Human papillomavirus (HPV)-related oropharyngeal nonkeratinizing squamous cell carcinoma: characterization of a distinct phenotype.

We have recently shown that HPV-positive tonsillar carcinoma in young patients exhibits nonkeratinizing basaloid morphology and a characteristic immunophenotype. The purpose of this study was to review a large number of cases of oropharyngeal carcinomas, in all age groups, and to identify tumors with nonkeratinizing morphology. Using polymerase chain reaction (PCR) the prevalence and type of HPV DNA was determined in representative cases and in a control group of conventional keratinizing squamous cell carcinomas. The tumors were further characterized with a panel of immunohistochemical stains. A total of 235 carcinomas were reviewed; 141 of the tonsils and 94 in the base of tongue. Ninety (36%) of the tonsillar and 30 (32%) of the base of tongue carcinomas were nonkeratinizing (NKCa) with basal cell features; the rest were classical keratinizing squamous cell carcinomas (KSCC). HPV DNA, particularly type 16, was identified in 10 (100%) of 10 of NKCA and in only 2 (20%) of 10 of KSCC (P = .0014). NKCas were strongly reactive to p16 antibodies while KSCC showed weak and focal reactivity. Higher Ki67 and lower p53 staining scores were observed in NKCa as compared to KSCC. It is concluded that NKCa of the tonsils and base of tongue is a distinct subtype of squamous cell carcinoma of the head and neck with high prevalence of HPV DNA and a characteristic immunophenotype.     

HPV analysis in distinguishing second primary tumors from lung metastases in patients with head and neck squamous cell carcinoma

For patients with head and neck squamous cell carcinoma (HNSqCC), the development of squamous cell carcinoma (SqCC) in the lung may signal a new primary or the onset of metastatic dissemination. Although the distinction influences prognosis and therapy, it may not be straightforward on histologic or clinical grounds. The human papillomavirus (HPV) is an etiologic agent for SqCCs arising from the oropharynx but not for SqCCs arising from other head and neck sites. For patients with HNSqCC who develop a lung SqCC, HPV analysis could be useful in establishing tumor relationships. High-risk HPV in situ hybridization was performed on 54 lung SqCCs from patients with a previously diagnosed HNSqCC and on 166 primary lung carcinomas from patients without a prior HNSqCC. HPV was detected in 11 of 220 (5%) cases. All HPV-positive cases were from patients with a prior oropharyngeal SqCC. For the paired oropharyngeal and lung SqCCs, HPV status was concordant in 95% of cases. Time from treatment of HPV-positive oropharyngeal carcinomas to detection of lung carcinoma ranged from 1 to 97 months (mean, 36 mo). Two HPV-positive cancers were detected in the lung 8 years after treatment of the oropharyngeal primary. Despite the long interval, E6 sequencing analysis of 1 of these paired samples confirmed that the tumors harbored the same HPV-16 variant. HPV does not seem to play a role in the development of primary lung cancer. For patients with oropharyngeal SqCC who develop lung SqCC, HPV analysis may be helpful in clarifying tumor relationships. These relationships may not be obvious on clinical grounds, as HPV-related HNSqCC may metastasize long after treatment of the primary tumor.     

Basaloid squamous cell carcinoma of the head and neck is a mixed variant that can be further resolved by HPV status

Basaloid squamous cell carcinoma (BSCC) of the head and neck is set apart as a distinct subtype of squamous cell carcinoma on the basis of its basaloid appearance and aggressive behavior. The purpose of this study was to determine whether BSCC could be further subdivided on the basis of human papillomavirus 16 (HPV16) status. HPV16 in situ hybridization was performed on 53 BSCCs of the head and neck. Of the 53 BSCCs, 21 (40%) arose in the oropharynx and 32 (60%) arose in nonoropharyngeal sites. HPV16 was detected in 34% of BSCCs overall, but the frequency varied by site. HPV16 was detected in 16 of 21 (76%) BSCCs of the oropharynx, but in only 2 of 32 (6%) BSCCs from nonoropharyngeal sites (P<0.0001, Fisher exact). The absence of HPV16 was significantly associated with decreased overall survival (Hazard ratio=17.1; 95% confidence interval=7.2-40.3, log-rank P=0.0001), even though patients with HPV16-positive carcinomas were more likely to present with lymph nodes metastases (P=0.01, Fisher exact). Morphologic similarities aside, BSCCs are composed of a mixed group of tumors that can be separated on the basis of HPV16 status. The distinction is important. HPV16-positivity in squamous cell carcinomas of the head and neck is now recognized as a powerful indicator of improved patient survival. HPV16 detection thus permits resolution of a less aggressive component within a high-grade subtype of head and neck carcinoma.     

