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. Eligible patients were analyzed for patient-, tumor-, and treatment-related variables as well as outcomes. RESULTS: The search revealed 28 eligible osteosarcomas (27 high-grade central, one periosteal; male:female = 16:12; median age RMS 2.1 [range: 0.9-10.0] years, osteosarcoma 13.5 [7.2-29.0] years). Genetic tumor-predisposition syndromes were documented in 12 patients. One patient had had a distinct malignancy prior to RMS, two intermittently, seven following osteosarcoma. Local RMS treatment had included radiotherapy in 20/26 cases (two unknown). Secondary osteosarcoma sites were extremity 13, trunk seven, head and neck eight; 15 osteosarcomas were radiation-associated. There was only one case of primary osteosarcoma metastases. Osteosarcoma treatment included chemotherapy (27), surgery (26), or radiotherapy (2). A macroscopically complete remission of all osteosarcoma sites was achieved in 24 cases. Median follow-up was 5.8 (range: 0.5-18.4) years after osteosarcoma and 8.1 (1.0-15.4) years for 14 survivors. Actuarial 5-year overall and event-free survival were 66% (standard error 9%) and 45% (10%), respectively. Five of 14 deaths were caused by further malignancies. CONCLUSION: This series offers a benchmark for patients who develop a secondary osteosarcoma after RMS. Affected patients are generally still in the pediatric age. The results obtained strongly argue for genetic predisposition testing in RMS and against therapeutic leniency in comparable situations.

Second-line treatment of pediatric patients with relapsed rhabdomyosarcoma adapted to initial risk stratification: Data of the European Soft Tissue Sarcoma Registry (SoTiSaR).

BACKGROUND: Outcome of relapsed disease of localized rhabdomyosarcoma remains poor. An individual treatment approach considering the initial systemic treatment and risk group was included in the Cooperative Weichteilsarkom Studiengruppe (CWS) Guidance. METHODS: Second-line chemotherapy (sCHT) ACCTTIVE based on anthracyclines (adriamycin, carboplatin, cyclophosphamide, topotecan, vincristine, etoposide) was recommended for patients with initial low- (LR), standard- (SR), and high-risk (HR) group after initial treatment without anthracyclines. TECC (topotecan, etoposide, carboplatin, cyclophosphamide) was recommended after initial anthracycline-based regimen in the very high-risk (VHR) group. Data of patients with relapse (n = 68) registered in the European Soft Tissue Sarcoma Registry SoTiSaR (2009-2018) were retrospectively analyzed. RESULTS: Patients of initial LR (n = 2), SR (n = 16), HR (n = 41), and VHR (n = 9) group relapsed. sCHT consisted of ACCTTIVE (n = 36), TECC (n = 12), or other (n = 15). Resection was performed in 40/68 (59%) patients and/or radiotherapy in 47/68 (69%). Initial risk stratification, pattern/time to relapse, and achievement of second complete remission were significant prognostic factors. Microscopically incomplete resection with additional radiotherapy was not inferior to microscopically complete resection (p = .17). The 5-year event-free survival (EFS) and overall survival (OS) were 26% (±12%) and 31% (±14%). The 5-year OS of patients with relapse of SR, HR, and VHR groups was 80% (±21%), 20% (±16%), and 13% (±23%, p = .008), respectively. CONCLUSION: Adapted systemic treatment of relapsed disease considering the initial risk group and initial treatment is reasonable. New treatment options are needed for patients of initial HR and VHR groups.

Infantile myofibromatosis: Excellent prognosis but also rare fatal progressive disease. Treatment results of five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry.

BACKGROUND: Infantile myofibromatosis (IM) is a rare benign soft tissue tumor and often a self-limiting disease but rarely includes life-threatening complications. Little is known about optimal treatment of primary localized (LD) and multifocal disease (MFD). METHODS: Treatment and outcome of 95 children with IM registered within five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry (1981-2016) were evaluated. RESULTS: LD was diagnosed in 71 patients at a median age of 0.4 years (range 0.0-17.7). MFD was present in 24 patients. The mainstay of treatment was watch-and-wait strategy (w&w) after initial biopsy or resection. Low-dose chemotherapy (CHT) was administered to 16/71 (23%) patients with LD and eight of 24 (33%) patients with MFD, imatinib was added in two. A delayed resection was possible in eight of 71 (11%) and five of 24 (21%) patients with LD and MFD, respectively. Overall, patients were alive in complete remission (n = 77) and partial remission (n = 10) at a median follow-up time of 3.4 years after diagnosis (range 0.01-19.4); no data available (n = 5). Three patients died of progressive disease (PD) despite CHT. Gender, tumor size, and location correlated with a favorable event-free survival (EFS) in patients with LD. The 5-year EFS and overall survival of patients with LD were 73% (±12, confidence interval [CI] 95%) and 95% (±6, CI 95%), respectively; for MFD 51% (±22, CI 95%) and 95% (±10, CI 95%). CONCLUSION: Prognosis is excellent in patients with LD and MFD. Targeted treatment needs to be evaluated for rare fatal PD.

