oropharynx. The most common HR-HPV associated with HNSCCA is HPV-16. HR-HPV positivity is associated with decreased expression of the p53 and Rb genes, overexpression of p16, decreased expression of EGFR, and a different genetic expression pattern compared with patients with HR-HPV-negative SCCAs, leading to the conclusion that this is a distinct clinical entity. Patients who have HR-HPV-positive HNSCCAs have an improved prognosis, particularly those with oropharyngeal SCCAs, leading some to speculate that the intensity of treatment might be decreased. At present, whether this can be done safely remains unclear.

The Prognostic Role of p16 Expression in Tonsil Cancer Treated by Either Surgery or Radiation

Objectives

Although human papillomavirus (HPV) infection is considered as a favorable prognostic factor in oropharyngeal cancer, the prognosis of HPV-associated tonsil cancer has rarely been studied especially when surgery was the main treatment. In this study, the authors investigated the effect of p16 over-expression (HPV infection) on tonsil cancer prognosis according to the type of treatment, HPV presence by PCR, and expression of p53 and epidermal growth factor receptor (EGFR) by immunohistochemistry (IHC).

Methods

Medical records of 33 tonsil cancer patients were reviewed. Using formalin-fixed and paraffin-embedded tumor specimens, PCR-based genotyping of HPV and IHC of p16, p53 and EGFR were performed. The effects of HPV presence and the expression of IHC markers were analyzed on the recurrence-free survival. Five-year disease-free survival (DFS) rates were evaluated according to p16 expression status.

Results

An over-expression of p16 was observed in 27 (81.9%) out of 33 cases. Surgery-based treatment was provided for 21 (63.6%) patients. There was no association between p16 immunoreactivity and HPV presence, nor with p53 and EGFR expression. Regardless of main treatment modalities, five-year DFS did not differ by p16 expression status (P=0.051). However, over-expression of p16 was associated with a lower recurrence in multivariable analyses (P=0.046).

Conclusion

Regardless of main treatment modalities, an over-expression of p16 (HPV infection) is associated with a lower recurrence in tonsil cancers. However it is not associated with simple HPV presence or p53 and EGFR over-expression.

Prevalence and clinical features of human papillomavirus in head and neck squamous cell carcinoma in Okinawa, southern Japan

Previous studies from Okinawa, a subtropical island in southern Japan, demonstrated a higher prevalence of human papillomavirus (HPV) in oral carcinoma and a higher incidence of oral and pharyngeal carcinoma than those for mainland Japan. The present study aims to investigate epidemiologic and clinical features of HPV in head and neck squamous cell carcinoma (HNSCC) in Okinawa. A total of 150 DNA samples from 150 Okinawan patients with head and neck squamous cell carcinoma (HNSCC) were screened for HPV sequences by PCR using three consensus primer sets, and HPV types were determined by direct sequencing. The samples were consisted of 46 cases from the hypopharynx, 44 from the oropharynx, 16 from the larynx, 25 from the oral cavity, 10 from the maxillary sinus, and 9 from the nasopharynx. HPV DNA was detected in 45 (30.0%) HNSCCs, and HPV-16 was identified in 86.7% of positive specimens. The highest prevalence of the HPV sequence was found in oropharyngeal carcinomas (50.0%), especially in tonsillar cancer (63.6%). Multivariate analysis showed that oropharyngeal carcinoma (P = 0.002; OR = 5.34; 95% CI = 1.83-15.58), oral cavity carcinoma (P = 0.012; OR = 4.94; 95% CI = 1.43-17.10), and histological poor differentiation (P = 0.011; OR = 4.25; 95% CI = 1.39-13.04) each independently increased the prevalence of HPV infection. The present study reveals that patients with HNSCC, e.g., oropharyngeal and oral cavity carcinomas, in Okinawa have relatively high HPV-16 positive rates and low HPV-18 positive rates comparing with mainland Japan.

Clinical heterogeneity and tumor control probability

Heterogeneity in tumor sensitivity to therapy within patient populations is a major factor affecting tumor control probability (TCP) models, typically flattening dose-response curves. Knowledge of the major clinical factors affecting TCP would allow incorporation of these factors into TCP models, or stratification of patients and tumors, yielding steeper and more specific and predictive TCP curves.

