Basaloid squamous cell carcinoma of the head and neck is a mixed variant that can be further resolved by HPV status. Am J Surg Pathol. 2008;32:1044-1050. [PMID: 18496144 DOI: 10.1097/pas.0b013e31816380ec]

Human Papillomavirus Testing in Head and Neck Carcinomas: Guideline Update

CONTEXT.—

In 2018, an evidence-based guideline was published by the College of American Pathologists to develop recommendations for the testing, application, interpretation, and reporting of high-risk human papillomavirus and surrogate marker tests in head and neck carcinomas. Substantial new evidence has prompted a review, including data on human papillomavirus (HPV) in nonoropharyngeal anatomic sites, HPV global rates, p16 immunohistochemistry, and HPV testing performance in cytology specimens, and performance of p16 immunohistochemistry as a surrogate marker.

OBJECTIVE.—

To assess research published since the release of the original 2018 guideline and to update evidence-based recommendations for HPV testing in head and neck carcinomas.

DESIGN.—

The College of American Pathologists convened a panel of experts to update the guideline following the standards established by the National Academy of Medicine for developing trustworthy clinical practice guidelines. The expert panel defined the key questions and performed a systematic review of the literature. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, recommendations were updated on the basis of available evidence, certainty of that evidence, and key judgments.

RESULTS.—

Seven strong recommendations, 4 conditional recommendations, and 5 good practice statements are offered in the guideline update.

CONCLUSIONS.—

The updated guideline statements provide direction on the nature of HPV testing in various head and neck specimens (including key updates based on new research on sinonasal squamous cell carcinoma) and expanded guidance on specific scenarios and practice settings. The goal is to improve and standardize, where possible, HPV testing across diverse pathology practice settings and different countries.

Hiding in plain sight: NUT carcinoma is an unrecognized subtype of squamous cell carcinoma of the lungs and head and neck

In the past two decades, treatment for non-small-cell lung cancers (NSCLCs) and head and neck squamous cell carcinoma (HNSCC) has advanced considerably, owing largely to the characterization of distinct oncological subtypes, the development of targeted therapies for each subtype and the advent of immunotherapy. Data emerging over the past two decades suggest that NUT carcinoma, a highly aggressive malignancy driven by a NUT fusion oncoprotein and arising in the lungs, head and neck, and rarely in other sites, is a squamous cell carcinoma (SCC) based on transcriptional, histopathological, cell-of-origin and molecular characteristics. NUT carcinoma has an estimated incidence of 1,400 cases per year in the United States, surpassing that of some rare NSCLC and HNSCC subtypes. However, NUT carcinoma is currently not recognized as an SCC of the lungs or head and neck. The orphan classification of NUT carcinoma as a distinct entity leads to a lack of awareness of this malignancy among oncologists and surgeons, despite early diagnosis being crucial for this cancer type with a median survival of only ~6.5 months. Consequently, NUT carcinoma is underdiagnosed and often misdiagnosed, resulting in limited research and progress in developing effective treatments in one of the most aggressive forms of lung and head and neck cancer. With a growing number of targeted agents that can potentially be used to treat NUT carcinoma, improved recognition through reclassification and inclusion of NUT carcinoma as a squamous NSCLC or an HNSCC when arising in these locations will accelerate the development of effective therapies for this disease. Thus, in the Perspective, we propose such a reclassification of NUT carcinoma as an SCC and discuss the supporting evidence.

The impact of histopathology on prognosis of squamous cell carcinoma of the larynx: can we do better?

Despite decades of progress, laryngeal squamous cell carcinoma (SCC) is still associated with significant morbidity and mortality worldwide. Additional biomarkers are needed to apply precision medicine and predict the clinical course. We reviewed and summarised routinely reported histopathologic features (e.g. subtypes of laryngeal SCC) along with promising potential biomarkers not yet routinely assessed using international guidelines. These include extra- vs intratumoural vascular and perineural invasion, tumour budding, depth of invasion, and tumour-infiltrating lymphocytes. We also address the problem of specimen quality and type (open approach vs endoscopic surgery) and the related limitations. High-risk human papillomavirus infection is another controversial issue to be discussed, being rare in laryngeal SCC, with an indeterminate prognostic significance and less reliable p16 overexpression as a surrogate marker of HPV infection. Further studies are warranted to address the applicability and to see which of the described parameters may help to better stratify patients with laryngeal SCC and should therefore be included in the pathology report.

Histomorphology based prediction of p16 immunopositivity and p16/HPV DNA co-positivity in oral squamous cell carcinoma

The histomorphological features predictive of p16 and human papilloma virus (HPV DNA) positivity in oropharyngeal carcinoma have been a matter of much debate. However, only few studies have been done on oral squamous cell carcinoma (OSCC) to correlate the histomorphological features with p16 and HPV DNA positivity. Oral squamous cell carcinoma has distinct etiopathogenesis, treatment and prognosis as compared to oropharyngeal carcinomas. A total of 800 oral squamous cell carcinoma biopsy cases were evaluated for features suggestive of HPV infection like basaloid appearance, absence of stromal reaction, nests and lobules of tumor cells with pushing borders, central necrosis, lympho-epithelial morphology, koilocytes, and non-keratinizing or hybrid morphology. Immunohistochemistry was performed for p16 expression (E6H4 clone, CINtec histology, Roche diagnostics). The cases which showed 2+/3+ (from moderate to high intensity) staining with >75 % cells were considered as p16 immunopositive. All the p16 immunopositive cases were subjected to real-time PCR (polymerase chain reaction) for HPV DNA detection to confirm HPV positivity. A total of 139 (17.37 %) OSCC cases were p16 immunopositive and out of these 104 (104/139, 74.8 %) cases showed HPV-DNA PCR positivity. None of the features were found to be predictive on multivariate logistic regression analysis. However, on bivariable analysis, nest/lobule with pushing border was the only histopathological feature which had a significant correlation with p16 immunopositivity (P value = 0.0001) and p16 and HPV DNA copositivity (P value = 0.0001). (Fisher's exact test -two tailed). To conclude-morphology is not really predictive of HPV positivity in OSCC cases. Only one feature- nests and lobule with pushing border is suggestive on bivariable analysis.

