Accuracy of high-risk HPV DNA PCR, p16(INK4a) immunohistochemistry or the combination of both to diagnose HPV-driven oropharyngeal cancer.

BACKGROUND: The incidence of high-risk human papillomavirus (hrHPV)-driven head and neck squamous cell carcinoma, in particular oropharyngeal cancers (OPC), is increasing in high-resource countries. Patients with HPV-induced cancer respond better to treatment and consequently have lower case-fatality rates than patients with HPV-unrelated OPC. These considerations highlight the importance of reliable and accurate markers to diagnose truly HPV-induced OPC. METHODS: The accuracy of three possible test strategies, i.e. (a) hrHPV DNA PCR (DNA), (b) p16(INK4a) immunohistochemistry (IHC) (p16), and (c) the combination of both tests (considering joint DNA and p16 positivity as positivity criterion), was analysed in tissue samples from 99 Belgian OPC patients enrolled in the HPV-AHEAD study. Presence of HPV E6*I mRNA (mRNA) was considered as the reference, indicating HPV etiology. RESULTS: Ninety-nine OPC patients were included, for which the positivity rates were 36.4%, 34.0% and 28.9% for DNA, p16 and mRNA, respectively. Ninety-five OPC patients had valid test results for all three tests (DNA, p16 and mRNA). Using mRNA status as the reference, DNA testing showed 100% (28/28) sensitivity, and 92.5% (62/67) specificity for the detection of HPV-driven cancer. p16 was 96.4% (27/28) sensitive and equally specific (92.5%; 62/67). The sensitivity and specificity of combined p16 + DNA testing was 96.4% (27/28) and 97.0% (65/67), respectively. In this series, p16 alone and combined p16 + DNA missed 1 in 28 HPV driven cancers, but p16 alone misclassified 5 in 67 non-HPV driven as positive, whereas combined testing would misclassify only 2 in 67. CONCLUSIONS: Single hrHPV DNA PCR and p16(INK4a) IHC are highly sensitive but less specific than using combined testing to diagnose HPV-driven OPC patients. Disease prognostication can be encouraged based on this combined test result.

HPV DNA genotyping, HPV E6*I mRNA detection, and p16INK4a/Ki-67 staining in Belgian head and neck cancer patient specimens, collected within the HPV-AHEAD study.

BACKGROUND: The main risk factors for head and neck cancer (HNC) are tobacco and alcohol use. However, an important fraction of oropharyngeal cancer (OPC) is caused by human papillomaviruses (HPV), a subgroup with increasing incidence in several western countries. METHODS: As part of the HPV-AHEAD study, we assessed the role of HPV infection in 772 archived tissue specimens of Belgian HNC patients: 455 laryngeal (LC), 106 oral cavity (OCC), 99 OPC, 76 hypopharyngeal (HC), and 36 unspecified parts of the head and neck. All specimens were tested for HPV DNA (21 genotypes); whereof all HPV DNA-positives, all HPV DNA-negative OPCs and a random subset of HPV DNA-negatives of the other HNC-sites were tested for the presence of type-specific HPV RNA and p16INK4a over-expression. RESULTS: The highest HPV DNA prevalence was observed in OPC (36.4 %), and was significantly lower (p < 0.001) in the other HNCs (OCC:7.5 %, LC:6.6 %). HPV16 was the most common HPV-genotype in all HNCs. Approximately 83.0 % of the HPV DNA-positive OPCs tested HPV RNA or p16-positive, compared to about 37.5 % and 44.0 % in OCC and LC, respectively. Estimation of the attributable fraction of an HPV infection in HNC was very similar for HPV RNA or p16 in addition to DNA-positivity; with 30 % for OPC, and 3 % for OCC and LC. CONCLUSION: Our study confirms the heterogeneity of HPV DNA prevalence across anatomical sites in HNC, with a predominance of HPV16 in all sites. The estimated proportion of HPV-driven HNC in Belgium, during the period 1980-2014, was 10 times higher in OPC compared to OCC and LC.

