Sinonasal Undifferentiated Carcinoma (SNUC): From an Entity to Morphologic Pattern and Back Again-A Historical Perspective.

Since the first description of sinonasal undifferentiated carcinoma (SNUC) as a distinctive highly aggressive sinonasal neoplasm with probable origin from the sinonasal mucosa (Schneiderian epithelium), SNUC has been the subject of ongoing study and controversy. In particular, the SNUC category gradually became a "wastebasket" for any undifferentiated or unclassifiable sinonasal malignancy of definite or probable epithelial origin. However, with the availability of more specific and sensitive immunohistochemical antibodies and increasing implementation of novel genetic tools, the historical SNUC category became the subject of progressive subdivision leading to recognition of specific genetically defined, reproducible subtypes.

Update on Neuroendocrine Carcinomas of the Larynx.

Objectives: Laryngeal neuroendocrine carcinomas are heterogeneous neoplasms characterized by neuroendocrine differentiation. Their prognoses are dependent on tumor type, therefore different classifications have been developed. Moreover, other tumors have overlapping pathologic features posing a range of diagnostic possibilities.

Salivary myoepithelial cells: an addendum.

Salivary myoepithelial cells bear particular appendages and are involved in processes that have received incomplete attention in previous reviews. Here, cilia on myoepithelial cells are reviewed as regards substructure, occurrence, detection (electron microscopy, double immunofluorescence together with confocal microscopy), and roles (sensory reception, evolutionary homology, paracrine interaction). Attention is drawn to regressive changes affecting those cells (e.

Data Set for the Reporting of Carcinomas of the Major Salivary Glands: Explanations and Recommendations of the Guidelines From the International Collaboration on Cancer Reporting.

The International Collaboration on Cancer Reporting is a nonprofit organization whose goal is to develop evidence-based, internationally agreed-upon standardized data sets for each anatomic site, to be used throughout the world. Providing global standardization of pathology tumor classification, staging, and other reporting elements will lead to achieving the objective of improved patient management and enhanced epidemiologic research. Salivary gland carcinomas are relatively uncommon, and as such, meaningful data about the many histologic types are not easily compared.

Ectomesenchymal Chondromyxoid Tumor: A Neoplasm Characterized by Recurrent RREB1-MKL2 Fusions.

Ectomesenchymal chondromyxoid tumor is a rare and benign neoplasm with a predilection for the anterior dorsal tongue. Despite morphologic heterogeneity, most cases are characterized by a proliferation of bland spindle cells with a distinctive reticular growth pattern and myxoid stroma. The immunophenotype of these neoplasms is likewise variable; most cases express glial fibrillary acid protein and S100 protein, with inconsistent reports of keratin and myoid marker expression.

Newly Described Entities in Salivary Gland Pathology.

Salivary glands may give rise to a wide spectrum of different tumors. This review concentrates on 4 salivary gland tumors that have been accepted in the recent literature as new neoplastic entities: mammary analog secretory carcinoma, cribriform adenocarcinoma of minor salivary glands (CASG), sclerosing polycystic adenosis/adenoma (SPA), and the mucinous/secretory variant of myoepithelioma. Mammary analog secretory carcinoma is a distinctive low-grade malignant salivary cancer that harbors a characteristic chromosomal translocation, t(12;15) (p13;q25), resulting in an ETV6-NTRK3 fusion.

Cervical Lymph Node Metastasis in Adenoid Cystic Carcinoma of the Larynx: A Collective International Review.

Adenoid cystic carcinoma (AdCC) of the head and neck is a well-recognized pathologic entity that rarely occurs in the larynx. Although the 5-year locoregional control rates are high, distant metastasis has a tendency to appear more than 5 years post treatment. Because AdCC of the larynx is uncommon, it is difficult to standardize a treatment protocol.

Cervical lymph node metastasis in adenoid cystic carcinoma of oral cavity and oropharynx: A collective international review.

The purpose of this study was to suggest general guidelines in the management of the N0 neck of oral cavity and oropharyngeal adenoid cystic carcinoma (AdCC) in order to improve the survival of these patients and/or reduce the risk of neck recurrences. The incidence of cervical node metastasis at diagnosis of head and neck AdCC is variable, and ranges between 3% and 16%. Metastasis to the cervical lymph nodes of intraoral and oropharyngeal AdCC varies from 2% to 43%, with the lower rates pertaining to palatal AdCC and the higher rates to base of the tongue.

Cervical Lymph Node Metastasis in High-Grade Transformation of Head and Neck Adenoid Cystic Carcinoma: A Collective International Review.

Adenoid cystic carcinoma (AdCC) is among the most common malignant tumors of the salivary glands. It is characterized by a prolonged clinical course, with frequent local recurrences, late onset of metastases and fatal outcome. High-grade transformation (HGT) is an uncommon phenomenon among salivary carcinomas and is associated with increased tumor aggressiveness.

Laryngeal Squamous Intraepithelial Lesions: An Updated Review on Etiology, Classification, Molecular Changes, and Treatment.

