Fusion transcripts as liquid biopsy markers in alveolar rhabdomyosarcoma and synovial sarcoma: A report of the Cooperative Weichteilsarkom Studiengruppe (CWS).

Background: The possible application of gene fusion transcripts as tumor-specific noninvasive liquid biopsy biomarkers was investigated in blood plasma from patients with alveolar rhabdomyosarcoma (ARMS) and synovial sarcoma (SS).

Methods: Patients entered in the CWS Soft-Tissue Sarcoma Registry (SoTiSaR) with tumors positive for fusion genes and available blood/plasma samples were included in our analysis. Cell-free exosomal RNA was extracted and used to detect PAX-FOXO1 or SYT-SSX fusion transcripts by reverse transcription quantitative PCR (RT-qPCR).

Dermatofibrosarcoma protuberans in children and adolescents: Primary and Relapsed disease-Experience of the Cooperative Weichteilsarkomstudiengruppe (CWS).

Background: Dermatofibrosarcoma protuberans (DFSP) is a rare low-grade tumor. Little is known about best treatment of primary and relapsed disease (RD).

Methods: Treatment and outcome of 40 patients with DFSP prospectively registered within the CWS-96 and -2002P trials and the registry SoTiSaR (1996-2016) were analysed.

Synovial sarcoma disease characteristics and primary tumor sites differ between patient age groups: a report of the Cooperative Weichteilsarkom Studiengruppe (CWS).

Background: Older age is associated with worse outcome in synovial sarcoma (SS) patients. Differences in disease presentation among distinct age groups, however, are currently unknown.

Methods: SS patients < 21 years registered in consecutive CWS trials over the period of 1981-2018 were evaluated.

Localized synovial sarcoma of the foot or ankle: A series of 32 Cooperative Weichteilsarkom Study Group patients.

Background: Synovial sarcoma of the foot/ankle is rare. Mutilating surgery is often discussed.

Methods: Patients registered from 1981 to 2013 were analyzed.

Inflammatory myofibroblastic tumors-A retrospective analysis of the Cooperative Weichteilsarkom Studiengruppe.

Background: Inflammatory myofibroblastic tumors (IMTs) are a rare subgroup of soft tissue tumors. The outcome of patients with IMT has been reported as favorable when the tumor is completely resected. If surgical resection is not possible, systemic therapy has to be considered.

Importance of whole-body imaging with complete coverage of hands and feet in alveolar rhabdomyosarcoma staging.

Background: Alveolar rhabdomyosarcoma commonly arises in the extremities and is characterized by aggressive biology and high frequency of metastases. Whole-body imaging is increasingly employed in pediatric oncology but not recommended as standard in the staging of soft-tissue sarcomas.

Objective: After observing patients with a large symptomatic alveolar rhabdomyosarcoma lesion and a smaller silent lesion in the more distal part of an extremity we sought to estimate the frequency of this constellation.

Targeting hedgehog signaling reduces self-renewal in embryonal rhabdomyosarcoma.

Current treatment regimens for rhabdomyosarcoma (RMS), the most common pediatric soft tissue cancer, rely on conventional chemotherapy, and although they show clinical benefit, there is a significant risk of adverse side effects and secondary tumors later in life. Therefore, identifying and targeting sub-populations with higher tumorigenic potential and self-renewing capacity would offer improved patient management strategies. Hedgehog signaling has been linked to the development of embryonal RMS (ERMS) through mouse genetics and rare human syndromes.

Tumour volume reduction after neoadjuvant chemotherapy impacts outcome in localised embryonal rhabdomyosarcoma.

Background: Response (tumour volume reduction) to induction chemotherapy has been used to stratify secondary local and systemic treatment of Intergroup Rhabdomyosarcoma Study Group III (IRSG-III) embryonal rhabdomyosarcoma (RME) in consecutive CWS-trials. To evaluate its actual impact we studied response-related treatment and outcomes.

Procedure: Patients with IRSG-III RME <21 years and non-response (NR, <33% volume reduction) in five consecutive CWS-trials were analysed and compared with partial responders (PAR, ≥ 33% reduction).

Challenges in the local treatment of large abdominal embryonal rhabdomyosarcoma.

Background: Embryonal rhabdomyosarcoma is the most common pediatric soft tissue sarcoma. The best local treatment in large, nonmetastatic primary unresected nongenitourinary embryonal rhabdomyosarcoma of the abdomen (LARME) is however unclear.

Methods: We analyzed patients with LARME treated in four consecutive CWS trials.