Human papillomavirus DNA sequences in cell lines derived from head and neck squamous cell carcinomas.

There is increasing evidence that human papillomaviruses (HPV) have a casual role in some neoplasms in human beings. As examples, DNA of HPV types 16, 18, and 31 are frequently present in genital cancers in humans. Recently, oncogenic HPV types have also been identified in neoplasms of the head and neck, including verrucous carcinoma of the larynx, squamous cell carcinomas of the oral cavity and larynx, and inverted papillomas of the nose. These findings and our resource of an extensive panel of head and neck squamous cell carcinoma (HNSCC) cell lines led us to begin to investigate how frequently HPV DNA was present in these tumor cell lines. For initial analysis, twenty-two HNSCC cell lines derived from 20 patients' tumors were selected as representative of our tumor cell line panel with respect to diversity of primary site, tumor stage, patient age, sex, and clinical course. For Southern analysis, cell line DNA was tested for hybridization with DNA probes for HPV types 6, 11, 16, 18, and 31. Polymerase chain reaction (PCR) analysis was also performed on five tumor cell lines using types 6, 11, 16, 18, and 52 as probes. Southern blot analysis revealed HPV-specific signals in two of the 22 HNSCC cell lines tested. One of these, UM-SCC-23, was HPV 31 positive, which to our knowledge is the first identification of HPV 31 in HNSCC. UM-SCC-63, the other HPV-positive tumor identified by Southern analysis, hybridized with both type 18 and 31. Of the five tumor cell lines tested with PCR, two were HPV positive.(ABSTRACT TRUNCATED AT 250 WORDS)     

Human papillomavirus infections in laryngeal cancer

Although the association and clinical significance of human papillomavirus (HPV) infections with a subset of head and neck cancers, particularly for oropharyngeal carcinoma, has recently been well documented, the involvement of HPV in laryngeal cancer has been inadequately evaluated. Herein we review the currently known associations of HPV infections in diseases of the larynx and their potential for oncogenicity. Using several methods of detection, HPV DNA has been detected in benign (papillomatosis), indolent (verrucous carcinoma), and malignant (squamous cell carcinoma) lesions of the larynx. Consistent with the known oncogenic risk of HPV infections, common HPV types associated with laryngeal papillomatosis include low‐risk HPV types 6 and 11, with high‐risk HPV types 16 and 18 more commonly present in neoplastic lesions (verrucous carcinoma and squamous cell carcinoma). Although a broad range of prevalence has been noted in individual studies, approximately 25% of laryngeal squamous cell carcinomas harbor HPV infections on meta‐analysis, with common involvement of high‐risk HPV types 16 (highest frequency) and 18. Preliminary results suggest that these high‐risk HPV infections seem to be biologically relevant in laryngeal carcinogenesis, manifested as having viral DNA integration in the cancer cell genome and increased expression of the p16 protein. Despite this knowledge, the clinical significance of these infections and the implications on disease prevention and treatment are unclear and require further investigation. © 2010 Wiley Periodicals, Inc. Head Neck, 2011     

The expression of key cell cycle markers and presence of human papillomavirus in squamous cell carcinoma of the tonsil

BACKGROUND: Chemical carcinogens induce squamous cell carcinoma (SCC) of the head and neck by targeting the p53 and the retinoblastoma (pRb) pathways. Human papillomavirus (HPV) might have an etiologic role in these cancers at particular sites. Few studies have compared cell cycle protein expression in HPV-positive and HPV-negative tumors in this region. METHODS: Fifty tonsil SCCs were analyzed for HPV by PCR and for expression of cell cycle proteins (p53, pRb, p16(INK4A), p21(CIP1/WAF1), p27(KIP1), and cyclinD1) by immunohistochemistry. RESULTS: HPV was present in 42%; almost all were type 16. There were statistical associations between HPV positivity and reduced expression of pRb and cyclinD1, overexpression of p16, and younger patient age. Tumor with down-regulated p27 tended to have down-regulated pRb and p21. CONCLUSIONS: HPV-positive tonsil SCCs have distinct molecular pathways. Their association with younger patient age suggests that they are biologically distinct from HPV-negative tumors.     