Laryngeal carcinogenesis is a multistep process, characterized by an accumulation of genetic changes associated with architectural and cytologic alterations, ranging from squamous hyperplasia to carcinoma in situ and encompassed by the terminology of squamous intraepithelial lesions (SILs). The etiology, classification, genetic changes, and malignant progression of these lesions are reviewed. Tobacco remains the principal etiological factor with gastroesophageal reflux disease recently considered as a possible factor.

Incidental findings of thyroid tissue in cervical lymph nodes: old controversy not yet resolved?

The clinical significance of papillary or follicular thyroid tissue incidentally discovered in cervical lymph nodes during pathological assessment of neck dissections for non-thyroid cancers of the upper aero-digestive tract is critically reviewed. Special emphasis is given to controversies over normal-looking, nodal, thyroid follicles. Arguments for and against the benign nature of these follicles are considered together with processes that could be involved in their formation.

Neuroendocrine neoplasms of the sinonasal region.

Neuroendocrine neoplasms of the sinonasal region, which are relatively uncommon but clinically very important, are reviewed here in the light of current knowledge. Using a definition for neuroendocrine based on phenotypic, histologic, immunohistochemical, and electron microscopic features rather than histogenetic criteria, sinonasal neuroendocrine carcinomas are examined with a particular emphasis on the small-cell and large-cell subtypes. This is followed by revisiting olfactory neuroblastoma because it is also a tumor that shows a neuroendocrine phenotype.

Rhabdomyoblastic Differentiation in Head and Neck Malignancies Other Than Rhabdomyosarcoma.

Rhabdomyosarcoma is a relatively common soft tissue sarcoma that frequently affects children and adolescents and may involve the head and neck. Rhabdomyosarcoma is defined by skeletal muscle differentiation which can be suggested by routine histology and confirmed by immunohistochemistry for the skeletal muscle-specific markers myogenin or myoD1. At the same time, it must be remembered that when it comes to head and neck malignancies, skeletal muscle differentiation is not limited to rhabdomyosarcoma.

Paraneoplastic syndromes in patients with laryngeal neuroendocrine carcinomas: clinical manifestations and prognostic significance.

Paraneoplastic syndromes are associated with a variety of malignant neoplasms and are systemic and non-metastatic manifestations that develop in a minority of cancer patients. This review examines all published cases of paraneoplastic syndromes associated with neuroendocrine carcinomas of the larynx. There are a total of ten patients reported with paraneoplastic syndromes associated with laryngeal neuroendocrine carcinomas in the literature.

Neuroepithelial structures associated with the subepithelial nerve plexus of taste buds: a fortuitous finding resembling the juxtaoral organ of Chievitz.

Numerous embryologic epithelial remnants are described in the oral region, when intimately associated with peripheral nerves, may pose a diagnostic pitfall for pathologists. The literature contains cases in which the juxtaoral organ of Chievitz (JOC) was identified in specimens removed because of a malignancy and the correct recognition of this structure potentially avoids unnecessary treatment. To our knowledge, this is the description of neuroepithelial structures similar to the JOC were found in the posterior tongue in close association with the subepithelial nerve plexus of taste buds.

Salivary gland tumor "wishes" to add to the next WHO Tumor Classification: sclerosing polycystic adenosis, mammary analogue secretory carcinoma, cribriform adenocarcinoma of the tongue and other sites, and mucinous variant of myoepithelioma.

This review is a continuation of suggested tumor additions to the next WHO Tumor Classification. The author will focus on four salivary gland entities that have recently become accepted in the literature as new neoplastic entities: sclerosing polycystic adenosis, mammary analogue secretory carcinoma, cribriform adenocarcinoma of the tongue and other sites, and mucinous variant of myoepithelioma.

Mucinous myoepithelioma, a recently described new myoepithelioma variant.

Myoepithelial neoplasms are tumors composed almost exclusively of cells with myoepithelial differentiation. They frequently contain spindle, plasmacytoid or epithelioid shaped cells and may have oncocytic or clear cytoplasmic features. They are uncommon, accounting for 1.

Molecular diagnostic alterations in squamous cell carcinoma of the head and neck and potential diagnostic applications.

Head and neck squamous cell carcinoma (HNSCC) is a common malignancy that continues to be difficult to treat and cure. In many organ systems and tumor types, there have been significant advances in the understanding of the molecular basis for tumorigenesis, disease progression and genetic implications for therapeutics. Although tumorigenesis pathways and the molecular etiologies of HNSCC have been extensively studied, there are still very few diagnostic clinical applications used in practice today.

Moderately differentiated neuroendocrine carcinoma (atypical carcinoid) of the parotid gland: report of three cases with contemporary review of salivary neuroendocrine carcinomas.

Primary neuroendocrine carcinomas (NECs) of the salivary glands are rare. Most reported NECs in that region are small cell carcinomas with few cases of large cell undifferentiated carcinoma and typical carcinoid tumors. Only two moderately differentiated NECs (atypical carcinoid tumors) have been previously reported.

Are biosafety practices in anatomical laboratories sufficient? A survey of practices and review of current guidelines.

Biosafety practices in anatomical pathology laboratories are crucial to prevent unnecessary exposures to both chemical and biological agents. Regulatory and guidance agencies have general regulations and recommendations regarding anatomical pathology laboratory biosafety practices. This study aimed to determine if professionals' perceptions and actual practice mirror these guidelines.