Rhabdomyosarcoma of the female genitourinary tract: Primary and relapsed disease in infants and older children. Treatment results of five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry.

BACKGROUND: Rhabdomyosarcoma (RMS) of the female genitourinary tract (FGU-RMS) located at the vagina or uterus is one of the most favorable RMS sites. Little is known about treatment and outcome in infants and relapsed disease (RD). METHODS: Characteristics, treatment, and outcome of 71 children with FGU-RMS registered within five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry (1981-2019) were evaluated. RESULTS: FGU-RMS was diagnosed in 67 patients with localized disease (LD) at a median age of 2.89 years (0.09-18.08). Multimodal treatment consisted of chemotherapy (CHT) (n = 66), secondary surgery (n = 32), and radiotherapy (n = 11). Age at diagnosis ≤12 months was the only significant negative prognostic factor influencing the event-free survival (EFS). Ten-year EFS and overall survival (OS) for infants ≤12 months were 50% and 81%, respectively. In contrast, children with LD >1 year and ≤10 years had a 10-year EFS and OS of 78% and 94% (P = .038), and >10 years of 82% and 88%, respectively (P = .53). Metastatic disease was observed in four patients of which three are alive. RD occurred in five of 12 infants ≤1 year and 10/55 children at a median of 1.38 years (0.53-2.97) after initial diagnosis. Treatment of patients with RD consisted of multimodal treatment (n = 13) or resection only (n = 2). Nine patients (60%) were alive in clinical remission at a median of 7.02 years (1.23-16.72) after diagnosis of RD. CONCLUSION: Infants with FGU-RMS have a higher relapse rate than older children with FGU-RMS, but prognosis is fair.

European guideline for imaging in paediatric and adolescent rhabdomyosarcoma - joint statement by the European Paediatric Soft Tissue Sarcoma Study Group, the Cooperative Weichteilsarkom Studiengruppe and the Oncology Task Force of the European Society of Paediatric Radiology.

Appropriate imaging is essential in the treatment of children and adolescents with rhabdomyosarcoma. For adequate stratification and optimal individualised local treatment utilising surgery and radiotherapy, high-quality imaging is crucial. The paediatric radiologist, therefore, is an essential member of the multi-disciplinary team providing clinical care and research. This manuscript presents the European rhabdomyosarcoma imaging guideline, based on the recently developed guideline of the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG) Imaging Committee. This guideline was developed in collaboration between the EpSSG Imaging Committee, the Cooperative Weichteilsarkom Studiengruppe (CWS) Imaging Group, and the Oncology Task Force of the European Society of Paediatric Radiology (ESPR). MRI is recommended, at diagnosis and follow-up, for the evaluation of the primary tumour and its relationship to surrounding tissues, including assessment of neurovascular structures and loco-regional lymphadenopathy. Chest CT along with [F-18]2-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET)/CT or PET/MRI are recommended for the detection and evaluation of loco-regional and distant metastatic disease. Guidance on the estimation of treatment response, optimal long-term follow-up, technical imaging settings and standardised reporting are described. This European imaging guideline outlines the recommendations for imaging in children and adolescents with rhabdomyosarcoma, with the aim to harmonise imaging and to advance patient care.

Malignant peripheral nerve sheath tumors in children, adolescents, and young adults: Treatment results of five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry.

BACKGROUND AND OBJECTIVES: Malignant peripheral nerve sheath tumors (MPNST) are aggressive soft tissue sarcomas that present as large, invasive tumors. Our aim was to assess outcomes, identify prognostic factors, and analyze treatment strategies in a prospectively collected pediatric cohort. METHODS: Patients less than 21 years with MPNST treated in the consecutive prospective European Cooperative Weichteilsarkom Studiengruppe (CWS)-trials (1981-2009) and the CWS-SoTiSaR registry (2009-2015) were analyzed. RESULTS: A total of 159 patients were analyzed. Neurofibromatosis type I (NF1) was reported in thirty-eight patients (24%). Most were adolescents (67%) with large (>10 cm, 65%) tumors located at extremities (42%). Nodal involvement was documented in 15 (9%) and distant metastases in 15 (9%) upon diagnosis. Overall, event-free survival (EFS) was 40.5% at 5 and 36.3% at 10 years, and overall survival (OS) was 54.6% at 5 and 47.1% at 10 years. Age, NF1 status, tumor site, tumor size, Intergroup Rhabdomyosarcoma Study (IRS) group, metastatic disease, and achieving first complete remission (CR1) were identified as prognostic factors for EFS and/or OS in the univariate analysis. CONCLUSIONS: Prognostic factors were identified and research questions for future clinical trials were addressed.

