Classification of tumors of the head and neck has evolved in recent decades including a widespread application of molecular testing in tumors of the sinonasal tract, salivary glands, and soft tissues with a predilection for the head and neck. The availability of new molecular techniques has allowed for the definition of multiple novel tumor types unique to head and neck sites. Moreover, an expanding spectrum of immunohistochemical markers specific to genetic alterations facilitates rapid identification of diagnostic molecular abnormalities. As such, it is currently possible for head and neck pathologists to benefit from a molecularly defined tumor classification while making diagnoses that are still based largely on histopathology and immunohistochemistry. This review covers the principal molecular alterations in sinonasal malignancies, such as alterations in DEK, AFF2, NUTM1, IDH1-2, and SWI/SNF genes in particular, that are important from a practical standpoint for diagnosis, prognosis, and prediction of response to treatment.

• Klíčová slova
• Head and neck, Molecular diagnostics, Next-generation sequencing, Sinonasal, Sinonasal tumor, Soft tissue,
• MeSH
• lidé MeSH
• nádorové biomarkery * genetika   analýza   MeSH
• nádory vedlejších dutin nosních * patologie   genetika   klasifikace   diagnóza   MeSH
• Světová zdravotnická organizace MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• nádorové biomarkery * MeSH

Classification of head and neck tumors has evolved in recent decades including a widespread application of molecular testing in tumors of the salivary glands, sinonasal tract, oropharynx, nasopharynx, and soft tissue. Availability of new molecular techniques allowed for the definition of multiple novel tumor types unique to head and neck sites. Moreover, the expanding spectrum of immunohistochemical markers facilitates a rapid identification of diagnostic molecular abnormalities. As such, it is currently possible for head and neck pathologists to benefit from a molecularly defined classifications, while making diagnoses that are still based largely on histopathology and immunohistochemistry. This review highlights some principal molecular alterations in head and neck neoplasms presently available to assist pathologists in the practice of diagnosis, prognostication and prediction of response to treatment.

• Klíčová slova
• Head and neck, Molecular diagnostics, Next-generation sequencing, Salivary gland, Sinonasal tumor, Soft tissue,
• MeSH
• imunohistochemie MeSH
• lidé MeSH
• molekulární patologie * MeSH
• nádory hlavy a krku * diagnóza   genetika   MeSH
• patologové MeSH
• slinné žlázy MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Diagnosis of salivary gland neoplasms is often challenging due to their high morphological diversity and overlaps. Several recurrent molecular alterations have been described recently, which can serve as powerful diagnostic tools and potential therapeutic targets (e.g. NTRK or RET fusions). However, current sequential molecular testing can be expensive and time consuming. In order to facilitate the diagnosis of salivary gland neoplasms, we designed an all-in-one RNA-based next generation sequencing panel suitable for the detection of mutations, fusions and gene expression levels (including NR4A3) of 27 genes involved in salivary gland neoplasms. Here we present the validation of the "SalvGlandDx" panel on FFPE histological specimen including fine needle aspiration (FNA) cell block material, against the standard methods currently used at our institution. In a second part we describe selected unique cases in which the SalvGlandDx panel allowed proper diagnosis and new insights into special molecular characteristics of selected salivary gland tumors. We characterize a unique salivary gland adenocarcinoma harboring a ZCCHC7-NTRK2 fusion, a highly uncommon spindle cell and pseudoangiomatoid adenoid-cystic carcinoma with MYBL1-NFIB fusion, and a purely oncocytic mucoepidermoid carcinoma, whereas diagnosis could be made by detection of a CRTC3-MAML2 rearrangement on the cell block specimen of the FNA. Further, a rare case of a SS18-ZBTB7A rearranged low-grade adenocarcinoma previously described as potential spectrum of microsecretory adenocarcinoma, is reported. In addition, features of six cases within the spectrum of polymorphous adenocarcinoma / cribriform adenocarcinoma of salivary gland including PRKD1 p.E710D mutations and novel fusions involving PRKAR2A-PRKD1, SNX9-PRKD1 and ATL2-PRKD3, are described.

• Klíčová slova
• Biopsy, Comprehensive, FNA, Molecular, Salivary gland neoplasm, Testing,
• MeSH
• biopsie MeSH
• fúzní onkogenní proteiny genetika   metabolismus   MeSH
• hybridizace in situ fluorescenční MeSH
• imunohistochemie metody   MeSH
• lidé MeSH
• mutace MeSH
• nádorové biomarkery * MeSH
• nádorové buněčné linie MeSH
• nádory slinných žláz diagnóza   farmakoterapie   genetika   MeSH
• staging nádorů MeSH
• stanovení celkové genové exprese * metody   MeSH
• stupeň nádoru MeSH
• vysoce účinné nukleotidové sekvenování * metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fúzní onkogenní proteiny MeSH
• nádorové biomarkery * MeSH

Laryngeal biopsies, contrary to biopsies from many other sites of the body, very often contain minute amounts of tumour tissue that may consist of morphologically undifferentiated tumour only. In haematoxylin- and eosin-stained sections, there may be no indicative features of what specific tumour entity that is present. In the larynx, particularly small round cell neoplasms, primary or metastatic, often cause a diagnostic dilemma and where an incorrect diagnosis can induce substantial clinical consequences for the patient (e.g., primary neuroendocrine carcinomas vs metastatic variants, certain sarcomas). If sufficient/representative material has been obtained, the application of immunohistochemistry and/or molecular techniques should in virtually every case reveal the true nature of the malignancy. In cases with sparse amount of material, and therefore a limited number of sections to be cut, a careful and thoughtful stepwise approach is necessary to ascertain a reliable diagnosis, or at least guide the clinician to the most likely diagnoses. With today's advanced and widely available technology with an abundance of markers to discriminate different tumours, the use of the term "undifferentiated" should be largely unnecessary. In the exceptional, and indeed exceedingly rare cases, when a classification is not possible, even after repeat biopsy, we suggest that the laryngeal neoplasm is better termed "unclassified malignant neoplasm" rather than "undifferentiated malignant neoplasm".

• Klíčová slova
• FISH, Immunohistochemistry, Larynx, RT-PCR, Unclassified malignancies,
• MeSH
• lidé MeSH
• nádory hrtanu klasifikace   diagnóza   patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH