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.

DEK::AFF2 Carcinoma of the Sinonasal Tract and Skull Base: A Comprehensive Review

DEK::AFF2 carcinoma is an emerging entity of the sinonasal tract and skull base, commonly exhibiting exophytic and endophytic papillary growth, complex anastomosing trabeculae, monotonous cytomorphology, acantholytic change, and tumor-infiltrating neutrophils. A subset displays overt infiltration and high-grade features akin to non-keratinizing squamous cell carcinoma. Glandular differentiation may also be rarely present. The tumor shows frequent local recurrence and occasional distant metastasis. An accurate diagnosis requires the recognition of these key histologic features, followed by molecular confirmation. Recently, AFF2 immunohistochemistry has been demonstrated to be a sensitive and specific ancillary marker. This comprehensive review summarizes the current understanding of DEK::AFF2 carcinoma.

Prognostic implications across histological subtypes of head and neck squamous cell carcinoma: An update

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies worldwide, arising from the mucosal epithelium of the oral cavity, oropharynx, hypopharynx, nasopharynx, larynx, and sinuses. In addition to the conventional morphologic pattern characterized by the degree of cellular atypia and squamous differentiation, HNSCC is classified into eight histopathologic subtypes: basaloid, spindle cell, adenosquamous, cuniculatum, verrucous, lymphoepithelial, papillary, and acantholytic.

METHODS

This review provides a comprehensive review of the literature on the prognostic implications of the histological subtypes of HNSCC.

RESULTS

Although there is extensive literature on HNSCC, few studies specifically focus on the treatment and prognosis of its histopathologic subtypes. Among these subtypes, verrucous squamous cell carcinoma and carcinoma cuniculatum generally have a favorable prognosis, while others, such as basaloid and spindle cell squamous cell carcinoma, tend to follow a more aggressive clinical course.

CONCLUSION

In this review, we delve into the histopathological subtypes of HNSCC and explore their clinicopathological, molecular, and prognostic findings. Further molecular investigations aimed at identifying targeted therapies for these subtypes are necessary. Moreover, it is crucial to recognize the emerging histopathological variants documented in the literature, considering the ongoing limitations in prognostic assessment.

Adenosquamous cell carcinoma of the head and neck: a retrospective single institution series

Objectives

Head and neck adenosquamous cell carcinoma (HN-ASCC) is a rare, aggressive neoplasm, with limited data reported in the literature. The aim of this study was to assess tumour behaviour and prognostic factors impacting overall survival (OS) in a retrospective, single institution series.

Methods

A retrospective study on patients affected by HN-ASCC who were treated surgically between 2002 and 2019 at the Department of Otorhinolaryngology - Head and Neck Surgery of the University of Brescia was conducted. Demographics, clinical data, OS, and relative prognostic factors were analysed.

Results

The study included 32 patients, with a median age of 66 years, mostly males (84.4%) and untreated (68.8%). Adjuvant treatments followed surgery in 28.1% of patients. Compared to conventional SCC, ASCC showed a higher proportion of cases arising in the larynx (40.6%); no difference was found in other features. Advanced (pT3-4) local stage at presentation (p = 0.023), perineural invasion (PNI, p = 0.01), and positive margins (p = 0.007) were independent negative prognostic factors for OS.

Conclusions

HN-ASCC is a rare, aggressive cancer, most frequently arising in the larynx of elderly males, usually diagnosed in an advanced local stage. OS is generally poor, affected by local advanced stage, PNI, and positive resection margins.

HPV-associated oropharyngeal Adenosquamous carcinoma with early metastatic disease detected by ctDNA

Adenosquamous Carcinoma is a rare, aggresssive variant of squamous cell carcinoma that may HPV-driven in the oropharynx. Although it is reported to behave similar to HPV-related squamous cell carcinoma, the literature is very limited for this disease. We present a case of early T and N stage HPV + adenosquamous carcinoma of the tonsil that metastasized immediately following surgery and adjuvant therapy despite only having microscopic nodal burden. Circulating tumor DNA (ctDNA) was instrumental in recognizing and salvaging metastatic disease early with radiation.