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. RESULTS: Median age was 8 years (range, 0.64-17.77). Fluorescence in situ hybridization analysis to detect COL1A1-PDGFB fusion genes was positive in 86% (12/14) of evaluated patients. Primary resection was performed in all patients. Patients had IRS group I (n = 28), II (n = 9), and III (n = 2); not available (n = 1). To achieve complete remission (CR), a secondary resection was performed in 18 patients resulting in microscopically complete (R0, n = 34/40) and microscopically incomplete (R1, n = 5/40) resection. All patients achieved CR. The 5-year event-free survival (EFS) and overall survival was 86% (±12; CI, 95%) and 100% (±0; CI, 95%), respectively. R0 resection/IRS I was significantly favorable for the 5-year EFS. Local relapse occurred after a median time of 1.1 years (range, 0.04-5.1) in 15% (6/40) after CR. All patients with RD underwent resection and achieved CR. Three patients had fibrosarcomatous DFSP, two were alive after R0 resection. CONCLUSION: Complete surgical resection is mandatory to prevent relapse of DFSP.

Low-grade fibromyxoid sarcoma: A report of the Cooperative Weichteilsarkom Studiengruppe (CWS).

BACKGROUND: Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft-tissue tumor with benign histologic appearance, though fully malignant behavior is possible. METHODS: Patients with LGFMS <21 years registered in Cooperative Weichteilsarkom Studiengruppe trials until 2017 were analyzed. Firstline treatment consisted of complete surgical resection whenever possible. RESULTS: Median age of 31 patients was 10.9 years (first month to 17.1 years). Twenty-six tumors were confirmed to the tissue of origin (T1), four invaded contiguous structures (T2), one was TX. Eight were >5 cm. The best surgical result was resection with free margins (R0) in 24 and microscopic residuals (R1) in seven. Five-year event-free (EFS), 5-year local-relapse-free (LRFS), and 5-year overall-survival were 71 ± 18.6% confidence interval (CI) 95%, 76 ± 17.6% CI 95%, and 100%, respectively. Six patients suffered local relapse in a median of 1 year, one combined within 1.3 year and one metastatic relapse with lesions in the lung, back muscles, and thigh discovered in whole-body imaging 6 years after the first diagnosis. In univariate analysis, T status correlated with EFS (T1 79.6 ± 18.6%, T2 50.0 ± 49.0%, P = .038). Resection with free margins tends to be associated with better LRFS (R0 82.4 ± 18.6%, R1 53.6 ± 39.4%, P = .053). Among 24 patients with R0 resection, five (21%) suffered relapse, thereof three local, one metastatic, and one combined. Among seven patients with R1-resection, three (43%) suffered local relapse. CONCLUSION: Special caution is advisable in T2 tumors. The metastatic potential with lesions in unusual sites indicates that affected patients need to be informed. If long-term follow-up with whole-body imaging is beneficial, it may be addressed in larger intergroup analyses. Further research in disease biology is essential for optimal treatment and follow-up care.

Endothelial cell malignancies in infants, children and adolescents: Treatment results of three Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry.

