The role of cytology in the era of HPV-related head and neck carcinoma

A simplified molecular method to detect high-risk HPV using the Aptima HPV assay on head and neck FNA smears

BACKGROUND

Fine-needle aspiration is used as a diagnostic tool in head and neck oropharyngeal squamous cell carcinoma and its metastases. Prognosis and treatment rely on the presence or absence of the human papilloma virus. The purpose of this study was to validate the performance of the Aptima HPV assay using Hema-Diff stained fine-needle aspiration smears in the diagnosis of human papilloma virus-related oropharyngeal squamous cell carcinoma using a simplified method to obtain tumor cells for testing.

METHODS

Patients with a diagnosis of squamous cell carcinoma and positive p16 immunohistochemical staining were identified. Aptima Specimen Transport Media was used to remove tumor cells from the Hema-Diff stained slides using a moistened swab. The selected cells were tested for high risk-human papilloma virus using the Aptima HPV assay and Aptima HPV 16 18/45 genotype assay. The results were compared with the p16 immunohistochemical staining of the related cell block and surgical specimens.

RESULTS

Twenty-one of the 21 (100%) p16-positive cases were found to be positive for high risk-human papilloma virus, whereas 20 of 21 (95%) negative cases were found to be negative for high risk-human papilloma virus using the Aptima HPV assay.

CONCLUSION

The Aptima HPV assay can be used to detect high-risk human papilloma virus in Hema-Diff stained fine-needle aspiration smears of oropharyngeal squamous cell carcinoma with a sensitivity of 100% and a specificity of 95%. This provides a valuable alternative to p16 immunohistochemical staining of cell block sections that often lack appropriate numbers of tumor cells.

The utility of high-risk human papillomavirus in situ hybridization in cytology cell block material from cystic head and neck lesions

BACKGROUND

Human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV-OPSCC) presents frequently as metastasis in a neck lymph node that may be cystic or necrotic. Fine-needle aspiration (FNA) biopsies are often first-line diagnostic procedures. p16 immunohistochemistry (IHC) is a surrogate marker for high-risk HPV (hrHPV) infection but can be challenging to interpret. This study evaluated the use of hrHPV in situ hybridization (ISH) in cytology cell blocks of cystic neck lesions.

METHODS

Twenty-four FNA cases with cell blocks and surgical correlates were evaluated. p16 IHC and hrHPV ISH were assessed on cell blocks (C-p16 and C-hrHPV ISH), and hrHPV ISH on surgical samples (S-hrHPV ISH). All results were classified as negative, positive, or equivocal.

RESULTS

Two cases were excluded because of insufficient tissue on recut. On the basis of C-hrHPV ISH cases, 12 were positive, 5 were negative, and 5 were equivocal. All 12 positive C-hrHPV ISH cases had concordant S-hrHPV ISH with no false positives. Of the 5 negative C-hrHPV ISH cases, 4 had concordant S-hrHPV ISH, and 1 had a discordant S-hrHPV ISH. Of the 5 equivocal C-hrHPV ISH cases, S-hrHPV ISH were both positive and negative. Fourteen cases were equivocal by C-p16; 9 cases were reliably classified by C-hrHPV ISH (5 positive, 4 negative; 64%).

CONCLUSIONS

C-hrHPV ISH can be reliably used, especially when positive. A negative or equivocal interpretation of C-hrHPV ISH may warrant repeat testing. Compared to C-p16, C-hrHPV ISH is more frequently diagnostic and could be helpful for HPV-OSCC diagnosis and management.

Human papillomavirus testing in metastatic squamous cell carcinoma of the neck with unknown primary using PCR on fine-needle aspiration smears: a prospective clinical study

PURPOSE

Squamous cell carcinoma metastasis of the head and neck with unknown primary tumor (CUP) comprises a diagnostic challenge. Human papillomavirus (HPV) testing on cytologic specimens is gaining increasing focus as this may facilitate an early diagnosis of HPV-induced oropharyngeal carcinoma. This study aimed to prospectively assess PCR-based HPV-DNA testing on FNA smears in a clinical setting.

