Adenoid cystic carcinoma (AdCC) is one of the most common salivary gland malignancies and occurs in all major and minor salivary gland and seromucous gland sites. AdCCs of salivary gland origin have long been categorized as fusion-defined carcinomas owing to the almost consistent presence of fusion genes MYB::NFIB , or less commonly MYBL1::NFIB. We collected a cohort of 95 cases of AdCC, which were largely characterized by canonical fusions MYB::NFIB (49 cases) or MYBL1::NFIB (9 cases). In additional 11 cases of AdCC, rearrangements in MYB or NFIB genes were detected by FISH. In addition, NGS revealed novel noncanonical fusion transcripts EWSR1::MYB ; ACTB::MYB; ESRRG::DNM3, MYB::TULP4 , and ACTN4::MYB , each of them in 1 case. The tumors that showed noncanonical fusions had features of metatypical AdCC with a diverse architecture, lobulated multinodular growth pattern, and hypercellular peripheral palisading of nuclei (2 cases), tubular hypereosinophilia (2 cases), and pale eosinophilic to vacuolated (bubbly) cytoplasm (3 cases). Our study documented 3 cases of AdCC of salivary glands harboring novel gene fusions TULP4::MYB , ACTN4::MYB , and ACTB::MYB , in 1 case each, which have not been described before. A rare EWSR1::MYB fusion was detected in 1 case. Moreover, 1 case of sinonasal metatypical AdCC showed EWSR1 rearrangement detected by FISH. Also, 1 case with an ESRRG::DNM3 fusion of unknown significance is described in this study. These discoveries illustrate how broad molecular profiling will expand understanding of changes in known entities.

• Klíčová slova
• adenoid cystic carcinoma, salivary gland neoplasm, sinonasal,
• MeSH
• adenoidně cystický karcinom * genetika   patologie   MeSH
• dospělí MeSH
• fúze genů MeSH
• fúzní onkogenní proteiny * genetika   MeSH
• genetická predispozice k nemoci MeSH
• genová přestavba MeSH
• hybridizace in situ fluorescenční MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• nádorové biomarkery * genetika   MeSH
• nádory slinných žláz * genetika   patologie   MeSH
• protein EWS vázající RNA * genetika   MeSH
• protoonkogenní proteiny c-myb genetika   MeSH
• protoonkogenní proteiny MeSH
• senioři MeSH
• trans-aktivátory genetika   MeSH
• transkripční faktory NFI genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• EWSR1 protein, human MeSH Prohlížeč
• fúzní onkogenní proteiny * MeSH
• MYB protein, human MeSH Prohlížeč
• MYBL1 protein, human MeSH Prohlížeč
• nádorové biomarkery * MeSH
• NFIB protein, human MeSH Prohlížeč
• protein EWS vázající RNA * MeSH
• protoonkogenní proteiny c-myb MeSH
• protoonkogenní proteiny MeSH
• trans-aktivátory MeSH
• transkripční faktory NFI 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

AIMS: Cutaneous syncytial myoepithelioma (CSM) is a rare myoepithelioma variant of skin, characterized by intradermal syncytial growth of spindle cells with a distinct immunophenotype of EMA and S100 positivity and infrequent keratin expression. While CSM was first described as a cutaneous tumor, singular non-cutaneous cases have since been reported in bone. We aimed to investigate the clinicopathological features of this variant across all anatomic sites through a large multi-institutional study. METHODS AND RESULTS: We complied a total of 24 myoepitheliomas with syncytial growth from our files. The tumors occurred in 12 male and 12 female patients (M:F = 1:1), with a median age of 31 years (range, 9-69 years). While the majority of tumors (75%, n = 18) occurred in skin, a significant subset (25%, n = 6) arose in non-cutaneous sites, including bone (n = 3), bronchus/trachea (n = 2), and interosseous membrane of tibia/fibula (n = 1). Tumor size ranged from 0.4 to 5.9 cm. Clinical follow-up (7 patients; range 14-202 months; median 56.5 months) showed a single local recurrence 8 years after incomplete skin excision but no metastases; all patients were alive at the time of last follow-up without evidence of disease. Histologically, all tumors were pink at low-power and characterized by a syncytial growth of bland ovoid, spindled, or histiocytoid cells with eosinophilic cytoplasm and prominent perivascular lymphoplasmacytic inflammation. One-third displayed adipocytic metaplasia (8/24). Rare cytologic atypia was seen but was not associated with increased mitotic activity. All tumors expressed S100, SMA, and/or EMA. Keratin expression was absent in most cases. Molecular analysis was performed in 16 cases, all showing EWSR1-rearrangments. In total, 15/15 (100%) harbored an EWSR1::PBX3 fusion, whereas 1 case EWSR1 FISH was the only molecular study performed. CONCLUSION: Syncytial myoepithelioma is a rare but recognizable morphologic variant of myoepithelioma which may have a predilection for skin but also occurs in diverse non-cutaneous sites. Our series provides evidence supporting a reappraisal of the term "cutaneous syncytial myoepithelioma," as 25% of patients in our series presented with non-cutaneous tumors; thus, we propose the term "syncytial myoepithelioma" to aid pathologist recognition and avoidance of potentially confusing terminology when referring to non-cutaneous examples. The behavior of syncytial myoepithelioma, whether it arises in cutaneous or non-cutaneous sites, is indolent and perhaps benign with a small capacity for local recurrence.