BACKGROUND: Endothelial cell malignancies are extremely rare in childhood. New identification of genetic abnormalities (WWTR1:CAMTA1 translocation) helps to recognize potential therapeutic targets. Little is known about treatment and outcome of these patients. METHODS: Clinical course, treatment, and outcome in patients with endothelial cell malignancies treated within the Cooperative Weichteilsarkom Studiengruppe (CWS) trials CWS-91, -96, -2002P, and the Soft-Tissue Sarcoma Registry (SoTiSaR) were analyzed (1991-2019). RESULTS: Patients had angiosarcoma (AS) (n = 12), malignant epithelioid hemangioendothelioma (EHE) (n = 16), and kaposiform hemangioendothelioma (KHE) (n = 13). The median age was 5.39 years (range, 0.8-17.34); 33 patients had localized disease (LD), and 8 patients had metastatic disease. Therapy consisted of chemotherapy (CHT) (AS n = 8, EHE n = 9, KHE n = 5), interferon or new agent therapy (EHE n = 5, 2 KHE n = 2), microscopically or macroscopically complete resection (AS n = 3, EHE n = 6, KHE n = 3), and radiotherapy (AS n = 6, EHE n = 2, KHE n = 1). Two patients (KHE) had watch-and-wait strategy resulting in stable disease. Complete remission (CR) was achieved in AS (10/12; 83%), EHE (10/16; 63%), and KHE (5/13; 38%). The five-year EFS and OS for patients with AS was 64% (± 29 CI 95%) and 80% (± 25, CI 95%), with EHE 62% (± 24, CI 95%) and 78% (± 23, CI 95%), with KHE 33% (± 34, CI 95%) and 92% (± 15, CI 95%), respectively. Complete resection was a significant prognostic factor for AS, LD for EHE. CONCLUSIONS: Endothelial cell malignancies in childhood have a fair outcome with multimodal treatment. New treatment options are needed for metastic disease.

Whole-body magnetic resonance imaging in pediatric oncology - recommendations by the Oncology Task Force of the ESPR.

The purpose of this recommendation of the Oncology Task Force of the European Society of Paediatric Radiology (ESPR) is to indicate reasonable applications of whole-body MRI in children with cancer and to address useful protocols to optimize workflow and diagnostic performance. Whole-body MRI as a radiation-free modality has been increasingly performed over the last two decades, and newer applications, as in screening of children with germ-line mutation cancer-related gene defects, are now widely accepted. We aim to provide a comprehensive outline of the diagnostic value for use in daily practice. Based on the results of our task force session in 2018 and the revision in 2019 during the ESPR meeting, we summarized our group's experiences in whole-body MRI. The lack of large evidence by clinical studies is challenging when focusing on a balanced view regarding the impact of whole-body MRI in pediatric oncology. Therefore, the final version of this recommendation was supported by the members of Oncology Task Force.

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. Cooperative Weichteilsarkom Studiengruppe (CWS) protocols recommend chemotherapy for all synovial sarcoma patients. RESULTS: Thirty-two of 330 patients with localized synovial sarcoma had their tumor at the foot/ankle. Eleven of thirty-two tumors were >5 cm. Twenty were T1, 11 T2, and one TX, respectively. Eight (25%) patients underwent primary complete resection with free margins (Intergroup Rhabdomyosarcoma Study [IRS] I), 12 of 32 (38%) primary complete resection with positive margins (IRS II), and 12 of 32 (38%) had macroscopic residuals (IRS III). The best surgical result at any time was R0 in 19, R1 in 10 and R2 in one patient, and missing in two. Mutilation was documented in 14 of 32 (44%). Radiotherapy was conducted in 20 patients. All patients achieved a first complete remission. Five-year-event-free survival and overall survival rates were 80% and 86%, respectively. Four patients suffered local and four other metastatic recurrences. IRS and the best surgical result at any time did not correlate with survival. There was no prognostic difference between R0- and R1-resection. CONCLUSION: Survival expectancies for patients with localized synovial sarcomas of the foot/ankle compare favorably to that of those with other affected sites. DISCUSSION: Further studies are needed to set the limits of minimally required aggressiveness of local therapies.

Epithelioid sarcoma in children, adolescents, and young adults: Localized, primary metastatic and relapsed disease. Treatment results of five Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry.

BACKGROUND: Epithelioid sarcoma (ES) is a rare malignant soft-tissue tumor. Little is known about the optimal treatment of primary localized (LD), metastatic (MD), and relapsed disease (RD). METHODS: Characteristics, treatment, and outcome of 67 patients registered within the Cooperative Weichteilsarkom Studiengruppe CWS-81, -86, -91, -96, -2002P trials and the registry SoTiSaR were analyzed (1981-2016). RESULTS: The median age was 14 years (range, 0.7-26.9); 53 patients had localized disease (LD) and 14 metastatic disease (MD). A total of 58 of 67 patients were treated with primary resection. Resection was microscopically complete (R0) in 35, microscopically incomplete (R1) in 12, macroscopically incomplete (R2) in 20 patients. Radiotherapy (RT) was administered to 33 of 67 patients and 49 of 67 patients received chemotherapy (CHT). Complete remission (CR) was achieved in 45 of 53 (85%) patients with LD. Twenty-seven of 53 patients relapsed after a median time of 0.9 years (range, 0.1-2.3). Relapse therapy consisted of resection (n = 19/27), RT (n = 10/27), CHT (n = 12/27), and limb perfusion (n = 3/27). The five-year event-free survival and overall survival of patients with LD, MD, and RD was 35% (± 12, CI 95%) and 58% (± 14, CI 95%), 7% (± 14, CI 95%), and 9% (± 16, CI 95%), 24% (± 17, CI 95%), and 40% (± 20, CI 95%), respectively. Tumor size, IRS group, tumor invasiveness, nodal status, and best resection correlated with a favorable prognosis in patients with LD while best resection was the only significant factor in patients with RD. CONCLUSIONS: Complete tumor resection correlates with long-term survival in patients with ES.