METHODS

Patients referred to a tertiary Head and Neck Cancer Center with suspected CUP were included from November 2016 to November 2018. Scraped cell material from FNA smears was analyzed for HPV-DNA with PCR using general primers (GP5 + /GP6 +) and correlated with the origin and histology of the primary tumor (oropharynx vs. outside oropharynx or benign tumor). The turn-around time reflecting the workflow for HPV-DNA testing by PCR was also calculated.

RESULTS

A total of 93 patients were enrolled in the study. The sensitivity and specificity were 86.7% [95% CI 75.4-94.1%] and 92.0% [95% CI 74.0-99.0%], and the positive and negative predictive values were 96.3% [95% CI 87.3-99.0%] and 74.2% [95% CI 59.9-84.7%], respectively. The turn-around time for HPV testing was a mean four calendar days.

CONCLUSION

HPV-DNA testing on FNA smears can be performed within a reasonable timeframe and can guide for the detection of an HPV-positive oropharyngeal primary tumor in the clinical setting for patients presenting with CUP of the head and neck.

Diagnostic utility of p16 immunocytochemistry in metastatic cervical lymph nodes in head and neck cancers

BACKGROUND

Human papilloma virus (HPV) testing can be useful in work-up of patients presenting with cervical node metastasis, suspected to be of head and neck origin as HPV positive tumors show better response to therapy. The current study was planned to detect HPV in aspirates from metastatic cervical nodes using p16 immunocytochemistry in head and neck squamous cell carcinoma (HNSCC). Further correlation of HPV status between node metastasis and primary tumor was done.

METHODS

The prospective study included 50 patients diagnosed as metastatic SCC in cervical nodes on fine needle aspiration with either known head and neck primary or primary detected post cytodiagnosis. Immunostaining for p16 was carried out on both smears and tissue sections.

RESULTS

Forty-three patients were male and seven were female. Age of the patients ranged from 35 to 80 years. Primary sites of HNSCC were oropharynx (25), oral cavity (14), and larynx (11). Immunocytochemistry for p16 on smears showed positivity in 28 cases. Immunohistochemistry for p16 in primary tumors was positive in 34. There was substantial agreement between p16 immunocytochemistry and immunohistochemistry (Kappa value: 0.823). The sensitivity of p16 immunocytochemistry for the detection of HPV in metastatic HNSCC was 82.4% while the specificity was 100%. The positive and negative predictive values were 100% and 72.7%, respectively.

CONCLUSIONS

P16 immunocytochemistry in HNSCC metastatic to cervical node mirrors the HPV status of the corresponding primary tumor. Hence in tumors of unknown origin presenting as cervical node metastasis, p16 immunocytochemistry can be employed for localization of the primary.

Cytological interpretation of p16 immunohistochemistry in head and neck carcinomas: does the choice of fixative matter?

INTRODUCTION

Fine-needle aspiration (FNA) of nodal metastases plays a key role in the diagnosis of oropharyngeal squamous cell carcinoma (OPSCC). Because of significant clinical implications of human papillomavirus (HPV)-related OPSCC, immunohistochemistry for p16 as a surrogate marker for high-risk HPV is an important ancillary test. After our laboratory switched from CytoLyt to formalin fixative for FNA needle rinses generating cell block (CB) material, we investigated the impact of this protocol change on the accuracy of p16 results.

MATERIALS AND METHODS

FNA specimens of head and neck lesions with p16 staining performed on CB, from 1 year before and after the implementation of formalin-fixed CB (FCB) were identified. Nuclear and cytoplasmic p16 expression was scored and compared to p16 status on corresponding surgical specimens.

RESULTS

There were no false-positive results with either fixative. CytoLyt-fixed CB (CCB) had 47% (7 of 15) false-negative cases, whereas FCB had none, with 100% diagnostic accuracy for p16-negative (n = 6) and p16-positive (n = 15) results. False-negative CCB showed 0% to 10% nuclear and 0% to 65% weak cytoplasmic staining, whereas true-positive CCB showed 10% to 85% nuclear and 35% to 90% cytoplasmic staining. p16-negative FCB showed 0% nuclear and cytoplasmic staining, and p16-positive FCB showed 30% to 100% moderate-strong nuclear and cytoplasmic staining. Interobserver variability was greater with CCB.

