Sinonasal tract mucoepidermoid carcinoma: a clinicopathologic and immunophenotypic study of 19 cases combined with a comprehensive review of the literature

[Interdisciplinary Management of Orbital Diseases]

Diagnosis and therapy of orbital diseases is an interdisciplinary challenge, in which i.e. otorhinolaryngologists, ophthalmologists, radiologists, radiation therapists, maxillo-facial surgeons, endocrinologists, and pediatricians are involved. This review article describes frequent diseases which both, otolaryngologists and ophthalmologists are concerned with in interdisciplinary settings. In particular the inflammatory diseases of the orbit including orbital complications, autoimmunological diseases of the orbit including Grave´s orbitopathy, and primary and secondary tumors of the orbit are discussed. Beside describing the clinical characteristics and diagnostic steps the article focusses on the interdisciplinary therapy. The review is completed by the presentation of most important surgical approaches to the orbit, their indications and possible complications. The authors tried to highlight the relevant facts despite the shortness of the text.

Re-evaluating a historic cohort of sinonasal and skull base mucoepidermoid carcinoma: an institutional experience

AIMS

Primary mucoepidermoid carcinomas (MECs) of the sinonasal tract and nasopharynx are rare entities that represent a diagnostic challenge, especially in biopsy samples. Herein, we present a case series of MECs of the sinonasal and skull base and its mimics to evaluate the clinicopathological and molecular characteristics in order to avoid misdiagnosis.

METHODS

We reviewed the pathology records of patients diagnosed from 2014 to 2022. Thirty MECs were consecutively diagnosed during that period.

RESULTS

Based on morphological and fluorescence in situ hybridization (FISH) analyses, 30 tumors originally diagnosed as MECs were separated into MAML2 fusion-positive (7 cases) and MAML2 fusion-negative groups (23 cases), in which 14 tumors were positive for the EWSR1::ATF1 fusion; these tumors were reclassified to have hyalinizing clear cell carcinoma (HCCC). The remaining nine MAML2 FISH negative cases were reconfirmed as squamous cell carcinoma (SCC, 3 cases) which showed keratinization and high Ki-67 expression; DEK::AFF2 carcinomas (2 cases), in which DEK gene rearrangement was detected by FISH; and MECs as previously described (4 cases) with typical morphological features. Including 7 MAML2 rearrangements tumors, 11 MEC cases had a male-to-female ratio of 4.5:1, and 6 tumors arose from the nasopharyngeal region, while 5 tumors arose from the sinonasal region. The prognosis of this series of salivary gland-type MECs was favorable.

CONCLUSIONS

Our study confirmed that HCCC runs the risk of being misdiagnosed as MEC in the sinonasal tract and nasopharynx, particularly with biopsy specimens. Careful histological evaluation with supporting molecular testing can facilitate pathological diagnoses.

Mucoepidermoid carcinoma showing continuity with the surface mucosa of the oral cavity: a report of 14 cases

OBJECTIVE

We aimed to characterize the histology and the clinicodemographic features of mucoepidermoid carcinoma (MEC), showing continuity with the oral surface mucosa.

STUDY DESIGN

We reviewed 138 cases of intraoral MEC to identify cases that showed continuity with the surface mucosa and compared their clinicodemographic findings with those of MECs not showing continuity. We compared the sex ratio using the 2-sample Z-test and compared the age distribution using the 2-sample Kolmogorov-Smirnov test.

RESULTS

Of the 138 cases examined, 14 showed continuity with the surface mucosa. Their histology showed surface mucosa with an apparent transition to an infiltrating tumor with mucous, intermediate, and epidermoid tumor cells growing in solid and cystic patterns. Their clinical appearance ranged from firm submucosal nodules to erythematous to ulcerated lesions. They showed a strong female predilection (6:1) and sharply bimodal age distribution, with sharp peaks in the fourth and seventh decades.

CONCLUSIONS

Mucoepidermoid carcinomas that show continuity have a demographic pattern distinct from that of conventional MECs, showing a striking female predilection and bimodal age distribution and suggesting a difference in etiology. Pathologists should remain aware that MEC in the oral cavity can have a histologic appearance of surface origin to reach the correct diagnosis.

