Lymphoepithelial-like carcinoma of the oropharynx: a morphologic variant of HPV-related head and neck carcinoma. Am J Surg Pathol. 2010;34:800-805. [PMID: 20421782 DOI: 10.1097/pas.0b013e3181d9ba21]

Cyto R-CNN and CytoNuke Dataset: Towards reliable whole-cell segmentation in bright-field histological images

BACKGROUND AND OBJECTIVE

Cell segmentation in bright-field histological slides is a crucial topic in medical image analysis. Having access to accurate segmentation allows researchers to examine the relationship between cellular morphology and clinical observations. Unfortunately, most segmentation methods known today are limited to nuclei and cannot segment the cytoplasm.

METHODS

We present a new network architecture Cyto R-CNN that is able to accurately segment whole cells (with both the nucleus and the cytoplasm) in bright-field images. We also present a new dataset CytoNuke, consisting of multiple thousand manual annotations of head and neck squamous cell carcinoma cells. Utilizing this dataset, we compared the performance of Cyto R-CNN to other popular cell segmentation algorithms, including QuPath's built-in algorithm, StarDist, Cellpose and a multi-scale Attention Deeplabv3+. To evaluate segmentation performance, we calculated AP50, AP75 and measured 17 morphological and staining-related features for all detected cells. We compared these measurements to the gold standard of manual segmentation using the Kolmogorov-Smirnov test.

RESULTS

Cyto R-CNN achieved an AP50 of 58.65% and an AP75 of 11.56% in whole-cell segmentation, outperforming all other methods (QuPath 19.46/0.91%; StarDist 45.33/2.32%; Cellpose 31.85/5.61%, Deeplabv3+ 3.97/1.01%). Cell features derived from Cyto R-CNN showed the best agreement to the gold standard (D¯=0.15) outperforming QuPath (D¯=0.22), StarDist (D¯=0.25), Cellpose (D¯=0.23) and Deeplabv3+ (D¯=0.33).

CONCLUSION

Our newly proposed Cyto R-CNN architecture outperforms current algorithms in whole-cell segmentation while providing more reliable cell measurements than any other model. This could improve digital pathology workflows, potentially leading to improved diagnosis. Moreover, our published dataset can be used to develop further models in the future.

Intraoral salivary lymphoepithelial carcinoma: clinicopathologic and immunophenotypic characterization of 3 cases indicates elevated programmed death-ligand 1 expression

OBJECTIVE

Intraoral salivary lymphoepithelial carcinoma (ISLEC) is a rare malignancy with programmed death-ligand 1 (PD-L1) expression levels that have been greatly understudied. We examined the clinicopathologic and immunophenotypic characteristics, including PD-L1 levels, of 3 cases of ISLEC.

STUDY DESIGN

We searched the archives of 2 oral and maxillofacial pathology laboratories for specimens diagnosed as ISLEC between 1985 and 2022. We collected patient demographic and clinical data. Immunostaining for AE1/AE3, CK7, CD3, CD20, p16, p53, Ki67, and PD-L1 (SP263), as well as Epstein-Barr virus-encoded small RNAs (EBER) in situ hybridization (ISH) were performed.

RESULTS

All 3 cases affected males aged 42 to 84 years (median = 61y) and involved the floor of the mouth, soft palate/uvula, and tongue. The lesions showed diffuse infiltration by non-keratinizing sheets and islands of undifferentiated carcinoma cells with associated dense lymphoplasmacytic inflammation. Immunohistochemically, all tumors showed AE1/AE3 positivity, selective p53 staining, and negativity for CK7 and p16. Ki67 highlighted 20%-80% of lesional cells. The inflammatory infiltrate comprised a mixed population of T and B lymphocytes. EBER ISH was positive in one case. All ISLECs displayed membranous, focal-to-diffuse, PD-L1 staining with tumor proportion score > 95% in two and 40-50% in the third case.

CONCLUSIONS

The clinicopathologic and immunophenotypic characteristics of the cases we examined highlight the rarity of ISLEC and indicate overall high PD-L1 levels in this type of malignancy, rendering patients with ISLEC potential candidates for targeted α-PD-1/PD-L1 immunotherapy.

Nonsebaceous Lymphadenoma of the Salivary Glands: A Potential Overdiagnosis Pitfall

Nonsebaceous lymphadenoma is a rare benign salivary tumor. It is easily misdiagnosed as lymphoepithelial carcinoma, leading to overtreatment. Some patients experience sequelae after undergoing cervical lymph node resection and adjuvant treatment, so it is critical to distinguish these entities. We describe the histopathological and immunohistochemical features of this rare entity in 3 cases and discuss the differential diagnosis and histogenesis. Nonsebaceous lymphadenoma can be distinguished from lymphoepithelial carcinoma by the following histological features: There is a lymph node-like form at low magnification, with prominent proliferating epithelial nests but no destructive growth pattern; variable numbers of tubuloglandular components are always seen in proliferating epithelial nests, which transition to cystically dilated salivary ducts; no lesion necrosis exists; and mitotic figures are absent or rare. No patients experienced recurrence during the 8- to 69-month (mean, 29 months) follow-up.

Clinical characteristics, prognostic factors, and treatment modalities for head and neck lymphoepithelioma-like carcinoma: A real-world study from southern China

BACKGROUND

We aimed to elucidate the clinical characteristics, prognostic factors and optimal treatment modalities of head and neck lymphoepithelioma-like carcinoma (HNLELC).

METHODS

Consecutive patients newly-diagnosed with non-metastatic HNLELC between December 2001 and March 2021 treated with curative intent were retrospectively reviewed.

RESULTS

A total of 288 patients were included, of whom 87 (30.2%) underwent radical surgery alone, 43 (14.9%) underwent definitive radiotherapy with or without concurrent chemotherapy, and 158 (54.9%) underwent surgery followed by postoperative radiotherapy (SRT). Epstein-Barr virus-encoded small RNA (EBER) was positive in 94.8% (239/252) of patients. Cervical node infiltration was seen in 52.8% (152/288) of patients. No significant difference was found in nodal metastasis rate between T1-2 and T3-4 classifications (49.5% vs. 56.5%, p = 0.308). The 3-year overall survival (OS), disease-free survival, locoregional relapse-free survival, and distant metastasis-free survival rates were 89.4%, 78.7%, 89.2%, and 87.7%, respectively. Compared to SRT, surgery alone associated with significant reduced 3-year local (92.8% vs. 96.5%, p = 0.012) and regional relapse-free survival rates (89.3% vs. 96.8%, p = 0.002). Definitive radiotherapy and SRT demonstrated comparable results in all 3-year survival outcomes (all p＞0.05). Multivariate analysis found EBER status was an independent favorable prognostic factor for OS (HR = 0.356, 95% CI: 0.144-0.882, p = 0.026).