Sinonasal Adenosquamous Carcinoma - Morphology and Genetic Drivers Including Low- and High-Risk Human Papillomavirus mRNA, DEK::AFF2 Fusion, and MAML2 Rearrangement

BACKGROUND

Sinonasal adenosquamous carcinoma is rare, and there are almost no studies detailing morphology or characterizing their genetic driver events. Further, many authors have termed sinonasal tumors with combined squamous carcinoma and glands as mucoepidermoid carcinoma but none have analyzed for the presence of MAML2 rearrangement.

METHODS

Cases from 2014 to 2020 were collected and diagnosed using World Health Organization criteria. They were tested for p16 expression by immunohistochemistry (70% cut-off), DEK::AFF2 fusion by fluorescence in situ hybridization (FISH) and AFF2 immunohistochemistry, MAML2 rearrangement by FISH, and low- and high-risk HPV by RNA ISH and reverse transcription PCR, respectively. Detailed morphology and clinical features were reviewed.

RESULTS

There were 7 male (64%) and 4 female (36%) patients with a median age of 69 years, most Caucasian (10 of 11 or 91%). Most had tobacco exposure (8/11, 73%) and most presented with epistaxis, a visible nasal mass, and/or facial pain. Several had a precursor papillomas (3 of 11, 27%). The squamous component had variable keratinization, 5 of 11 (46%) of which would be described as keratinizing, 3 non-keratinizing, and 2 with mixed features. All had gland formation, by definition, and 2 of 11 (18%) had ciliated tumor cells. None of the 11 cases had MAML2 rearrangement and one had DEK::AFF2 fusion with associated positive nuclear AFF2 protein immunostaining. Most were p16 positive (7 of 11, 64%) and all 7 of these were hrHPV positive either by RNA ISH or RT-PCR. Two of the p16-negative tumors were positive for lrHPV by RNA ISH. Treatment included surgery alone (4 of 11, 36%), surgery with adjuvant radiation (5 of 11, 45%), and surgery with radiation and chemotherapy (2 of 11, 18%). Four of 11 patients (36%) suffered disease recurrence, two requiring re-operation and who were disease free at last follow-up, one receiving additional chemotherapy and who was alive with disease. The other elected to undergo palliative therapy and died of disease.

CONCLUSION

Sinonasal adenosquamous carcinoma is a somewhat heterogeneous tumor not infrequently arising ex papilloma and having various drivers including high- and low-risk HPV and rarely DEK::AFF2 fusion. The prognosis appears favorable when proper treatment is possible.

Adenosquamous Carcinomas and Mucinous Adenocarcinoma of the Minor Salivary Glands: Immunohistochemical and Molecular Insights

There is confusion about the diagnosis, histogenesis and taxonomical efforts regarding adenosquamous carcinomas (ASCs) and mucinous adenocarcinomas (MACs), especially with calls for reconsidering the nature of high-grade mucoepidermoid carcinoma (MEC). This study aims to compare the genetic profiles of ASCs and MACs that have been previously reported in the literature and investigate if either ASC or MAC is closer in genetic mutations to high-grade MEC. Systematic searches in the NCBI, Web of Science, and Scopus databases were performed between January 2000 and August 2022. The retrieved genetic mutations were processed and annotated. Protein–protein network analysis was conducted for each neoplasm. The results were viewed and discussed in terms of molecular oncogenesis of ASCs and MACs at different topographies. Molecular profile mapping was conducted by annotating all the retrieved genes for each neoplasm using genetic network analysis (Cystoscape software program). The genetic profile of each lesion was compared to that of high-grade MEC. To conclude, both genetic profiles do not tend to intersect specifically with high-grade MEC, except for the generic mutations commonly detected in all high-grade head and neck tumors. However, the availability of data on the molecular profile of each lesion limits the generalizability of the findings of this study.