Relationship of human papillomavirus to ploidy in squamous cell carcinomas of the head and neck.

To establish the relationship between the presence of human papillomavirus (HPV) gene sequences and the development of genetic abnormalities, 31 squamous cell carcinomas of the head and neck were studied for the presence of HPV types 6b and 16 and the DNA content by flow cytometry. Eighteen (58%) cases were aneuploid. HPV DNA was present in seven (22.5%) tumors. Five of them were positive for the HPV type 6b and two for the HPV type 16. Aneuploidy was correlated with poorly differentiated tumors. No correlation was found between the presence of HPV, DNA content, or tumor differentiation. Consequently, the presence of HPV gene sequences does not seem to be related to a higher incidence of genetic abnormalities in squamous cell carcinomas of the head and neck.     

Human papillomavirus and gene mutations in head and neck squamous carcinomas

Background: Human papillomavirus (HPV) infection is implicated as an aetiological factor in head and neck squamous carcinomas (HNSCC), especially in the tonsils of the oropharyngeal region. This study investigates the frequency of HPV infection, p16 and p53 tumour profile and mutations in epidermal growth factor receptor (EGFR), Kirsten RNA Associated Rat Sarcoma 2 Virus (KRAS) and B‐Raf proto‐oncogene serine/threonine protein kinase (BRAF) genes in tonsillar and non‐tonsillar HNSCCs and correlates with clinical outcome and histopathological parameters in previously unstudied cohort of patients. Methods: A retrospective clinical study was performed utilising the demographic data and pathological specimens from 60 out of 726 head and neck cancer patients. Smoking and alcohol history, tumour staging, treatment and outcomes were recorded. Histopathology and immunochemistry for p16 and p53 was performed and HPV DNA was detected with polymerase chain reaction. Genomic DNA from all cancers were analysed for somatic mutations of EGFR, BRAF and KRAS genes. Results: 20 (33%) of 60 cases were tonsillar squamous carcinomas and 38 (66%) were non‐tonsillar. 19 (95%) of the 20 tonsillar cancers and three (8%) of 38 non‐tonsillar patients were patients who were HPV 16‐positive. Nine (47%) of the 19 HPV 16‐positive tonsillar cases were p16 positive. Gene mutations were rare. There was a statistically significant (P < 0.05) improved survival of patients with HPV positive tonsillar tumours, younger age and non‐smokers. Conclusion: Although limited in numbers, this study reinforces the role of HPV infection in HNSCC and its association with a more favourable clinical course in younger non‐smokers worldwide. Gene mutation frequencies were low in all cancers tested and routine testing not recommended.     

Human papillomavirus infection in "young" versus "old" patients with squamous cell carcinoma of the head and neck

BACKGROUND: Human papillomavirus (HPV) represents a potential risk factor for squamous cell cancer of the head and neck (SCCHN). We evaluated the prevalence of HPV DNA in patients with SCCHN diagnosed at the University of Michigan from 1994-1996. METHODS: Patients were stratified by age at diagnosis as "young" (<50 years; median, 39) or "old" (>50 years; median, 66). Fourteen "young" and 14 "old" were matched for tumor site, and 4 additional "old" patients were included. Specimens were analyzed by polymerase chain reaction for HPV DNA using 2 sets of consensus primers. HPV sequences were confirmed by Southern blot hybridization and typed with type-specific probes. RESULTS: Overall, 15 of 32 (46.9%) samples contained HPV sequences. HPV 16 was detected in 9 of 15 (60%), HPV-18 in 1 of 15 (6.6%), and 5 of 15 (33.3%) remained untyped by multiple methods. When stratified, 7 of 14 (50%) "young" were HPV-positive compared with 8 of 18 (44.4%) "old" (p =.76). Survival in patients with HPV-positive SCCHN was significantly longer than that for HPV-negative patients. CONCLUSIONS: The incidence of HPV in "young" versus "old" is not significantly different, suggesting similar roles for both groups. Patients with HPV-positive tumors may have a survival advantage relative to patients with HPV-negative tumors.     