CONCLUSION

HNLELC was observed to associate with EBV infection and cervical nodal infiltration. Definitive radiotherapy achieved similar survival outcomes compared to SRT, and may serve as a good substitute for patients unfit or unwilling to undergo surgery.

Lymphoepithelial Subtype of Oral Squamous Cell Carcinoma: Report of an EBV-Negative Case and Literature Review

Lymphoepithelial carcinoma (LEC) of the oral mucosa is a rare histopathologic subtype of squamous cell carcinoma (SCC), which shares morphologic similarities with nasopharyngeal carcinoma (NPC), non-keratinizing undifferentiated subtype. The admixture of neoplastic epithelial tumor cells and a dense lymphoplasmacytic infiltrate makes microscopic diagnosis challenging. LEC etiopathogenesis has been variably associated with Epstein–Barr virus (EBV) infection, depending on the specific anatomic location and racial predilection, with a higher incidence in endemic populations. Although described in several subsites of the head and neck region, including the major salivary glands, the oral mucosa is considered an infrequent location for LEC development, deriving either from minor salivary glands (MSGs) or the surface epithelium. Herein, we report a rare case of an EBV-negative LEC arising from the oral surface epithelium, presenting as gingival swelling, and review the pertinent English-language literature, which revealed only 26 previously reported oral LECs. Our case is only the fourth oral LEC originating from the surface epithelium and the first one to affect the gingiva.

MDM2 is a useful diagnostic marker for nasopharyngeal carcinoma

BACKGROUND

The MDM2 gene appears to be involved in the development of nasopharyngeal carcinoma. The aim of this study was to examine MDM2 expression in a series of nasopharyngeal carcinoma biopsies to explore its potential diagnostic significance.

METHODS

The study cohort consisted of 26 nasopharyngeal carcinomas, including 22 EBV positive non-keratinizing squamous cell carcinomas (NKSCC), 1 EBV negative NKSCC and 3 EBV negative keratinizing SCC. For comparison, we selected 48 oropharyngeal carcinomas, including 17 HPV positive SCC (14 non-keratinizing and 3 keratinizing) and 31 HPV negative SCCs (28 keratinizing and 3 non-keratinizing). In addition, we examined MDM2 expression in a group of 26 cervical lymph node metastases, including 5 with EBV positive nasopharyngeal NKSCC and 21 from oropharyngeal carcinoma (18 non keratinizing HPV positive, 1 keratinizing HPV positive, 1 keratinizing HPV negative and 1 non-keratinizing HPV negative). Finally, 2 bone metastases from EBV positive nasopharyngeal NKSCC were also included. A tissue microarray was constructed from formalin-fixed paraffin embedded tumor tissue specimens. Sections were immunostained for MDM2 and in situ hybridization for EBER and CISH analysis for the MDM2 gene were also conducted in all cases.

RESULTS

Overall, MDM2 positivity was detected in 28 of 102 SCCs (27.2 %). MDM2 positivity was significantly more frequent in EBV positive NKSCC (80 %) than in oropharyngeal HPV positive NKSCC (6.1 %) and keratinizing SCCs (9.4 %) (p < 0.001, Pearson chi square). Considering only the primary tumors, 86.4 % of the nasopharyngeal carcinomas were positive, versus 13.5 % of the oropharyngeal carcinomas (p < 0.001, Pearson chi square). Considering the lymph node metastases, 3 of 5 EBV positive carcinomas with nasopharyngeal primary were positive, whereas only one of the HPV positive carcinomas was positive. Finally, both the bone metastases from EBV positive nasopharyngeal carcinoma were positive for MDM2. No amplification of the MDM2 gene was identified by in situ hybridization analysis.

CONCLUSIONS

Our data indicate that MDM2 could be a valuable diagnostic marker to support the diagnosis of nasopharyngeal EBV positive NKSCC.

Update from the 5th Edition of the World Health Organization Classification of Head and Neck Tumors: The Neck and Lymph Nodes, Metastasis, and Melanocytic Tumors

The changes made in the fifth edition of the WHO Classification of Head and Neck Tumors demonstrate the recent diagnostic, histopathological, and molecular advances in the field, and this updated information will hopefully lead to improved and standardized tumor subtyping. This review summarizes the changes related tumors and tumor-like lesions of the neck and lymph nodes (Chapter 11), metastasis to the head and neck region (Chapter 15), and melanocytic tumors (Chapter 10).

HPV-associated oropharyngeal cancer: epidemiology, molecular biology and clinical management

Human papillomavirus (HPV)-positive (HPV⁺) oropharyngeal squamous cell carcinoma (OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the UICC/AJCC staging system separates HPV⁺ OPSCC from its HPV-negative (HPV⁻) counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment de-intensification as a means to improve quality of life while maintaining acceptable survival outcomes. In addition, owing to the distinct biology of HPV⁺ OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage owing to a lack of symptoms in the early stages; therefore, a need exists to identify and validate possible diagnostic biomarkers to aid in earlier detection. In this Review, we provide a summary of the epidemiology, molecular biology and clinical management of HPV⁺ OPSCC in an effort to highlight important advances in the field. Ultimately, a need exists for improved understanding of the molecular basis and clinical course of this disease to guide efforts towards early detection and precision care, and to improve patient outcomes.

The incidence of human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) is increasing rapidly in most developed countries. In this Review, the authors provide an overview of the epidemiology, molecular biology and treatment of HPV-positive OPSCC, including discussions of the role of treatment de-escalation and emerging novel therapies.

The incidence of human papillomavirus-associated oropharyngeal cancer (HPV⁺ OPSCC) is expected to continue to rise over the coming decades until the benefits of gender-neutral prophylactic HPV vaccination begin to become manifest.

The incidence of HPV⁺ OPSCC appears to be highest in high-income countries, although more epidemiological data are needed from low- and middle-income countries, in which HPV vaccination coverage remains low.

The substantially better prognosis of patients with HPV⁺ OPSCC compared to those with HPV^– OPSCC has been recognized in the American Joint Committee on Cancer TNM8 staging guidelines, which recommend stratification by HPV status to improve staging.

The molecular biology and genomic features of HPV⁺ OPSCC are similar to those of other HPV-associated malignancies, with HPV oncogenes (E6 and E7) acting as key drivers of pathogenesis.