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.

Mucoepidermoid carcinoma may be devoid of squamoid cells by immunohistochemistry: expanding the histologic and immunohistochemical spectrum of MAML2- rearranged salivary gland tumours

Mucoepidermoid carcinoma (MEC) is historically defined by a mix of squamoid, intermediate, and mucous cells, but we have recently encountered several cases lacking immunoreactivity for squamous markers p40, p63, and CK5/6 despite MAML2 fusions. This study will characterise these unique tumours. Ten MEC were collected arising from the parotid gland (n = 4), submandibular gland (n = 2), nasopharynx (n = 1), base of tongue (n = 1), bronchus (n = 1), and trachea (n = 1). Six tumours were low-grade, two intermediate-grade, one high-grade, and one demonstrated low-grade areas with high-grade transformation. Four cases were oncocytic, four had clear-cell features, two had spindle cell features, and one high-grade MEC had prominent solid, cord-like, and micropapillary features. The tumours were negative for p40 (10/10), p63 (10/10), and CK5/6 (9/9). Targeted RNA sequencing demonstrated CRTC1::MAML2 in five cases, CRTC3::MAML2 in two, and a novel MAML2::CEP126 in the unusual high-grade case. In two cases with insufficient RNA, MAML2 fluorescence in situ hybridisation (FISH) showed rearrangement. Genetically-confirmed MEC may lack overt squamous differentiation by histology and immunohistochemistry. While most cases harboured canonical fusions and fit within the spectra of MEC variants with oncocytic, clear cell, and/or spindle cell features, one had a novel MAML2::CEP126 fusion and unusual morphology. In MEC without squamoid cells, the use of immunohistochemistry may hinder, rather than aid, the correct diagnosis. In such cases, MAML2 analysis is most useful. The historical definition of MEC as a carcinoma with squamoid, intermediate and mucous cells should be revisited.

Mucoepidermoid carcinoma of the salivary glands revisited with special reference to histologic grading and CRTC1/3-MAML2 genotyping

Mucoepidermoid carcinoma (MEC) is the most common carcinoma of the salivary glands. Here, we have used two large patient cohorts with MECs comprising 551 tumors to study clinical, histological, and molecular predictors of survival. One cohort (n = 167), with known CRCT1/3-MAML2 fusion status, was derived from the Hamburg Reference Centre (HRC; graded with the AFIP and Brandwein systems) and the other (n = 384) was derived from the population-based Cancer Registry of North Rhine-Westphalia (LKR-NRW; graded with the AFIP system). The reliability of both the AFIP and Brandwein grading systems was excellent (n = 155). The weighted kappa for inter-rater agreement was 0.81 (95% CI 0.65-0.97) and 0.83 (95% CI 0.71-0.96) for the AFIP and Brandwein systems, respectively. The 5-year relative survival was 79.7% (95% CI 73.2-86.2%). Although the Brandwein system resulted in a higher rate of G3-MECs, survival in G3-tumors (AFIP or Brandwein grading) was markedly worse than in G1/G2-tumors. Survival in > T2 tumors was markedly worse than in those with lower T-stage. Also, fusion-negative MECs had a worse 5-year progression-free survival. The frequency of fusion-positive MECs in the HRC cohort was 78.4%, of which the majority (86.7%) was G1/G2-tumors. In conclusion, the AFIP and Brandwein systems are useful in estimating prognosis and to guide therapy for G3-MECs. However, their significance regarding young age (≤ 30 years) and location-dependent heterogeneity of in particular G2-tumors is more questionable. We conclude that CRTC1/3-MAML2 testing is a useful adjunct to histologic scoring of MECs and for pinpointing tumors with poor prognosis with higher precision, thus avoiding overtreatment.

