Prognostic factors in patients with localized and metastatic alveolar rhabdomyosarcoma. A report from two studies and two registries of the Cooperative Weichteilsarkom Studiengruppe CWS.

Background: The histologic classification of rhabdomyosarcoma (RMS) as alveolar (aRMS) or embryonal (eRMS) is of prognostic importance, with the aRMS being associated with a worse outcome. Specific gene fusions (PAX3/7::FOXO1) found in the majority of aRMS have been recognized as markers associated with poor prognosis and are included in current risk stratification instead of histologic subtypes in localized disease. In metastatic disease, the independent prognostic significance of fusion status has not been definitively established.

On TRacK With Larotrectinib in a Neonate With a Giant Congenital ETV6::NTRK3 Fusion-Positive Infantile Fibrosarcoma of the Head and Neck.

Background: Infantile fibrosarcoma (IFS) is a rare pediatric tumor of intermediate malignancy with high local aggressiveness that typically presents in young infants. Its occurrence in the head and neck region is rare. Complete non-mutilating surgical resection is often not possible, requiring multimodal treatment.

Maintenance therapy with trofosfamide, idarubicin and etoposide in patients with rhabdomyosarcoma and other high-risk soft tissue sarcomas (CWS-2007-HR): a multicentre, open-label, randomised controlled phase 3 trial.

Background: Rhabdomyosarcoma and other soft tissue sarcomas (STS) with high-risk features are still associated with an unsatisfactory outcome. We evaluated the efficacy of oral maintenance therapy added at the end of standard therapy in patients with high-risk rhabdomyosarcoma and STS.

Methods: CWS-2007-HR was a multicentre, open-label, randomised controlled, phase 3 trial done at 87 centers in 5 countries.

Treatment of Pediatric, Adolescent, and Young Adult Patients With Fusion-Positive Alveolar Rhabdomyosarcoma Infiltrating Regional Lymph Nodes in the European CWS-2002P and RMS 2005 Studies and the Soft Tissue Sarcoma Registry.

Background: Patients with alveolar rhabdomyosarcoma (ARMS) with regional lymph node involvement (N1) are defined as "very-high-risk rhabdomyosarcoma" in Europe. Different chemotherapy regimens were used in European study protocols.

Methods: Patients with FOXO1 fusion-positive N1 ARMS registered in the CWS-2002P study, the EpSSG RMS 2005 study, and SoTiSaR were retrospectively investigated.

Osteosarcoma as a secondary malignancy following rhabdomyosarcoma: A report of 28 affected patients from the Cooperative Osteosarcoma Study Group (COSS).

Background: Osteosarcoma may arise as a secondary malignancy following rhabdomyosarcoma (RMS). We utilized the Cooperative Osteosarcoma Study Group (COSS) database to better understand this association.

Patients And Methods: The COSS database (1980-05/2023) was searched for patients whose osteosarcoma was preceded by RMS.