Gene Expression Characterization of HPV Positive Head and Neck Cancer to Predict Response to Chemoradiation

Human papillomavirus (HPV) has been shown to have a causal role in the development of head and neck squamous cell carcinoma. While HPV-positive head and neck cancer is associated with a better response to treatment in the majority of patients, there is a subset who does not respond favorably to current therapy. Identification of these patients could prevent unnecessary morbidity and indicate the need for alternative therapeutic options. Tissue samples were obtained from 19 patients with HPV-positive head and neck squamous carcinoma treated with chemoradiation therapy. HPV status was confirmed by polymerase chain reaction analysis through detection of HPV16 E7 in both DNA and RNA. RNA was isolated from tissue samples and subjected to microarray gene expression analysis. In addition to identification of potential genetic biomarkers (including LCE3D, KRTDAP, HMOX1, KRT19, MDK, TSPAN1), differentially expressed genes associated with genomic stability, cell cycle, and DNA damage were detected between responders and non-responders. These results were further validated with publicly available gene expression studies. This pilot study suggests prospective biomarkers that predict response to therapy. The importance of genes involved with genomic stability is highlighted in both development and progression of head and neck squamous cell carcinoma but also recurrence. Potential development of an assay may prove beneficial to clinicians, assisting them to provide alternative care sooner thus lowering morbidity.

Electronic supplementary material

The online version of this article (doi:10.1007/s12105-014-0597-6) contains supplementary material, which is available to authorized users.     

Tonsillectomy in diagnosis of the unknown primary tumor of the head and neck.

OBJECTIVES: The purpose of this study was to discuss the experience of one tumor registry with performing tonsillectomy in the diagnostic approach to unknown head and neck primary tumors. It also describes the importance of including tonsillectomy in this evaluation algorithm. STUDY DESIGN: A retrospective chart review was done of 68 patients with either tonsillar or unknown primary squamous cell carcinoma culled from 829 patients seen from 1956 to 1996 at the head and neck tumor registry at the Naval Medical Center San Diego. METHODS: Records from the head and neck tumor registry, radiation oncology service, and pathology department were reviewed with attention to presenting symptom, initial examination, diagnostic studies performed, and type and result of biopsies performed. RESULTS: Thirty-four patients sought treatment for a neck lymph node metastasis of squamous cell carcinoma without an identifiable primary tumor site. Six of these (18%) had the primary site diagnosed by performing tonsillectomy ipsilateral to the presenting neck mass. Six of 14 T1 tonsillar carcinomas in this series had the primary site identified by tonsillectomy. CONCLUSIONS: Despite a diligent search, a primary tumor site may not be found in the head and neck cancer patient. The tonsil may harbor an occult squamous cell carcinoma. The patient benefits from identification of the initial tumor site because postoperative irradiation ports may be reduced and because surveillance for recurrence may be improved. For these reasons, tonsillectomy should be performed ipsilateral to the presenting cervical metastasis if no other primary tumor site is identified.     

Human Papillomavirus and Epstein Barr Virus in Head and Neck Carcinomas: Suggestions for the New WHO Classification

In the 9 years since the last World Health Organization (WHO) classification for head and neck tumors, a great deal has changed. In particular, human papillomavirus (HPV) has emerged as the major etiologic agent and patient prognostic marker for squamous cell carcinoma, most profoundly in the oropharynx. It also casts a long shadow over all of the rest of head and neck cancer given its biologic and prognostic implications. By contrast, little has changed regarding our knowledge of Epstein–Barr virus in head and neck cancers, except as it relates to HPV in nonkeratinizing-type nasopharyngeal carcinomas. This article discusses some of the major advances in our understanding of virus-related squamous cell carcinoma of the head and neck and suggests several specific concepts and terminology for incorporation into the next WHO classification.     

