Hybrid Capture 2 human papilloma virus testing for head and neck cytology specimens

High-risk human papillomavirus testing in cytology aspiration samples from the head and neck part 1: a review of the literature on available testing options

Human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma is increasing in incidence and is often first diagnosed on a cytology fine needle aspiration (FNA) specimen of metastatic nodal disease of the neck. In the setting of oropharyngeal squamous cell carcinoma, HPV status defines the disease with HPV-associated tumors having better overall prognosis than those that are HPV negative. Furthermore, metastatic squamous cell carcinoma of the neck of unknown origin requires testing for HPV as a positive result suggests an oropharyngeal primary. As a result, HPV testing in aspirate samples is increasingly important for the proper diagnosis and treatment of patients with head and neck squamous cell carcinoma. Although HPV testing in cervicovaginal cytology specimens is common and well-established, testing in head and neck FNA samples remains challenging. p16 immunohistochemistry is an excellent surrogate marker for HPV in tumors of known or suspected oropharyngeal origin, but the criteria used in histologic specimens may not be appropriate in cytology samples. FNA samples are more frequently hypocellular, and cytology cell blocks have variable fixation and processing steps, limiting the utility of p16 immunohistochemistry. Other potential testing options have been reported in the literature including staining of aspirate smears and molecular testing of liquid-based samples. The American Society of Cytopathology Clinical Practice Committee recently surveyed the American Society of Cytopathology membership to determine the current state of HPV testing in aspirate samples, and this review article is designed to provide a summary of the current literature on various testing options in FNA samples.

Liquid phase human papillomavirus genotype analysis of aspirated metastatic head and neck squamous cell carcinoma: Fine needle aspiration supernatant is a rich source of tumor DNA that can increase the diagnostic yield

BACKGROUND

Most patients with human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSC) present with lymph node metastasis. In these patients, fine needle aspiration (FNA) is not only a diagnostic tool, but a means for determining HPV status. HPV status, in turn, is used to determine tumor origin, prognosis, and even guide therapy. Thus, the limited sampling afforded by FNA must be optimized to meet heavy clinical demands.

PURPOSE

The purpose of this study was to determine whether the residual supernatant portion of the FNA could serve as a resource for reliable determination of HPV status DESIGN/METHOD: 25 FNAs from 24 patients with metastatic HNSC underwent HPV genotyping of post-centrifuged supernatant fluid from FNA needle rinses. HPV genotyping was performed using two real time PCR-based assays, the two-step LightCycler and the one-step automated cobas HPV tests. HPV status of the supernatant was compared with the paired FNA cell blocks and/or surgical tissue samples.

RESULTS

The supernatant was adequate for HPV testing in 24 (96%) of 25 cases. Of these, 14 (56%) were HPV positive and 11 (44%) negative by the LightCycler assay. HPV16 was the most commonly detected genotype (n = 12). When results of supernatant and paired cell block testing were compared, HPV status was concordant in all cases. The LightCycler method was more sensitive than the cobas assay due to its ability to detect an expanded profile of HPV variant genotypes.

CONCLUSION

The current standard of practice for patients with HNSC who undergo FNA is to construct a cell block and then discard the supernatant. This supernatant is a rich source of tumor DNA that can be used to detect HPV status. It should not be wasted.

Determination of high-risk HPV status of head and neck squamous cell carcinoma using the Roche cobas HPV test on cytologic specimens and acellular supernatant fluid

BACKGROUND

High-risk human papillomavirus-positive (hrHPV+) oropharyngeal squamous cell carcinomas comprise a subset of head and neck squamous cell carcinomas (HNSCCs) with a distinct biology and prognosis. Commonly, the diagnosis of HNSCC is rendered on fine-needle aspiration (FNA). Because cell blocks may be insufficient for determining HPV status using microscopy-based techniques, the ability of liquid-based assays was examined in the current study.

METHODS

The performance of the Roche cobas 4800 platform was evaluated on the FNA material from the cell pellet and corresponding cell-free supernatant fluid specimens of primary and metastatic HNSCCs. These results were compared with the p16 immunostain result from the histologic material obtained from the same patient. Discrepant cases were adjudicated using hrHPV RNA in situ hybridization.

RESULTS

A total of 41 samples (23 primary tumors and 18 lymph node metastases) were acquired from 34 patients with HNSCC. Primary tumors included the oropharynx (20 samples), oral cavity (13 samples), larynx (3 samples), and skin (3 samples). In 2 cases, a primary tumor could not be identified. Twenty-three samples (56%) were found to be p16 positive by immunohistochemistry. Twenty-two samples were found to be positive on cobas hrHPV testing from both cell pellet and cell-free supernatant fluid. Two cell-free supernatant fluid specimens yielded indeterminate cobas results. At the time additional hrHPV RNA in situ hybridization analysis was performed, one cobas-positive cell pellet was deemed to be a false-positive result. The sensitivity of the cobas assay was 100% for pellet material and cell-free supernatant fluid, with specificities of 94.7% and 100%, respectively.

CONCLUSIONS

cobas hrHPV testing of HNSCC specimens demonstrated high concordance with p16 immunohistochemistry on the corresponding cell block and/or tissue specimen. Using the cell-free supernatant fluid in this platform could provide accurate HPV results while conserving material for cytomorphologic analyses.

Current Status of p16 Immunohistochemistry and HPV Testing in Fine Needle Aspiration Specimens of the Head and Neck

Human papilloma virus (HPV)-related squamous cell carcinoma (SCC) is biologically unique and has a better prognosis than conventional SCC of the head and neck. p16 immunohistochemistry emerged as a valuable surrogate marker for HPV in oropharyngeal SCC. The criteria for a positive p16 result in tissue specimens are well established. However, there is no consensus regarding interpreting p16 staining in cell blocks and other cytology specimens. This review discusses the current evidence on p16 testing in cytology specimens and also highlights other methods for HPV testing, including DNA and RNA in situ hybridization, as well as other molecular HPV tests.