CONCLUSIONS

In our laboratory, formalin fixation of CB material improved the accuracy of p16 interpretation. Staining in FCB was also more robust than CCB, which showed weaker cytoplasmic and more focal nuclear staining. Therefore, we advocate formalin fixation for head and neck cytology specimens that may require p16 testing.

Multiplex HPV RNA in situ hybridization/p16 immunohistochemistry: a novel approach to detect papillomavirus in HPV-related cancers. A novel multiplex ISH/IHC assay to detect HPV

BACKGROUND

High-risk human papillomavirus (HR-HPV) is notoriously associated with tumor progression in a broad spectrum of malignancies. Detection of HR-HPV is clinically important in the management of HPV-related carcinomas, particularly in cervical cancer and oropharyngeal squamous cell carcinoma (OPSCC). Several methods for HPV detection are currently available including Polymerase chain reaction (PCR)-based techniques, DNA in situ hybridization (ISH), RNA ISH, and p16 immunohistochemistry (IHC). Currently, the guidelines for HPV detection in cervical carcinoma are available, while no clear consensus has not yet been reached on the gold standard for HPV testing in OPSCC. Multimodality testing could help to reliably identify patients with transcriptionally active high-risk HPV-positive.

METHODS

We propose a multiplex approach carrying out HPV RNA ISH and p16 IHC on the same slide to detect simultaneously HPV E6/E7 transcripts and p16INK4a overexpression. We tested this assay in two different series one of the cervical cancers with p16-positive, as control, and the other of oropharyngeal squamous cell carcinomas with blind p16 status.

RESULTS

The multiplex HPV RNA ISH /p16 IHC results in the series both of the cervical cancers and the oral-oropharyngeal cancers were fully concordant with the previous results achieved through the classic p16 IHC and HPV RNA scope carried out on two different slides.

CONCLUSIONS

Our results suggesting several advantages of this technical approach, namely an easy interpretation fully in the light field, the feasibility in formalin-fixed paraffin-embedded tissue sections, complete automation and a potential wide spreadable for routine testing in several clinical laboratories.

Threshold for interpretation of p16 immunostaining in fine-needle aspirate specimens of metastatic oropharyngeal squamous cell carcinoma

INTRODUCTION

Human papilloma virus (HPV)-associated oropharyngeal squamous cell carcinoma (HPV-OPSCC) has been recognized to have an excellent response to treatment and has a distinct pathologic staging. For this reason, HPV testing is recommended in cytology specimens of metastatic OPSCC, although the guidelines for testing are not clearly defined. The aim of the current study was to establish a threshold for interpretation of p16 in aspirates from metastatic OPSCC.

MATERIALS AND METHODS

Cases diagnosed as metastatic SCC by cytology in neck lymph nodes with concurrent p16 on cytology and on paired surgical specimen or an in situ hybridization (ISH) for HPV were included in the study. Stain intensity and percentage positive cells for p16 was compared with p16 on paired surgical pathology specimens and/or ISH RNA for HPV on cytology specimens.

RESULTS

Of the 52 cases diagnosed as metastatic SCC on neck aspirates, paired surgical pathology specimens and/or ISH HPV was available in 17 cases. A p16 expression in ≥10%-15% cells resulted in a sensitivity and negative predictive value of 66% and 37%, respectively. However, when even minimal expression in tumor fragments is considered positive, the negative predictive value increases to 100%.

CONCLUSIONS

We recommend that even minimal nuclear expression for p16 in viable tumor fragments must be considered as positive in cytology specimens. Expression limited to only background single tumor cells or in a necrotic specimen must be interpreted with caution.

Cytologic evaluation of p16 staining in head and neck squamous cell carcinoma in CytoLyt versus formalin-fixed material

BACKGROUND

The management of high-risk human papillomavirus (HR-HPV)-related oropharyngeal head and neck squamous cell carcinomas (HNSCCs) are distinct from HNSCC linked to smoking and alcohol use. HR-HPV-positive HNSCC frequently presents as a cervical lymph node metastasis. Because fine-needle aspiration (FNA) is often the initial diagnostic procedure, evaluating HR-HPV status in cytology specimens is important. The overexpression of p16 is a surrogate for HR-HPV; however, the evaluation of p16 in FNAs remains controversial.