Rare Diseases of the Nose, the Paranasal Sinuses, and the Anterior Skull Base

Due to their low incidence and thus resulting limited diagnostic criteria as well as therapeutic options, rare diseases of the nose, the paranasal sinuses, and the anterior skull base are a significant challenge. The value as of which a disease has to be considered as rare amounts to a maximum of 5 patients per 10 000 people. Within these diseases, however, there are extreme differences. Some rare or orphan diseases like for example the inverted papilloma belong to regularly diagnosed and treated diseases of larger departments of oto-rhino-laryngology whereas other rare diseases and malformations have only been described in less than 100 case reports worldwide. This fact emphasizes the necessity of bundling the available experience of diagnostics and therapy. The present article gives an overview about rare diseases of the nose, the paranasal sinuses, and the anterior skull base from the field of diseases/syndromes of the olfactory system, malformations of the nose and paranasal sinuses, ventilation and functional disorders as well as benign and malignant tumors. The classification and data on diagnostic and therapeutic options were established based on the current literature.

Infratemporal fossa surgical approaches to primary/recurrent malignancies of salivary origin: paradigm surgical shift, patient selection, and oncologic outcomes

PURPOSE OF REVIEW

To review, the surgical approaches available on diagnosing a patient with salivary gland malignancy in the infratemporal fossa (ITF). To comment on patient evaluation and method of treatment selection. To identify and report on patient outcome data and make recommendations on future needs.

RECENT FINDINGS

There is a need to define the anatomic boundaries contents of the ITF, masticator space, parapharyngeal space (PPS), pterygopalatine fossa, ventral skull base, and paramedian skull base, as evidence from publications. The pathological subtypes identified mainly include adenoid cystic and mucoepidermoid carcinomas. The source of these tumours originates from primary disease in the sinonasal tract and nasopharynx superiorly, and the PPS/deep lobe of parotid inferiorly. Current surgical options available, in suitable selected patient, available in tertiary head and neck cancer hospitals, which have available facilities and staffing is the endoscopic endonasal approach. This approach offers patients a 'complete margin-free surgical excision', minimal complications, shorter hospital stay, and no delay with commencement of any adjuvant treatment compared with the traditional 'open transcutaneous' approach.

SUMMARY

The current evidence specifically to the surgical management of salivary gland malignancy involving the ITF is sparse, with great difficult identifying treated patients and their details among a heterogeneous group of patients with many lesions. There is a need for patient data that have specific pathologic conditions to be amalgamated from such centers and publish on outcome events.

Effect of margin status and pathological grade in treatment of sinonasal mucoepidermoid carcinoma

OBJECTIVES

The purpose of this study was to investigate the association of demographic factors, grade, margin status, and treatment modalities for overall survival in patients with sinonasal mucoepidermoid carcinoma (SNMEC).

STUDY DESIGN

Retrospective database review.

METHODS

The National Cancer Database was queried for patients of all ages with SNMEC between 2004 and 2015. Univariate Kaplan-Meier and multivariate Cox regression analyses were performed to evaluate the association of suspected prognostic factors with overall survival. Subgroup analysis by margin status and grade was performed.

RESULTS

A total of 239 patients with SNMEC were included in the analysis. The 5-year overall survival was 63.6%. Prognostic factors associated with decreased survival include age over 70 years (P = .027), sphenoid primary site (P = .002), and advanced-stage malignancy (P = .024). Improved survival was associated with surgery achieving negative margins (P = .001). Adjuvant radiation was associated with improved survival (hazard ratio [HR] = 0.25, P = .015) in the negative-margin group but was not found to be a statistically significant factor in the positive-margin group (HR = 0.66, P = .509).

CONCLUSIONS

This investigation is the largest to date to analyze the association of treatment modalities with overall survival in SNMEC and subgroup analysis by histopathologic grade and surgical margin status of treatment outcomes. Surgery remains the mainstay of treatment in patients with SNMEC. However, administration of radiation may confer survival benefit to patients with negative margins.

LEVEL OF EVIDENCE

4 Laryngoscope, 2020.

Mucoepidermoid Carcinoma of the Lacrimal Sac: Clinical-Pathologic Analysis, Including Molecular Genetics

Purpose

The aim of this study was to assess whether mucoepidermoid carcinoma of the lacrimal sac is a counterpart of CRTC1/3-MAML2 gene fusion-related salivary gland mucoepidermoid carcinoma.

