title: Primary paranasal sinus clear cell carcinoma with EWSR1-ATF1 fusion: report of 2 molecularly confirmed cases exhibiting unique histopathology.
abstract: Hyalinizing clear cell carcinoma (HCCC) is a rare low-grade tumor of the salivary glands made up of clear cells that form cords and nests in hyalinized stroma. To date, primary HCCCs of the paranasal sinus have not been described. This article presents 2 cases of HCCC of the maxillary sinus with unusual glandular formation and lymphoplasmacytic stroma in case 1 and a characteristic solid nest pattern and fibrocellular and hyalinized stroma in case 2. Immunohistochemical studies excluded myoepithelial origin and sinonasal renal cell-like adenocarcinomas. Negativity for p63 and p40 in case 1 ruled out a squamous cell origin. Both cases showed a rearranged EWSR1 gene. Reverse-transcription polymerase chain reaction detected EWSR1-ATF1 fusion gene transcripts, and Sanger sequencing confirmed an EWSR1 exon 11 fused in-frame to ATF exon 3.
authors.affiliation: Department of Anatomic Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Niao-Sung, Kaohsiung 833, Taiwan.
authors.forename: Jui
authors.initials: J
authors.lastname: Lan
authors.affiliation: Department of Anatomic Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Niao-Sung, Kaohsiung 833, Taiwan. Electronic address: shuang@cgmh.org.tw.
authors.forename: Shun Chen
authors.initials: SC
authors.lastname: Huang
authors.affiliation: Department of Pathology, St. Martin De Porres Hospital, Chiayi City 600, Taiwan.
authors.forename: Yi-Hsien
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Niao-Sung, Kaohsiung 833, Taiwan.
authors.forename: Wei-Chih
authors.initials: WC
authors.lastname: Chen
authors.affiliation: Department of Pathology, Taiwan Adventist Hospital, Songshan District, Taipei City 10556, Taiwan.
authors.forename: Ying-Tai
authors.initials: YT
authors.lastname: Jin
authors.affiliation: Department of Otolaryngology, St. Martin De Porres Hospital, Chiayi City 600, Taiwan.
authors.forename: Ying-Chou
authors.initials: YC
authors.lastname: Lu
authors.affiliation: Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Niao-Sung, Kaohsiung 833, Taiwan.
authors.forename: Chih-Yen
authors.initials: CY
authors.lastname: Chien
authors.affiliation: Department of Anatomic Pathology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University, College of Medicine, Niao-Sung, Kaohsiung 833, Taiwan.
authors.forename: Hsuan-Ying
authors.initials: HY
authors.lastname: Huang
mesh_terms: D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics*; D001706:Biopsy; D002277:Carcinoma / Q000737:chemistry / Q000235:genetics* / Q000473:pathology / Q000628:therapy; D004724:Endoscopy; D005091:Exons; D050939:Gene Fusion; D020022:Genetic Predisposition to Disease; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008444:Maxillary Sinus Neoplasms / Q000737:chemistry / Q000235:genetics* / Q000473:pathology / Q000628:therapy; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D010641:Phenotype; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017154:Stromal Cells / Q000737:chemistry / Q000473:pathology; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; C560860:EWSR1-ATF1 fusion protein, human; D015514:Oncogene Proteins, Fusion
keywords: EWSR1 FISH assay; EWSR1-ATF1; Hyalinizing clear cell carcinoma; Minor salivary gland; Nasal sinus