embryonal rhabdomyosarcoma

Embryonal rhabdomyosarcoma is the cellular subtype in slightly more than half of patients.

Breakpoints involving the 1p11-1q11 region are relatively common (36%) in embryonal rhabdomyosarcoma.

High birth weight and larger than expected size at birth are linked with an increased risk of embryonal rhabdomyosarcoma.

Its two most common forms are embryonal rhabdomyosarcoma and alveolar rhabdomyosarcoma.

This subtype has a more favorable clinical course and prognosis than usual embryonal rhabdomyosarcoma.

The spindle cell variant of embryonal rhabdomyosarcoma is most frequently observed at the paratesticular site.

Embryonal rhabdomyosarcoma.

It is expressed at higher levels in alveolar rhabdomyosarcoma than in embryonal rhabdomyosarcoma.

It has different cellular subtypes, including embryonal rhabdomyosarcoma and aveolar rhabdomyosarcoma.

Leuschner I: Spindle cell rhabdomyosarcoma: histologic variant of embryonal rhabdomyosarcoma with association to favorable prognosis.

Spindle cell rhabdomyosarcoma is a subtype of embryonal rhabdomyosarcoma first described by Cavazzana, Schmidt and Ninfo in 1992.

Newly diagnosed patients with metastatic rhabdomyosarcoma (excluding patients younger than 10 years with embryonal rhabdomyosarcoma) who have an expected failure-free survival of less than 20% are eligible.

Samuel DP, Tsokos M, DeBaun MR: Hemihypertrophy and a poorly differentiated embryonal rhabdomyosarcoma of the pelvis.

Williamson D, Missiaglia E, de Reyniès A, et al.: Fusion gene-negative alveolar rhabdomyosarcoma is clinically and molecularly indistinguishable from embryonal rhabdomyosarcoma.

Rhabdomyosarcoma can be divided into several histologic subsets: embryonal rhabdomyosarcoma, which has embryonal, botryoid, and spindle cell subtypes; alveolar rhabdomyosarcoma; and pleomorphic rhabdomyosarcoma.

This category includes patients with embryonal rhabdomyosarcoma at unfavorable sites who have gross residual disease (i.e., Group III), and patients with nonmetastatic alveolar rhabdomyosarcoma at any site.

Godbole P, Outram A, Wilcox DT, et al.: Myogenin and desmin immunohistochemistry in the assessment of post-chemotherapy genitourinary embryonal rhabdomyosarcoma: prognostic and management implications.

Embryonal rhabdomyosarcoma (ERMS) is a rare histological form of cancer of connective tissue wherein the mesenchymally-derived malignant cells resemble the primitive developing skeletal muscle of the embryo.

Although botryoid and spindle cell rhabdomyosarcoma are classically considered as subtypes of embryonal rhabdomyosarcoma, they have more favorable clinical behavior and prognosis than classic embryonal rhabdomyosarcoma.

Histopathologically rhabdomyosarcoma can be divided into two major subtypes, embryonal rhabdomyosarcoma representing about 80% of the clinical cases, and alveolar rhabdomyosarcoma representing about 20% of the total cases [ 1 2 ] .

Baker KS, Anderson JR, Link MP, et al.: Benefit of intensified therapy for patients with local or regional embryonal rhabdomyosarcoma: results from the Intergroup Rhabdomyosarcoma Study IV.

Low-risk patients have a localized (nonmetastatic) embryonal histology tumor in a favorable site, or a localized embryonal rhabdomyosarcoma in an unfavorable site that has been grossly resected (Surgico-pathologic Groups I and II).

The outcome for patients with translocation-negative alveolar rhabdomyosarcoma was better than that observed for translocation-positive cases and was similar to that seen in patients with embryonal rhabdomyosarcoma, suggesting that fusion status is a critical factor for risk stratification in pediatric rhabdomyosarcoma.

These included patients with tumors at favorable sites and positive lymph nodes, patients with gross residual disease, or patients with tumors at unfavorable sites who underwent grossly complete resections, but not patients with unresected embryonal rhabdomyosarcoma at unfavorable sites.