Methods

In this retrospective observational case series, pathology records were searched for all cases of lacrimal sac mucoepidermoid carcinoma diagnosed between 1990 and 2018. Data collected included demographics, clinical findings, management, and follow-up. Pathologic parameters assessed included tumor morphology, immunohistochemistry, and MAML2 and EGFR fluorescence in situ hybridization (FISH) studies.

Results

Six patients with mucoepidermoid carcinoma of the lacrimal sac, 5 males and 1 female, with a median age of 63 years (range 24-66) were identified. Five tumors were managed with radical resection and 1 patient underwent orbital exenteration. None of the patients developed recurrence or metastases with an average follow-up of 18 months (range 13-23). All tumors had morphologic and immunohistochemical features of mucoepidermoid carcinoma and overexpressed EGFR. MAML2 FISH was negative for MAML2 rearrangement in all tumors. EGFR FISH demonstrated EGFR amplification in 1 tumor.

Conclusions

Mucoepidermoid carcinoma of the lacrimal sac is not a lacrimal sac counterpart of CRTC1/3-MAML2 gene fusion-related salivary gland mucoepidermoid carcinoma. EGFR pathway activation and EGFR amplification in a subset of these neoplasms suggest the potential role for anti-EGFR agents.

Sinonasal mucoepidermoid carcinoma: a review of the National Cancer Database

BACKGROUND

Primary sinonasal mucoepidermoid carcinoma (SN-MEC) is a malignancy arising from seromucinous glands of the nasal cavity and paranasal sinuses. Given its rarity, few large-scale studies have been performed. In this study we describe the incidence and determinants of survival of patients with SN-MEC leveraging the National Cancer Database (NCDB).

METHODS

This was a retrospective, population-based cohort study of patients diagnosed with SN-MEC between 2004 and 2012 within the NCDB. The main outcome measure was overall survival (OS).

RESULTS

A total of 164 patients were identified. The cohort was composed of 47.6% males. Mean age at diagnosis was 59.7 years. The maxillary sinus was the most common primary site, accounting for 45.7% of cases. Eleven percent of patients presented with nodal disease, whereas 2.1% had distant metastases. Stage IV disease was seen in 30.4% of cases. A total of 79.8% of the patients underwent surgery, 61.0% received radiation therapy, and 15.1% had chemotherapy. OS at 1, 2, and 5 years was 83%, 77.0%, and 57%, respectively. On multivariate analysis, Medicaid insurance status (hazard ratio [HR], 7.29; 95% confidence interval [CI], 1.74-30.57), advanced tumor size (HR, 4.94; 95% CI, 1.19-20.5), and advanced nodal disease (N1: HR, 9.48; 95% CI, 1.66-54.23; N2B: HR, 19.3; 95% CI, 1.07-350.64) were associated with worse OS.

CONCLUSION

Mucoepidermoid carcinoma is the most common salivary gland malignancy but a rare sinonasal malignancy, with 5-year survival for SN-MEC approximating 50%. A significant proportion of patients present with advanced disease. Both socioeconomic factors and tumor characteristics are associated with survival.

Rare case report of an aggressive follicular lymphoid hyperplasia in maxilla

Follicular lymphoid hyperplasia is a very rare though benign reactive process of an unknown pathogenesis that may resemble a follicular lymphoma, clinically and histologically. Oral reactive follicular hyperplasia (RFH) has been described on the hard or soft palate and at the base of the tongue. We describe here the first case of RFH presenting as an aggressive tumor on the right posterior side of the maxilla in a 24-year-old male patient. The lesion had a clinical evolution of 18 months and was noticed after the surgical extraction of the right third molar, although we cannot assume a cause-effect relation with that surgical event whatsoever. His medical history was unremarkable. Following an incisional biopsy, histological examination revealed lymphoid follicles comprised by germinal centers surrounded by well-defined mantle zones. The germinal centers were positive for Bcl-6, CD10, CD20, CD21, CD23, CD79a, and Ki-67, while negative for Bcl-2, CD2, CD3, CD5, and CD138. The mantle and interfollicular zones were positive for Bcl-2, CD2, CD3, CD5, CD20, and CD138. Both areas were diffusively positive for kappa and lambda, showing polyclonality. The patient underwent a vigorous curettage of the lesion with no reoccurrences at 36 months of follow-up. This case report demonstrates that morphologic and immunohistochemical analyses are crucial to differentiate RFH from follicular lymphoma, leading to proper management.