A Rare Case of Primary Cutaneous Basaloid Squamous Cell Carcinoma of the Finger

Abstract is missing (Short communication)

Desmoplastic Small Round Cell Tumor of the Head and Neck: A Potential Diagnostic Pitfall

Primary desmoplastic small round cell tumor (DSRCT) in the head and neck region is extremely rare. There is limited information about its clinicopathological characteristics, prognosis, and treatment modalities. The purpose of this study is to provide a comprehensive review of DSRCT occurring primarily in the head and neck, to demonstrate its peculiar morphology and immunohistochemical expression, and to address the differential diagnoses. A total of 25 cases were collected after a thorough review of the relevant literature. DSRCT was most frequently reported in the major salivary glands, followed by the eyes. Furthermore, some cases were misinterpreted as poorly differentiated carcinoma, Ewing sarcoma, and olfactory neuroblastoma. Diagnosing DSRCTs in the head and neck can be very challenging due to their rarity in this location, overlapping morphology, and immunohistochemistry. In these cases, following a systemic approach helps to solve diagnostic problems.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: Hypopharynx, Larynx, Trachea and Parapharyngeal Space

In this article, we review the chapter on tumors of the larynx, hypopharynx, trachea and parapharyngeal space in the new edition of the WHO book, focusing on the new developments in comparison to the previous edition. Squamous cell carcinoma (SCC) and its variants are by far the most common malignancies at these locations, with very limited new insights. The most important is the introduction of new targeted treatment-checkpoint inhibitors, with a new task for pathologists, who may help to predict the response to treatment by analyzing the expression of targeted proteins in biopsy samples. Precancerous lesions remain a controversial topic and, similarly to other organs, it is acceptable to use the terms "dysplasia" or "squamous intraepithelial lesion" (SIL), but there is a slight difference between low-grade dysplasia and low-grade SIL: in the former, mild atypia must be present, while the latter also includes hyperplastic epithelium without atypia. Two approaches have been proposed: a two-tiered system with low- and high-grade dysplasia/SIL and a three-tiered system with an additional category, carcinoma in situ. We are still searching for reliable diagnostic markers to surpass the subjectivity in biopsy diagnosis, with a few potential candidate markers on the horizon, e.g., stem cell markers. Other tumors are rare at these locations, e.g., hematolymphoid, neuroendocrine and salivary gland neoplasms, and are no longer included in Chapter 3. They must be diagnosed according to criteria described in specific chapters. The same holds true for soft tissue tumors, with the exception of cartilaginous neoplasms, which are still included in Chapter 3.

[Clinicopathological study in 28 cases of oral basaloid squamous cell carcinomas]

OBJECTIVE

To investigate the clinicopathologic features and prognostic factors in oral basaloid squamous cell carcinoma.

METHODS

Retrospective analysis of oral basaloid squamous cell carcinomas patients who underwent tumor resection during the period from January 2002 to December 2020 in the authors' hospital, especially the clinicopathologic characteristics of 28 cases with confirmed diagnosis and follow-up data. Immunohistochemistry was performed to define the helpful markers for differentiation diagnosis. The factors influencing the prognosis were evaluated based on Kaplan-Meier method.

RESULTS

The tongue and mouth floor (11 cases, 39.3%) were the most frequently involved sites, followed by gingiva (6 cases, 21.4%), buccal (5 cases, 17.9%), palate (4 cases, 14.3%), and oropharynx (2 cases, 7.1%). The majority of basaloid squamous cell carcinomas were in advanced stage, with 12 cases in stage Ⅱ and 16 cases in stages Ⅲ-Ⅳ. Twelve of 28 patients were identified to have cervical lymph node metastasis, which was confirmed by histopathological examination. The incidence rate of lymph node metastasis was 42.9% (12/28). Nine tumors recurred, with one metastasized to the lung. At the meantime, the 28 conventional squamous cell carcinomas were matched with the same stage, among which 13 cases were identified with cervical lymph node metastasis. The incidence rate of lymph node metastasis was 46.4% (13/28). Five cases recurred, with two cases that metastasized to the lung and one to the brain. The 5-year overall survival rates of the basaloid squamous cell carcinoma and conventional squamous cell carcinoma patients were 54.6% and 53.8%, respectively. Histopathologically, basaloid cells consisted of tumor islands without evident keratinization but frequently with comedo-like necrosis within the tumor islands. CK5/6 and P63 exhibited strongly positive in all the 28 cases, whereas neuroendocrine markers, CgA and Syn, were negative. Eight cases positively expressed P16; one case showed focal SOX10 positive but CK7 negative.

CONCLUSION

The majority of oral basaloid squamous cell carcinomas present in advanced stage with a high tendency to lymph node metastasis, but the overall survival rates are not significantly different from conventional squamous cell carcinomas matched with the same stage. The human papilloma virus (HPV), as HPV-positivity rate is high, correlates to good prognosis. In addition, CK7 & SOX10 immunohistochemistry could contribute to differential diagnosis for basaloid squamous cell carcinoma with solid adenoid cystic carcinoma.

Liquid BIOpsy for MiNimal RESidual DiSease Detection in Head and Neck Squamous Cell Carcinoma (LIONESS)-a personalised circulating tumour DNA analysis in head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) remain a substantial burden to global health. Cell-free circulating tumour DNA (ctDNA) is an emerging biomarker but has not been studied sufficiently in HNSCC.

METHODS

We conducted a single-centre prospective cohort study to investigate ctDNA in patients with p16-negative HNSCC who received curative-intent primary surgical treatment. Whole-exome sequencing was performed on formalin-fixed paraffin-embedded (FFPE) tumour tissue. We utilised RaDaR^TM, a highly sensitive personalised assay using deep sequencing for tumour-specific variants, to analyse serial pre- and post-operative plasma samples for evidence of minimal residual disease and recurrence.

RESULTS

In 17 patients analysed, personalised panels were designed to detect 34 to 52 somatic variants. Data show ctDNA detection in baseline samples taken prior to surgery in 17 of 17 patients. In post-surgery samples, ctDNA could be detected at levels as low as 0.0006% variant allele frequency. In all cases with clinical recurrence to date, ctDNA was detected prior to progression, with lead times ranging from 108 to 253 days.

CONCLUSIONS

This study illustrates the potential of ctDNA as a biomarker for detecting minimal residual disease and recurrence in HNSCC and demonstrates the feasibility of personalised ctDNA assays for the detection of disease prior to clinical recurrence.

Head and Neck Cancers Are Not Alike When Tarred with the Same Brush: An Epigenetic Perspective from the Cancerization Field to Prognosis

Simple Summary

Squamous cell carcinomas affect different head and neck subsites and, although these tumors arise from the same epithelial lining and share risk factors, they differ in terms of clinical behavior and molecular carcinogenesis mechanisms. Differences between HPV-negative and HPV-positive tumors are those most frequently explored, but further data suggest that the molecular heterogeneity observed among head and neck subsites may go beyond HPV infection. In this review, we explore how alterations of DNA methylation and microRNA expression contribute to head and neck squamous cell carcinoma (HNSCC) development and progression. The association of these epigenetic alterations with risk factor exposure, early carcinogenesis steps, transformation risk, and prognosis are described. Finally, we discuss the potential application of the use of epigenetic biomarkers in HNSCC.

Abstract

Head and neck squamous cell carcinomas (HNSCC) are among the ten most frequent types of cancer worldwide and, despite all efforts, are still diagnosed at late stages and show poor overall survival. Furthermore, HNSCC patients often experience relapses and the development of second primary tumors, as a consequence of the field cancerization process. Therefore, a better comprehension of the molecular mechanisms involved in HNSCC development and progression may enable diagnosis anticipation and provide valuable tools for prediction of prognosis and response to therapy. However, the different biological behavior of these tumors depending on the affected anatomical site and risk factor exposure, as well as the high genetic heterogeneity observed in HNSCC are major obstacles in this pursue. In this context, epigenetic alterations have been shown to be common in HNSCC, to discriminate the tumor anatomical subsites, to be responsive to risk factor exposure, and show promising results in biomarker development. Based on this, this review brings together the current knowledge on alterations of DNA methylation and microRNA expression in HNSCC natural history, focusing on how they contribute to each step of the process and on their applicability as biomarkers of exposure, HNSCC development, progression, and response to therapy.