Treatment de-intensification is being pursued in clinical trials, although identifying the ~15% of patients with HPV⁺ OPSCC who have recurrent disease, and who therefore require more intensive treatment, remains a key challenge.

Demographics, clinical features, and prognosis of rare lymphoepithelioma-like carcinoma across different anatomic sites

Background

Lymphoepithelioma-like carcinoma (LELC) is an unusual histological malignancy type. Due to the rarity of this disease, we used the Surveillance, Epidemiology, and End Results (SEER) database to investigate comprehensively and systematically the prognosis factor of LELC.

Methods

We identified 2079 patients diagnosed with LELC during 1973–2015 from the SEER database. LELC was classified according to the tumor site. We analyzed the clinical characteristics and estimated the hazard ratio (HR) of overall mortality of LELC at each site.

Results

The nasopharynx was the most frequent site where LELC (58%) occurred. A large percentage of nasopharyngeal and pulmonary LELC patients were of Asian descent (44.5 and 32.56%, respectively). Furthermore, the majority of LELC patients were rather young when diagnosed. However, urinary bladder LELC and digestive system LELC (mean age: 69.03 and 68.05 years, respectively) were mainly to be found in older patients. Then according to Kaplan–Meier survival analysis, we found that patients with pulmonary LELC had worse survival. After adjusting for clinical tumor characteristics, pulmonary LELC patients were at increased risk of overall mortality compared with nasopharyngeal LELC either at the localized stage (HR 3.12, 95% confidence interval [CI], 1.55–6.26. P < 0.01) or at the regional stage (HR 1.72, 95% CI 1.03–2.88 P = 0.04).

Conclusions

In conclusion, we found that urinary bladder and digestive system LELCs mainly were diagnosed in old people and different from other LELCs. Pulmonary LELC patients might have a bad prognosis. The origination site may represent a predictive factor for determining survival in patients with LELC.

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.

Lymphoepithelial carcinoma of larynx and hypopharynx: a systematic review and pooled analysis

PURPOSE

To define the oncologic outcomes and the prognostic factors of laryngeal and hypopharyngeal lymphoepithelial carcinoma (LEC).

METHODS

A systematic review and individual patient data analysis were performed according to the PRISMA guidelines. A total of 41 patients (males: 37; mean age: 63.1, standard deviation: 10.0) were included.

RESULTS

The median follow-up time was 36.0 months (interquartile range, IQR: 11.5-73.5), while the median overall survival (OS) time was 96 months (IQR: 39.0-120.0). Estimated disease-specific survival (DSS) rates (95% Confidence Interval, CI; number still at risk) at 1, 3, and 5 years were 94.4% (79.5-98.6; 31), 82.7% (62.7-92.5; 21), and 78.1% (56.8-89.7; 13), respectively. Estimated disease-free survival (DFS) rates (95% CI; number still at risk) at 1, 3, and 5 years were 92.1% (77.4-97.4; 31), 74.9% (55.6-86.8; 21), and 66.6% (46.1-80.8; 13), respectively. Patients undergoing primary surgery had a reduced chance of death from cancer than patients receiving primary radiotherapy (5-year DSS 85.6 vs. 56.2%; p = 0.04), while EBV positivity tend to be a negative prognostic factor (5-year DSS 100 vs. 66.7%; p = 0.05).

CONCLUSIONS

Laryngeal and hypopharyngeal LEC is a rare disease with favorable survival. Further prospective multicenter studies are needed to make a reliable statement on prognosis and outcome, stratifying patients for different therapy regimens and tumor stages.

Lymphoepithelial carcinoma of the parotid gland: a unique example showing p16 immunoreactivity

Lymphoepithelial carcinoma (LEC) shows characteristic histology of nesting growth of tumor cells with unclear differentiation against the lymphoid stroma background. Although rare in salivary glands, it has previously been recognized as a type of undifferentiated carcinoma but is currently clearly defined as an independent disease separate from undifferentiated carcinoma. We report a case of LEC that developed in the parotid gland and was immunohistochemically positive for p16, which suggested the causative involvement of human papillomavirus (HPV). The patient was a 38-year-old Japanese male aware of mass formation in the left parotid area for 8 years. Parotidectomy was performed and there have been no signs of recurrence or metastasis for 18 month post-operation. The tumor was histologically typical except for Epstein-Barr virus (EBV)-encoded small RNA (EBER)-negative in situ hybridization (ISH), but p16-positivity by immunohistochemistry, and also frequent contact with extended and expanded pre-existing ductal structures. Although usually strongly associated with EBV infection, the tumor could be regarded to have eventually reached completion as a LEC lesion associated with HPV infection possibly through the pathway shared with squamous cell carcinoma. EBER-ISH remains the most promising index for confirming diagnosis of LEC, but EBV-negative result alone should not prevent diagnosis of LEC.

Oropharyngeal Squamous Cell Carcinoma Morphology and Subtypes by Human Papillomavirus Type and by 16 Lineages and Sublineages

Oropharyngeal squamous cell carcinoma (SCC) is increasing in incidence and, in Western countries, strongly associated with transcriptionally-active high-risk human papillomavirus (HPV). Within HPV-positive tumors, there is wide morphologic diversity with numerous histologic subtypes of SCC. There are also variable degrees of keratinization, anaplasia, stromal fibrosis, and maturing squamous differentiation. Unlike in the uterine cervix, where associations between HPV types and lineages/sublineages within types have been investigated with some clear correlations identified, little to no data exists for oropharyngeal SCC. In this study, for a large cohort of oropharyngeal SCC patients, we performed RTPCR for high-risk HPV. For the HPV positive patients, we sequenced the DNA of the entire HPV16 genome and determined lineages and sublineages, correlating HPV status, genotype, and HPV16 lineages/sublineages with SCC subtype and various histologic features. Of the 259 patients, 224 (86.5%) were high-risk HPV positive, of which 210/224 (93.8%) were HPV type 16 and 6/224 (2.7%) HPV type 33. Of the four HPV16 lineages, A was the most frequent (192/214 or 89.8%) and of the HPV16 A sublineages, A1 was the most frequent (112/210 or 53.3%). Patients with HPV negative tumors were more often keratinizing vs other types (23/35 or 65.7%) and thus more likely to have more maturing squamous differentiation and stromal desmoplasia. There was no significant correlation between HPV type (16 versus other), between HPV16 lineage (A versus others), or HPV16 A sublineages (A1 or A2 versus others) and morphologic type of SCC nor the various morphologic features of anaplasia/multinucleation, degree of keratinization, nor amount of stromal desmoplasia. In summary, in our cohort, there was no correlation between the type of HPV, the HPV 16 lineage or sublineage, and any of the histologic features or morphologic SCC subtypes.