Secondary mucoepidermoid carcinoma of the orbit

A 40-year-old man presented with right eye axial proptosis and ophthalmoplegia for 3 months. Imaging study showed a right intraconal mass with the erosion of the orbital floor. Incisional biopsy revealed mucoepidermoid carcinoma. Nasal endoscopy was normal and systemic tumor screening was negative for a primary source. The patient underwent right orbital exenteration, uncinectomy, nasal and maxillary mucosal biopsy. Malignant cells were found present in the mucosa of maxillary sinus roof and uncinate bone. The postoperative positron emission tomography scan showed residual active lesion in right orbital apex and maxilla but no primary lesion elsewhere. The patient subsequently underwent 35 cycles of postoperative radiotherapy. Primary mucoepidermoid carcinoma of the orbit is rare and typically arises from the lacrimal gland or sac. Those tumors not arising from lacrimal apparatus should be presumed metastatic in origin, and the thorough systemic survey should be undertaken in the search for the primary tumor.

Sinonasal Adenocarcinoma: Update on Classification, Immunophenotype and Molecular Features

Adenocarcinomas of the sinonasal tract may originate from respiratory surface epithelium or the underlying seromucinous glands. These malignancies are divided into salivary-type adenocarcinomas and non-salivary-type adenocarcinomas. The latter are further divided into intestinal-type and nonintestinal-type adenocarcinomas. This review provides an update on tumor classification, differential diagnostic considerations and molecular features, as well as new adenocarcinoma entities in the sinonasal area.

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.

miR-205 in situ expression and localization in head and neck tumors - a tissue array study

BACKGROUND

microRNAs are small non-coding RNA that control gene expression by mRNA degradation or translational inhibition. These molecules are known to play essential roles in many biological and physiological processes. miR-205 may be differentially expressed in head and neck cancers; however, there are conflicting data and localization of expression has yet to be determined.

MATERIALS AND METHODS

miR-205 expression was investigated in 48 cases of inflammatory, benign and malignant tumor tissue array of the neck, oronasopharynx, larynx and salivary glands by Locked Nucleic Acid in situ hybridization (LNA-ISH) technology.

RESULTS

miR-205 expression was significantly differentially expressed across all of the inflammatory, benign and malignant tumor tissues of the neck. A significant increase in miR-205 staining intensity (p<0.05) was observed from inflammation to benign and malignant tumors in head and neck tissue array, suggesting that miR-205 could be a biomarker to differentiate between cancer and non-cancer tissues.

CONCLUSIONS

LNA-ISH revealed that miR-205 exhibited significant differential cytoplasmic and nuclear staining among inflammation, benign and malignant tumors of head and neck. miR-205 was not only exclusively expressed in squamous epithelial malignancy. This study offers information and a basis for a comprehensive study of the role of miR-205 that may be useful as a biomarker and/or therapeutic target in head and neck tumors.

Review and Updates of Immunohistochemistry in Selected Salivary Gland and Head and Neck Tumors

Context

Immunohistochemistry is a useful tool for diagnosing salivary gland and head and neck tumors.

Objective

To review immunohistochemical markers, which can aid in the diagnosis of selected salivary gland and head and neck tumors.

Data Sources

Literature review and authors' personal practice experience.

Conclusions

Salivary gland and head and neck tumors include a large diverse group of tumors with complex and overlapping histologic features. Immunohistochemistry plays an important role in resolving the differential diagnosis of some salivary gland and head and neck tumors and can provide information for the prognosis of certain tumors.

Salivary mucoepidermoid carcinoma revisited

Clinicopathological features, prognosis and therapeutic strategies for mucoepidermoid carcinoma originating in salivary and salivary-type glands of the head and neck are reviewed. We emphasise histopathological aspects, appraise the value of histochemistry, electron microscopy, immunohistochemistry and cytophotometry, and discuss histogenesis and characteristic gene translocations. We additionally consider possible diagnostic difficulties, problems related to histological grading and accuracy of existing literature, and areas of controversy or uncertainty which may benefit from further investigations.