• Klíčová slova
• Cutaneous syncytial myoepithelioma, EWSR1 rearrangement, EWSR1::PBX3, Myoepithelioma, Syncytial myoepithelioma,
• MeSH
• dítě MeSH
• dospělí MeSH
• keratiny MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• myoepiteliální nádor * patologie   MeSH
• nádorové biomarkery analýza   MeSH
• nádory glandulární a epitelové * MeSH
• nádory kůže * patologie   MeSH
• senioři MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• keratiny MeSH
• nádorové biomarkery 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

Papillary thyroid carcinoma with desmoid-type fibromatosis or nodular fasciitis-like stroma is an extremely unusual and poorly understood subtype of papillary thyroid cancer. Although prior studies have demonstrated alterations in the Wnt/β-catenin signaling pathway in some of these tumors, controversy still exists regarding the nature of the stromal spindle component. We have studied seven cases of papillary thyroid carcinoma with prominent myofibroblastic stroma, including six men and one woman aged 20-65 years (mean age = 44). All cases displayed areas consistent with conventional papillary thyroid carcinoma embedded in abundant myofibroblastic-like stroma. The myofibroblastic stroma in six cases resembled desmoid-type fibromatosis and in one case it more closely resembled nodular fasciitis. By immunohistochemical staining, the stromal spindle component showed positivity for SMA and low MIB1 proliferation index in all cases, and there was at least patchy strong nuclear positivity for beta-catenin in six/seven cases. Stains for cytokeratin AE1/AE3 and PAX8 were positive in the epithelial elements but negative in the stromal component. Next-generation sequencing was performed on six of seven cases. CTNNB1 gene mutations were identified in six/seven cases. The epithelial component showed BRAF mutations in two cases and an NRAS mutation in one case. The case with fasciitis-like stroma was negative for beta-catenin by sequencing and immunostaining as well as negative for USP6 gene rearrangement. Our findings indicate that papillary thyroid carcinoma with prominent myofibroblastic stroma may represent more than one category of lesions.

• MeSH
• beta-katenin genetika   metabolismus   MeSH
• buňky stromatu metabolismus   patologie   MeSH
• dospělí MeSH
• imunohistochemie MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mutace MeSH
• myofibroblasty metabolismus   patologie   MeSH
• nádorové biomarkery metabolismus   MeSH
• nádory štítné žlázy genetika   metabolismus   patologie   MeSH
• papilární karcinom štítné žlázy genetika   metabolismus   patologie   MeSH
• protoonkogenní proteiny B-Raf genetika   metabolismus   MeSH
• senioři MeSH
• štítná žláza metabolismus   patologie   MeSH
• transkripční faktor PAX8 genetika   metabolismus   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• beta-katenin MeSH
• BRAF protein, human MeSH Prohlížeč
• CTNNB1 protein, human MeSH Prohlížeč
• nádorové biomarkery MeSH
• PAX8 protein, human MeSH Prohlížeč
• protoonkogenní proteiny B-Raf MeSH
• transkripční faktor PAX8 MeSH

We present a 72 years old male with a left nasal cavity (mammary analogue) secretory carcinoma (SC) which exhibited classical morphological features on light microscopical examination, diffuse strong S100 and mammoglobin positivity on immunohistochemistry, and ETV6-NTRK3 gene fusion on next generation sequencing (NGS) analysis. Unusual features of this tumor are expression of p63 and DOG1 on immunohistochemistry and the atypical junction between Exon 4 of the ETV6 gene and Exon 14 of the NTRK3 gene.

• Klíčová slova
• ETV6-NTRK3 fusion protein, human, Immunohistochemistry, Mammary analogue secretory carcinoma, Nasal cavity,
• MeSH
• anoctamin 1 biosyntéza   MeSH
• exony genetika   MeSH
• fúzní onkogenní proteiny genetika   MeSH
• lidé MeSH
• membránové proteiny biosyntéza   MeSH
• nádorové biomarkery analýza   MeSH
• nádorové proteiny biosyntéza   MeSH
• nádory nosu genetika   patologie   MeSH
• nosní dutina patologie   MeSH
• sekreční karcinom mamárního typu genetika   patologie   MeSH
• sekvenční analýza DNA MeSH
• senioři MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• Názvy látek
• ANO1 protein, human MeSH Prohlížeč
• anoctamin 1 MeSH
• CKAP4 protein, human MeSH Prohlížeč
• ETV6-NTRK3 fusion protein, human MeSH Prohlížeč
• fúzní onkogenní proteiny MeSH
• membránové proteiny MeSH
• nádorové biomarkery MeSH
• nádorové proteiny MeSH