The IMproving Primary Screening And Colposcopy Triage trial: human papillomavirus, cervical cytology, and histopathologic results from the baseline and 1-year follow-up phase.

BACKGROUND: An increase in human papillomavirus test volumes is expected in the near future because human papillomavirus-based screening protocols are expected to become more widely adopted. OBJECTIVE: The IMproving Primary Screening And Colposcopy Triage trial, a prospective, multicenter, US-based cervical cancer screening trial, was conducted to obtain US Food and Drug Administration approvals for the new, high-throughput cobas human papillomavirus (cobas HPV) test for use on the cobas 6800/8800 Systems (cobas HPV) for detecting cervical precancerous and cancerous cells (cervical intraepithelial neoplasia of grade 2 or worse and grade 3 or worse). Here, the baseline demographics, human papillomavirus test results, cervical cytology, and histopathologic results are presented. In addition, the baseline and 1-year risks of cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse associated with the human papillomavirus results are reported. STUDY DESIGN: In total, 35,263 women aged between 25 and 65 years undergoing routine screening were enrolled; liquid-based cytology and 2 polymerase chain reaction-based tests for high-risk human papillomavirus were performed. Women with abnormal Papanicolaou cytology, women positive for high-risk human papillomavirus by either of the 2 human papillomavirus tests, and a random subset of women negative according to the Papanicolaou cytology and the 2 human papillomavirus tests were referred for a colposcopy and cervical biopsy. Women who did not meet the study endpoint were eligible for the 1-year follow-up study phase. Verification bias-adjusted cervical disease prevalence and risks and 95% confidence intervals were computed. RESULTS: The prevalence of atypical squamous cells of undetermined significance and worse than atypical squamous cells of undetermined significance cytology were 6.5% and 3.2%, respectively. Prevalence of high-risk human papillomavirus, human papillomavirus 16, and human papillomavirus 18 based on the new cobas HPV test were 15.1%, 3.1%, and 1.4%, respectively. Both cytologic abnormalities and human papillomavirus positivity declined with increasing age. Among women who had a colposcopy and biopsy, the prevalence of cervical intraepithelial neoplasia grade 2 or worse and grade 3 or worse were 8.8% and 3.6%, respectively. The baseline and 1-year cumulative risks for cervical intraepithelial neoplasia grade 3 or worse were 13.6% and 16.9%, respectively, among women who tested positive for human papillomavirus 16. Women who tested negative for human papillomavirus had the lowest 1-year cumulative risk for cervical intraepithelial neoplasia grade 3 or worse (0.06%). CONCLUSION: The contemporary, age-specific prevalence of human papillomaviruses (including human papillomavirus 16 and 18), cytologic abnormalities, and cervical intraepithelial neoplasia in a large, US-based cervical cancer screening population provides benchmarks for healthcare policies, screening programs, and for laboratories and clinicians.

Role of mucosal high-risk human papillomavirus types in head and neck cancers in Romania.

BACKGROUND: Limited information is available about the involvement of human papillomavirus (HPV) in head and neck squamous cell carcinomas (HNSCCs) in Romanian patients. OBJECTIVE: To evaluate the HPV-attributable fraction in HNSCCs collected in Northeastern Romania. MATERIALS AND METHODS: In total, 189 formalin-fixed paraffin-embedded tissue samples (99 oral cavity tumors, 28 oropharynx, 48 pharynx, and 14 larynx/hypopharynx) were analyzed for HPV DNA and RNA using Luminex-based assays, and for overexpression of p16INK4a (p16) by immunohistochemistry. RESULTS: Of the 189 cases, 23 (12.2%) were HPV DNA-positive, comprising half of the oropharyngeal cases (14/28, 50.0%) and 9/161 (5.6%) of the non-oropharyngeal cases. HPV16 was the most prevalent HPV type (20/23, 86.9%), followed by HPV18 (5/23, 21.7%) and HPV39 (1/23, 4.3%). Only two (2/189, 1.1%) HNSCC cases were HPV-driven, i.e. positive for both HPV DNA and RNA. CONCLUSION: A very small subset of HNSCC cases within this cohort from Northeastern Romania appeared to be HPV-driven.