Undifferentiated and dedifferentiated head and neck carcinomas

Undifferentiated carcinomas arising at salivary gland and head and neck mucosal sites may originate either de novo or through a process of dedifferentiation of a differentiated carcinoma. While in the latter group the diagnosis is largely dependent on the identification of the differentiated component or recognition of a specific genotype, the classification of undifferentiated carcinomas that lack a differentiated component is mainly based on the identification of specific genetic drivers, like for example the NUTM1 fusions in NUT carcinoma. A further category is represented by virus associated carcinomas (mainly HPV and EBV), that frequently displays an undifferentiated morphology. Overall, these tumors often represent a diagnostic challenge, especially in small biopsies. This review summarizes and discuss the diagnostic approach to the main head and neck carcinoma types that frequently or occasionally display an undifferentiated appearance, with a focus on salivary gland, oropharyngeal, nasopharyngeal and sinonasal subsites.

Basaloid squamous cell carcinoma of the hypopharynx: an analysis of 213 cases

PURPOSE

Basaloid squamous cell carcinoma (BSCC) is a rare aggressive variant of squamous cell carcinoma (SCC) with a poor prognosis. No large series of exclusively hypopharyngeal BSCC patients have been previously reported. Therefore, this retrospective population-based study aims to explain the patient demographics, clinicopathologic characteristics, incidence, and survival outcomes of hypopharyngeal BSCC and how it relates to conventional-type SCC.

METHODS

The National Cancer Institute's Surveillance, Epidemiology, and End Results database registry was queried for patients diagnosed with hypopharyngeal BSCC and conventional-type SCC between 2001 and 2016.

RESULTS

The incidence of hypopharyngeal BSCC from 2001 to 2016 was 0.0161 per 100,000 individuals. The BSCC group comprised 213 patients, and the SCC group 7958 patients. The majority of BSCCs were considered high grade (Grade III/IV, 89.58%). Most BSCC patients were diagnosed at an advanced stage (American Joint Committee on Cancer [AJCC] stage IV, 65.38%). The 1-, 5-, and 10-year disease-specific survival (DSS) rates for hypopharyngeal BSCC were 84.10%, 57.40%, and 46.20%, respectively. Multivariate analysis, after adjustment for sex, age, race, tumor location, grade, and AJCC stage, showed that patients with BSCC had significantly better DSS than those with conventional-type SCC. Surgery with radiation contributed to a favorable DSS for BSCC patients in comparison with other treatments.

CONCLUSION

This analysis of the largest hypopharyngeal BSCC series indicates a better prognosis for this pathologic type compared with conventional-type hypopharyngeal SCC. Multimodality treatment with surgery and radiation may result in a favorable prognosis for hypopharyngeal BSCC patients.

Endogenous APOBEC3B overexpression characterizes HPV-positive and HPV-negative oral epithelial dysplasias and head and neck cancers

The DNA cytosine deaminase APOBEC3B (A3B) is a newly recognized endogenous source of mutations in a range of human tumors, including head/neck cancer. A3B inflicts C-to-T and C-to-G base substitutions in 5'-TCA/T trinucleotide motifs, contributes to accelerated rates of tumor development, and affects clinical outcomes in a variety of cancer types. High-risk human papillomavirus (HPV) infection causes A3B overexpression, and HPV-positive cervical and head/neck cancers are among tumor types with the highest degree of APOBEC signature mutations. A3B overexpression in HPV-positive tumor types is caused by the viral E6/E7 oncoproteins and may be an early off-to-on switch in tumorigenesis. In comparison, less is known about the molecular mechanisms responsible for A3B overexpression in HPV-negative head/neck cancers. Here, we utilize an immunohistochemical approach to determine whether A3B is turned from off-to-on or if it undergoes a more gradual transition to overexpression in HPV-negative head/neck cancers. As positive controls, almost all HPV-positive oral epithelial dysplasias and oropharyngeal cancers showed high levels of nuclear A3B staining regardless of diagnosis. As negative controls, A3B levels were low in phenotypically normal epithelium adjacent to cancer and oral epithelial hyperplasias. Interestingly, HPV-negative and low-grade oral epithelial dysplasias showed intermediate A3B levels, while high-grade oral dysplasias showed high A3B levels similar to oral squamous cell carcinomas. A3B levels were highest in grade 2 and grade 3 oral squamous cell carcinomas. In addition, a strong positive association was found between nuclear A3B and Ki67 scores suggesting a linkage to the cell cycle. Overall, these results support a model in which gradual activation of A3B expression occurs during HPV-negative tumor development and suggest that A3B overexpression may provide a marker for advanced grade oral dysplasia and cancer.

Does P16 Protein Expression Affect Treatment Prognosis in Oral Squamous Cell Carcinoma - A Comparative Study

INTRODUCTION

P16 is an independent and reliable surrogate for the detection of human papillomavirus (HPV) in oral squamous cell carcinoma (OSCC). The aim of this study was to assess the P16 expression as a marker for HPV infection in OSCC and its impact on the treatment outcome.

METHODS AND MATERIALS

A cross-sectional study was conducted on patients with a definite diagnosis of OSCC. Patients were assigned into two groups with and without recurrence or metastasis. Tumour resection was performed in the same manner for all patients. P16 expression was evaluated by immunohistochemical staining. Independent t-test and Chi-square tests were used to find significant differences in age, gender, stage of the disease, tumour size, lymph node involvement, and P16 expression between the two groups.

RESULTS

Of 50 patients, 37 did not show any recurrence or metastasis (group 1), while 13 had a relapse (group 2). There was no significant difference for age, gender distribution, stage of the disease, or lymph node involvement between the two groups (P > 0.05). A significant difference in tumour size was noted between the two groups (P = 0.001). The mean expression of P16 was 38.92 ± 24.36 in group 1 and 51.54 ± 33.63 in group 2. No significant difference was found between the two groups for the mean expression of P16 (P = 0.23).

DISCUSSION

A review of the recent literature revealed that the HPV role in OSCC treatment is controversial. According to the results of this study, there was no significant difference in terms of P16 expression between OSCC patients with and without recurrence or metastasis.

