Biliary rhabdomyosarcoma

Review on Pediatric Malignant Focal Liver Lesions with Imaging Evaluation: Part II

Malignant focal liver lesions (FLLs) represent various kinds of epithelial and mesenchymal tumors. In pediatric patients, the understanding of pediatric liver diseases and associated imaging manifestations is essential for making accurate diagnosis and differential diagnosis. This paper will discuss the latest knowledge of the common pediatric malignant FLLs, including undifferentiated embryonal sarcoma, rhabdomyosarcoma, epithelioid hemangioendothelioma, angiosarcoma, and malignant rhabdoid tumor. Medical imaging features are not only helpful for clinical diagnosis, but can also be useful in the evaluation and follow-up of pre- and post-treatment. The future perspectives of contrast-enhanced ultrasound (CEUS) enhancement patterns of FLLs in pediatric patients are also mentioned.

Embryonal Rhabdomyosarcoma of the Biliary Tree as a Differential in a Paediatric Patient Presenting with Biliary Dilatation: Not Always a Choledochal Cyst

Rhabdomyosarcoma is a soft tissue malignant musculoskeletal tumour and is the most prevalent soft-tissue sarcoma in the paediatric population. Although, Embryonal RMS of the biliary tree is a rare entity, however, it is the most common cause of paediatric malignant obstructive jaundice. We present a 4-year-old child who had symptoms of obstructive jaundice and palpable liver. The non-contrast magnetic resonance imaging and magnetic resonance cholangiopancreatography (MRCP) features were consistent with choledochal cyst. However, contrast enhanced computed tomography and PET CT images revealed biliary RMS as the differential diagnosis. Percutaneous biopsy followed by histopathology confirmed the diagnosis of embryonal biliary RMS. Since embryonal rhabdomyosarcoma is uncommonly recorded in the literature and can mimic the appearance of a choledochal cyst, this case report emphasises the necessity of keeping embryonal RMS as a differential in paediatric cases of obstructive jaundice.

MRI of Rhabdomyosarcoma and Other Soft-Tissue Sarcomas in Children

Soft-tissue sarcomas in children comprise a heterogeneous group of entities with variable manifestation depending on the age of the patient and the location of the tumor. MRI is the modality of choice for evaluating musculoskeletal soft-tissue tumors and plays a paramount role in both initial diagnosis and assessment of tumor response during and after treatment. Conventional MRI sequences, such as T1- and T2-weighted imaging, offer morphologic information, which is important for localizing the lesion and describing anatomic relationships but not accurate for determining its malignant or benign nature and may be limited in differentiating tumor response from therapy-related changes. Advanced multiparametric MRI offers further functional information that can help with these tasks by using different imaging sequences and biomarkers. The authors present the role of MRI in rhabdomyosarcoma and other soft-tissue sarcomas in children, emphasizing a multiparametric approach with focus on the utility and potential added value of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced MRI in characterization and staging, determination of pretreatment extent, and evaluation of tumor response and recurrence after treatment. ^©RSNA, 2020.

Outcome of localized liver-bile duct rhabdomyosarcoma according to local therapy: A report from the European Paediatric Soft-Tissue Sarcoma Study Group (EpSSG)-RMS 2005 study

OBJECTIVES

To evaluate the impact of local therapies on the outcome of patients with liver-bile duct rhabdomyosarcoma (LBDRMS).

METHODS

Data of 30 patients included in the EpSSG-RMS 2005 study were analyzed.

RESULTS

The median age at diagnosis was 3 years (11 months-8 years). All patients had non-alveolar histology. Fifteen patients had a tumor > 5 cm and six had enlarged regional lymph nodes on imaging. Eight patients (27%) had primary surgery (1 R0). Six of them received external beam radiotherapy (EBRT). All are in first complete remission (CR1) except one (R1, EBRT⁺ , local relapse, death). Six patients (20%) received EBRT without surgery: one had local relapse and died. Sixteen patients (53%) underwent delayed surgery, with 12 achieving R0 margins, which were higher than those in the primary surgery group (P = 0.003). Three patients with R0 margins received EBRT; one had a metastatic relapse and died. Nine patients with R0 resection did not receive EBRT, three relapsed locally (two deaths). Four R1 patients received additional EBRT without relapses. Local relapse occurred in two among 19 patients with EBRT and three among 11 without EBRT (P = 0.326). At a median follow-up of 61 months (48-84 months), five patients died; all had a tumor size > 5 cm (P = 0.01). The five-year overall survival was 85% (95% CI, 65-94), and event-free survival was 76% (95% CI, 54-89).

CONCLUSION

This analysis did not show any significant difference in outcome between irradiated and nonirradiated patients. Local relapse in LBDRMS is related to initial tumor size and is often fatal.

Embryonal rhabdomyosarcoma of the biliary tree in a paediatric patient – A rare cause of obstructive jaundice

Rhabdomyosarcoma (RMS) is the most common soft-tissue sarcoma in the paediatric age group, ranking fourth in frequency after central nervous system tumours, neuroblastomas and nephroblastomas. Embryonal RMS of the biliary tree is considered a rare entity, with the most common clinical presentation being that of obstructive jaundice. We present the case of a 4-year-old boy who presented with hepatomegaly and obstructive jaundice. Biochemically, there was evidence of elevated ductal enzymes with conjugated hyperbilirubinaemia. The magnetic resonance imaging (MRI) features were consistent with a biliary RMS with the differential diagnosis of a choledochal cyst initially included based on the computed tomography images. The diagnosis of embryonal biliary RMS was later confirmed on histology. This case illustrates the importance of considering malignant aetiologies in paediatric cases of obstructive jaundice, as this entity is infrequently described in the literature and may mimic the appearance of a choledochal cyst. The demonstration of enhancement of intraductal material within the biliary tree on MRI and the presence of arterial waveforms within the intraductal mass on ultrasound assists in the differentiation between biliary RMS and a choledochal cyst.

Biliary tract rhabdomyosarcoma: a report from the Soft Tissue Sarcoma Committee of the Associazione Italiana Ematologia Oncologia Pediatrica

Introduction:

Rhabdomyosarcoma is a soft tissue malignant musculoskeletal tumor frequent in children. Biliary duct localization is extremely rare, but it is the most common cause of malignant obstructive jaundice in pediatric patients.

Methods:

This report describes a series of 10 patients under 18 years of age with biliary tract rhabdomyosarcoma who were enrolled, from 1979 to 2004, in 3 consecutive Italian pediatric cooperative protocols that had been drawn up by the Soft Tissue Sarcoma Committee of the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP).

Results:

Considering initial and delayed surgery, tumor resection was achieved in 7 cases, 3 complete with free margins (2 liver transplants) and 4 with microscopic residual disease. Chemotherapy was given to all patients and radiotherapy to 3. At present, 5 patients survive in complete remission 90-200 months after diagnosis while 4 died of disease progression or relapse and 1 of liver transplant-related complications.

Conclusions:

Better outcomes in this series were associated with the feasibility of conservative surgery due to the favorable location of the tumor, in particular in the common bile duct. Chemotherapy and radiotherapy might obviate the need for demolitive surgery or liver transplant, which were linked to worse outcomes in our series.