Adenosquamous Carcinoma with the Acantholytic Feature in the Oral Cavity: A Case Report and Comprehensive Literature Review

Adenosquamous carcinoma (ASC) is an aggressive subtype of squamous cell carcinoma (SCC). Due to its poor prognosis, a precise pathological diagnosis of ASC is essential but challenging because its pathological criteria are still unclear. Here, we present a rare case of oral ASC accompanied by acantholytic features. The tumor was raised in the mandibular gingiva and recurred locally approximately 13 months after the initial surgery with cervical lymph node metastasis. Pathological specimens of the primary lesion showed acantholysis in a large area of the SCC. Mucous cells, the characteristic finding indicating glandular differentiation, were imperceptible in the initial surgical specimen but increased in the locally recurrent and metastatic lymph node specimens. In a comprehensive literature review of oral ASC cases, the present case was the only case of ASC with acantholytic features. We reconfirmed that ASC has poor prognoses, such as low 5-year overall survival and disease-free survival, high locoregional recurrence, and high distant metastasis rates. A precise diagnosis of ASC is required for estimating prognosis and undergoing close follow-up, even if the adenocarcinomatous component is limited to a small area in the lesion.

Mucoepidermoid carcinoma (MEC) and adenosquamous carcinoma (ASC), the same or different entities?

Mucoepidermoid carcinoma (MEC) and adenosquamous carcinoma (ASC) have overlapping histopathological appearances and sites of occurrence, which may cause diagnostic difficulty impacting subsequent treatment. We conducted a systematic review of the scientific literature to determine whether molecular alterations were sufficiently different in MEC and ASC to aid in classifying the two entities. We searched Medline, Embase and Web of Science for studies reporting molecular determinations of ASC and/or MEC and screened retrieved records for eligibility. Two independent researchers reviewed included studies, assessed methodological quality and extracted data. Of 8623 identified records, 128 articles were included for analysis: 5 which compared the two tumors in the same investigation using the same methods and 123 which examined the tumors separately. All articles, except one were case series of moderate to poor methodological quality. The 5 publications examining both tumors showed that 52/88 (59%) MEC and 0% of 110 ASC had rearrangement of the MAML2 gene as detected by FISH and/or RT-PCR, but did not investigate other genes. In the entire series MEC had MAML2 gene rearrangement in 1337/2009 (66.6%) of tumors studied. The articles examining tumors separately found that MEC had mutations in EGFR (11/329 cases, 3.3%), KRAS (11/266, 4.1%) and ERBB2 (9/126, 7.1%) compared with ASC that had mutations in EGFR (660/1705, 38.7%), KRAS (143/625, 22.9%) and ERBB2 (6/196, 3.1%). The highest level of recurrent mutations was in pancreatic ASC where (108/126, 85.7%) reported mutations in KRAS. The EGFR mutations in ASC were similar in number and kind to those in lung adenocarcinoma. By standards of systematic review methodology and despite the large number of retrieved studies, we did not find adequate evidence for a distinctive molecular profile of either MEC or ASC that could definitively aid in its classification, especially in histologically difficult cases that are negative for MAML2 rearrangement. The case series included in this review indicate the relevance of MAML2 rearrangement to support the diagnosis of MEC, findings that should be confirmed by additional research with adequate study design.

Primary Mucoepidermoid Carcinoma of the Lacrimal Apparatus

PURPOSE

In this study, we evaluated the clinicopathologic and molecular characteristics of lacrimal apparatus mucoepidermoid carcinoma (MEC) to define its typical diagnostic features.

DESIGN

Retrospective observational case series.

METHODS

Institutional pathology records between 2011 and 2021 were searched for all cases of lacrimal apparatus MEC.

RESULTS

A total of 2 male and 6 female patients ranging in age from 18 to 83 years (median 56, mean 54) were included. Six lacrimal apparatus MECs were found in the lacrimal gland, and 2 cases occurred in the lacrimal sac and nasolacrimal duct. Histologically, there were 6 cases of conventional MEC, 1 clear-cell variant of MEC, and 1 oncocytic variant of MEC for a total of 8 cases. There were 3 low-grade cases and 5 high-grade cases. All 8 cases were evaluated via immunohistochemistry, and the results were positive (scores 1-4) for pankeratin, 34betaE12, p63, p40, CK7, CK8, and CK19, with a relatively higher expression of p63 observed in high-grade MEC. The presence of human papillomavirus (HPV) type 6 DNA was found in 4 patients. MAML2 fluorescence in situ hybridization was positive for MAML2 rearrangement in 3 lacrimal gland tumors (2 low-grade and 1 high-grade). Six tumors were managed with radical resection, and 2 patients underwent orbital exenteration. Postoperative radiation therapy was delivered to 6 patients, and chemotherapy was administered to 1 patient.