Association of DFNA5, SYK, and NELL1 variants along with HPV infection in oral cancer among the prolonged tobacco-chewers

Southeast Asia, especially India, is well known for the highest use of smokeless tobacco. These products are known to induce oral squamous cell carcinoma. However, not all long-term tobacco-chewers develop oral squamous cell carcinoma. In addition, germline variants play a crucial role in susceptibility, prognosis, development, and progression of the disease. These prompted us to study the genetic susceptibility to oral squamous cell carcinoma among the long-term tobacco-chewers. Here, we presented a retrospective study on prolonged tobacco-chewers of Northeast India to identify the potential protective or risk-associated germline variants in tobacco-related oral squamous cell carcinoma along with HPV infection. Targeted re-sequencing (n = 60) of 170 genetic regions from 75 genes was carried out in Ion-PGM™ and validation (n = 116) of the observed variants was done using Sequenom iPLEX MassARRAY™ platform followed by polymerase chain reaction-based HPV genotyping and p16-immunohistochemistry study. Subsequently, estimation of population structure, different statistical and in silico approaches were undertaken. We identified one nonsense-mediated mRNA decay transcript variant in the DFNA5 region (rs2237306), associated with Benzo(a)pyrene, as a protective factor (odds ratio = 0.33; p = 0.009) and four harmful (odds ratio > 2.5; p < 0.05) intronic variants, rs182361, rs290974, and rs169724 in SYK and rs1670661 in NELL1 region, involved in genetic susceptibility to tobacco- and HPV-mediated oral oncogenesis. Among the oral squamous cell carcinoma patients, 12.6% (11/87) were HPV positive, out of which 45.5% (5/11) were HPV16-infected, 27.3% (3/11) were HPV18-infected, and 27.3% (3/11) had an infection of both subtypes. Multifactor dimensionality reduction analysis showed that the interactions among HPV and NELL1 variant rs1670661 with age and gender augmented the risk of both non-tobacco- and tobacco-related oral squamous cell carcinoma, respectively. These suggest that HPV infection may be one of the important risk factors for oral squamous cell carcinoma in this population. Finally, we newly report a DFNA5 variant probably conferring protection via nonsense-mediated mRNA decay pathway against tobacco-related oral squamous cell carcinoma. Thus, the analytical approach used here can be useful in predicting the population-specific significant variants associated with oral squamous cell carcinoma in any heterogeneous population.

Human Papillomavirus Testing in Head and Neck Carcinomas: Guideline From the College of American Pathologists

Context Human papillomavirus (HPV) is a major cause of oropharyngeal squamous cell carcinomas, and HPV (and/or surrogate marker p16) status has emerged as a prognostic marker that significantly impacts clinical management. There is no current consensus on when to test oropharyngeal squamous cell carcinomas for HPV/p16 or on which tests to choose. Objective To develop evidence-based recommendations for the testing, application, interpretation, and reporting of HPV and surrogate marker tests in head and neck carcinomas. Design The College of American Pathologists convened a panel of experts in head and neck and molecular pathology, as well as surgical, medical, and radiation oncology, to develop recommendations. A systematic review of the literature was conducted to address 6 key questions. Final recommendations were derived from strength of evidence, open comment period feedback, and expert panel consensus. Results The major recommendations include (1) testing newly diagnosed oropharyngeal squamous cell carcinoma patients for high-risk HPV, either from the primary tumor or from cervical nodal metastases, using p16 immunohistochemistry with a 70% nuclear and cytoplasmic staining cutoff, and (2) not routinely testing nonsquamous oropharyngeal carcinomas or nonoropharyngeal carcinomas for HPV. Pathologists are to report tumors as HPV positive or p16 positive. Guidelines are provided for testing cytologic samples and handling of locoregional and distant recurrence specimens. Conclusions Based on the systematic review and on expert panel consensus, high-risk HPV testing is recommended for all new oropharyngeal squamous cell carcinoma patients, but not routinely recommended for other head and neck carcinomas.

Aptima HR-HPV testing from Diff-Quick-stained fine-needle aspiration smears of oropharyngeal squamous cell carcinoma

INTRODUCTION

Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (SCC) is a biologically unique form of carcinoma that is important to identify for prognosis and treatment. The objective of this study was to evaluate the performance of the Aptima HPV assay using Diff-Quick (DQ) stained smears from fine-needle aspiration (FNA) of HPV-related oropharyngeal SCC.

MATERIALS AND METHODS

Patients with a diagnosis of head and neck SCC who also had FNA sample demonstrating metastatic disease were identified. Using a mounting media-based cell transfer technique, approximately 200 tumor cells were selected and harvested from DQ-stained aspirate smeared slides. The selected cells were tested for high risk HPV using the Aptima HPV assay, an in vitro nucleic acid amplification test for the qualitative detection of E6/E7 viral messenger RNA from high-risk types of HPV. These results were compared with the p16 immunohistochemical staining of the corresponding surgical pathology specimens.

RESULTS

Twenty-eight of 32 (87.5%) FNAs of p16-positive oropharyngeal SCC were positive for high-risk HPV by the Aptima assay and 18 of 18 (100%) FNAs of p16-negative SCC were negative for high-risk HPV by the Aptima assay.

CONCLUSIONS

DQ-stained FNA smears can be used by the Aptima HPV assay to accurately detect high-risk HPVs in oropharyngeal SCCs with a sensitivity of 87.5% and a specificity of 100%. This provides an alternative to p16 immunohistochemical staining of FNA cell block material, which may not be available on all specimens.