Human Papillomavirus-Associated Head and Neck Squamous Cell Carcinoma Survival: A Comparison by Tumor Site and Initial Treatment

Recent evidence suggests that human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) patients have better survival than HPV-negative patients. However, it is unclear if similar patterns for survival exist across different tumor sites, and whether HPV-associated prognosis is modified by type of treatment. We prospectively tested 222 histologically confirmed HNSCC primary tumors for HPV DNA by PCR and HPV E6/E7 RNA by RT-PCR prior to treatment at a large urban health center. Cox proportional hazard ratio models were constructed to assess HPV-associated differences in overall and disease-specific survival adjusting for clinical and demographic covariates. HPV detection varied significantly by primary HNSCC tumor site, from 35 % for oropharynx, to 25 % for hypopharynx, 5 % for larynx, and 3 % for oral cavity (p < 0.0001), with HPV16 accounting for the majority (95 %) of HPV-positive tumors. The hazard-risk of overall and disease-specific death comparing HPV16-positive versus negative oropharyngeal HNSCC was reduced by 74 and 89 %, respectively (p values < 0.05), and was independent of other prognostic indicators; no statistically significant changes in outcomes were observed for non-oropharyngeal HNSCC sites. Prediction of overall survival was better with combined DNA and RNA HPV16 positive PCR detection. There was no difference in HPV16-associated survival whether patients received either surgery or (chemo)radiotherapy as their initial treatment modality. Improved HPV-associated HNSCC survival is limited to patients with oropharyngeal primaries. No selective treatment advantage is observed for HPV-positive tumors, although clinical trials are needed to evaluate which treatment modalities provide the most benefit for HPV-positive HNSCC.     

Human Papillomavirus (HPV) Related Carcinomas of the Upper Aerodigestive Tract

Epidemiologic, clinical, morphologic and molecular evidence show that high risk HPV, particularly type 16, is a prerequisite for some carcinomas of the upper aerodigestive tract (UADT), particularly tonsil and base of tongue. Sexual transmission is an important mode of infection while tobacco use and excessive drinking are not considered risk factors. HPV + tumors are distinct clinically and pathologically. They are more common in young patients (<40 years) with a male to female ratio of 4:1. They usually present as a small or occult primary tumor with advanced neck disease. Microscopically they are non-keratinizing squamous cell carcinomas with basaloid features, excessive mitosis and comedo type necrosis. The tumors have a distinct immunohistochemical profile characterized by strong and diffuse p16 reactivity, low or negative p53 staining and high Ki67 labeling scores. HPV + carcinomas are more radio-sensitive and have a better prognosis than the classical keratinizing SCC of the UADT. An anti-HPV vaccine has recently been made available for prevention of cervical cancer. The impact of the vaccine on the prevalence of HPV related carcinomas of the UADT is currently not known but likely beneficial.     

Sinonasal Squamous Cell Carcinoma: A Review with Emphasis on Emerging Histologic Subtypes and the Role of Human Papillomavirus

The sinonasal tract is one of the least frequent sites for squamous cell carcinoma in the head and neck. However, it is still a complex tumor type for pathologists because there are numerous histologic variants with unusual morphologic features, several non-squamous carcinomas in the differential diagnosis that can have similar morphology and even squamous differentiation, and because of the increasing recognition of human papillomavirus (HPV) in a subset of the tumors. In addition, the unique and complex anatomy of the sinonasal tract can make proper staging and management of patients’ tumors quite challenging. This article reviews sinonasal tract squamous cell carcinoma in depth and provides the latest data on Schneiderian papillomas and HPV in their pathogenesis.     

Loss of expression of ZAC/LOT1 in squamous cell carcinomas of head and neck

BACKGROUND: ZAC/Lot1 is a previously identified candidate tumor suppressor gene. The gene maps to the human chromosome 6q24-q25, a region frequently deleted in squamous cell carcinomas of the head and neck and other solid tumors. METHODS: We have used a model of head and neck squamous cell carcinoma (HNSCC) and cell lines to analyze the role of the candidate tumor suppressor gene ZAC/Lot1 in oral carcinogenesis. We analyzed the expression in 11 cell lines, and we performed loss of heterozygosity (LOH)- and sequence analyses in 51 primary tumors. RESULTS: Three (27.3%) of 11 cell lines showed a distinctly reduced expression of ZAC/Lot1 compared with expression levels of the gene in the normal oral mucosa. In addition, we analyzed 51 primary squamous cell carcinomas of the head and neck for LOH with seven microsatellite markers flanking ZAC/Lot1. We detected an average LOH rate of 31.4% in the region of interest. Sequence analysis revealed no mutations for the ZAC/Lot1 coding exons, including the exon/intron boundaries. CONCLUSIONS: These data could suggest a minimal role for ZAC/Lot1 in a subgroup of HNSCC tumors.