CONCLUSIONS

MECs of the lacrimal apparatus are rare tumors, and the rate of MAML2 translocations is lower than that in salivary MECs. Lacrimal gland and lacrimal sac MECs may not be of the same subtypes intrinsically because of the difference in MAML2 translocation, anatomy, and clinical course. The etiologic function of HPV type 6 infection should be explored in lacrimal apparatus MECs. Radical surgery is the treatment of choice. The description of these unique findings may assist in the definitive diagnosis of and improve our understanding of lacrimal apparatus MEC.

Diagnostic Value of MAML2 Rearrangements in Mucoepidermoid Carcinoma

Mucoepidermoid carcinoma (MEC) is often seen in salivary glands and can harbor MAML2 translocations (MAML2+). The translocation status has diagnostic utility as an objective confirmation of the MEC diagnosis, for example, when distinction from the more aggressive adenosquamous carcinoma (ASC) is not straightforward. To assess the diagnostic relevance of MAML2, we examined our 5-year experience in prospective testing of 8106 solid tumors using RNA-seq panel testing in combinations with a two-round Delphi-based scenario survey. The prevalence of MAML2+ across all tumors was 0.28% (n = 23/8106) and the majority of MAML2+ cases were found in head and neck tumors (78.3%), where the overall prevalence was 5.9% (n = 18/307). The sensitivity of MAML2 for MEC was 60% and most cases (80%) were submitted for diagnostic confirmation; in 24% of cases, the MAML2 results changed the working diagnosis. An independent survey of 15 experts showed relative importance indexes of 0.8 and 0.65 for "confirmatory MAML2 testing" in suspected MEC and ASC, respectively. Real-world evidence confirmed that the added value of MAML2 is a composite of an imperfect confirmation test for MEC and a highly specific exclusion tool for the diagnosis of ASC. Real-world evidence can help move a rare molecular-genetic biomarker from an emerging tool to the clinic.

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.

Differential diagnosis and treatment of salivary secretory carcinoma and acinic cell carcinoma

Secretory carcinoma (SC) and acinic cell carcinoma (AciCC) are two rare tumors originating in the salivary gland of the head and neck. Before the World Health Organization (WHO) classified SC as a new entity in 2017, the majority of SC cases were incorrectly diagnosed as AciCC. Indeed, they are similar in biological behaviors, clinical manifestations and histomorphological features. Especially, SC and zymogen granule-poor AciCC are difficult to differentiate, which brings a tough challenge in clinical diagnosis. This article provides an updated understanding of the differential diagnosis in SC and AciCC from two main perspectives: histopathology and molecular genetics. The targeted therapies for both tumors are also mentioned. It aims to give some hints in clinical diagnosis and treatment, in hopes that patients with adequate diagnosis could obtain the opportunityformore effective treatment.

Adenosquamous carcinoma of the digestive system: a literature review

Adenosquamous carcinoma (ASC), containing both adenocarcinoma and squamous cell carcinoma components, is rare in the digestive system. Limited data is available on ASC of the digestive system (AS-ASC), and the current evidence is available mainly in the form of case reports and case series. We performed a thorough search of the available literature and compiled a review on the epidemiology, histopathology, pathogenesis, clinical manifestations, diagnosis, treatment, and prognosis of AS-ASC. Non-specific clinical and imaging presentations and low diagnostic accuracy of biopsy lead to difficulties in preoperative diagnosis in a high proportion of patients and high malignancy. The pathogenesis remains obscure. Surgery remains the mainstay of treatment for AS-ASC. The role of chemoradiotherapy as an adjuvant treatment is still inconclusive. Key messages Metastatic linings and the lack of efficacious treatments lead to an unfavorable outcome in AS-ASC patients. Further research could help us understand the pathophysiology of AS-ASCand the unique needs of AS-ASC patients.