CYLD mutation characterizes a subset of HPV-positive head and neck squamous cell carcinomas with distinctive genomics and frequent cylindroma-like histologic features

Mutations in the tumor suppressor CYLD, known to be causative of cylindromas, were recently described in a subset of high-risk (hr) HPV-positive head and neck squamous cell carcinomas (HNSCC). Pathologic and genetic characterization of these CYLD-mutant carcinomas, however, remains limited. Here, we investigated whether CYLD mutations characterize a histopathologically and genomically distinct subset of hrHPV-positive HNSCC. Comprehensive genomic profiling via hybrid capture-based DNA sequencing was performed on 703 consecutive head and neck carcinomas with hrHPV sequences, identifying 148 unique cases (21%) harboring CYLD mutations. Clinical data, pathology reports, and histopathology were reviewed. CYLD mutations included homozygous deletions (n = 61/148; 41%), truncations (n = 52; 35%), missense (n = 26; 18%) and splice-site (n = 9; 6%) mutations, and in-frame deletion (n = 1; 1%). Among hrHPV-positive HNSCC, the CYLD-mutant cohort showed substantially lower tumor mutational burden than CYLD-wildtype cases (n = 555) (median 2.6 vs. 4.4 mut/Mb, p < 0.00001) and less frequent alterations in PIK3CA (11% vs. 34%, p < 0.0001), KMT2D (1% vs. 16%, p < 0.0001), and FBXW7 (3% vs. 11%, p = 0.0018). Male predominance (94% vs. 87%), median age (58 vs. 60 years), and detection of HPV16 (95% vs. 89%) were similar. On available histopathology, 70% of CYLD-mutant HNSCC (98/141 cases) contained hyalinized material, consistent with basement membrane inclusions, within crowded aggregates of tumor cells. Only 7% of CYLD-wildtype cases demonstrated this distinctive pattern (p < 0.0001). Histopathologic patterns of CYLD-mutant HNSCC lacking basement membrane inclusions included nonkeratinizing (n = 22, 16%), predominantly nonkeratinizing (nonkeratinizing SCC with focal maturation; n = 10, 7%), and keratinizing (n = 11, 8%) patterns. The latter two groups showed significantly higher frequency of PTEN alterations compared with other CYLD-mutant cases (38% [8/21] vs. 7% [8/120], p = 0.0004). Within our cohort of hrHPV-positive HNSCCs, CYLD mutations were frequent (21%) and demonstrated distinctive clinical, histopathologic, and genomic features that may inform future study of prognosis and treatment.

Human papillomavirus genotype distribution in head and neck cancer: Informing developing strategies for cancer prevention, diagnosis, treatment and surveillance

Current clinical practice algorithms for HPV testing make no effort to discern the impact of genotypes for patients with head and neck squamous cell carcinoma (HNSC). Data was collected for all patients with HNSCs that had undergone HPV testing at an academic hospital as part of clinical care (2012-2019). Screening was performed using real-time PCR targeting L1 of low and high-risk HPV types, followed by genotyping of positive cases. Genotype status was correlated with age, site and histologic parameters. Of the 964 patients tested, 68% had HPV-positive cancers. Most arose from the oropharynx (OP) (89%) and sinonasal tract (5%). The most frequent genotype was 16 (84.4%) followed by 35 (5.6%), 33 (4.1%), 18 (2.7%), 45 (1.1%), 69 (0.8%) and others (1.3%). There was an association between genotype (16 vs non-16) and tumor origin (OP vs non-OP) (p < 0.0001). HPV18 was associated with transformation to an aggressive small cell phenotype, but HPV16 was not (22% vs 0%, p < 0.0001). Patients with HPV-non-16 OP carcinomas were older than patients with HPV16 OP carcinomas, but the difference was not significant. HPV genotypes are variable and unevenly distributed across anatomic sites of the head and neck. The association of HPV18 with small cell transformation suggests that variants can track with certain phenotypes in ways that may account for differences in clinical behavior. This study challenges the prevailing assumption of HPV equivalency across all high-risk genotypes in ways that may inform preventive, diagnostic, therapeutic and surveillance strategies.

Revisiting a rare disease: Oral cavity basaloid squamous cell carcinoma at a high-volume tertiary center

OBJECTIVES

Rare diseases are often poorly understood, and this study sought to investigate the incidence of a rare disease entity, basaloid squamous cell carcinoma (BSCC) of the oral cavity (OC) at a tertiary care medical center and to assess its clinical outcomes.

METHODS

The aim of this study was to collect data in order to better understand how this rare disease progresses. This was a case series of patients with OC BSCC diagnosed between 2001 and 2018.

RESULTS

10 patients with primary OC BSCC were identified. Average age at diagnosis was 58 years (33-71). The median follow-up period was 11 months. Primary sites included oral tongue (n = 4), floor of mouth (n = 4), hard palate (n = 1), and retromolar trigone (n = 1). A majority (60%) of patients had pathologic T3/T4 tumors. All patients underwent primary surgical treatment. There was an overall 60% mortality rate: 2 died from metastasis at 1- and 3-months postop, 2 from unknown causes, 1 from sepsis at 1 month postop, and 1 from metastatic colon cancer. Average survival for those patients who died was 20.7 months. 4 patients were disease-free at the time of publication.

CONCLUSION

There are few studies in the literature that seek to investigate cases of OC BSCC from a single institution. This is the first detailed case series of BSCC from a single American institution. Survival outcomes in our cohort were poor but demonstrate a variable course of disease burden. This study presents unique information regarding specific pathologic characteristics and patient outcomes for this rare disease.

Oropharyngeal carcinoma: A single institution study of 338 primaries with special reference to high-risk human papillomavirus-mediated carcinoma with aggressive behavior

In a retrospective review, we identified 332 patients with 338 pathologically diagnosed primary oropharyngeal carcinomas (OPC) between January 2013 and March 2020 with known p16/HPV status from a tumor registry at Northwestern Memorial Hospital. The tumors predominantly involved the palatine tonsil (51 %) and the base of the tongue/lingual tonsil (38 %). The most common type of cancer was non-keratinizing squamous cell carcinoma (60 %), and the majority of primaries were p16 positive/HPV-mediated (86 %). A cohort of p16 positive/HPV mediated OPC (27/283, 9.5 %) presented with aggressive clinical behavior, including multiple distant metastases at unusual sites. Tumor size >2 cm and the presence of tumor anaplasia/multinucleation were significantly associated with an increased rate of distant metastases in p16 positive/HPV mediated cases, both in unadjusted and adjusted analyses (all P < 0.05). Of the 332 individuals in the overall cohort, 38 individuals died due to their disease within the observed follow-up time. Among the 283 patients with p16 positive/HPV mediated tumors, survival was estimated at 97 % (95 % CI 95 %, 100 %) at 1 year, 95 % (95 % CI 92 %, 98 %) at 2 years, and 80 % (95 % CI 72 %, 89 %) at 5 years. The presence of tumor anaplasia/multinucleation and distant metastasis were both significantly associated with poorer disease-specific survival in p16 positive/HPV mediated cases (both P < 0.05), with the survival effect of tumor anaplasia/multinucleation likely mediated in part through its association with distant metastasis. For p16 positive/HPV-mediated OPC, age, smoking status, tumor status, and lymph node status were not significantly associated with disease-specific survival in our study.

The importance of adjuvant treatment and primary anatomical site in head and neck basaloid squamous cell carcinoma survival: an analysis of the National Cancer Database

PURPOSE

Basaloid squamous cell carcinoma (BSCC) of the head and neck is an aggressive and highly malignant variant of squamous cell carcinoma that accounts for 2% of head and neck cancers. Previous studies have not analyzed the significance of adjuvant chemoradiation and anatomical site within BSCC subtype and its impact on survival.

METHODS

A cohort of 1999 patients with BSCC of the head and neck was formed from the National Cancer Database and analyzed with descriptive studies, median survival and 5- and 10-year survival. A multivariable Cox hazard regression was performed to determine the prognostic significance of anatomical site and adjuvant therapy.

