Primary Malignant Rhabdoid Tumor of the Liver in a 5-Month-Old Female Who Presented with Abdominal Distension.

BACKGROUND Malignant rhabdoid tumors are rare and aggressive pediatric tumors that usually arise in the kidney and have a characteristic appearance on histology. Extrarenal malignant rhabdoid tumors originating in the liver are extremely rare. This report is of a 5-month-old girl who presented with a rapidly enlarging abdominal mass due to a malignant rhabdoid tumor of the liver. CASE REPORT A 5-month-old female patient with no known medical history had been experiencing increasing abdomen distention and less overall activity for 1 month, according to her parents. Abdominal ultrasonography was used for diagnostic purposes, and the results showed the presence of a mass with a solid and cystic appearance in the upper left quadrant of the abdomen. The patient was transferred to a tertiary care hospital for further investigations. The laboratory test results indicated a hemoglobin level of 8.2 g/dL, and the liver function tests were within the reference range. However, the serum tumor marker alpha-fetoprotein level was 1310 ng/mL, while the b-human chorionic gonadotropin was within range. Computed tomography detected a nonspecific heterogeneous mass of the liver. Histopathology revealed discohesive cells with rich eosinophilic cytoplasm, eccentric nuclei, and large central nucleoli (rhabdoid appearance). Immunohistochemistry showed negative integrase interactor 1 protein expression. The diagnosis was a primary malignant rhabdoid tumor located in the liver. CONCLUSIONS This report shows the importance of combined diagnostic imaging and histopathology analysis to confirm the diagnosis of rare pediatric tumors, including malignant rhabdoid tumor, to ensure early diagnosis and appropriate treatment.