Conjunctival 'mucoepidermoid carcinoma' revisited: a revision of terminology, based on morphologic, immunohistochemical and molecular findings of 14 cases, and the 2018 WHO Classification of Tumours of the Eye

In 2018, the consensus meeting for the WHO Classification of Tumours of the Eye decided that conjunctival mucoepidermoid carcinoma should be reclassified as adenosquamous carcinoma, as this represented a better morphological fit. To examine the applicability of this terminology, we studied the clinical, histopathological, immunohistochemical and molecular pathology of 14 cases that were originally diagnosed as conjunctival mucoepidermoid carcinoma. There were 7 (50%) females and 7 (50%) males. The median age was 64 years. The left eye was affected in 8 and the right eye in 6 patients. In-situ carcinoma was present in 11/14 (79%) cases and comprised in-situ squamous cell carcinoma (SCC) and conjunctival intraepithelial neoplasia with mucinous differentiation (CIN-Muc). Invasive carcinoma was present in 11/14 (79%) cases. Group 1 (1/11 cases, 9%) comprised invasive SCC only. Group 2 (6/11 cases, 55%) comprised SCC with mucinous differentiation, manifesting as scattered intracellular mucin, occasionally together with intercellular mucin, with no evidence of true glandular differentiation. Group 3 (3/11 cases. 27%) comprised true adenosquamous carcinoma. Group 4 (1/11 cases, 9%) comprised pure adenocarcinoma. Thirteen of 14 cases (93%) underwent FISH for MAML2 translocation and none were rearranged. Two cases harboured high-risk HPV (type 16 and 18). The combined findings confirm that all lesions in our study were not mucoepidermoid carcinoma, but represented predominantly SCC with mucinous differentiation and adenosquamous carcinoma. We, therefore, recommend future revision of the WHO classification to include SCC with mucinous differentiation alongside adenosquamous carcinoma.

Navigating small biopsies of salivary gland tumors: a pattern-based approach

Diagnosis of salivary gland tumors on small biopsy can be difficult because of overlapping morphology, limited tissue availability, and technical artifact. Although a specific diagnosis is not feasible in all cases, a cautious and thoughtful approach to the differential diagnosis and a keen awareness of clinical consequences can facilitate the most complete and useful classification possible. In this review, we present a general strategy for the evaluation of small salivary biopsies, including consideration of clinical and radiographic information, systematic assessment of histologic patterns, and judicious use of immunohistochemistry and molecular studies. We then focus on the distinctive differential diagnoses raised by 6 specific histologic patterns: tubular and cribriform architecture, squamous differentiation, mucin and other secretions, high-grade cytology, epithelial and lymphoid elements, and oncocytic features. Throughout this systematic and pattern-based approach, we focus on practical and cost-effective strategies to overcome the most common diagnostic challenges in limited material.

The Role of Ancillary Techniques in Salivary Gland Cytopathology Specimens

Salivary gland tumor aspiration cytology is a useful preoperative test to guide the most appropriate clinical and surgical management for these patients. Although salivary gland cytology is often useful to distinguish between non-neoplastic lesions, benign neoplasms and malignant neoplasms, there remain many challenges in this area. Specifically, these tumors are uncommon and may have considerable morphologic overlap, especially in the setting of a malignant tumor. This article reviews some of the immunohistochemical and molecular characteristics of more common salivary gland neoplasms that pathologists and cytotechnologists may encounter. When used in combination with morphologic features, such ancillary testing can be useful to further refine the differential diagnosis, more strongly favor a particular entity, or in some instances confidently provide a specific diagnosis.

Challenges in Minor Salivary Gland Biopsies: A Practical Approach to Problematic Histologic Patterns

Evaluation of minor salivary gland biopsy can be fraught with a wide range of problems, including technical limitations due to the small size and distorted nature of tissue received and interpretive difficulties navigating the considerable morphologic and immunohistochemical overlap between widely disparate entities. As such, common pathologic findings can evoke a perplexing differential diagnosis that encompasses malignant, benign, and non-neoplastic processes. This review will present the diagnostic considerations that arise from four histologic patterns that are frequently encountered on minor salivary gland biopsies: squamous differentiation, tubular and cribriform growth, mucin production, and myxoid stroma. The discussion herein will emphasize practical strategies and priorities for navigating these differential diagnoses in a clinically-relevant and cost-effective manner.

