title: A t (11; 22) (p13; q12) EWS-WT 1 positive desmoplastic small round cell tumor of the maxilla: an unusual case indicating the role of molecular diagnosis in round cell sarcomas.
abstract: A desmoplastic small round cell tumor (DSRCT) is an uncommon tumor characterized by polyphenotypic expression and a specific reciprocal translocation t (11; 22) (p13; q12). It has been rarely identified in the head and neck region. Herein, we describe a DSRCT in the maxilla of a young man, who was initially diagnosed with a primitive neuroectodermal tumor (PNET), based on histopathological appearance of a round cell tumor, with MIC2 and -FLI-1 positivity, on immunohistochemistry (IHC). Diagnosis of a DSRCT was confirmed on molecular analysis with positive -RT-PCR and sequencing results for EWS-WT1 transcript and negativity for EWS-FL1. The case is presented to highlight the value of molecular diagnosis in round cell sarcomas at uncommon sites, especially when similar IHC markers can be expressed in a PNET and a DSRCT. An exact diagnosis of a round cell sarcoma has a therapeutic relevance.
authors.affiliation: Department of Pathology, Tata Memorial Center, Dr. E.B. Road, Parel, Mumbai, India. rekhi.bharat@gmail.com
authors.forename: B
authors.initials: B
authors.lastname: Rekhi
authors.forename: R
authors.initials: R
authors.lastname: Basak
authors.forename: S B
authors.initials: SB
authors.lastname: Desai
authors.forename: N A
authors.initials: NA
authors.lastname: Jambhekar
mesh_terms: D000328:Adult; D000970:Antineoplastic Agents / Q000008:administration & dosage; D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008441:Maxillary Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy; D008969:Molecular Sequence Data; D018242:Neuroectodermal Tumors, Primitive / Q000175:diagnosis* / Q000235:genetics; D015514:Oncogene Proteins, Fusion / Q000032:analysis / Q000235:genetics*; D018228:Sarcoma, Small Cell / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy; D014178:Translocation, Genetic
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; C106032:EWS1-WT1 fusion protein, human; D015514:Oncogene Proteins, Fusion