Salivary mucoepidermoid carcinoma: demonstration of transcriptionally active human papillomavirus 16/18

Herein we test the following hypotheses: (1) High-risk Human Papillomavirus (HR-HPV) may be involved in the etiology of mucoepidermoid carcinoma (MEC), and (2) The detection rate of HR-HPV in MEC has been increasing over time. Ninety-eight archival MEC specimens from three institutions spanning three decades were studied for HPV16/18 E6/E7 transcripts. RNA was extracted from formalin-fixed paraffin embedded specimens and HPV16/18 E6/E7 expression assessed by nested reverse transcription polymerase chain reaction (RT-PCR). A subset of MEC were also studied for MECT1-MAML2 fusion transcripts by nested RT-PCR and amplicon sequencing. The HPV expression data was validated by immunofluorescence (IF) with monoclonal HPV16/18 E6 antibody, PCR with the GP5+/6+ consensus primers, and sequencing of RT-PCR amplicons. HPV genome was localized by in-situ hybridization with the Ventana Inform HPVIII Family 16 probe. P16(INK4a) overexpression and aberrant p53 expression were assessed by immunohistochemistry. HPV16 E6/E7 transcripts were demonstrated in (29/98) 30% of MEC by RT-PCR. HPV18 E6/E7 transcripts were demonstrated in 13/98 (13%) of MEC by RT-PCR. Seven of 98 tumors (7%) demonstrated both HPV16/18. No significant association was found between HPV status and gender, age, and tumor site. All 13 HPV18+ MEC were diagnosed between 2001 and 2010, whereas 45 MEC diagnosed from 1977 to 2000 were negative for HPV18 (p = 0.002). By contrast, there was no significant difference with respect to HPV16 detection and date of diagnosis. All MEC that were positive for E6 protein were also HPV16/18 positive by RT-PCR. Sequencing a subset of RT-PCR amplicons confirmed HPV type- and region-specific sequences. PCR using GP5+/6+ consensus primers demonstrated HPV status concordance in 9 of 10 cases. DNA degradation was present in the last case; the RT-PCR amplicons were sequenced from this case which confirmed the presence of HPV type- and region-specific sequences. Strong (+4/+4) and diffuse (>50%) nuclear and cytoplasmic p16 expression was seen in 64% of MEC in the glandular regions, and 18% of MEC in the solid, squamoid regions. No correlation was seen between p16 expression and HPV status. Twenty-nine MEC (22 HPV+ and 7 HPV-negative) were selected for further evaluation for p53 expression. Strong aberrant nuclear p53 expression was present in only 2/22 HPV + MEC (9%, both Grade 3); no HPV-negative MEC demonstrated aberrant p53 expression. MECT1-MAML2 fusion transcripts were demonstrated in 23/37 (62%) MEC. No significant association was found between the presence of the MECT1-MAML2 fusion transcripts and tumor grade, HPV status, gender, era of diagnosis (2000 and earlier vs. 2001-2010) or tumor site. We demonstrate for the first time that transcriptionally active HPV16/18 is common to MEC. These findings were validated by demonstrating concordant results by separate PCR with consensus primers, and/or confirming the presence of HPV type- and region-specific sequences in the RT-PCR amplicons. We also visualized E6 viral oncoprotein and HPV genome within tumor cells. HR-HPV is thus potentially implicated in the pathogenesis of MEC. The frequency of HPV18 detection is significantly increased in MEC diagnosed after 2001, whereas we found no differences in the HPV16 detection rates per era of diagnosis.

