Differentiating Hepatic Desmoplastic Small Round Cell Tumor from Hydatidosis in a School-Aged Boy: The Role of Contrast-Enhanced and Interventional Ultrasound

Zehui Gou ¹ Hualin Yan ¹ Boyang Yu ¹ Xiaolong Xie ² Bo Xiang ² Juxian Liu ^1* Yan Luo ¹

• ¹ Department of Medical Ultrasound, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
• ² Department of Pediatric Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China

Background: Desmoplastic small round cell tumor (DSRCT) is a rare and highly aggressive malignant neoplasm, typically associated with poor prognosis. It predominantly affects adolescents and young males, with a lower incidence in pediatric populations. Due to its rarity, our understanding of DSRCT remains limited, with only a small number of case reports available. The clinical presentation is often non-specific and varies depending on the extent of tumor invasion. Diagnosis relies primarily on histopathological evaluation through biopsy. Although imaging studies contribute to the diagnostic process, they often lack specificity. Nonetheless, certain imaging features can aid in refining differential diagnoses and assessing disease severity. Moreover, minimally invasive, image-guided tissue sampling plays a critical role in confirming the diagnosis through pathological analysis.Case presentation: A 7-year-old boy presented with abdominal distension and anorexia, without significant abdominal pain, fever, or jaundice. Physical examination revealed abdominal enlargement with hepatosplenomegaly. Laboratory tests showed abnormal liver function (AST 128 U/L, ALP 648 U/L, GGT 885 U/L) and an elevated CA-125 level (170 U/ml). An abdominal CT scan performed at a local hospital identified multiple round, lowdensity lesions in the liver, suggestive of echinococcosis. The patient was initially diagnosed with suspected echinococcosis and started on albendazole; however, his symptoms did not