METHODS

Literature review of the results of therapy for oropharyngeal cancer.

RESULTS

In recent years an improvement in control rates of cancers such as oropharyngeal cancer has been reported as potentially gained due to the dosimetric superiority of intensity modulated radiotherapy (IMRT). However, the emergence of Human Papilloma Virus (HPV)-related oropharyngeal cancer in recent years is an example of a major clinical factor which likely supersedes the dosimetric gains of IMRT.

CONCLUSIONS

Clinical factors such as the example discussed in this paper: HPV-related oropharyngeal cancer, must be taken into account in TCP models in order for such models to be relevant.

Human papillomavirus predicts outcome in oropharyngeal cancer in patients treated primarily with surgery or radiation therapy

Objective:

This study examines the prognostic significance of human papillomavirus (HPV) in patients with locally advanced oropharyngeal squamous cell carcinoma (SCC) treated primarily with surgery or definitive radiotherapy.

Methods:

One hundred and ninety-eight patients with Stage 3/4 SCC were followed up for recurrence in any form or death from any cause for between 1 and 235 months after diagnosis. HPV status was determined using HPV E6-targeted multiplex real-time PCR/p16 immunohistochemistry. Determinants of recurrence and mortality hazards were modelled using Cox's regression with censoring at follow-up dates.

Results:

Forty-two per cent of cancers were HPV-positive (87% type 16). HPV predicted loco-regional control, event-free survival and overall survival in multivariable analysis. Within the surgery with adjuvant radiotherapy (n=110), definitive radiotherapy-alone (n=24) and definitive radiotherapy with chemotherapy (n=47) groups, patients with HPV-positive cancers were one-third or less as likely to have loco-regional recurrence, an event or to die of any cause as those with HPV-negative cancers after adjusting for age, gender, tumour grade, AJCC stage and primary site. The 14 patients treated with surgery alone were considered too few for multivariable analysis.

Conclusion:

HPV status predicts better outcome in oropharyngeal cancer treated with surgery plus adjuvant radiotherapy as well as with definitive radiation therapy±chemotherapy.

Schneiderian Papillomas and Carcinomas: A Retrospective Study with Special Reference to p53 and p16 tumor suppressor gene expression and association with HPV

Schneiderian papillomas are uncommon benign tumors of the sinonasal area. They are prone to local aggressiveness and recurrence, and some undergo malignant progression. We analyzed specimens obtainedfrom 67 Chinese patients who had presented to the ENT department of a regional hospital with biopsy-proven schneiderian papilloma. Seven of these patients had either synchronous or metachronous carcinoma, 1 of whom had pure carcinoma in situ. For each case, we documentedthe morphology, immunohistochemical expression of tumor suppressor genes p53 and p16, and any association with human papillomavirus (HPV) infection as detected by either polymerase chain reaction or in situ hybridization techniques. We found that severe dysplasia andp53positivity were strongly associated with malignantprogression. Association with HPV was demonstrated in 22 of the 67patients (33%); the association was strongest among patients with exophytic papillomas and carcinomas. The effect of HPV in papilloma oncogenesis probably begins duringthe early phase, while other factors are responsible for progression to carcinoma. We conclude thatp53-positive, dysplastic schneiderian papillomas warrant aggressive surgical treatment.

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.

Clinical implications of the tumor volume reduction rate in head-and-neck cancer during definitive intensity-modulated radiotherapy for organ preservation

PURPOSE

To investigate the prognostic value of the volume reduction rate (VRR) in patients with head-and-neck cancer treated with intensity-modulated radiotherapy (IMRT).

METHODS AND MATERIALS

Seventy-six patients with oropharyngeal cancer (OPC) and another 76 with hypopharyngeal cancer (HPC) were enrolled in volumetric analysis. All patients received allocated radiotherapy courses. Adaptive computed tomography was done 4 to 5 weeks after the start of IMRT. Primary tumor volume measurement was derived using separate images for the pretreatment gross tumor volume (pGTV) and the interval gross tumor volume.

