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.
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.
Rekhi
B
B
Department of Pathology, Tata Memorial Center, Dr. E.B. Road, Parel, Mumbai, India. rekhi.bharat@gmail.com
Basak
R
R
Desai
S B
SB
Jambhekar
N A
NA
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
D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; C106032:EWS1-WT1 fusion protein, human; D015514:Oncogene Proteins, Fusion