Case No. :	22
Month :	October
Year :	2000
Contributor :	Dr. Joshita Singh

Clinical Profile | Radiological Findings | Discussion

Clinical Profile:
A four- year- old girl presented with complaints of failure to thrive . There was history of occasional vomiting. The patient had no bowel or bladder complaints. On examination, she had a firm, 6 x 8 cm mass in the epigastrium and left hypochondriac region which moved with respiration.

Serum AFP and beta HCG levels were within normal range

The hemogram was unremarkable.

Radiological Findings

An abdominal radiograph revealed faint calcification in the left tenth and eleventh intercostal space and a soft tissue mass in the left hypochondriac and lumbar region.

An ultrasound of the abdomen (Fig 1,2), excretory urogram (Fig3,4) and CT scan the abdomen (Fig 5,6) were obtained.

 

The ultrasonogram reveals a large, complex, echogenic lesion in relation to the superior pole of the left kidney displacing the kidney inferolaterally. It had an anechoic component measuring 2 x 1.5 x 1.2 cm with a solid component within it. The mass was seen to cross the midline and stretch the superior mesenteric artery. Calcification was noted within the mass.

The intravenous urogram the left kidney to be pushed inferolaterally with slight displacement and compression of the proximal left ureter by an adrenal fossa mass.

 

The CT scan shows a 8 x 7 x 6 cm mass, predominantly of fat density with foci of calcification (bone) within, occupying nearly the entire abdomen, displacing the left kidney inferiorly .The liver, spleen, pancreas, both kidneys and adrenals are normal.

With the above imaging findings a diagnosis of retroperitoneal teratoma was made.

The patient was taken up for surgery. However the large, grey coloured firm to hard

15 x 12 x 5 cm retroperitoneal tumor was found to involve the porta hepatis, superior mesentric vessels and the duodeno-jejunal flexure. As the tumor was inoperable , biopsy was done . The frozen section was suggestive of benign adipose tissue with myxoid foci, the possibility of lipoblastoma was raised.

Differential Diagnosis and Discussion :

Retroperitoneal neoplasms are a diverse group of tumors .They are usually large at presentation as they must reach a large size to cause compression of adjacent structures to become symptomatic. Tumors with adipose tissue as in this case, with the child having presented at the age of three, would include the following :

1. Teratoma
2. Lipoblastoma

Liposarcomas are typically not found in childhood. The fact that the frozen section raised a possibility of lipoblastoma could be due to selective sampling. In such a case where the whole tumor can not be removed imaging plays an important role. It guides the surgeon to biopsy from the right place so that a histopathological diagnosis can be reached and allows the histopathologist to consider other differentials and demand an adequate sampling.

The term teratoma was coined by Rudolph Virchow in 1869 and was defined by the histologic demonstration of origin from the three embryonic layers-ectoderm, mesoderm, and endoderm. Teratomas can be differentiated from other fat containing neoplasms by the presence of fluid density, a fat-fluid level, and calcifications. Teratomas can occur within the brain, mouth, neck, thoracic cavity, abdominal cavity, in the gonads and in the retroperitoneal space. Teratomas have not been reported in the limbs. Lipoblastomas on the other hand, occur most commonly in the subcutaneous tissues of the limbs or trunk. The incidence of retroperitoneal teratomas is equal in both the sexes. They occur more commonly on the left than the right. Between 6-10% of retroperitoneal teratomas are malignant. The treatment for benign teratomas is excision and that for malignant teratomas is excision followed by aggressive post-operative chemotherapy.

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