# Rhabdomyosarcoma of the Biliary Tract in Children: Analysis of Single Center Experience

## TL;DR

This paper presents a case study of children with a rare type of cancer in the bile ducts and discusses treatment strategies and outcomes.

## Contribution

The study contributes a single-center analysis of treatment approaches and outcomes for biliary tract rhabdomyosarcoma in children.

## Key findings

- Six out of eight patients survived with no evidence of disease after treatment.
- Treatment strategies included biopsy, chemotherapy, surgery, and radiotherapy.
- Two patients died from the disease within three years of diagnosis.

## Abstract

Rhabdomyosarcoma of the extrahepatic and intrahepatic bile ducts is a rare location in children, and it poses a significant challenge for both oncologists and surgeons. Key elements of treatment where there are no clear guidelines include surgical treatment of RMS of the bile ducts, chemotherapy and radiotherapy. The authors wish to share the experience of a highly specialized center that has access to a wide range of therapeutic and treatment options, including the management approach and the outcomes achieved. We review cases treated at our center, discuss treatment approaches and outcomes and compare results with the existing literature and guidelines.

Rhabdomyosarcoma (RMS) of the biliary tract is a rare tumor in children, constituting 0.5–0.8% of all pediatric RMS. Still, it is the most common malignancy in this location in children. Due to its rarity and location, it may cause diagnostic and treatment difficulties. Above all, there are no therapeutic guidelines specific for this tumor location. The aim of the study was to present an analysis of our experience with the treatment of children with biliary tract rhabdomyosarcoma (RMS) and discuss clinical recommendations for this specific location published in the literature. A retrospective analysis of medical records of eight children with biliary tree RMS treated in one center between 1996–2022 was performed. Records of eight children, five boys and three girls aged 2 yrs 6 mo to 16 yrs 9 mo (median—6 yrs) were analyzed. All patients presented with jaundice as the first symptom. In two patients, initial diagnosis of a tumor was established. For the remaining six, the primary diagnoses were as follows: choledochal cyst—one, malformation of the biliary ducts—one, choledocholithiasis—one, cholangitis—three. In four patients, the extrahepatic bile ducts were involved; in four patients, both the intrahepatic and extrahepatic bile ducts were involved. Embryonal RMS was diagnosed in seven patients (three botryoides type). Alveolar RMS was found in one patient. Biopsy (three surgical, four during endoscopic retrograde cholangiopancreatography (ERCP)) was performed in seven patients. One child underwent primary partial tumor resection (R2). Seven patients received neoadjuvant chemotherapy, followed by delayed resection in five, including liver transplantation in one (five were R0). Two patients did not undergo surgery. Radiotherapy was administered in four patients (two in first-line treatment, two at relapse/progression). Six patients (75%) are alive with no evidence of disease, with follow-up ranging from 1.2 yrs to 27 yrs (median 11 yrs. and 4 mo.). Two patients died from disease, 2 y 9 mo and 3 y 7 mo from diagnosis. Children presenting with obstructive jaundice should be evaluated for biliary tract RMS. The treatment strategy should include biopsy and preoperative chemotherapy, followed by tumor resection and radiotherapy for residual disease and in case of relapse.