Branchioma is an uncommon benign neoplasm with an adult male predominance, typically occurring in the lower neck region. Different names have been used for this entity in the past (ectopic hamartomatous thymoma, branchial anlage mixed tumor, thymic anlage tumor, biphenotypic branchioma), but currently, the term branchioma has been widely accepted. Branchioma is composed of endodermal and mesodermal lineage derivatives, in particular epithelial islands, spindle cells, and mature adipose tissue without preexistent thymic tissue or evidence of thymic differentiation. Twenty-three branchiomas were evaluated morphologically. Eighteen cases with sufficient tissue were assessed by immunohistochemistry, next-generation sequencing (NGS) using the Illumina Oncology TS500 panel, and fluorescence in situ hybridization (FISH) using an RB1 dual-color probe. All cases showed a biphasic morphology of epithelial and spindle cells with intermingled fatty tissue. Carcinoma arising in branchioma was detected in three cases. The neoplastic cells showed strong AE1/3 immunolabeling (100%), while the spindle cells expressed CD34, p63, and SMA (100%); AR was detected in 40-100% of nuclei (mean, 47%) in 14 cases. Rb1 showed nuclear loss in ≥ 95% of neoplastic cells in 16 cases (89%), while two cases revealed retained expression in 10-20% of tumor cell nuclei. NGS revealed a variable spectrum of likely pathogenic variants (n = 5) or variants of unknown clinical significance (n = 6). Loss of Rb1 was detected by FISH in two cases. Recent developments support branchioma as a true neoplasm, most likely derived from the rudimental embryological structures of endoderm and mesoderm. Frequent Rb1 loss by immunohistochemistry and heterozygous deletion by FISH is a real pitfall and potential confusion with other Rb1-deficient head and neck neoplasms (i.e., spindle cell lipoma), especially in small biopsy specimens.
- MeSH
- branchiom * patologie MeSH
- dospělí MeSH
- hybridizace in situ fluorescenční MeSH
- lidé MeSH
- molekulární biologie MeSH
- nádory brzlíku * MeSH
- nádory glandulární a epitelové * MeSH
- nádory měkkých tkání * patologie MeSH
- nádory sítnice * MeSH
- retinoblastom * genetika patologie MeSH
- thymom * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Branchioma (previously called ectopic hamartomatous thymoma, branchial anlage mixed tumor, or thymic anlage tumor) is a rare lower neck lesion with an adult male predominance and an uncertain histogenesis. Except for 4 cases, all branchiomas described in the literature were benign. Recently, HRAS mutation was detected in one case, but still little is known about the molecular genetic background of this rare entity. We herein report the histological, immunohistochemical, and molecular genetic analysis of a branchioma with a nested/organoid (neuroendocrine-like) morphology in a 78-year-old man. Histology revealed classical branchioma areas merging with nested/organoid cellular component lacking conventional features of malignancy. Immunohistochemistry was positive for high-molecular-weight cytokeratins. CD34 was expressed in the spindle cell component. Moreover, the tumor cells showed near-complete loss of retinoblastoma (RB1) expression (<1% of cells positive). All neuroendocrine markers (synaptophysin, chromogranin, and INSM1) were negative. Next-generation sequencing (TSO500 Panel) revealed 5 pathogenic/likely pathogenic mutations including 1 mutation in KRAS and 2 different mutations in each of MSH6 and PTEN. FISH and DNA sequencing were negative for RB1 gene alterations. To our knowledge, this is the first report of a branchioma showing misleading nested/organoid morphology and the first report on Rb1 immunodeficiency in this entity, in addition to multiple gene mutations revealed by NGS.
- MeSH
- branchiom * patologie MeSH
- lidé MeSH
- nádory měkkých tkání * MeSH
- nádory sítnice * MeSH
- organoidy patologie MeSH
- represorové proteiny MeSH
- retinoblastom * genetika patologie MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
The knowledge of clinical features and, particularly, histopathological spectrum of EWSR1-PATZ1-rearranged spindle and round cell sarcomas (EPS) remains limited. For this reason, we report the largest clinicopathological study of EPS to date. Nine cases were collected, consisting of four males and five females ranging in age from 10 to 81 years (average: 49 years). Five tumors occurred in abdominal wall soft tissues, three in the thorax, and one in the back of the neck. Tumor sizes ranged from 2.5 to 18 cm (average 6.6 cm). Five patients had follow-up with an average of 38 months (range: 18-60 months). Two patients had no recurrence or metastasis 19 months after diagnosis. Four patients developed multifocal pleural or pulmonary metastasis and were treated variably by surgery, radiotherapy, and chemotherapy. The latter seemed to have little to no clinical benefit. One of the four patients was free of disease 60 months after diagnosis, two patients were alive with disease at 18 and 60 months, respectively. Morphologically, low, intermediate, and high-grade sarcomas composed of a variable mixture of spindled, ovoid, epithelioid, and round cells were seen. The architectural and stromal features also varied, resulting in a broad morphologic spectrum. Immunohistochemically, the following markers were most consistently expressed: S100-protein (7/9 cases), GFAP (7/8), MyoD1 (8/9), Pax-7 (4/5), desmin (7/9), and AE1/3 (4/9). By next-generation sequencing, all cases revealed EWSR1-PATZ1 gene fusion. In addition, 3/6 cases tested harbored CDKN2A deletion, while CDKN2B deletion and TP53 mutation were detected in one case each. Our findings confirm that EPS is a clinicopathologic entity, albeit with a broad morphologic spectrum. The uneventful outcome in some of our cases indicates that a subset of EPS might follow a more indolent clinical course than previously appreciated. Additional studies are needed to validate whether any morphological and/or molecular attributes have a prognostic impact.