RESULTS

The most common primary anatomical site was the oropharynx (71.9%) followed by oral cavity (11.5%), larynx (10.1%), hypopharynx (3.5%), esophagus (1.9%), and nasopharynx (1.1%). The presence of metastasis increased the risk of mortality (HR = 2.14; 95% CI 1.40-3.26). Tumors localized to the oropharynx demonstrated better survival compared to all sites except nasopharynx, including the oral cavity (HR = 2.45; 95% CI 1.83-3.29), hypopharynx (HR = 2.58; 95% CI:1.64-4.05), and larynx (HR = 2.89; 95% CI:2.25-3.73). Adjuvant chemoradiation (HR = 0.36; 95% CI 0.23-0.58) and adjuvant radiation (HR = 0.38; 95% CI 0.23-0.64) had better survival outcomes compared to adjuvant chemotherapy. Patients with microscopic margins had better survival outcomes when compared to no surgery (HR = 0.38, 98% Cl 0.23-0.64) while there were no better survival outcomes of patients with macroscopic margins compared to no surgery.

CONCLUSION

This study illustrated that tumors in the oropharynx, lower age, adjuvant chemoradiation and radiation, and microscopic margins were associated with greater survival.

Basaloid squamous cell carcinoma of the breast

Basaloid squamous cell carcinoma (BSCC) is a subtype of squamous cell carcinoma that characteristically occurs in the head and neck, may be related to HPV infection and is usually considered to be aggressive. We present the first description of BSCC of the breast. The tumor exhibited characteristic histologic features of BSCC, including nests of basaloid squamous cells with comedonecrosis, abrupt keratinization, and abundant hyaline basement membrane-like material deposition. The tumor showed immunohistochemical features of triple negativity, diffuse p63 positivity, p16 positivity, and Rb negativity. HPV immunogenotyping was negative. The patient was free of disease after treatment with breast conserving surgery, chemotherapy and radiotherapy. BSCC of the breast should be distinguished from basaloid adenoid cystic carcinoma, triple-negative basal-like breast cancer and nonbasaloid squamous cell carcinoma of the breast based on histology and immunohistochemistry. The prognostic implications of BSCC of the breast should be further studied in larger series.

Identification of PGRMC1 as a Candidate Oncogene for Head and Neck Cancers and Its Involvement in Metabolic Activities

Progesterone Receptor Membrane Component 1 (PGRMC1/Sigma-2 receptor) is located on chromosome Xq21 and encodes a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450, with function in tumor proliferation and chemoresistance. Although the over-expression of PGRMC1 reported in many different types of human cancers, systematic analysis of its oncogenic role of PGRMC1 has not been performed for any cancer. In this work, we analyzed the transcriptomics, genomics, and clinical data of 498 head-neck squamous cell carcinoma (HNSC) samples from the public-accessible database, The Cancer Genome Atlas (TCGA). The Cox regression was performed to calculate the hazard ratio (HR) of PGRMC1 expression as a prognosis feature for overall survival (OS). Our results demonstrated that PGRMC1 expression served as a predictor for worse OS (HR = 1.95, P = 0.0005) in head-neck squamous cell carcinoma. And the over-expression of PGRMC1 was strongly correlated with various metabolic process activity as well as cancer metastasis and cell proliferation features in human head-neck squamous cell carcinoma patient's cohort. Besides, the over-expression and unfavorable prognosis value of PGRMC1 were also observed in many other cancer types. This study provides insights into the potential oncogenic functional significance of PGRMC1 in cancer research.

Diagnostic traps awaiting the head/neck pathologist: "Cytoplasm-poor" neoplasms

CONTEXT

Beyond squamous carcinoma, a variety of diagnostically challenging neoplasms arise within various head and neck sites. This is particularly the situation with neoplasms where little cellular cytoplasm is present to assist the pathologist in categorizing such lesions.

OBJECTIVE

To highlight diagnostic pitfalls that accompanying neoplasms composed primarily of 'cytoplasmically-poor' cells. These pitfalls include morphologic and immunohistochemical traps that emerge from this class of neoplasms.

DATA SOURCES

Selection of pathologic specimens from the author's personal files, and literature review.

CONCLUSIONS

Interpretative pitfalls regarding the histopathology and immunophenotype of small 'cytoplasmically-poor' neoplasms are a diagnostic hazard in head and neck surgical pathology practice, and require knowledge of histomorphologic plasticity and aberrant immunophenotyping.

An update on head and neck cancer: new entities and their histopathology, molecular background, treatment, and outcome

The head and neck region harbor numerous specialized tissues of all lineages giving rise to a plethora of different malignancies. In recent years, new types and subtypes of cancer has been described here due to the recognition of their histological and molecular characteristics. Some have been formally accepted in the most recent classifications from the World Health Organization (WHO) and American Joint Committee on Cancer (AJCC) as distinct diseases due to characteristics in clinical presentation, outcome, and treatment. In particular, this applies to malignancies of the salivary gland, sinonasal tract, and oropharynx. In this overview, we present the most recent developments in the classification, histopathological characteristics, and molecular features of head and neck cancer. The clinical and radiological characteristics, outcome, and treatment options including perspectives for targeted therapies, are discussed.

Basaloid Squamous Cell Carcinoma of the Larynx: A National Cancer Database Analysis

OBJECTIVE

Basaloid squamous cell histology is a rare variant that accounts for about 2% of all head and neck squamous cell laryngeal carcinomas. The purpose of this study was to examine overall survival rates of patients according to treatment, stage, and laryngeal subsite.

STUDY DESIGN

Retrospective analysis.

SETTING

National Cancer Database (NCDB).

SUBJECTS AND METHODS

The NCDB was queried for patients with basaloid squamous cell carcinoma (BSCC) who were treated from 2004 to 2014. Five-year overall survival rates were determined by the Kaplan-Meier method. Univariate and multivariate analysis was used to identify factors correlated with 5-year overall survival.

RESULTS

The NCDB identified 440 patients meeting inclusion criteria. Median follow-up time was 31.2 months. On univariate analysis, the treatment modalities assessed (surgery alone, surgery with radiotherapy, surgery with chemoradiotherapy, radiotherapy, chemoradiotherapy) did not differ in their survival benefit. On multivariate analysis, only chemoradiotherapy (hazard ratio, 0.587; 95% CI, 0.37-0.93; P = .022) was associated with improved survival. All treatment modalities performed similarly between stage I and II tumors ( P = .340) and stage III and IV tumors ( P = .154).

CONCLUSION

This study represents the largest laryngeal BSCC series to date. We found that chemoradiotherapy was associated with improved 5-year overall survival of laryngeal BSCC on multivariate analysis.