METHODS

From September 2015 to December 2016, cytopathologists performed 25 FNAs of neck lymph nodes that were suspicious for HR-HPV-positive HNSCC. Initial passes produced smears for on-site evaluation and CytoLyt material. Additional passes were formalin-fixed. A CytoLyt cell block (CCB) and a formalin-fixed cell block (FFCB) were prepared, and p16 immunocytochemistry was performed.

RESULTS

In 24 of 25 cases, the FFCB had diffuse (≥70% of cells), strong nuclear/cytoplasmic p16 staining. In all 24 of these cases, HR-HPV was detected by in situ hybridization. The corresponding CCB had weak-to-moderate p16 staining in <70% of cells (range, 5%-60% of cells) in 17 cases, 4 had weak-to-moderate diffuse staining, and 4 were acellular. The percentage of p16-positive cells was significantly higher with FFCB than with CCB (formalin: 94% ± 2%; CytoLyt, 38% ± 7%; 2-tailed, paired Student t test; P < .001; Fisher exact test, P < .001).

CONCLUSIONS

The fixative used had a drastic impact on p16 staining, which explained the staining variability reported in the literature. FFCBs show a diffuse staining pattern, which correlates with HR-HPV status, whereas CCBs show a weaker and inconsistent staining pattern, which is more difficult to interpret.

Oral manifestations of human papillomavirus infections

Papillomaviruses are one of the oldest viruses known, dating back 330 million years. During this long evolution, human papillomaviruses (HPV) have developed into hijackers of human cellular and immune systems in which they replicate and remain silent. Systematic studies on oral HPV infections and their outcomes are still scarce. Oral HPV infections have been linked to sexual behaviour, but recent evidence supports their horizontal, mouth‐to‐mouth, transmission. Most HPV infections in infants are acquired vertically from the mother during the intrauterine period, during delivery, or later via saliva. The best‐known benign clinical manifestations of HPV infection are oral papilloma/condyloma and focal epithelial hyperplasia. Evidence is emerging which suggests that some oral HPV infections might persist. Persistent HPV infection is mandatory for HPV‐associated malignant transformation. However, progression of HPV‐induced lesions to malignancy requires additional cofactors. In the early 1980s, we provided the first evidence that a subset of oral cancers and other head and neck cancers might be causally linked to HPV infection. This review summarizes current knowledge on the virus itself, its transmission modes, as well as the full spectrum of oral HPV infections – from asymptomatic infections to benign, potentially malignant oral lesions, and squamous cell carcinoma.

Current status of clinical testing for human papillomavirus in oropharyngeal squamous cell carcinoma

While a variety of human papillomavirus (HPV) tests and surrogate markers are available, currently there is no consensus on the best detection method(s) that should be used to identify HPV-related oropharyngeal squamous cell carcinomas and serve as a standard test (or tests) for routine diagnostic use. As we begin to consider using the results of HPV testing for clinical purposes beyond simple prognostication, such as making decisions on treatment dose or duration or for targeted therapies that may be highly dependent on viral-mediated pathways, we need to be more rigorous in assessing and ensuring the performance of the test (or tests) used. Here we provide an overview of the platforms and technologies, including the strengths and limitations of each test, and discuss what steps are needed to generate confidence in their performance for use in clinical practice.

HPV-related Oropharyngeal Carcinoma: A Review of Clinical and Pathologic Features With Emphasis on Updates in Clinical and Pathologic Staging

There has been a sharp increase in the incidence of the human papilloma virus-related oropharyngeal squamous cell carcinoma, partly due to the increasingly widespread awareness and recognition of this entity. This review assimilates the recent histopathologic classifications, staging systems, rapidly expanding research base and developments in management of human papilloma virus-related oropharyngeal squamous cell carcinoma and summarizes their implications for routine diagnostic practice. Differential diagnoses and their cytologic appearances are detailed and the utility of p16 staining and other immunohistochemistry testing is discussed.

