Rhabdomyosarcoma and Skeletal Muscle Sarcomas

Alternative diagnostic terms
None

Common anatomical locations
Deep tissue of the upper and lower extremities.

Pathology comment
The presence of either a PAX3-FOXO1 or a PAX7-FOXO1 fusion gene is detected in the majority of cases.

Source
Cunha IW, Kohashi K, Bode-Lesniewska B. Alveolar rhabdomyosarcoma. In: WHO Classification of Tumors Editorial Board. Soft tissue and bone tumors [Internet]. Lyon (France): International Agency for Research on Cancer; 2020 [2024 Dec 29]. (WHO classification of tumors Series, 5th ed.; vol. 3). Available from: https://tumourclassification.iarc.who.int/login?redirecturl=%2Fchapters%2F33

For diagnosis or treatment
Any center listed in the Sarcoma Centers Directory »

Patient advocacy
Any organization with an established program for patient triage, support, and education. See Patient Support Organizations »

Clinical trials
SARC Clinical Trials – None
Find other clinical studies registered on ClinicalTrials.gov

Alternative diagnostic terms
None

Common anatomical locations
40-50% of ERMS occur within the head and neck(orbit) region, and 40-50% occur within the genitourinary system.

Pathology comment
Primitive round and spindle cell morphology with scattered differentiated rhabdomyoblasts; positivity for desmin and heterogeneous nuclear staining for myogenin and/or MYOD1. Lack of FOXO1 gene fusion distinguishes ERMS from ARMS. ERMS has an anaplastic subtype sarcoma botryoides is an antiquated diagnostic term.

Source
Cunha IW, Rudzinski ER, Khan J. Embryonal rhabdomyosarcoma. In: WHO Classification of Tumors Editorial Board. Soft tissue and bone tumors [Internet]. Lyon (France): International Agency for Research on Cancer; 2020 [2024 Dec 29]. (WHO Classification of Tumors Series, 5th ed.; vol. 3). Available from: https://tumourclassification.iarc.who.int/login?redirecturl=%2Fchapters%2F33

For diagnosis or treatment
Any center listed in the Sarcoma Center Directory »

Patient advocacy
Any organization with an established program for patient triage, support, and education. See Patient Support Organizations »

Diagnostic-specific organizations:
Summer’s Way Foundation
Focus on Rhabdo

Clinical trials
SARC Clinical Trials – None
Find other clinical studies registered on ClinicalTrials.gov

Alternative diagnostic terms
None

Common anatomical locations
Deep soft tissues of the lower and upper extremity.

Pathology comment
Pleomorphic cells with copious brightly eosinophilic cytoplasm; immunolabelling for desmin and myogenin.

Source
Cunha IW, Montgomery EA, Dry SM. Pleomorphic rhabdomyosarcoma. In: WHO Classification of Tumors Editorial Board. Soft tissue and bone tumors [Internet]. Lyon (France): International Agency for Research on Cancer; 2020 [2024 Dec 29]. (WHO Classification of Tumors Series, 5th ed.; vol. 3). Available from: https://tumourclassification.iarc.who.int/login?redirecturl=%2Fchapters%2F33

For diagnosis or treatment
Any center listed in the Sarcoma Centers Directory »

Patient advocacy
Any organization with an established program for patient triage, support, and education. See Patient Support Organizations »

Clinical trials
SARC Clinical Trials – None
Find other clinical studies registered on ClinicalTrials.gov

Alternative diagnostic terms
Sclerosing rhabdomyosarcoma

Subtypes (Recommended by WHO)
Congenital spindle cell rhabdomyosarcoma with VGLL2/NCOA2/CITED2 rearrangements
Intraosseous spindle cell rhabdomyosarcoma with TFCP2/NCOA2 rearrangements
MYOD1-mutant spindle cell/Sclerosing rhabdomyosarcoma

Common anatomical locations
Head and neck region

Pathology comment
Cellular spindle cell fascicles or tumor cells in a variably sclerotic collagenous background; positivity for desmin, myogenin (focal), and MYOD1.

Source
Cunha IW, Agaram NP, Szuhai K. Spindle cell / sclerosing rhabdomyosarcoma. In: WHO Classification of Tumors Editorial Board. Soft tissue and bone tumors [Internet]. Lyon (France): International Agency for Research on Cancer; 2020 [2024 Dec 29]. (WHO Classification of Tumors Series, 5th ed.; vol. 3). Available from: https://tumourclassification.iarc.who.int/login?redirecturl=%2Fchapters%2F33

For diagnosis or treatment
Any center listed in the Sarcoma Center Directory »

Patient advocacy
Any organization with an established program for patient triage, support, and education. See Patient Support Organizations »

Clinical trials
SARC Clinical Trials – None
Find other clinical studies registered on ClinicalTrials.gov

Alternative diagnostic terms
Pediatric Rhabdoid Tumor of Soft Tissue

Common anatomical locations
Most often in deep, axial locations such as the neck, paraspinal region, perineal region, abdominal cavity or retroperitoneum, and pelvic cavity.

Pathology comment
Mainly affects infants and children. Morphologically and genetically identical tumors also arise in the kidney and brain. The majority of tumors are characterized by biallelic alterations of the SMARCB1 gene leading to loss of expression of SMARCB1 (INI1).

Source
Fletcher CDM, Oda Y, Biegel JA, Pfister SM. Extrarenal rhabdoid tumor. In: WHO Classification of Tumors Editorial Board. Soft tissue and bone tumors [Internet]. Lyon (France): International Agency for Research on Cancer; 2020 [2024 Dec 29]. (WHO Classification of Tumors Series, 5th ed.; vol. 3). Available from: https://tumorclassification.iarc.who.int/chapters/33

For diagnosis or treatment
Any center listed in the Sarcoma Center Directory »

Patient advocacy
Any organization with an established program for patient triage, support, and education. See Patient Support Organizations »

Clinical trials
SARC Clinical Trials – None
Find other clinical studies registered on ClinicalTrials.gov

Alternative diagnostic terms
Rhabdomyoma
Ectomesenchymoma

Common anatomical locations
Pending

Pathology comment
Pending

Source
Pending