- MeSH
- dítě MeSH
- dospělí MeSH
- fenotyp MeSH
- fúze genů MeSH
- genetická predispozice k nemoci MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádorové biomarkery analýza genetika MeSH
- nádory měkkých tkání chemie genetika patologie chirurgie MeSH
- protein EWS vázající RNA genetika MeSH
- represorové proteiny genetika MeSH
- sarkom chemie genetika patologie chirurgie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- transkripční faktory Krüppel-like genetika MeSH
- výsledek terapie MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
- Spojené státy americké MeSH
Popisován je případ padesátidevítileté ženy s tumorózní expanzí převážně v měkkých tkáních oblasti C5/6 krční páteře s destrukcí obratlového oblouku C6 a útlakem durálního vaku. Konzultující patolog favorizoval diagnózu primárního kostního tumoru typu obrovskobuněčného kostního nádoru. Mikroskopický obraz odpovídal obrovskobuněčné lézi s převažující pravidelnou mononukleární stromální složkou, nerovnoměrně rozloženými vícejadernými elementy napodobujícími osteoklasty a mapovitými xantogranulomatózními infiltráty, včetně všudypřítomného drobně hrudkovitého hemosiderinového pigmentu. Nečekané pak byly doprovodné oblasti pokročilé hyalinní fibrózy společně s nezvyklými a matoucími pseudoalveolárními formacemi, které zastíraly původní charakteristický projev. Nádor se šířil neohraničeně do okolní příčně pruhované svaloviny, známky produkce extracelulární matrix či struktury původního skeletu nebyly nalezeny. Imunohistochemické vyšetření s markery p63, SATB2, desmin, EMA, clusterin a S100 protein bylo kompletně negativní; metodou FISH nebyl prokázán zlom genu CSF1. Proces byl definitivně hodnocen jako difúzní obrovskobuněčný tumor šlachové pochvy.
Presented is a case of 59-year-old woman with longstanding neck pain who has been promptly operated for spinal cord compression. Imaging studies disclosed ill-defined cervical paravertebral soft tissue mass at the level of vertebra C5/6 abutting left-sided intervertebral joint and destroying neighboring both vertebral arch and processus spinosus. Submitted specimen was interpreted as a possible metastatic skeletal process by clinicians and referring pathologist favored diagnosis of giant cell tumor/osteoclastoma of the bone. Microscopic features were consistent with giant cell lesion where uniform mononuclear mosaic stromal component dominated the unevenly distributed loose clusters of osteoclast-like giant cells frequently imparting appearance of peculiar pseudoalveolar spaces. Additionally, alternating geographic xanthomatous and densely hyalinized/ osteoid-like zones with speckled, coarsely granular haemosiderin pigment completed the variegated structural composition. The tumor infiltrated adjacent striated muscles; either original bone structures and/or extracellular matrix deposits were not identified. Immunohistochemical stains with p63, SATB2, desmin, EMA, clusterin and S100protein turned out to be completely negative. FISH analysis revealed no rearrangement of CSF1 gene. The diagnosis of the diffuse tenosynovial giant cell tumor was rendered.
- MeSH
- diferenciální diagnóza MeSH
- imunohistochemie metody MeSH
- krční obratle * patofyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory kostí diagnóza patologie MeSH
- nádory obrovskobuněčné * diagnóza patologie MeSH
- páteř patofyziologie MeSH
- tenosynovitida komplikace patologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
- MeSH
- amplifikace genu MeSH
- dospělí MeSH
- geny erbB-2 MeSH
- humanizované monoklonální protilátky * farmakokinetika terapeutické užití MeSH
- hybridizace in situ fluorescenční MeSH
- lidé MeSH
- molekulární epidemiologie metody MeSH
- nádory prsu * farmakoterapie MeSH
- plošný screening MeSH
- receptor erbB-2 * antagonisté a inhibitory MeSH
- sekvenční analýza * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- multicentrická studie MeSH