The Role of Molecular Testing in the Differential Diagnosis of Salivary Gland Carcinomas

Salivary gland neoplasms are a morphologically heterogenous group of lesions that are often diagnostically challenging. In recent years, considerable progress in salivary gland taxonomy has been reached by the discovery of tumor type-specific fusion oncogenes generated by chromosome translocations. This review describes the clinicopathologic features of a selected group of salivary gland carcinomas with a focus on their distinctive genomic characteristics. Mammary analog secretory carcinoma is a recently described entity characterized by a t(12;15)(p13;q25) translocation resulting in an ETV6-NTRK3 fusion. Hyalinizing clear cell carcinoma is a low-grade tumor with infrequent nodal and distant metastasis, recently shown to harbor an EWSR1-ATF1 gene fusion. The CRTC1-MAML2 fusion gene resulting from a t(11;19)(q21;p13) translocation, is now known to be a feature of both low-grade and high-grade mucoepidermoid carcinomas associated with improved survival. A t(6;9)(q22-23;p23-34) translocation resulting in a MYB-NFIB gene fusion has been identified in the majority of adenoid cystic carcinomas. Polymorphous (low-grade) adenocarcinoma and cribriform adenocarcinoma of (minor) salivary gland origin are related entities with partly differing clinicopathologic and genomic profiles; they are the subject of an ongoing taxonomic debate. Polymorphous (low-grade) adenocarcinomas are characterized by hot spot point E710D mutations in the PRKD1 gene, whereas cribriform adenocarcinoma of (minor) salivary glands origin are characterized by translocations involving the PRKD1-3 genes. Salivary duct carcinoma (SDC) is a high-grade adenocarcinoma with morphologic and molecular features akin to invasive ductal carcinoma of the breast, including HER2 gene amplification, mutations of TP53, PIK3CA, and HRAS and loss or mutation of PTEN. Notably, a recurrent NCOA4-RET fusion has also been found in SDC. A subset of SDC with apocrine morphology is associated with overexpression of androgen receptors. As these genetic aberrations are recurrent they serve as powerful diagnostic tools in salivary gland tumor diagnosis, and therefore also in refinement of salivary gland cancer classification. Moreover, they are promising as prognostic biomarkers and targets of therapy.

Adenosquamous Carcinoma of the Tongue

A 51-year-old white female presented with a painful ulcer of the left ventrolateral tongue. An incisional biopsy confirmed a diagnosis of adenosquamous carcinoma. The adenosquamous carcinoma is an uncommon malignant tumor with histopathological features of a squamous carcinoma and an adenocarcinoma. A definitive diagnosis requires histopathological examination of a deep biopsy involving the submucosal tissue. This malignant tumor shows aggressive behavior with early invasive growth and a poor prognosis. The histopathological findings and differential diagnosis of a case of adenosquamous carcinoma of the tongue are discussed.

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.

Oral Adenosquamous Carcinoma Mimicking a Pyogenic Granuloma: a Challenging Diagnosis

Adenosquamous carcinoma is an aggressive variant of squamous cell carcinoma. This report describes a case of adenosquamous carcinoma with clinical features of a benign lesion and discusses the differential diagnoses, especially regarding histopathological and immunohistochemical analyses. A 45-year-old male was referred to our outpatient clinic complaining about a rapid-growing enlargement in hard palate. Clinical examination revealed an erythematous and pedunculated nodule with lobulated non-ulcerated surface. Excisional biopsy was performed following clinical diagnosis of pyogenic granuloma. Histologically, the specimen consisted of areas characterizing both well-differentiated squamous cell carcinoma and true adenocarcinoma. After a broad list of immunohistochemical markers was evaluated (AE1/AE3, CEA, CK5, CK7, CK8/18, p53, p63 and Ki67), the diagnosis of adenosquamous carcinoma was rendered and the patient referred to complementary surgery. Adenosquamous carcinoma represents a challenge in diagnostic routine due to its rarity, diverse range of clinical presentations and histological features. Furthermore, classical clinical benign features may be present in malignant lesions; hence the submission of every surgical specimen to histological analysis is mandatory to provide the patient the adequate treatment.

