Gallbladder and extrahepatic biliary tract
A rare aggressive malignant mesenchymal neoplasm arising from skeletal muscle. It usually occurs in children and young adults. Only a small percentage of tumors arise in the skeletal muscle of the extremities. The majority arise in other anatomical sites.
In young children, embryonal (botryoid) rhabdomyosarcoma occurs in the extrahepatic bile ducts and rarely in the gallbladder, where it can secondarily extend into the hepatic hilus and often manifests with biliary obstruction. Rhabdomyosarcoma forms a mass composed of multiple filiform, polypoid intraluminal protrusions involving the bile ducts
Lack EE, Perez-Atayde AR, Schuster SR (1981)
Botryoid rhabdomyosarcoma of the biliary tract.
Am J Surg Pathol 5: 643-52
Al-Daraji WI, Makhlouf HR, Miettinen M, Montgomery EA, Goodman ZD, Marwaha JS, Fanburg-Smith JC (2009)
. Rhabdomyoblastic differentiation is variable, and coexpression of desmin and myogenic regulatory proteins (MYOD1, myogenin) is diagnostic. Prognosis is reasonably good with modern combined chemotherapy and surgery regimens; in one study, the estimated 5-year survival was 66%
Primary gallbladder sarcoma: a clinicopathologic study of 15 cases, heterogeneous sarcomas with poor outcome, except pediatric botryoid rhabdomyosarcoma.
Am J Surg Pathol 33: 826-34
Nicol K, Savell V, Moore J, Teot L, Spunt SL, Qualman S, (2007)
Distinguishing undifferentiated embryonal sarcoma of the liver from biliary tract rhabdomyosarcoma: a Children's Oncology Group study.
Pediatr Dev Pathol 10: 89-97
Bosman FT, Carneiro F, Hruban RH, Theise ND (Eds.)
WHO Classification of Tumours of the Digestive System.
International Agency for Research on Cancer: Lyon 2010