Unusual association of polysplenia syndrome with abdominal teratoma.

Report of a hitherto unreported association of polysplenia, teratoma and eventration of diaphragm.

INTRODUCTION

Spleen is a mesodermal derivate which first appears as a condensation of mesenchymal cells inside the dorsal mesogastrium in the fifth embryonic week.[1] Polysplenia is an anomaly in which spleen is formed by two or more splenuncules. It may either be an isolated anomaly or a component of a syndrome called polysplenia syndrome or bilateral left-sidedness.[2] Polysplenia syndrome is presence of two or more spleens of identical sizes in a person associated with various organ anomalies.[3-5] The various anomalies that have been described in association with polysplenia syndrome include cardiopulmonary, genitourinary, gastrointestinal and central nervous system anomalies, situs inversus, duplicated inferior vena cava, azygos and hemiazygos continuation, pancreatic and hepatobiliary anomalies.[67] In the English literature, there is no reported association of polysplenia with any neoplastic lesion or abnormalities of diaphragm.

This report describes a case of intra-abdominal teratoma associated with polysplenia and eventration of ipsilateral hemidiaphragm.

CASE REPORT

A five-month-old male child presented with respiratory distress for two months. On chest skiagram, there was presence of a well-defined, homogenous opacity in right lower lung zone without any evidence of air bronchogram or breakdown. The possibilities of segmental collapse of the right lower lobe versus eventration of diaphragm was made and contrast enhanced computerized tomography (CECT) was advised. The CECT chest and abdomen [Figures 1–3] of the child revealed a large (7.8 × 6 × 4.8 cm), heterogenous mass lesion in right lower hemithorax in paravertebral location showing areas of fat density, calcification and cystic changes. The anterior portion of the right hemidiaphragm was deficient with associated intrathoracic herniation of the antero-superior portion of the liver. There was an abnormal vessel arising from the right branch of the portal vein entering into the mass and an abnormal vein was seen draining the mass into the intrahepatic IVC. In addition, there was presence of multiple (3 in no.) splenunculi in the normal location of the spleen. CT diagnosis of polysplenia and eventration of right hemidiaphragm with teratoma was made in view of areas of fat and calcification within the mass. The patient was operated and the histopathology of the surgical specimen was confirmatory of mature teratoma.

Figure 1

Axial CECT section of the upper abdomen showing multiple splenunculi (arrow) in the normal location of the spleen

Figure 3

Axial CECT section showing heterogenous mass in right hemithorax (arrow) with areas of fat density and foci of calcification. Portion of liver is also seen herniated into the thorax

Coronal reformatted CT image of the patient showing polysplenia with a large, heterogenous mass in right lower hemithorax (arrow) with cystic and fatty attenuation areas

DISCUSSION

Polysplenia describes a condition with presence of two or more spleens. Most of the patients with polysplenia syndrome die before the onset of five years of age because of the presence of associated congenital anomalies.[8] In our case, there was isolated polysplenia without any associated abnormalities in the cardiovascular, genitourinary, gastrointestinal or hepatobiliary system. A teratoma was found in the right lower hemithorax with ipsilateral diaphragmatic eventration. An abnormal branch of the portal vein was supplying the tumor indicating its primary intra-abdominal location which herniated into the thorax through the diaphragmatic defect. There was evidence of venous drainage into the systemic circulation through the intrahepatic IVC. Search in the PubMed and other electronic database did not reveal any report describing the presence of teratoma and diaphragmatic eventration without any associated systemic abnormalities in a patient with polysplenia. Preduodenal portal vein is found in association with polysplenia syndrome.[6] There is one case report describing abnormal branching pattern of the portal vein.[9] In our case, an abnormal portal venous branch was seen arising from the right branch which was supplying the tumor with the venous drainage into the systemic circulation.