Role of mucosal high-risk human papillomavirus types in head and neck cancers in central India.

Mucosal high-risk (HR) human papillomaviruses (HPV) cause a subset of head and neck cancers (HNC). The HPV-attributable fraction of HNC varies substantially between countries. Although HNC has a very high incidence in the Indian subcontinent, information on the contribution of HPV infection is limited. Here, we evaluated the HPV-attributable fraction in HNC (N = 364) collected in a central region of India. HNC from three different anatomical subsites were included, namely, oral cavity (n = 252), oropharynx (n = 53) and hypopharynx/larynx (n = 59). In this retrospective study, HPV-driven HNC were defined by presence of both viral DNA and RNA. Overexpression of p16INK4a was also evaluated. HR-HPV DNA was detected in 13.7% of the cases; however, only 2.7% were positive for both HPV DNA and RNA. The highest percentage of HPV DNA/RNA double positivity was found in oropharynx (9.4%), followed by larynx (1.7%) and oral cavity (1.6%) (p = 0.02). More than half of HPV DNA/RNA-positive cases were p16INK4a -negative, while a considerable number of HPV RNA-negative cases were p16INK4a -positive (17.9%). HPV16 was the major type associated with HNC (60.0%), although cases positive for HPV18, 35 and 56 were also detected. Our data indicate that the proportion and types of mucosal HR-HPV associated with HNC in this central Indian region differ from those in other (developed) parts of the world. This may be explained by differences in smoking and/or sexual behaviour compared with North America and northern Europe. Moreover, we show that p16INK4a staining appeared not to be a good surrogate marker of HPV transformation in the Indian HNC cases.

Triaging HPV-positive women with p16/Ki-67 dual-stained cytology: Results from a sub-study nested into the ATHENA trial.

OBJECTIVES: In addition to genotyping for HPV16/18, dual-immunostaining for p16/Ki-67 has shown promise as a triage of HPV-positive women. We assessed the performance of p16/Ki-67 dual-stained cytology for triaging HPV-positive women undergoing primary HPV screening. METHODS: All women ≥25years with valid cervical biopsy and cobas® HPV Test results from the cross-sectional phase of ATHENA who were referred to colposcopy (n=7727) were eligible for enrolment. p16/Ki-67 dual-stained cytology was retrospectively performed on residual cytologic material collected into a second liquid-based cytology vial during the ATHENA enrolment visit. The diagnostic performance of dual-stained cytology, with or without HPV16/18 genotyping, for the detection of biopsy-confirmed cervical intraepithelial neoplasia grade 3 or worse (CIN3+) was determined and compared to Pap cytology. Furthermore, the number of colposcopies required per CIN3+ detected was determined. RESULTS: Dual-stained cytology was significantly more sensitive than Pap cytology (74.9% vs. 51.9%; p<0.0001) for triaging HPV-positive women, whereas specificity was comparable (74.1% vs. 75.0%; p=0.3198). Referral of all HPV16/18 positive women combined with dual-stained cytology triage of women positive for 12 "other" HPV genotypes provided the highest sensitivity for CIN3+ (86.8%; 95% CI: 81.9-90.8). A similar strategy but using Pap cytology for the triage of women positive for 12 "other" HPV genotypes was less sensitive (78.2%; 95% CI: 72.5-83.2; p=0.0003), but required a similar number of colposcopies per CIN3+ detected. CONCLUSIONS: p16/Ki-67 dual-stained cytology, either alone or combined with HPV16/18 genotyping, represents a promising approach as a sensitive and efficient triage for colposcopy of HPV-positive women when primary HPV screening is utilized.

