EMBRYONAL BILIARY RHABDOMYOSARCOMA PRESENTING WITH OBSTRUCTIVE JAUNDICE AND CHOLEDOCHOLITHIASIS

I Wrobel, G May¹, D Sigalet², V Lewis, JD Butzner

Departments of Paediatrics, Medicine¹, Surgery² University of Calgary, Alberta Children's Hospital, Calgary, Alberta

A malignant stricture of the extrahepatic biliary tree is an unusual cause for obstructive jaundice in children. Of the previously reported cases of rhabdomyosarcoma of the biliary tree most were large masses. We present a case of a child with a smaller tumor mass resulting in biliary obstruction.
This 6 y.o. girl presented with obstructive jaundice, pruritus and vague abdominal pain. Laboratory investigations were consistent with cholestasis and abdominal ultrasound revealed a dilated common bile duct to the level of the pancreatic head. At ERCP the papilla was slightly budging. The cholangiogram demonstrated proximal dilation of the common bile duct with a single filling defect suggesting a stone. Sphincterotomy was performed and several small stone fragments were removed. A biliary stent was placed due to presence of narrowing of the distal CBD. Further CT and MRI imaging demonstrated hypodense abnormality 7´14´14 mm within the head of the pancreas. This was initially interpreted as edema or focal pancreatitis. Serial radiological investigations showed no change in the size of the lesion for 5 months and repeated brushings of the common bile duct for cytology were negative. Over the next month, there was a rapid progression to a gelatinous polypoid mass of papilla with proximal extension of the stricture and enlargement of the tumor mass on MRI. Biopsies of the papilla were consistent with an embryonal rhabdomyosarcoma of the common bile duct. The patient has started chemotherapy with vincristine, actinomycin D and cyclophosphamide prior to planned surgical resection. Further treatment with radiation and/or surgical resection will be determined based on response to induction chemotherapy.
CONCLUSIONS: Although primary neoplasms of the biliary tree constitute a very rare cause for cholestasis in children they need to be considered due to the critical location of the tumor. Brushings for cytology may give false negative results necessitating an early biopsy of suspicious lesions. Early diagnosis with a good response of rhabdomyosarcoma to chemotherapy may minimize the extent of surgical intervention necessary and improve the patient outcome.