SOX10 Immunoexpression in Basaloid Squamous Cell Carcinomas: A Diagnostic Pitfall for Ruling out Salivary Differentiation

SOX10 immunoexpression is increasingly recognized in salivary gland tumors, including but not limited to those with myoepithelial, serous acinar, and intercalated duct differentiation. However, SOX10 expression has not been extensively evaluated in other epithelial tumors that can mimic salivary origin. Basaloid squamous cell carcinoma (SCC) is a unique variant of SCC that shows morphologic overlap with several salivary tumors, including adenoid cystic carcinoma, basal cell adenocarcinoma, and myoepithelial carcinoma. We performed SOX10 immunohistochemistry on 22 basaloid SCCs and 280 non-basaloid SCCs. If tissue was available, we also performed immunohistochemistry for S100 and p16, and in-situ hybridization for high-risk HPV RNA. SOX10 was positive in 13/22 basaloid SCCs (59%), including 5/6 (83%) that were HPV-positive and 6/12 (50%) that were HPV-negative. Only 2/12 basaloid SCC (17%) demonstrated focal S100 expression. All non-basaloid SCCs were SOX10 negative. Frequent positivity for SOX10 in basaloid SCC presents a significant diagnostic pitfall for distinguishing these tumors from various basaloid salivary carcinomas. The preponderance of SOX10 expression in the basaloid variant of HPV-positive SCC also presents a diagnostic challenge in separating it from HPV-related multiphenotypic sinonasal carcinoma. SOX10 may be more broadly considered a marker of basal differentiation and should not be assumed to be specific for salivary origin in epithelial head and neck tumors.

Survival Rates for Patients With Barrett High-grade Dysplasia and Esophageal Adenocarcinoma With or Without Human Papillomavirus Infection

IMPORTANCE

High-risk human papillomavirus (HPV) has been associated with Barrett dysplasia and esophageal adenocarcinoma. Nevertheless, the prognostic significance of esophageal tumor HPV status is unknown.

OBJECTIVE

To determine the association between HPV infection and related biomarkers in high-grade dysplasia or esophageal adenocarcinoma and survival.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective case-control study. The hypothesis was that HPV-associated esophageal tumors would show a favorable prognosis (as in viral-positive head and neck cancers). Pretreatment biopsies were used for HPV DNA determination via polymerase chain reaction, in situ hybridization for E6 and E7 messenger RNA (mRNA), and immunohistochemistry for the proteins p16INK4A and p53. Sequencing of TP53 was also undertaken. The study took place at secondary and tertiary referral centers, with 151 patients assessed for eligibility and 9 excluded. The study period was from December 1, 2002, to November 28, 2017.

MAIN OUTCOMES AND MEASURES

Disease-free survival (DFS) and overall survival (OS).

RESULTS

Among 142 patients with high-grade dysplasia or esophageal adenocarcinoma (126 [88.7%] male; mean [SD] age, 66.0 [12.1] years; 142 [100%] white), 37 were HPV positive and 105 were HPV negative. Patients who were HPV positive mostly had high p16INK4A expression, low p53 expression, and wild-type TP53. There were more Tis, T1, and T2 tumors in HPV-positive patients compared with HPV-negative patients (75.7% vs 54.3%; difference, 21.4%; 95% CI, 4.6%-38.2%; P = .02). Mean DFS was superior in the HPV-positive group (40.3 vs 24.1 months; difference, 16.2 months; 95% CI, 5.7-26.8; P = .003) as was OS (43.7 vs 29.8 months; difference, 13.9 months; 95% CI, 3.6-24.3; P = .009). Recurrence or progression was reduced in the HPV-positive cohort (24.3% vs 58.1%; difference, -33.8%; 95% CI, -50.5% to -17.0%; P < .001) as was distant metastasis (8.1% vs 27.6%; difference, -19.5%; 95% CI, -31.8% to -7.2%; P = .02) and death from esophageal adenocarcinoma (13.5% vs 36.2%; difference, -22.7%; 95% CI, -37.0% to -8.3%; P = .01). Positive results for HPV and transcriptionally active virus were both associated with a superior DFS (hazard ratio [HR], 0.33; 95% CI, 0.16-0.67; P = .002 and HR, 0.44; 95% CI, 0.22-0.88; P = .02, respectively [log-rank test]). Positivity for E6 and E7 mRNA, high p16INK4A expression, and low p53 expression were not associated with improved DFS. On multivariate analysis, superior DFS was demonstrated for HPV (HR, 0.39; 95% CI, 0.18-0.85; P = .02), biologically active virus (HR, 0.36; 95% CI, 0.15-0.86; P = .02), E6 and E7 mRNA (HR, 0.36; 95% CI, 0.14-0.96; P = .04), and high p16 expression (HR, 0.49; 95% CI, 0.27-0.89; P = .02).

CONCLUSIONS AND RELEVANCE

Barrett high-grade dysplasia and esophageal adenocarcinoma in patients who are positive for HPV are distinct biological entities with a favorable prognosis compared with viral-negative esophageal tumors. Confirmation of these findings in larger cohorts with more advanced disease could present an opportunity for treatment de-escalation in the hope of reducing toxic effects without deleteriously affecting survival.

Laryngeal Basaloid Squamous Cell Carcinoma with a Substantial Spindle Cell Component: Case Presentation and Updated Review of Literature

Basaloid squamous cell carcinoma with spindle cell component is an uncommon aggressive variety of squamous cell carcinoma with only a few reported cases in literature. Histologically a combination of basaloid squamous cell carcinoma and spindle cell squamous cell carcinoma is appreciated and immunohistochemistry serves a role in differentiation from malignant neoplasms of salivary gland or neuro-endocrine origin. Prime treatment modality is combination of surgery and external beam radiotherapy. A case of basaloid squamous cell carcinoma with proliferation of bizarre mesenchymal component is being reported here with an updated literature review.

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.

Human Papillomavirus-Related Neuroendocrine Carcinomas of the Head and Neck

Human papillomavirus (HPV)-related head and neck carcinoma (HNC) represents an important subgroup of head and neck cancer that is characterized by a consistent microscopic appearance and a favorable prognosis. A growing experience with HPV testing, however, has uncovered variants that deviate from the prototypic HPV-HNC with respect to morphology. While these HPV-HNCs may deviate morphologically from the prototype, they do not appear to stray far from the favorable clinical outcome assigned to HPV-positive status. In effect, HPV positivity trumps traditional prognostic features predicated on morphology such as tumor grade and histologic subtype when it comes to predicting clinical behavior. For the diagnostic pathologist, the pedestrian task of tumor grading and subtyping would seem to be of little prognostic or therapeutic relevance when it comes to HPV-HNC. Recognition and documentation of neuroendocrine differentiation is a most notable exception. Forms of HPV-HNC have now been reported that morphologically resemble small cell carcinoma (SCC) and large cell neuroendocrine carcinoma (LCNEC) of other sites, and that immunohistochemically exhibit neuroendocrine differentiation. Despite the presence of HPV, these SCCs and LCNECs share the same aggressive clinical behavior of their counterparts in the lung and other sites where the high grade neuroendocrine phenotype is associated with early distant spread and poor overall survival. Consequently, the high grade neuroendocrine phenotype should be regarded as an aggressive form of HPV-HNC where tumor morphology displaces HPV positivity as the most important prognostic feature.

Updates on Immunohistochemical and Molecular Markers in Selected Head and Neck Diagnostic Problems

CONTEXT

- The head and neck regions have complex anatomic structures. They are not exempted from the rare occurrences of highly unusual, diagnostically challenging malignant neoplasms and mimickers.