The incidence of malignancy in clinically benign cystic lesions of the lateral neck: our experience and proposed diagnostic algorithm

AIM

Solitary cystic masses of the lateral neck in an adult patient can pose a diagnostic dilemma. Malignancy must be ruled out since metastases arising from H&N cancers may mimic the presentation of benign cystic masses. Only a small number of studies have investigated the diagnostic management and malignancy rate of clinically benign solitary cervical cystic lesions. There are no established guidelines for the diagnostic evaluation.

METHODS

Retrospective review of the clinical, cytological, radiological, and pathological records of all adult patients (> 18 years) operated on for second branchial cleft cysts (BrCC) between 1/2008-2010/2016. Patients with apparent primary H&N malignancy, history of H&N cancer or irradiation, preoperative fine needle aspiration (FNA) of highly suggestive or confirmed malignancy, missing pertinent data, or age less than 18 years were excluded from analysis.

RESULTS

28 patients were diagnosed as having BrCC. The diagnosis was based on clinical findings, FNA cytology, and typical sonographic features. The histologic analysis determined an overall rate of malignancy of 10.7% (3/28): two patients had metastatic papillary thyroid carcinoma, and one patient had metastatic tonsillar squamous cell carcinoma. Purely cystic features on pre-operative ultrasound was the only significant predictor for true BrCC on final histology (p = .02).

CONCLUSIONS

Occult malignancy is not rare among adult patients presenting with a solitary cystic mass of the lateral neck. A diagnostic algorithm is proposed. Further studies are needed to establish the appropriate workup and management of an adult patient presenting with a solitary cystic mass of the lateral neck.

Validation study of HPV DNA detection from stained FNA smears by polymerase chain reaction: Improving the diagnostic workup of patients with a tumor on the neck

BACKGROUND

Human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OPSCC) often presents with cystic cervical metastasis and a small primary tumor localized in the palatine tonsils or base of the tongue, which is diagnostically challenging. Testing for HPV DNA in fine-needle aspiration (FNA) smears from metastases may facilitate a targeted diagnostic workup for identifying the primary tumor. This study was designed to assess the ability to detect HPV DNA in FNA smears with polymerase chain reaction (PCR).

METHODS

May-Grünvald-Giemsa (MGG)-stained FNA smears from metastases and corresponding surgical specimens were collected from 71 patients with known HPV-positive OPSCC, 12 patients with oral squamous cell carcinoma (OSCC), 20 patients with branchial cleft cysts, and 20 patients with Warthin tumors. Thirty-eight patients with OPSCC and 7 patients with OSCC had FNA smears available from metastases and also surgical specimens from the primary tumor and the metastases. The scraped cell material from FNA smears and corresponding surgical specimens were analyzed for HPV DNA by PCR. p16 immunohistochemistry was performed on surgical specimens from the carcinomas.

RESULTS

HPV DNA was detected in 68 of the 71 FNA smears from OPSCC metastases. All corresponding surgical specimens from primary tumors (n = 71) and metastases (n = 38) were p16- and HPV DNA-positive. All the surgical specimens and corresponding FNA smears from OSCCs, Warthin tumors, and branchial cleft cysts were HPV DNA-negative. The sensitivity and specificity were 94.7% and 100%, respectively.

CONCLUSIONS

The detection of HPV DNA in MGG-stained FNA smears by PCR is a valid method that could be implemented in routine clinical practice. Cancer Cytopathol 2016;124:820-7. © 2016 American Cancer Society.