Lymphoepithelial Carcinoma of Salivary Glands

Lymphoepithelial carcinoma of salivary glands (LECSG) is an uncommon neoplasm. This article summarizes the findings of 438 cases in a review of the literature. Concurrent lymphoepithelial lesions may suggest a primary tumor. The tumor shows a nonkeratinizing carcinoma intimately associated with a rich lymphohistiocytic infiltrate, destroying adjacent salivary gland tissue. Irrespective of race or ethnicity, the tumors usually express Epstein-Barr virus, with Epstein-Barr virus encoded small RNA (EBER) and/or latent membrane protein-1 (LMP-1), although a subset does not. There is an overall good prognosis of about 80% at 5 years.

Clinicopathological characteristics and prognostic analysis of lymphoepithelial carcinoma of salivary gland: a population-based study

Background

The purpose of this study was to elucidate the clinicopathological characteristics of patients with lymphoepithelial carcinoma of salivary gland (LEC-SG) and determine the factors associated with survival.

Methods

A total of 179 LEC-SG patients from the Surveillance, Epidemiology, and End Results (SEER) database between 1975 to 2016 were included. The clinicopathological characteristics and overall survival of LEC-SG patients were described, and the features affecting prognosis were further determined using Kaplan-Meier Curves and Cox survival analysis.

Results

The median overall survival of LEC-SG patients was 206 months, and the 1-, 5-, 10- and 20-year survival rates were 91.0%, 80.2%, 66.4%, and 37.6%, respectively. The prognoses were significantly associated with age, ethnicity, marital status, tumor invasion, as well as lymph node metastases [P<0.01 for all). Surgical resection could significantly improve the prognosis of this disease (median overall survival (mOS): 219 vs. 68 months, P<0.01]. Postoperative radiotherapy could improve long-term survival and decrease the risk of death among patients who survive exceed 10-year after surgery. The Cox regression analysis showed that old age (>60 years) and lymph node metastases were independently associated with poor survival (P<0.05 for both). Conversely, the use of surgery was an independent favorable prognostic factor [hazard ratio (HR) 0.29, 95% CI: 0.13-0.66].

Conclusions

LEC-SG patients had a favorable prognosis with a mOS of 206 months. Old age, lymph node metastases, the use of surgery were independently associated with survival of LEC-SG patients.

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.

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.

Lymphoepithelial Carcinoma of Larynx and Hypopharynx: A Rare Clinicopathological Entity

(1) Background: Lymphoepithelial carcinoma of the hypopharynx and larynx is a rare tumor with fewer than 50 cases in the published literature. We present a literature review to discuss the clinical findings, viral or genetic associations, diagnostic challenges, histopathological findings and therapeutic aspects of the disease. (2) Methods: A comprehensive literature review was performed through MEDLINE/PubMed from 1968 to 2018. We identified 21 studies comprising 46 patients. Data on all the clinicopathological features, diagnostic modalities, treatment options and viral or genetic etiology were extracted and analyzed using SPSS. (3) Results: The mean age of presentation was 64 years (range 40–82 years) and mostly involved males. The supraglottis and pyriform sinus were the most commonly involved sub-sites, with surgery as the preferred treatment modality. The presence of the Epstein–Barr virus possibly directs a viral etiology. The incidence of cervical and distant metastasis was 54% and 21%, respectively. The median survival time was 30 months. (4) Conclusions: Lymphoepithelial carcinoma of the hypopharynx is an aggressive tumor with a strong predilection for regional and distant metastasis. Surgery, in combination with adjuvant therapy, provides promising results. Immunohistochemistry helps in differentiating LEC from other pathologies.

Lymphoepithelial Carcinoma of Salivary Gland EBV-association in Endemic versus Non-Endemic Patients: A Report of 16 Cases

Lymphoepithelial carcinoma of salivary glands (LECSG) are rare neoplasms, reported in endemic populations (southeastern Chinese) with a strong Epstein-Barr virus (EBV) association. A retrospective series comparing EBV status within an ethnically diverse population (endemic vs. non-endemic patients) has not been reported. Sixteen LECSG were equally distributed between males (n = 8) and females (n = 8) with a median age of 54 years (range 18 to 85 years) at initial diagnosis. Ten patients were white, 4 Asian, and 2 black. The patients typically presented with swelling or mass for an average of 11.6 months. Tumors affected only major salivary glands: parotid (n = 13); submandibular (n = 3). Tumors were an average of 2.9 cm (range 1.5 to 5.8 cm). Nine of 16 (56%) patients had cervical lymph node metastases at presentation. No patients had nasopharyngeal or oropharyngeal tumors. Microscopically, the tumors were widely infiltrative, characterized by large polygonal to spindled cells arranged in a syncytial, lattice-like network in a background of lymphoplasmacytic cells. The neoplastic cells showed an open-vesicular nuclear chromatin to a more basaloid-morphology, the latter showing hyperchromatic nuclei and less cytoplasm, while nearly all of the cases had associated lymphoepithelial lesions/sialadenitis. By in situ hybridization, 8 of 16 cases had a strong, diffuse EBER expression (4 of 4 Asians; 4 of 12 non-Asians), while with immunohistochemistry all cases tested were pan-cytokeratin, CK5/6 and p63 reactive; none of the cases tested were p16 reactive. All patients were managed with wide or radical excision, 4 with concurrent chemoradiation, and 6 with radiation alone. Distant metastasis (lung, brain, and bone) developed in 2 patients. Overall follow-up (mean 3.8 years) revealed 12 patients alive and 2 dead, none with evidence of disease (mean 4.3 years); one white male alive with disease at 1.9 years, and one Asian female dead of disease at 4.2 years; both of these latter patients had Group IV stage disease. High stage (Group IV) patients had a shorter mean survival than lower stage patients: 3.1 versus 4.8 years, respectively. In conclusion, LECSG are uncommon primary neoplasms. Concurrent lymphoepithelial lesions may help suggest a primary tumor. The tumors, irrespective of race or ethnicity, may express EBER. There is an overall good survival, perhaps better for EBV-negative patients and for those with lower stage disease.