RESULTS

In the OPC group, the pGTV ranged from 6.6 to 242.6 mL (mean, 49.9 mL), whereas the value of the VRR ranged from 0.014 to 0.74 (mean, 0.43). In HPC patients, the pGTV ranged from 4.1 to 152.4 mL (mean, 35.6 mL), whereas the VRR ranged from -1.15 to 0.79 (mean, 0.33). Multivariate analysis of the primary tumor relapse-free survival for OPC revealed three prognostic factors: T4 tumor (p = 0.0001, hazard ratio 7.38), pGTV ≥20 mL (p = 0.01, hazard ratio 10.61), and VRR <0.5 (p = 0.001, hazard ratio 6.49). Multivariate analysis of the primary tumor relapse-free survival for HPC showed two prognostic factors: pGTV ≥30 mL (p = 0.001, hazard ratio 2.87) and VRR <0.5 (p = 0.03, hazard ratio 2.25).

CONCLUSION

The VRR is an outcome predictor for local control in OPC and HPC patients treated with IMRT. Those with large tumor volumes or a VRR <0.5 should be considered for a salvage operation or a dose-escalation scheme.

Low prevalence of human papillomavirus in oral cavity carcinomas

BACKGROUND

Increasing evidence shows that Human Papillomavirus (HPV) is preferentially associated with some head and neck squamous cell carcinomas (HNSCCs), with variable infection rates reported.

METHODS

We assessed HPV involvement in HNSCC using the Roche Linear Array HPV Genotyping Test, which can detect 37 different HPV types. We examined the prevalence of HPV infection in 92 HNSCCs (oropharynx, oral cavity, and other HNSCC sites).

RESULTS

HPV was frequently detected in oropharyngeal cancers (OPCs) (16/22, 73%), but was uncommon in oral cavity cancers (2/53, 4%), and in other HNSCC subsites (1/17, 6%). HPV positive tumors were associated with patients that were 40-60 years old (p = 0.02), and node positive (p = < 0.0001). HPV 16 was the most prevalent type, but other types detected included 6, 18, 33, 35, 45, and 52/58.

CONCLUSION

Our results show that in contrast to oropharyngeal cancers, oral cancers and other HNSCCs infrequently harbor HPV.

p16 expression in conventional and desmoplastic trichilemmomas

The expression of p16 in cutaneous neoplasms is upregulated in melanocytic neoplasms, ultraviolet radiation-induced neoplasms, such as actinic keratoses and squamous cell carcinomas, and in lesions related to human papillomavirus, such as Bowen's disease and bowenoid papulosis. In cervical dysplasia and tonsillar carcinoma, there is such a close relationship between p16 and human papillomavirus (HPV) to the extent that p16 immunostaining is used as a surrogate marker for the presence of HPV proteins. In this study we were interested in the expression pattern of p16 in trichilemmomas. Twenty-six conventional and 19 desmoplastic trichilemmomas were immunohistochemically stained for p16. p16 immunostaining was noted in the majority of conventional (80.8%) and desmoplastic trichilemmomas (73.7%). The staining pattern was both nuclear and cytoplasmic. The staining intensity was more pronounced in the desmoplastic variant. We describe for the first time p16 expression in trichilemmomas and discuss our findings in conjunction with p16 expression found in other cutaneous neoplasms. Additionally, the relationship of p16 to HPV infection is critically evaluated.

Human papillomavirus-related diseases: oropharynx cancers and potential implications for adolescent HPV vaccination

Molecular and epidemiological data now support an etiologic role for oncogenic human papillomavirus (HPV) in oral cancers in women and men. Recent studies have demonstrated an increase in the incidence of HPV-associated oral cancers in the United States. Moreover, the incidence rates for these cancers are higher in men than women. Oral HPV infections acquired through oral sex appear to be the principal risk factor for HPV-associated oral cancers. Despite reports in the popular press that the prevalence of oral sexual behaviors is increasing in the adolescent population, trends in these behaviors over time are largely unavailable. However, data indicate that oral-genital contact is frequently practiced among adolescents; adolescents do not typically consider this a risky behavior. The majority of oral cancers (approximately 90%) caused by HPV are identified as HPV 16 positive. Therefore, HPV-associated oral cancers could be prevented by a prophylactic vaccine if the vaccine were demonstrated to be capable of preventing oral HPV 16 infection. These findings have created new potential opportunities for the primary prevention of oral cancers.