The alveolar epithelial differentiation of glandular inner lining cells in a mucoepidermoid carcinoma of the lung: a case report

Mucoepidermoid carcinoma is a common malignant epithelial tumor of salivary glands, but relatively rare in lung. The histological features of mucoepidermoid carcinoma of the lung are similar to its counterpart arising from the salivary glands. Here, we reported a special tumor that occurred in the medial segment of the right lower lobe in a 22-year-old man. This tumor exhibited typical features of mucoepidermoid carcinoma with 3 cell types: squamoid cells, mucin-secreting cells and cells of intermediate type. These 3 types of cells organized into cysts, nests, glands and solid patterns. Specially, the inner lining cells of some glandular structures were uniform cuboidal and hobnail-like, similar to the alveolar epithelial cells. Immunohistochemistry staining revealed that the inner lining cells of glandular structures were positive for thyroid transcription factor-1 and surfactant protein-B, used as markers of alveolar epithelial cells, and were negative for p63. These findings for the first time demonstrated a rare alveolar epithelial differentiation of glandular inner lining cells in a mucoepidermoid carcinoma of the lung.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7095988968057804.

Sinonasal carcinomas: epidemiology, pathology, and management

Sinonasal carcinomas are uncommon neoplasms accounting for approximately 3% to 5% of all upper respiratory tract malignancies. Sinonasal malignancies in most cases do not cause early symptoms and present in an advanced stage of disease. Exact staging necessitates a clinical and endoscopic examination with biopsy and imaging. Tumor resection using an open or endoscopic approach is usually considered the first treatment option. In general, sinonasal carcinomas are radiosensitive, so adjuvant or neoadjuvant radiation treatment may be indicated in advanced disease. Multidisciplinary surgical and medical oncologic approaches, including ablation and reconstruction, have enhanced the survival outcome over the past few decades.

Sinonasal tract adenoid cystic carcinoma ex-pleomorphic adenoma: a clinicopathologic and immunophenotypic study of 9 cases combined with a comprehensive review of the literature

Primary sinonasal tract carcinoma ex-pleomorphic adenoma (CEPA) is very uncommon, with adenoid cystic carcinoma (ACC) CEPA exceptional. These tumors are often misclassified. This is a retrospective study. Nine cases of ACC CEPA included 7 females and 2 males, aged 39-64 years (mean, 51.1 years). Patients presented most frequently with obstructive symptoms (n = 5), epistaxis (n = 3), nerve changes or pain (n = 3), present for a mean of 25 months (men: 9.5 versus women: 29.4 months; p = 0.264). The tumors involved the nasal cavity alone (n = 5), nasopharynx (n = 2), or a combination of locations (n = 2) with a mean size of 2.9 cm (females: 3.3; males: 1.7; p = 0.064). Most patients presented at a low clinical stage (n = 7, stage I), with one patient each in stage II and IV, respectively. Histologically, the tumors showed foci of PA associated with areas of ACC. Tumors showed invasion (lymph-vascular: n = 4; perineural: n = 6; bone: n = 6). The neoplastic cells were arranged in tubules, cribriform and solid patterns, with peg-shaped cells arranged around reduplicated basement membrane and glycosaminoglycan material. Mitoses ranged from 0 to 33, with a mean of 8.7 mitoses/10 HPFs. Necrosis (n = 2) and atypical mitotic figures (n = 1) were seen infrequently. Immunohistochemical studies showed positive reactions for cytokeratin, CK5/6, p63, CK7, EMA, SMA, calponin, S100 protein and CD117, several highlighting luminal versus basal cells components. GFAP, CK20 and MSA were non-reactive. p53 and Ki-67 were reactive to a variable degree. Surgery (n = 8), accompanied by radiation therapy (n = 5) was generally employed. Five patients developed a recurrence, all of whom died with disease (mean, 8.4 years), while 4 patients are either alive (n = 2) or had died (n = 2) without evidence of disease (mean, 15.9 years). In summary, ACC CEPA probably arises from the minor mucoserous glands of the upper aerodigestive tract, usually presenting in patients in middle age with obstructive symptoms in a nasal cavity based tumor. Most patients present with low stage disease (stage I and II), although invasive growth is common. Recurrences develop in about a 55 % of patients, who experience a shorter survival (mean, 8.4 years) than patients without recurrences (mean, 15.9 years). The following parameters, when present, suggest an increased incidence of recurrence or dying with disease: bone invasion, lymph-vascular invasion, and perineural invasion.