HPV-related squamous cell carcinoma of the head and neck: An update on testing in routine pathology practice.

Oropharyngeal squamous cell carcinoma caused by high-risk types of human papillomavirus (HPV) is now a well-recognized tumor entity whose incidence is on the rise. Most HPV-related oropharyngeal squamous cell carcinomas have a distinct histomorphology, and most patients fit a typical clinical profile. Importantly, HPV-related oropharyngeal carcinoma patients overall have significantly improved outcomes when compared to their HPV-negative counterparts, and the differences in tumor biology may soon lead to modifications in how they are treated. While high-risk HPV can be detected in a significant minority of head and neck squamous cell carcinomas across anatomic subsites in the head and neck, it has become clear in recent years that the biologically and clinically favorable features are limited to tumors that harbor transcriptionally active, high-risk HPV, something that occurs predominantly (but certainly not exclusively) in the oropharynx. It is now acknowledged that detecting transcriptionally active, high-risk HPV is a necessity in routine clinical practice, but there is considerable confusion among pathologists and clinicians alike about the subsites and settings in which HPV testing should be performed. Compounding this lack of clarity is the fact that there are multiple HPV testing options available, but currently there is no clear consensus on which test or combination of tests is optimal for routine diagnostic use. This review serves as an update for practicing pathologists on the current status of HPV (and surrogate marker) testing in head and neck cancers.

Bishop JA ，Lewis JS Jr ，Rocco JW ，Faquin WC ... -  《SEMINARS IN DIAGNOSTIC PATHOLOGY》

Detection of transcriptionally active high-risk HPV in patients with head and neck squamous cell carcinoma as visualized by a novel E6/E7 mRNA in situ hybridization method.

Bishop JA ，Ma XJ ，Wang H ，Luo Y ，Illei PB ，Begum S ，Taube JM ，Koch WM ，Westra WH ... -  《-》

Nonuniform Distribution of High-risk Human Papillomavirus in Squamous Cell Carcinomas of the Oropharynx: Rethinking the Anatomic Boundaries of Oral and Oropharyngeal Carcinoma From an Oncologic HPV Perspective.

Gelwan E ，Malm IJ ，Khararjian A ，Fakhry C ，Bishop JA ，Westra WH ... -  《-》

Molecular subclassification determined by human papillomavirus and epidermal growth factor receptor status is associated with the prognosis of oropharyngeal squamous cell carcinoma.

Human papillomavirus (HPV) infection is an indicator of good response to chemoradiotherapy in oropharyngeal squamous cell carcinoma (OPSCC), and epidermal growth factor receptor (EGFR) is a molecular-therapeutic target in head and neck squamous cell carcinoma. Here we investigated the prevalence and prognostic significance of HPV infection and EGFR alteration in OPSCC. We analyzed the presence of high-risk HPV using in situ hybridization, protein expressions of p16 and EGFR using immunohistochemistry, and the EGFR gene copy number gain using chromogenic in situ hybridization (CISH) in 105 cases of OPSCC. The biopsy specimens before chemoradiotherapy were used for these analyses. HPV infection and p16 protein overexpression were detected in 53.3% and 52.4% of the OPSCCs, and each factor was associated with better overall survival (P = .0026 and P = .0026) and nonkeratinizing histology (P = .0002 and P = .0004), respectively. EGFR gene copy number gain (high polysomy or amplification) was detected in 12.4% of the OPSCCs and was correlated with EGFR protein overexpression (P = .0667) and worse overall survival (P < .0001). HPV infection and EGFR gene copy number gain (EGFR CISH positive) were mutually exclusive. The HPV-negative/EGFR CISH-positive OPSCCs had significantly worse overall survival than did the HPV-positive/EGFR CISH-negative OPSCCs and HPV-negative/EGFR CISH-negative OPSCCs (P < .0001 and P < .0001, respectively). The EGFR CISH-negative OPSCCs had favorable prognosis irrespective of HPV infection. Our results suggest that EGFR gene copy number gain-positive tumors represent an HPV-negative, aggressive subgroup of OPSCCs. The molecular subclassification of OPSCCs based on HPV infection and EGFR status may serve as important information for appropriate therapeutic strategy.

Nakano T ，Yamamoto H ，Nakashima T ，Nishijima T ，Satoh M ，Hatanaka Y ，Shiratsuchi H ，Yasumatsu R ，Toh S ，Komune S ，Oda Y ... -  《-》

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.

Xu B ，Ghossein R ，Lane J ，Lin O ，Katabi N ... -  《-》