High-risk human papillomavirus-mediated adenocarcinoma of palatine tonsil

We describe the case of a human papillomavirus-mediated adenocarcinoma of palatine tonsil in a 51-year-old male. Histologically, the tumor exhibited a predominantly cribriform and tubular (glandular) growth of cuboidal and columnar cells with moderate amount of pale eosinophilic cytoplasm and oval or spindled nuclei with finely dispersed or coarse chromatin and small to medium-sized nucleoli. Foci of nuclear anaplasia and multinucleation, numerous mitotic figures, and necrosis (individual-cell and confluent) were seen. No squamous differentiation was identified. The tumor cells showed strong expression of CK7, p16 and HPV E6/E7 mRNA transcripts, and were negative for p40, CK5/6, AR, synaptophysin and chromogranin. Next generation sequencing showed 3 variants of unknown significance: FGF3 p.(R44fs); NF1 p.(S749 L) and POLE p. (S1506 L) with variant allele frequencies of 37 %; 20 %, and 17 % respectively. Chromosomal microarray analysis using single nucleotide polymorphism microarray (OncoScan) assay showed whole chromosomal gains of chromosomes 8 and 19, whole chromosomal losses of chromosomes 2 and 16, as well as segmental gains of chromosomes 3q25.31q29 (encompassing the PIK3CA gene), 17q21.31q25.3, 20p13q13.33, Xq28, and segmental losses of chromosomes 1q32.2, 6p25.1p21.1, 11q23.1q24.1, 12p11.22, 12p11.22, 14q24.1q32.33, 17p13.3q21.31 (encompassing the TP53 and NF1 genes). The results highlight the need to consider HPV testing in non-squamous cell carcinomas of the oropharynx.

Clinico-pathological peculiarities of human papilloma virus driven head and neck squamous cell carcinoma: A comprehensive update

AIMS

The current article provides a detailed account of the current understanding of molecular and clinico-pathological aspects of Human papilloma virus (HPV) driven head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

The literature review included most of the landmark trials and clinical studies related to the HPV driven HNSCC.

KEY FINDINGS

HPV positive HNSCC differ distinctly from HPV negative tobacco-related HNSCC, especially in oropharyngeal region. Therefore, the American joint committee on cancer`s latest manual for classification and staging of cancer suggests a separate staging system for HPV positive oropharyngeal cancers. Despite the younger patients being affected and the high propensity for cervical metastasis, the HPV positive oropharyngeal cancers respond much better to the treatment. The association with wild type TP53 and low EGFR expression confers the favorable prognosis in HPV driven HNSCC. Since the association is not universal, we suggest checking for p53 and EGFR expression status before considering de-intensification of therapy. In addition, the presence of matted lymph nodes and five or more nodes could mean relatively poorer prognosis, and are not suitable for de-intensification of therapy. The same is also true probably with higher T stage and co-existing tobacco use. The methods for the detection of p16, HPV DNA, HPV E6/E7 mRNA, anti-E6/E7 antibodies, in tissue, in serum and in saliva of patients, along with their clinical implications are also discussed.

SIGNIFICANCE

This article provides latest developments on the HPV driven HNSCC. 'Diagnosis of transcriptionally active HPV infection,' 'Modalities for surveillance,' 'Implication of de-escalation of therapy' are some of the critical issues that could serve the medical, the research as well as the patient communities.

Human papilloma virus related squamous cell carcinomas of the head and neck: diagnosis, clinical implications and detection of HPV

High-risk human papillomavirus (HPV) positive squamous cell carcinoma (SCC) of the head and neck is reported most commonly in the oropharynx but can also uncommonly be found in other sites such as the anterior oral cavity and sinonasal tract. While HPV positive oropharyngeal squamous cell carcinoma (HPV-OPSCC) has been shown to have a more favourable prognosis than conventional smoking- and alcohol-related anterior oral cavity squamous cell carcinoma (OSCC), HPV positive SCC arising elsewhere in the head and neck region does not carry the same favourable prognosis. HPV-OPSCC often tends to present with large cystic metastases in the cervical lymph nodes, with a clinically and radiologically occult primary. Correct diagnosis of the initial biopsy/cytology specimen is critical for directing further investigations and management. In recognition of its distinct biological behaviour, the 8th edition of the American Joint Commission on Cancer (AJCC 8) has proposed a separate clinical and pathological staging system for HPV-OPSCC compared to that for a conventional primary OSCC or neck metastasis of similar size. The new AJCC staging does not apply to other HPV positive SCC of the head and neck. This review examines the current biology of HPV positive SCC, focusing on HPV-OPSCC. The value and pitfalls of current detection methods of HPV are discussed with an emphasis on the role of the pathologist in the diagnosis and management of HPV positive SCC of the head and neck.

Oropharyngeal Squamous Cell Carcinoma in 390 Patients: Analysis of Clinical and Histological Criteria Which Significantly Impact Outcome

This study evaluates the prognostic impact of several factors in oropharyngeal squamous cell carcinoma (OPSCC), controlling for human papillomavirus (HPV)-associated tumors and stage (American Joint Committee on Cancer 8th edition). All patients in Southern California Permanente Medical Group diagnosed with OPSCC between 2006 and 2012 tested for p16 immunohistochemistry were included. Review of all pathology materials was combined with central p16 testing. Multivariable analyses were performed. The cohort of 390 patients included 342 p16-positive and 48 p16-negative tumors. For all-comers, on univariate analysis, the following factors, when present, were associated with improved patient survival: p16-positive tumor (n = 324, p < 0.001); crypt versus surface tumor location (n = 312, p = 0.004); nonkeratinizing type (n = 309, p < 0.0001); nonkeratinizing with maturation type (n = 37, p < 0.0001); basaloid pattern (n = 284, p = 0.005); and a broad, pushing border of infiltration (n = 282, p = 0.004). Inferior survival outcomes were observed with: age ≥ 55 years (p < 0.0001); ≥ 10 pack-year smoking history (n = 183, p = 0.003); increasing tumor stage (p < 0.0001); overt radiographic extranodal extension (ORENE) (n = 58, p < 0.0001); low level IV/Vb lymph node involvement (n = 45, p = 0.0002); a jagged pattern of infiltration (n = 76, p = 0.0004); tumor ulceration (n = 76, p = 0.0004); absent lymphocytic infiltrate (p < 0.0001); and concurrent dysplasia (n = 125, p = 0.009). On multivariable analysis, accounting for patient age, smoking history ≥ 10 pack-years, and TNM stage, for patients with p16-positive disease, advanced TNM stage (p = 0.007), the presence of ORENE (p = 0.0002), and low-neck lymphadenopathy (p = 0.0001) were independent negative prognostic factors for disease free survival (DFS). Older age (p < 0.0001), smoking history ≥ 10 pack-years (p = 0.02), advanced TNM stage (p = 0.0002), ORENE (p = 0.004), and low-neck lymphadenopathy (p = 0.002) were independent negative prognostic factors for OS. Among patients with p16-positive OPSCC, older age, smoking history, advanced stage, ORENE, and low-neck lymphadenopathy were significant negative prognostic factors for DFS and/or OS. Further refinement of staging to incorporate additional lymph node findings may be warranted.