Role of fine needle aspiration biopsy cytology in the diagnosis of infections

The role of fine needle aspiration biopsy (FNAB) cytology in diagnosing infections has expanded due to the increase in the number of immune compromised patients and the increasing role of FNAB in the developing world where infection is a major cause of illness. FNAB has become the first procedural test in cases where the clinical and imaging findings suggest an infectious lesion or where there is a differential diagnosis of infection or metastatic or primary tumor. This applies to FNAB of palpable or image directed or deep seated lesions accessed by EUS and EBUS. This article details a recommended approach and technique for FNAB of infectious lesions, and discusses the role of rapid on site evaluation and the application of ancillary testing including the rapidly expanding array of molecular tests based on FNAB material. The utility of recognizing suppurative and granulomatous infectious patterns in FNAB direct smears, and the specific cytomorphological features on routine Papanicolaou and Giemsa stains and on special stains of FNAB smears is described for a large number of bacterial, fungal, viral, parasitic, and protozoan infections. The role of cytopathologists is to now train cytopathologists in sufficient numbers to provide FNAB services, teach trainee cytopathologists and cytotechnologists, and to encourage our clinical colleagues to use FNAB in the diagnosis of infections and other lesions to the benefit of patients and the medical system. Diagn. Cytopathol. 2016;44:1024-1038. © 2016 Wiley Periodicals, Inc.

Fine-needle aspiration of cervical lymph nodes yields adequate materials for accurate HPV testing in metastatic head and neck squamous cell carcinomas

BACKGROUND

High-risk Human papillomavirus (HR-HPV)-associated head and neck squamous cell carcinoma (HNSCC) is a distinct epidemiologic and pathologic disease. The data of HR-HPV testing on fine-needle aspiration (FNA) materials of cervical lymph nodes in patients with metastatic HNSCC are limited.

METHODS

We retrospectively reviewed metastatic HNSCC cases with cervical lymph node FNAs which were tested for p16 immunohistochemistry (IHC) and HR-HPV DNA in situ hybridization (ISH).

RESULTS

Of the 87 cases studied, the overall adequacy rate of cell block material was 86% for HR-HPV ISH, 93% for p16 IHC, 84% for both and 95% for either one. Pathologist-performed FNAs showed significantly higher percentage of satisfactory specimens for p16 and HR-HPV tests than clinician-performed FNAs. Of the 73 cases adequate for both p16 IHC and HR-HPV ISH, the concordant rate between p16 and HR-HPV results was 78%. P16 positivity had sensitivity of 90% and specificity of 75% to predict primary oropharyngeal HNSCC, while HR-HPV test showed a similar high sensitivity (91%) but a better specificity (94%).

CONCLUSION

FNAs of cervical lymph nodes yield adequate materials for reliable HR-HPV testing in metastatic HNSCCs and should be incorporated into routine pathologic evaluation for these patients. The high concordance between p16 IHC and HR-HPV ISH suggests p16 IHC may serve as a surrogate for HR-HPV ISH in metastatic HNSCC cases with oropharyngeal origin and is helpful to pinpoint primary tumor site. Diagn. Cytopathol. 2016;44:792-798. © 2016 Wiley Periodicals, Inc.

The utility of p16 immunostaining in fine needle aspiration in p16-positive head and neck squamous cell carcinoma

Many patients with human papillomavirus (HPV)-related head and neck squamous cell carcinoma present initially with cervical nodal metastasis. Fine needle aspiration (FNA) of the nodal disease might be the only diagnostic material available for p16 immunohistochemistry (IHC) and HPV testing. The current study aims to evaluate p16 IHC in FNA and establish guidelines for its interpretation. The percentage and intensity of p16 IHC staining were examined in 60 matched FNA and surgical cases. Cytomorphologic features were included in the analysis. p16 IHC staining was correlated with the results seen in the surgical specimens and with HPV in situ hybridization (ISH). Analysis of different thresholds demonstrated that the threshold of 10% p16 tumor cell positivity had the best overall concordance rate with surgical p16 IHC (κ = 0.650) and with FNA HPV-ISH (κ = 0.714). Applying the recommended p16 positivity threshold for surgical specimens (70%) on FNA materials resulted in low sensitivity (39%) and low negative predictive value (26%). In comparison with p16 IHC in surgical specimens, 6/46 FNA cases (13%) were falsely negative for p16. All 6 cases were associated with necrotic background, two (33%) lacked large tumor clusters, and one (17%) had low cellularity. The recommended threshold for p16 IHC on surgical specimens should not be used in cytology materials. The cutoff value for p16 immunostain in FNA specimens showing best results in our series is 10%. When p16 IHC is negative in FNA specimens, a repeat stain on a surgical specimen is recommended to avoid a false-negative diagnosis.