A Rare Case of Round Cell Sarcoma with CIC-DUX4 Mutation Mimicking a Phlegmon: Review of Literature

Abstract

Patient: Male, 33-year-old Final Diagnosis: CIC-DUX mutation sarcoma Symptoms: Mass in abdomen Medication:— Clinical Procedure: — Specialty: Oncology • Pathology Objective: Rare disease Background: Undifferentiated small blue round cell sarcomas with CIC-DUX4 translocation differ morphologically and in clinical outcomes from other types of sarcoma. Although classified by the World Health Organization as undifferentiated sarcomas, it is unclear whether these tumors are variants of Ewing’s sarcoma or a distinct entity. This report describes a round cell sarcoma with CIC-DUX4 translocation that presented clinically as a phlegmon. Case Report: A 31-year-old African American man presented with a mass in the right upper abdominal quadrant. Examination at a local hospital suggested an intra-abdominal abscess, and incision and drainage were performed. One week later, he returned with increased pain and bloody drainage from the incision site. Computed tomography showed a complex solid-cystic area measuring 7.8 cm suggesting a large phlegmon/abscess or neoplasm. Histologically, the sarcomatous malignancy was cellular, multinodular, and necrotic, with cells having round-ovoid to spindled nuclei and variable amounts of pale cytoplasm. Immunohistochemically, the mass was focally positive for CD99, but much less positive than an Ewing sarcoma. The mass also showed diffuse nuclear positivity for WT-1 and ETV4, but was negative for desmin. Fluorescence in-situ hybridization showed positivity for CIC-DUX4 gene fusion, resulting in a final diagnosis of round cell sarcoma with CIC-DUX4 translocation. The patient has completed 14 cycles of chemotherapy with no evidence of metastasis or local recurrence. Conclusions: A round cell sarcoma with CIC-DUX4 translocation can present clinically as a phlegmon with pleomorphic morphology. Early tumor identification by molecular analysis and early initiation of treatment can improve patient prognosis.

A case report of CIC–DUX4 fusion-positive sarcoma in the pelvic cavity with targeted next-generation sequencing results

“…The manifestations are usually not special, mostly occasionally discovery of mass. However, some unique manifestations are also reported, such as mimicking a phlegmon ( 27 ), cardiac tamponade ( 31 ), vaginal bleeding ( 28 ), and massive ascites in this report, which are caused by the tumor invasion of particular organs. The most common metastasis organ of CDS is the lung, followed by the brain and liver.…”

“…Pathologic mitoses and geographic necrosis are easy to see. Focal myxoid matrix ( 1 , 3 , 7 – 9 , 11 , 13 , 14 , 18 , 25 , 26 , 30 ) and spindle tumor cells ( 3 , 8 – 11 , 14 , 18 , 19 , 21 , 27 ) are also reported in some studies. Other less common morphologies include rhabdoid appearance or plasmacytoid appearance ( 3 , 9 , 12 , 18 , 19 , 25 , 32 ), epithelioid ( 18 , 32 ), formation of microcystic spaces or pseudoacinar arrangements ( 8 , 9 , 15 , 21 , 23 , 32 ), or single cell cords ( 13 ).…”

Patterns of care and outcome of CIC‐rearranged sarcoma patients: A nationwide study of the French sarcoma group

“…Furthermore, the literature analysis reported several cases of good response to chemotherapy according to standard protocols applied to EwS. 19 , 20 Depending on the initial therapeutic strategy, two groups of CRS were evaluated in the study: those treated as EwS and those treated as HG‐STS. There was no statistical difference in mOS and mRFS between both cohorts.…”

“…However, our study shows that multi‐agent regimens can achieved a good response rate (up to 54%), even though duration of response remains limited. Furthermore, the literature analysis reported several cases of good response to chemotherapy according to standard protocols applied to EwS 19,20 . Depending on the initial therapeutic strategy, two groups of CRS were evaluated in the study: those treated as EwS and those treated as HG‐STS.…”

Chromosome Translocation t(10;19)(q26;q13) in a CIC-sarcoma

“…The majority of reported CIC-rearranged tumors were detected using various types of PCR amplifications together with Sanger sequencing, high throughput sequencing, and fluorescence in situ hybridization techniques (5, 6, 29-31, 33-35, 37-41). The detection of CIC::DUX4 chimera has become crucial in establishing a correct diagnosis for tumors that are otherwise difficult to classify (42,43).…”