The pathology of oral cancer

The term 'oral cancer' describes a range of malignancies that may arise in and around the oral cavity. Over 90% of such lesions are squamous cell carcinomas, but even these may be divided into different entities based on site, aetiology and prognosis. In particular, squamous carcinomas in the oral cavity (oral cancer) should be regarded as a different disease to carcinomas arising in the oropharynx. Oropharyngeal cancer is associated with infection by human papillomavirus (HPV) and shows different clinical and histological features. This short review summarises the pathology of oral and oropharyngeal cancer, and describes some of the main prognostic factors that pathologists use to assist clinicians in planning appropriate management.

Human papillomavirus in laryngeal and hypopharyngeal lymphoepithelial carcinoma

The involvement of human papillomavirus (HPV) in laryngeal and hypopharyngeal lymphoepithelial carcinoma was investigated in a series of ten cases (seven laryngeal and three hypopharyngeal), retrieved from the files of three tertiary hospitals in the 2000-2017 period, through polymerase chain reaction with SPF10 primers and INNO-LiPA HPV Genotyping Extra II (Innogenetics). Epstein-Barr virus (EBV) was tested in all cases with in situ hybridization INFORM EBER Probe (Ventana Medical Systems). p16 and p53 expression were immunohistochemically analyzed. Calculated annual incidence was 0.013/100,000, and prevalence was 0.2% of laryngeal and hypopharyngeal carcinomas. All cases were EBV negative. HPV was detected in five cases, three of which also overexpressed p16. HPV16 was detected in four cases, and HPV58 in one case. Five cases were HPV negative, only one of these five overexpressed p16. No recurrence was observed in nine cases during follow-up. The 5-year disease-specific-survival rate was 100%. Mean overall survival was 87 months. Lymphoepithelial carcinoma of the larynx and hypopharynx are not related to EBV. Simultaneous HPV+/p16+ is consistent with HPV causation in a fraction of laryngeal and hypopharyngeal lymphoepithelial carcinomas.

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.

Primary Tonsillar Epithelioid Follicular Dendritic Cell Sarcoma: Report of a Rare Case Mimicking Undifferentiated Carcinoma and a Brief Review of the Literature

We present a 52 years old male with a left tonsillar follicular dendritic cell sarcoma with prominent epithelioid features that on light microscopical examination bore a striking resemblance to a lymphoepithelial or undifferentiated carcinoma. The tumor was immunohistochemically positive for CD21 and CD35 and negative for cytokeratins. Two distinct histopathological features (both present in our case) that may serve as clues to the correct diagnosis on light microscopical examination were formation of ectatic pseudovascular spaces lined by malignant cells and the presence of non-neoplastic multinucleated giant cells. Familiarity with the above-mentioned morphological clues, and awareness that this tumour may occur in anatomical sites outside the lymph node, are essential for accurate diagnosis.

Clinical Utility of In Situ Hybridization Assays in Head and Neck Neoplasms

Head and neck pathology present a unique set of challenges including the morphological diversity of the neoplasms and presentation of metastases of unknown primary origin. The detection of human papillomavirus and Epstein-Barr virus associated with squamous cell carcinoma and newer entities like HPV-related carcinoma with adenoid cystic like features have critical prognostic and management implications. In salivary gland neoplasms, differential diagnoses can be broad and include non-neoplastic conditions as well as benign and malignant neoplasms. The detection of specific gene rearrangements can be immensely helpful in reaching the diagnosis in pleomorphic adenoma, mucoepidermoid carcinoma, secretory carcinoma, hyalinizing clear cell carcinoma and adenoid cystic carcinoma. Furthermore, molecular techniques are essential in diagnosis of small round blue cell neoplasms and spindle cell neoplasms including Ewing sarcoma, rhabdomyosarcoma, synovial sarcoma, biphenotypic sinonasal sarcoma, dermatofibrosarcoma protuberans, nodular fasciitis and inflammatory myofibroblastic tumor. The detection of genetic rearrangements is also important in lymphomas particularly in identifying 'double-hit' and 'triple-hit' lymphomas in diffuse large B cell lymphoma. This article reviews the use of in situ hybridization in the diagnosis of these neoplasms.

Human papillomavirus associated head and neck squamous cell carcinoma: Controversies and new concepts

High-risk human papillomavirus (HR-HPV) is a causative agent for an increasing subset of oropharyngeal squamous cell carcinoma. HPV 16 accounts for 90% of cases. The chance for malignant transformation due to infection with high-risk HPV is proportional to the expression of the viral oncogene products E6 and E7, which inactivate p53 and retinoblastoma (Rb) tumor suppressor functions. P16 is a surrogate marker of HPV associated HNSCC and 2+/3+ expression in more than 75% cells is diagnostic. Molecular demonstration of integrated virus by in situ hybridization is specific but has low sensitivity. HPV associated oropharyngeal carcinomas classically arise in the tonsillar crypts and commonly have basaloid morphology with a prominent lymphocytic repsonse and minimal despmoplastic reaction. In situ vs invasive carcinomas may be difficult to distinguish in histology. The HPV postitivity overrides traditional prognostic indicators such as tumour grade and histological subtype. Small cell morphology carries a poorer prognosis as does marked tumour anaplasia and multinucleation. Lymph node metastasis is extensive and frequently cystic however extranodal extension, laterality or nodal sizes do not carry prognostic implications as in conventional OSCC and OPSCC. Stage IV is reserved for distant metastasis. HPV-16-positive patients had significantly reduced overall and disease-specific mortality rates and an improved 3-year overall survival (OS) and disease-free survival (DFS) compared to patients with HPV negative tumors. Surgical treatment is the main option for primary and secondary HNSCC. Targeted therapies including drugs targeting EGFR and PIK3CA and have shown some promising results. HPV pathway expressing tumors are less aggressive and may receive adequate curative intent therapy from a reduced radiation or chemotherapy dose revision. OSCC however fails to show a distinct difference between HPV associated and tobaccco associated cancer and prognostic differences do not clearly exist.