New Developments in Salivary Gland Pathology: Clinically Useful Ancillary Testing and New Potentially Targetable Molecular Alterations

Accurate diagnosis of salivary gland tumors can be challenging because of the many diagnostic entities, the sometimes extensive morphologic overlap, and the rarity of most tumor types. Ancillary testing is beginning to ameliorate some of these challenges through access to newer immunohistochemical stains and fluorescence in situ hybridization probes, which can limit differential diagnostic considerations in some cases. These ancillary testing strategies are especially useful in small biopsy samples, including aspiration cytology. Molecular techniques are also expanding our understanding of salivary gland tumor pathology and are helping to identify potential targets that may improve treatment for some of these tumors. Here, we summarize the clinical use of new immunohistochemical markers in our practice and review the current understanding of chromosomal rearrangements in salivary gland tumor pathology, emphasizing the prospects for exploiting molecular alterations in salivary gland tumors for diagnosis and targeted therapy. We find that immunohistochemistry and fluorescence in situ hybridization are powerful tools toward the diagnosis of salivary gland tumors, especially when used in a systematic manner based on morphologic differential-diagnostic considerations. As new targeted therapies emerge, it will become increasingly vital to incorporate appropriate molecular testing into the pathologic evaluation of salivary gland cancers.

Update from the 4th Edition of the World Health Organization of Head and Neck Tumours: Tumours of the Oral Cavity and Mobile Tongue

There have been several additions and deletions in Chapter 4 on Tumours of the oral cavity and mobile tongue in the 2017 fourth edition of the World Health Organization Classification of Tumours of the Head and Neck. This chapter excludes the oropharynx, which now is a stand-alone chapter acknowledging the uniqueness of the oropharynx from the oral cavity. New entries in Chapter 4 include rhabdomyoma, haemangioma, schwannoma, neurofibroma and myofibroblastic sarcoma in the section titled Soft tissue and neural tumours. Discussion of salivary gland entities have been reduced and includes mucoepidermoid carcinoma and pleomorphic adenoma as the other salivary gland types are discussed elsewhere. In the Haematolymphoid tumours section, like the salivary gland section, only tumors that commonly present in the oral cavity are discussed in Chapter 4. Excluded entities in the updated classification include papillary hyperplasia, median rhomboid glossitis, keratoacanthoma, focal oral mucinosis, and secondary tumors. This article will summarize the changes in the new classification since the 2005 edition focusing on selected entities that have had significant changes along with new entries.

Applications of molecular testing in surgical pathology of the head and neck

Molecular testing in routine surgical pathology is becoming an important component of the workup of many different types of tumors. In fact, in some organ systems, guidelines now suggest that the standard of care is to obtain specific molecular panels for tumor classification and/or therapeutic planning. In the head and neck, clinically applicable molecular tests are not as abundant as in other organ systems. Most current head and neck biomarkers are utilized for diagnosis rather than as companion diagnostic tests to predict therapeutic response. As the number of potential molecular biomarker assays increases and cost pressures escalate, the pathologist must be able to navigate the molecular testing pathways. This review explores scenarios in which molecular testing might be beneficial and cost-effective in head and neck pathology.

Adenosquamous Carcinoma of the Head and Neck: A Case-Control Study with Conventional Squamous Cell Carcinoma

Adenosquamous carcinoma (AdSC) is considered a rare variant of squamous cell carcinoma (SCC) which is considered to be more clinically aggressive. Data is very limited with very little case matched data on outcomes in the literature. It is also unknown whether the quantity of the adenocarcinoma component affects outcomes. A retrospective case-control study with 23 cases of AdSC and 1137 SCC controls was conducted. Cases were matched by anatomic subsite, treatment, and, for oropharynx, by p16 status. The following variables were adjusted for in the analysis: T classification (T1/T2 vs. T3/T4), N classification (N0-N2a vs. N2b-N3), age, and smoking. The adenocarcinoma component was quantified by the number of high power fields containing glands as low, moderate, or high. AdSCs had a significantly greater risk of disease recurrence but largely, the differences were not statistically significant. The quantity of adenocarcinoma did not correlate with disease recurrence or survival. This case-control study on AdSC shows modestly more clinically aggressive behavior than conventional SCC, even while controlling for p16 status for oropharyngeal cases. Further, it suggests the current definition of AdSC, with no minimum requirement for gland formation, is clinically accurate.