Prospective evaluation of p16/Ki-67 dual-stained cytology for managing women with abnormal Papanicolaou cytology: PALMS study results.

BACKGROUND: Testing for the presence of the human papillomavirus (HPV) is widely accepted for triaging Papanicolaou cytology results categorized as atypical squamous cells of undetermined significance (ASC-US). In contrast, HPV testing has limited use in triaging cytological low-grade squamous intraepithelial lesions (LSILs) due to prevalence rates of typically >80%. In the current study, the authors assessed the diagnostic performance of p16/Ki-67 dual-stained cytology in triaging ASC-US and LSIL cases within the prospective, multicentric Primary ASC-US LSIL Marker Study (PALMS). METHODS: A total of 575 ASC-US cases and 529 LSIL cases from a cohort of 27,349 women who were prospectively enrolled into the PALMS study in 5 European countries were tested with p16/Ki-67 dual-stained cytology and Hybrid Capture 2 (HC2) HPV testing. Colposcopy-guided biopsy results of cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) were used as clinical endpoints. RESULTS: p16/Ki-67 dual-stained cytology demonstrated comparable (ASC-US: 94.4% for dual-stained cytology vs 100% for HC2 testing; P = .317) or lower (LSIL: 85.7% for dual-stained cytology vs 98.4% for HC2 testing; P = .005) sensitivity for CIN2+, but higher levels of specificity compared with HC2 HPV testing in both ASC-US (78.7% vs 60.4%; P<.001) and LSIL (53.3% vs 15.6%; P<.001) cases. Positive predictive values for CIN2+ were substantially higher for dual-stained cytology versus HC2 HPV testing, especially in LSIL, and in ASC-US cases for women aged <30 years. CONCLUSIONS: The clinical usefulness and efficiency of triaging women with ASC-US or LSIL Papanicolaou cytology results by p16/Ki-67 dual-stained cytology testing has been confirmed in this prospective, pan-European study. The high positive predictive value of dual-stained cytology for the presence of high-grade CIN may help to reduce the number of unnecessary colposcopy referrals.

Screening for cervical cancer precursors with p16/Ki-67 dual-stained cytology: results of the PALMS study.

BACKGROUND: Pap cytology is known to be more specific but less sensitive than testing for human papillomavirus (HPV) for the detection of high-grade cervical intraepithelial neoplasia (CIN2+). We assessed whether p16/Ki-67 dual-stained cytology, a biomarker combination indicative of transforming HPV infections, can provide high sensitivity for CIN2+ in screening while maintaining high specificity. Results were compared with Pap cytology and HPV testing. METHODS: A total of 27,349 women 18 years or older attending routine cervical cancer screening were prospectively enrolled in five European countries. Pap cytology, p16/Ki-67 immunostaining, and HPV testing were performed on all women. Positive test results triggered colposcopy referral, except for women younger than 30 years with only positive HPV test results. Presence of CIN2+ on adjudicated histology was used as the reference standard. Two-sided bias-corrected McNemar P values were determined. RESULTS: The p16/Ki-67 dual-stained cytology positivity rates were comparable with the prevalence of abnormal Pap cytology results and less than 50% of the positivity rates observed for HPV testing. In women of all ages, dual-stained cytology was more sensitive than Pap cytology (86.7% vs 68.5%; P < .001) for detecting CIN2+, with comparable specificity (95.2% vs 95.4%; P = .15). The relative performance of the tests was similar in both groups of women: younger than age 30 and 30 years or older. HPV testing in women 30 years or older was more sensitive than dual-stained cytology (93.3% vs 84.7%; P = .03) but less specific (93.0% vs 96.2%; P < .001). CONCLUSIONS: The p16/Ki-67 dual-stained cytology combines superior sensitivity and noninferior specificity over Pap cytology for detecting CIN2+. It suggests a potential role of dual-stained cytology in screening, especially in younger women where HPV testing has its limitations.