Squamous and Neuroendocrine Specific Immunohistochemical Markers in Head and Neck Squamous Cell Carcinoma: A Tissue Microarray Study

The performance characteristics of neuroendocrine-specific and squamous-specific immunohistochemical markers in head and neck squamous cell carcinomas (SCC), in particular in oropharyngeal tumors in this era of human papillomavirus (HPV)-induced cases, are not well-established. The differential diagnosis for poorly differentiated SCCs, for nonkeratinizing oropharyngeal SCCs, and for other specific SCC variants such as basaloid SCC and undifferentiated (or lymphoepithelial-like) carcinomas includes neuroendocrine carcinomas. Given that neuroendocrine carcinomas of the head and neck are aggressive regardless of HPV status, separating them from SCC is critically important. In this study, we examined the neuroendocrine markers CD56, synaptophysin, and chromogranin-A along with the squamous markers p40 and cytokeratin 5/6 in a large tissue microarray cohort of oral, oropharyngeal, laryngeal, and hypopharyngeal SCCs with known HPV results by RNA in situ hybridization for the oropharyngeal tumors. Results were stratified by site and specific SCC variant. The neuroendocrine stains were rarely expressed in SCC (<1% overall) with CD56 the least, and chromogranin-A the most, specific markers. Further, p40 and cytokeratin 5/6 were very consistently expressed in all head and neck SCC (>98% overall), including very strong, consistent staining in oropharyngeal HPV-related nonkeratinizing SCC. Undifferentiated (or lymphoepithelial-like) carcinomas of the oropharynx are more frequently p40 or cytokeratin 5/6 negative or show only weak or focal expression. In summary, markers of neuroendocrine and squamous differentiation show very high specificity and sensitivity, respectively, across the different types of head and neck SCC.

NUT Midline Carcinoma of the Sublingual Gland: Clinical Presentation and Review

NUT midline carcinoma (NMC) is a rare and aggressive disease encountered in the midline of the head and neck or mediastinum. Due to its sparse incidence and subtle pathologic features, we aim to increase knowledge and awareness for this pathologic entity. We present an exemplary case of a young, healthy male presenting with oral cavity pain and cervical lymphadenopathy. This patient was initially diagnosed with an unspecified, highly aggressive sublingual gland malignancy and underwent locoregional resection with free flap reconstruction however suffered a rapid local recurrence and widely extensive metastasis within just 1 month. After rigorous analysis, final pathologic diagnosis revealed a poorly differentiated carcinoma with evidence of squamous differentiation that eventually, post-mortem tested positive for NMC. Only one prior case of sublingual gland NMC has been previously reported as we discuss the literature regarding all sublingual gland malignancies as well as the pathologic features and treatment options for NMC. We recommend consideration of testing for the NUT proto-oncogene at the time of biopsy in the clinical setting of a poorly differentiated midline carcinoma, especially with squamous differentiation, of the head or neck in order to identify patients for clinical trial enrollment and appropriately counsel on the poor clinical prognosis. Improving clinician awareness is critical to increase diagnostic accuracy and need to study prospective treatment outcomes as the first step toward improving management of this difficult disease.

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.

Virus-associated neoplasms of the nasopharynx and sinonasal tract: diagnostic problems

A significant fraction of nasopharyngeal and sinonasal tumors are associated with Epstein-Barr virus (EBV) or human papillomavirus (HPV). Nasopharyngeal carcinoma (NPC) and extranodal NK/T-cell lymphoma harbor EBV in practically all cases, although a small proportion of cases of the former harbor HPV. Sinonasal inverted papillomas harbor HPV in about 25% of cases. Sinonasal squamous cell carcinomas harbor transcriptionally active HPV in about 20% of cases, and limited data suggest that this subset has a better prognosis than the HPV-negative subset. This review addresses the diagnostic issues of the EBV-associated tumors. Difficulties in diagnosis of NPC may be encountered when there are prominent crush artifacts, many admixed lymphoid cells masking the neoplastic cells, or numerous interspersed granulomas, whereas benign cellular components (epithelial crypts and germinal centers) and reactive lymphoid hyperplasia can potentially be mistaken for NPC. Immunostaining for pan-cytokeratin and/or in situ hybridization for EBER can help in confirming or refuting a diagnosis of NPC. The main diagnostic problem of extranodal NK/T-cell lymphoma is recognition of the neoplastic nature of those examples predominated by small cells or showing a mixture of cells. The identification of a destructive infiltrate (dense expansile infiltrate; angiocentric growth) and definite cytologic atypia (clear cells; many medium-sized cells) would favor a diagnosis of lymphoma, which can be supported by immunohistochemistry (most commonly CD3+, CD5-, CD56+) and in situ hybridization for EBER. In conclusion, among nasopharyngeal and sinonasal neoplasms, demonstration of EBV may aid in diagnosis, particularly NPC and extranodal NK/T-cell lymphoma. Demonstration of HPV does not have a role yet in diagnosis, although this may change in the future.

Morphologic diversity in human papillomavirus-related oropharyngeal squamous cell carcinoma: Catch Me If You Can!

As the human papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma epidemic has developed in the past several decades, it has become clear that these tumors have a wide variety of morphologic tumor types and features. For the practicing pathologist, it is critical to have a working knowledge about these in order to make the correct diagnosis, not to confuse them with other lesions, and to counsel clinicians and patients on their significance (or lack of significance) for treatment and outcomes. In particular, there are a number of pitfalls and peculiarities regarding HPV-related tumors and their nodal metastases that can easily result in misclassification and confusion. This article will discuss the various morphologic types and features of HPV-related oropharyngeal carcinomas, specific differential diagnoses when challenging, and, if established, the clinical significance of each finding.

Epstein-Barr Virus in Nasopharyngeal Carcinoma of Guatemalan and Brazilian Patients

BACKGROUND

Nasopharyngeal carcinoma (NPC) is highly associated with Epstein-Barr virus (EBV), particularly the undifferentiated nonkeratinizing subtype. Prevalence of EBV in NPC in countries such as Guatemala and Brazil has not been studied.

METHODS

We analyzed 19 cases of NPC, 11 from Guatemala and 8 from Brazil, for the presence of EBV by in situ hybridization and immunohistochemistry. Additionally, 19 hyperplastic adenoids from children were analyzed for EBV by in situ hybridization, 12 from Guatemala and 7 from Brazil.

RESULTS

All the NPC cases from Guatemala and 5 from Brazil were of the undifferentiated nonkeratinizing type. EBV-negative cases comprised 2 keratinizing NPC and 1 differentiated nonkeratinizing NPC. All undifferentiated nonkeratinizing NPC from both samples showed intense positivity for EBER, while LMP-1 only focally and scarcely expressed. EBER was positive in 75% and 43% of the adenoids from Guatemala and Brazil, respectively.