OBJECTIVE

- To review and update the utility of immunohistochemistry and molecular biomarkers and to pursue diagnostic accuracy on selected rare neoplasms, especially some poorly differentiated malignancies.

DATA SOURCES

- Personal experience and information from the literature.

CONCLUSIONS

- Head and neck tumors include neoplasms originating from heterogeneous tissue. Using the selected clinical cases, this review illustrates a continuous development of emerging molecular-genetic techniques to assist in the interpretation of uncommon, often poorly differentiated, highly malignant neoplasms. The diagnostic results are appropriately transmitted to the oncologists, radiation oncologists, and surgeons to create a coordinated plan of care for patients with these unusual disorders affecting the head and neck.

A positive-feedback loop between tumour infiltrating activated Treg cells and type 2-skewed macrophages is essential for progression of laryngeal squamous cell carcinoma

BACKGROUND

Foxp3⁺ regulatory T (Treg) cells and M2 macrophages are associated with increased tumour progression. However, the interaction between Treg cells and M2 macrophages remains unclear.

METHODS

The expression of FoxP3 and CD163 was detected by immunohistochemistry in 65 cases of laryngeal squamous cell carcinoma (LSCC). In vitro, the generation of activated Treg (aTreg) cells and M2 macrophages by interactions with their precursor cells were analysed by flow cytometry and ELISA. In vivo, the antitumour effects were assessed by combined targeting aTreg cells and M2 macrophages, and intratumoural immunocytes were analysed by flow cytometry.

RESULTS

In LSCC tissue, accumulation of aTreg cells and M2 macrophages predicted a poor prognosis and were positively associated with each other. In vitro, aTreg cells were induced from CD4⁺CD25^- T cells by cancer cell-activated M2-like macrophages. Consequently, these aTreg cells skewed the differentiation of monocytes towards an M2-like phenotype, thereby forming a positive-feedback loop. Combined targeting aTreg cells and M2 macrophages led to potent antitumour immunity in vivo.

CONCLUSIONS

The positive-feedback loop between aTreg cells and M2 macrophages is essential to maintain or promote immunosuppression in the tumour microenvironment and may be a potential therapeutic target to inhibit tumour progression.

ORONASAL SQUAMOUS CELL CARCINOMAS IN FRANÇOIS' LANGURS (TRACHYPITHECUS FRANCOISI)

Squamous cell carcinomas (SCCs) are common oronasal tumors in nonhuman primates. In this study, 11 cases of oronasal SCC in François' langurs ( Trachypithecus francoisi ) are described. Five initial cases were discovered on review of the North American François' langur studbook, with a potential familial pattern observed. The studbook was used to identify related individuals, and records were requested for review. Six additional cases were documented, and samples from all cases were submitted for microscopic review, as well as polymerase chain reaction (PCR), immunohistochemistry (IHC), and in situ hybridization (ISH), for generic papillomaviruses and PCR for herpesviruses because either virus may cause SCC in humans and other nonhuman primates. Affected langurs commonly presented with facial swelling or ocular discharge but frequently did not have clinical signs, and carcinomas were diagnosed during routine examinations. Carcinomas were located in the oral or nasal cavities affecting the oral mucosa, tongue, hard palate, or oropharynx. Histologically, SCCs comprised anastomosing cords and nests of neoplastic epithelial cells that differentiated synchronously and asynchronously from peripheral basal type cells to central squamous-type cells and were occasionally oriented around accumulations of necrotic cell debris. Nuclear pleomorphism, anisokaryosis, prominent nucleoli, occasional mitoses, and a scirrhous response were common features. All animals tested negative for both viruses, except two langurs that were positive for generic papillomavirus by PCR, but no papillomavirus was detected by either IHC or ISH. In most cases, affected animals died within 5 mo of diagnosis.

TEPAPA: a novel in silico feature learning pipeline for mining prognostic and associative factors from text-based electronic medical records

Vast amounts of clinically relevant text-based variables lie undiscovered and unexploited in electronic medical records (EMR). To exploit this untapped resource, and thus facilitate the discovery of informative covariates from unstructured clinical narratives, we have built a novel computational pipeline termed Text-based Exploratory Pattern Analyser for Prognosticator and Associator discovery (TEPAPA). This pipeline combines semantic-free natural language processing (NLP), regular expression induction, and statistical association testing to identify conserved text patterns associated with outcome variables of clinical interest. When we applied TEPAPA to a cohort of head and neck squamous cell carcinoma patients, plausible concepts known to be correlated with human papilloma virus (HPV) status were identified from the EMR text, including site of primary disease, tumour stage, pathologic characteristics, and treatment modalities. Similarly, correlates of other variables (including gender, nodal status, recurrent disease, smoking and alcohol status) were also reliably recovered. Using highly-associated patterns as covariates, a patient's HPV status was classifiable using a bootstrap analysis with a mean area under the ROC curve of 0.861, suggesting its predictive utility in supporting EMR-based phenotyping tasks. These data support using this integrative approach to efficiently identify disease-associated factors from unstructured EMR narratives, and thus to efficiently generate testable hypotheses.

Peritumoral cuffing by T-cell tumor-infiltrating lymphocytes distinguishes HPV-related oropharyngeal squamous cell carcinoma from oral cavity squamous cell carcinoma

BACKGROUND

It is unclear why human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) has improved clinical behavior compared to HPV-negative HNSCC. We sought to better characterize the immune microenvironment of tongue cancers by examining the CD3 and CD8 TIL pattern in HPV-positive and HPV-negative tumors.

METHODS

Histologic sections from 40 oral tongue and oropharyngeal cases were analyzed (n=21 HPV DNA-positive, n=19 HPV DNA-negative). CD3 and CD8 T-cell immunostaining were performed on whole-slide sections to quantify tumor-infiltrating lymphocyte (TIL) density and assess its morphology.

RESULTS

A subset of cases (HPV-positive) displayed a unique TIL pattern consisting of circumferential peritumoral population T cells, which was absent in the HPV-negative cases. The presence of peritumoral cuffing was strongly predictive of improved recurrence-free survival compared to cases that lacked this morphologic pattern of immune infiltrate. Four HPV-positive cases lacked the pattern, including two cases with disease recurrence.

CONCLUSIONS

For the first time, we show an architectural pattern of immune infiltrate in HNSCC is seen exclusively in HPV-positive patients with improved recurrence-free survival and suggests an organized host immunological response contributes to disease control.

Basaloid Squamous Cell Carcinoma of the Head and Neck: Subclassification into Basal, Ductal, and Mixed Subtypes Based on Comparison of Clinico-pathologic Features and Expression of p53, Cyclin D1, Epidermal Growth Factor Receptor, p16, and Human Papillomavirus

Background

Basaloid squamous cell carcinoma (BSCC) is a rare variant of squamous cell carcinoma with distinct pathologic characteristics. The histogenesis of BSCC is not fully understood, and the cancer has been suggested to originate from a totipotent primitive cell in the basal cell layer of the surface epithelium or in the proximal duct of secretory glands.

