Malignant rhabdoid tumor of liver
A 6-month-old boy presented with a 15 days history of abdominal distension, irritability and reluctance to feed. There was no vomiting, constipation or jaundice. On physical examination, the child was febrile with normal vitals; abdomen was distended with hepatomegaly, no lump was felt. Ultrasound of the abdomen revealed the presence of hyperechoic lesions in the liver. Contrast enhanced computed tomography (CT) scan of the abdomen revealed multiple lesions in the liver (both lobes), which were homogeneously hypodense; had no evidence of calcification [Figure and ]. There was no change in the caliber of the infraceliac abdominal aorta or enlargement of the hepatic artery. Magnetic resonance imaging (MRI) showed that the lesions were hypointense on T1-Weighted (W) and hyperintense on T2-W images [Figure and ]. MIBG (meta-iodobenzylguanadine) scan did not reveal any uptake. A 24 h urinary vanillylmandelic acid was with in normal limits (0.46 mg/g of creatinine); serum homovanillic acid was mildly raised (28.18 mg/g of creatinine); and serum alpha-fetoprotein (αFP) was within normal limits. Fine needle aspiration cytology of the lesion was inconclusive; hence, a wedge biopsy was performed through a minilaparotomy. Macroscopic examination of the wedge showed a stretched out capsule on the exterior aspect with a tan colored tumor within showing areas of necrosis. On microscopic examination of H and E stained sections [] a tumor was seen adjacent to normal liver tissue. The tumor was arranged in nodules with the absence of trabeculae and sinusoids. The tumor cells had large nucleus having prominent nucleoli and moderate to abundant cytoplasm with pink inclusion bodies. The immunohistochemistry revealed positivity for cytokeratin and vimentin while it was negative for glycogen, desmin and chromogranin. Immunocytochemistry for INI-1 was not available. The histology was consistent with MRT of the liver. Patient was started on chemotherapy (carboplatin, etoposide and cyclophosphamide), but died soon after of progressive tumor and massive unrelenting ascites.