Desmoplastic small round cell tumor of the liver: diagnosing a rare case on liver biopsy

Abstract

Desmoplastic small round-cell tumors (DSRCT) frequently develop in the retroperitoneum, pelvis, omentum, and mesentery. Here, we present an unusual case of primary DSRCT in the liver. The patient was an 11-year-old boy with multiple solid masses in the liver parenchyma. The tumor in the needle biopsy had a histology revealing a small round cell morphology and desmoplasia. It shows the immunohistochemical features of DSRCT and documentation of EWSR1-WT1 fusion.A potential diagnostic pitfall is exerted when evaluating liver biopsy, in which DSRCT is a great mimicker and may be easily confused with more common liver malignancies of childhood, such as hepatoblastoma, calcifying nested stromal-epithelial tumor, undifferentiated embryonal sarcoma, and other small round cell tumors, as well as the fibrolamellar variant of hepatocellular carcinoma. This distinction is critical because an accurate therapeutic approach requires a correct diagnosis.

Desmoplastic Small Round Cell Tumor: A Case Report

“…DSRCTs were identified and characterized by Gerald and Rosai in 1989 [9]. The mean age of diagnosis is approximately between 19 and 22 years, ranging from 6 to 49 years, with a male predominance of 75% [5,10]. In accordance, the present case was a male in his forties.…”

“…However, Baydar et al reported 11 cases of primary renal DSRCT, of which seven were females and presented with gross haematuria and abdominal pain [3]. The abdominal cavity is the most common site for tumor development [5]. This rare malignant soft tissue tumor is associated with a poor prognosis and extreme aggressiveness.…”

“…The tumor has an incidence rate of 0.0002% to 0.0005%, with a total of about 200 to 500 reported cases. It is more frequently observed among individuals aged 20 to 30, with a median age of onset of 19 years [2,4,5]. DSRCT primarily manifests within the abdominal region, particularly in the retroperitoneum, pelvis, peritoneum, or mesentery.…”

“…In rare instances, it can also affect the kidneys and ovaries. At the time of presentation, nearly all patients exhibit peritoneal metastases, while approximately half of them may present with extra-peritoneal metastases [4,5]. Specific clinical manifestations are generally absent in DSRCT, with common symptoms typically revolving around abdominal or pelvic pain.…”

Case Report: Colon malignant tumor caused by retroperitoneal small round cell undifferentiated sarcoma

“…It is extremely rare in clinical practice, with few reports in the literature, a high misdiagnosis rate, and poor prognosis ( 18 ). Interestingly, recent reports have mainly focused on cases of Ewing sarcoma of the colon/PNET combined with liver metastasis, with an overall cure rate of only 20% for metastatic Ewing sarcoma ( 25 , 26 ). It is noteworthy that the median survival time for small round cell undifferentiated sarcoma is less than 2 years ( 19 , 27 ), and the 5-year survival rate for 57 patients with CIC rearrangement sarcoma was 43%, lower than that of Ewing sarcoma ( 28 ).…”