Methods

Twenty-six cases of head and neck BSCC from Asan Medical Center, Seoul, Korea, reported during a 14-year-period were subclassified into basal, ductal, and mixed subtypes according to the expression of basal (cytokeratin [CK] 5/6, p63) or ductal markers (CK7, CK8/18). The cases were also subject to immunohistochemical study for CK19, p53, cyclin D1, epidermal growth factor receptor (EGFR), and p16 and to in situ hybridization for human papillomavirus (HPV), and the results were clinico-pathologically compared.

Results

Mixed subtype (12 cases) was the most common, and these cases showed hypopharyngeal predilection, older age, and higher expression of CK19, p53, and EGFR than other subtypes. The basal subtype (nine cases) showed frequent comedo-necrosis and high expression of cyclin D1. The ductal subtype (five cases) showed the lowest expression of p53, cyclin D1, and EGFR. A small number of p16- and/or HPV-positive cases were not restricted to one subtype. BSCC was the cause of death in 19 patients, and the average follow-up period for all patients was 79.5 months. Overall survival among the three subtypes was not significantly different.

Conclusions

The results of this study suggest a heterogeneous pathogenesis of head and neck BSCC. Each subtype showed variable histology and immunoprofiles, although the clinical implication of heterogeneity was not determined in this study.

Laryngeal Dysplasia, Squamous Cell Carcinoma, and Variants

Squamous cell carcinoma (SCC) is a malignant epithelial tumor showing evidence of squamous differentiation. It is the most common malignancy of the larynx, with several variants (verrucous, exophytic or papillary, spindle-cell, basaloid, acantholytic, adenosquamous) recognized, with well-established precursor lesions. Dysplasia is now separated into only low-grade and high-grade categories. Each SCC variant has unique cytomorphologic features and histologic differential diagnoses that are important to consider, as management and outcomes are different.

How phenotype guides management of non-conventional squamous cell carcinomas of the larynx?

Although the majority of laryngeal malignancies are the conventional squamous cell carcinomas (SCC), a wide variety of malignant epithelial tumors can affect the larynx. Current treatment guidelines are designed to guide clinicians in management of conventional laryngeal SCC. Less is known about the biological behavior and responsiveness to therapy and overall outcomes of other malignant epithelial lesions. Because a spectrum of disease biology is represented by these rare phenotypes, an understanding of the basic biology can help direct management to optimize clinical outcome in this group of patients. This review provides a critical analysis of literature relating to the diagnosis, management, and outcome of patients with non-conventional squamous malignant epithelial neoplasms of the larynx. Particular attention is paid to features which are at variance with the conventional SCC and how these impact on management of these rare tumors.

CE: Human Papillomavirus-Related Oral Cancers: The Nurse's Role in Mitigating Stigma and Dispelling Myths

: The prevalence of human papillomavirus (HPV)-related oral cancers has been rising, the cancers occurring in adults at a younger age than HPV-negative oral cancers typically do and in men more often than women. Patients who are diagnosed often don't understand the disease's etiology. Because HPV is sexually transmitted, diagnosis with an HPV-related oral cancer may prompt feelings of shame, embarrassment, and guilt. There are currently three vaccines for HPV. It's essential for nurses to educate patients on HPV transmission and HPV-related oral cancer, thus helping to mitigate the stigma and dispel myths, and to promote vaccination in at-risk populations, including children and young adults.

Bilateral Basaloid Squamous Cell Carcinoma of the Parotid Gland: A Case Report and Review of the Literature

INTRODUCTION

We describe the first known case of bilateral basaloid squamous cell carcinoma of the parotid gland, and we review existing literature.

CASE PRESENTATION

A previously healthy, 70-year-old white man presented with a 2-cm enlarging mass in the tail of the right parotid gland. Magnetic resonance imaging and computed tomography showed ipsilateral pathologic adenopathy. Results of fine-needle aspiration revealed a high-grade malignancy with squamous features. The patient underwent a right total parotidectomy and modified radical neck dissection. Final pathologic findings revealed a basaloid squamous cell carcinoma. Four years after the initial resection, the patient presented with an enlarging left parotid mass. Findings of fine-needle aspiration and imaging were similar to those 4 years earlier. The patient received a left total parotidectomy and modified radical neck dissection. Postoperative radiation therapy was performed after each surgical intervention. He remains disease free at 4-year follow-up after the second mass was resected.

DISCUSSION

Squamous cell carcinoma with basaloid features is a rare and aggressive type of squamous cell carcinoma. To our knowledge, this is the first case report of bilateral parotid basaloid squamous cell carcinoma.

Human Papillomavirus-Associated Neoplasms of the Head and Neck

Human papillomavirus (HPV) is an essential causal factor in a subset of head and neck neoplasms, most notably oropharyngeal squamous cell carcinoma, for which HPV infection has important diagnostic, prognostic, and therapeutic implications. This article summarizes the current understanding of HPV-associated neoplasms of the head and neck, including the recently described carcinoma with adenoid cystic-like features. Salient clinical, gross, and microscopic features are discussed, and the utility of specific ancillary studies is highlighted.

Update from the 4th Edition of the World Health Organization Classification of Head and Neck Tumours: Oropharynx

The changes for oropharyngeal lesions in the 2017 edition of the WHO/IARC Classification of Head and Neck Tumours reference book are dramatic and significant, largely due to the growing impact of high risk human papillomavirus (HPV). The upcoming edition divides tumours of the oral cavity and oropharynx into separate chapters, classifies squamous cell carcinomas (SCC) of the oropharynx on the basis of HPV status, abandons the practice of histologic grading for oropharyngeal SCCs that are HPV positive, recognizes small cell carcinoma of the oropharynx, and combines polymorphous low grade adenocarcinoma and cribriform adenocarcinoma of tongue and minor salivary glands under the single term "polymorphous adenocarcinoma." This review not only calls attention to these changes, but describes the rationale driving these changes and highlights their implications for routine clinical practice.

HPV-Positive Oropharyngeal Cancer Via p16 Immunohistochemistry in Japan

OBJECTIVES

Human papillomavirus (HPV) has emerged as a driving cause of head and neck cancer, but investigations outside the West are limited. A p16 immunohistochemistry is a commonly used biomarker for HPV cancers. We sought to investigate the pathology and rates of HPV head and neck oropharyngeal cancer in Japan via p16 immunohistochemistry at 2 institutions in Japan.

METHODS

Fifty-nine oropharyngeal specimens from 2 university hospitals in Japan were examined for morphology and p16 immunohistochemistry. The rate of p16 positivity was then determined, and the 2 groups were compared for differences in age, smoking history, gender, and stage of presentation and mortality.

RESULTS

The rate of p16 positivity among the oropharyngeal specimens was 29.5%. There were important differences in the pathology compared to morphology usually seen in the US. The patients with p16+ cancer tended to be younger. There was no significant difference in smoking status. Patients with p16+ cancers trended toward better survival.

CONCLUSION

There appears to be a geographical difference in HPV rates of oropharyngeal cancers with persistently lower rates in Asian countries when compared to Western Europe and the US. Conclusions about HPV head and neck squamous cell carcinoma (HNSCC) in Western countries may not be generalizable across the globe at this time.