CONCLUSIONS

All undifferentiated nonkeratinizing NPC irrespective of origin from Guatemala or Brazil were highly associated with EBV.

HPV-related head and neck squamous cell carcinoma: An update and review

This is a review of human papilloma virus (HPV)-related head and neck squamous cell carcinoma (HNSCC). The epidemiology, pathology, clinical features, and risk factors of HPV-related HNSCC are discussed. HPV vaccines are also discussed.

Challenges in establishing the diagnosis of human papillomavirus-related oropharyngeal carcinoma

OBJECTIVES/HYPOTHESIS

To describe initial presentations and idiosyncrasies in establishing the diagnosis for human papillomavirus-related (HPV(+) ) compared to HPV-unrelated (HPV(-) ) oropharyngeal carcinoma (OPC).

STUDY DESIGN

A single institution retrospective series derived from an institutional prospectively compiled database supplemented by chart review.

METHODS

We reviewed consecutive OPC patients referred to an academic tertiary cancer center from 2009 to 2011. HPV status was evaluated by p16 staining. Signs/symptoms and procedures to establish diagnosis were recorded independently by two abstractors blinded to the HPV status during data retrieval. Initial presentations (signs/symptoms), interval, and the procedures to establish the diagnosis were compared between HPV(+) and HPV(-) OPC.

RESULTS

The most common initial presentation was an asymptomatic nodal mass for HPV(+) patients (n = 208; 69% vs. 29%, P < .001) in contrast to dysphagia/odynophagia for HPV(-) (n = 96; 34% vs. 63%, P < .001). Protracted interval (>12 months) from onset of signs/symptoms to diagnosis was observed in 18 (9%) HPV(+) versus three (3%) HPV(-) patients (P = .058). More HPV(+) patients required repeated (≥2) biopsy procedures (56% vs. 10%, P < .001). Misattribution to other disease occurred in eight (4%) HPV(+) patients (seven were mistaken as having a "branchial cleft cyst" when there were cystic lymph nodes and one as having a "lymphoma") compared to none in HPV(-) .

CONCLUSIONS

About two-thirds of HPV(+) patients present with an asymptomatic neck mass and often require multiple biopsy procedures to establish the diagnosis. Idiosyncrasies in appreciating the diagnostic setting (cystic lymph node, misattribution to other entities, or submucosal location of the tumor) or patient-related factors could delay the diagnosis of HPV(+) OPC.

LEVEL OF EVIDENCE

4 Laryngoscope, 126:2270-2275, 2016.

Squamous Cell Carcinoma of the Oral Cavity and Oropharynx

The most common malignancy to involve the oral cavity and oropharynx is squamous cell carcinoma (SCC). Because these oral cancers share an origin from the squamous epithelium, the pathology of oral SCC might be expected to be uniform and its diagnosis repetitive. In reality, the morphologic diversity in SCC, along with the propensity for reactive processes of the oral cavity to mimic SCC histologically, renders its diagnosis one of the more challenging in surgical pathology. This article discusses variants of oral and oropharyngeal SCC and highlights those features that help distinguish human papillomavirus-related from human papillomavirus-unrelated SCC.

Nasal Cavity and Paranasal Sinuses

The nasal cavity and paranasal sinuses occupy the top of the upper respiratory tract and form pneumatic spaces connected with the atmosphere. They are located immediately beneath the base of the cranium, where crucial vital structures are harbored. From this region, very much exposed to airborne agents, arise some of the more complex and rare benign and malignant lesions seen in humans, whose difficulties in interpretation make this remarkable territory one of the most challenging in the practice of surgical pathology.

Contents of this chapter cover inflammations and infections, polyps and pseudotumors, fungal and midfacial destructive granulomatous lesions, as well as benign, borderline, and malignant neoplasms. Among the neoplasms, emphasis is made on those entities characteristic or even unique for the sinonasal region, such as Schneiderian papillomas, glomangiopericytoma, intestinal- and non-intestinal-type adenocarcinomas, olfactory neuroblastoma, nasal-type NK-/T-cell lymphoma, and teratocarcinosarcoma. Moreover, recently recognized entities involving this territory, i.e., HPV-related non-keratinizing carcinoma, NUT carcinoma, and SMARCB1-deficient basaloid carcinoma, are also discussed in the light of their specific molecular findings. Furthermore, the text is accompanied by numerous classical and recent references, several tables, and 100 illustrations.

Biphenotypic human papillomavirus-associated head and neck squamous cell carcinoma: a report of two cases

Human papillomavirus-associated oropharyngeal squamous cell carcinoma is now recognised as a subtype of head and neck cancer with distinct clinical, molecular and histological characteristics. The majority of these carcinomas are of non-keratinising squamous type but there is a growing number of histomorphologic variants of this disease. Here we describe the clinical, histomorphologic and immunophenotypic features of two cases of human papillomavirus-associated oropharyngeal squamous cell carcinoma demonstrating a clearly delineated biphasic differentiated and undifferentiated phenotype.

Detection and genotype of high-risk human papillomavirus in fine-needle aspirates of patients with metastatic squamous cell carcinoma is helpful in determining tumor origin

OBJECTIVES

Recent studies have shown that human papillomavirus (HPV) is associated with a certain subset of head and neck squamous cell carcinoma (HNSCC)-namely, those arising in the oropharynx. The objective of this study is to determine the efficacy, detection, and genotype of high-risk (HR) HPV using the Roche cobas 4800 system (Roche Molecular System, Pleasanton, CA).

METHODS

Forty-two fine-needle aspirate (FNA) specimens from 37 patients with cervical (n = 36) or mediastinal (n = 5) lymphadenopathy or a left parapharyngeal mass (n =1) were included in this prospective study. HR-HPV testing was performed on residual FNA material after direct smear preparation and, if positive, was further delineated into HPV 16/18 genotypes using the Roche cobas 4800 system. Follow-up included review of histologic material and/or electronic health records.

RESULTS

Among those HNSCCs that were positive for HR-HPV, 18 (100%) of 18 originated from the oropharynx, whereas only two (13%) of 15 HR-HPV-negative HNSCCs originated from the oropharynx (χ(2) test, P < .05). p16 immunohistochemical assay and HPV 16 in situ hybridization on corresponding histologic specimens were concordant with cytologic HR-HPV results.

CONCLUSIONS

HR-HPV detection and genotyping can be performed on lymph node FNAs with metastatic squamous cell carcinoma using the Roche cobas 4800 system. The presence of HR-HPV and/or HPV 16 is a reliable indicator of the metastatic squamous cell carcinoma originating from the oropharynx.