Rhabdomyosarcoma diagnosed in the first year of life: Localized, metastatic, and relapsed disease. Outcome data from five trials and one registry of the Cooperative Weichteilsarkom Studiengruppe (CWS).

BACKGROUND: Rhabdomyosarcoma (RMS) diagnosed during the first year of life is reported to have poor outcome. Little is known about treatment and outcome data of relapsed disease (RD). METHODS: Characteristics, treatment, and outcome of 155 patients ≤ 12 months registered within the Cooperative Weichteilsarkom Studiengruppe (CWS) between 1981 and 2016 were evaluated. RESULTS: Localized disease (LD) was diagnosed in 144 patients and metastatic disease (MD) in 11. The histological diagnosis was alveolar (RMA) (n = 38, 23/25 examined patients PAX7/3:FOXO1-positive), embryonal (RME) (n = 100), botryoid (n = 10), anaplastic (n = 1), and spindle-cell RMS (n = 6). Multimodal treatment including conventional (age-adjusted) chemotherapy (CHT) (n = 150), resection (n = 137), and radiotherapy (RT) (n = 37) was administered. Complete remission was achieved in 129 of 144 patients with LD. RD occurred in 51 infants at a median age of 1.7 years (range, 0.3-8.8). Sixty-three percent of patients with RMA suffered RD, in contrast to 28% of patients with RME. Relapse treatment consisted of conventional CHT (n = 48), resection (n = 28), and RT (n = 21). The pattern of relapse and best resection were significant prognostic factors for patients with RD (P = 0.000 and P = 0.002). Late effects occurred as secondary malignancies in 6%, long-term toxicity in 21%, and resection-related impairment in 33% of the 105 surviving patients. The 5-year event-free survival and overall survival for infants with initial LD were 51% and 69%, 14% and 14% for patients with initial MD and 39% and 41% for relapsed patients, respectively. CONCLUSION: Multimodal treatment including microscopically complete resection is strongly recommended to achieve a good prognosis in LD and RD of infants with RMS.

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. However, the best systemic treatment and response rates are currently unclear. METHODS: Thirty-eight patients under the age of 21, who were registered between 2000 and 2014 with a primary diagnosis of IMT, were analyzed. RESULTS: IMT was typically localized intra-abdominally or in the pelvis. In 20 patients, the tumor was resected without further therapy; 17 patients were in complete remission at last evaluation and two patients were in partial remission. Eighteen patients received systemic therapy, 15 of whom had macroscopically incomplete resection. Systemic therapy most commonly consisted of regimens with dactinomycin, ifosfamide or cyclophosphamide, and vincristine, with or without doxorubicin, and it seemed to reduce tumor extension in individual cases. Five-year event-free survival was 74 ± 14% and 5-year overall survival was 91 ± 10% for all patients. The patients who died due to the disease were those with incomplete resection (n = 3). CONCLUSIONS: Surgery without further systemic therapy was a feasible and acceptable therapeutic option for every second patient with IMT. Standard chemotherapy for pediatric soft tissue sarcoma produced favorable results in individual cases and was able to shrink the tumor enough to enable resection. Superior efficacy of new targeted therapies such as anaplastic lymphoma kinase-inhibitors compared to standard chemotherapy has to be proven in the future.

Alveolar soft-part sarcoma: Primary metastatic disease and metastatic relapse occurring during long-term follow-up: Treatment results of four Cooperative Weichteilsarkom Studiengruppe (CWS) trials and one registry.

BACKGROUND: Patients with metastatic alveolar soft-part sarcoma (ASPS) are known to have a very poor prognosis. Little is known about best treatment of primary metastatic disease (MD) or relapsed metastatic disease (rMD). PATIENTS AND METHODS: Patients with localized disease (LD), primary MD, and metastatic recurrence after complete remission (CR) treated within the CWS-86, -91, -96, -2002P trials and the recent registry SoTiSaR (1985-2016) were analyzed. RESULTS: Fifteen of 61 patients had primary metastases at initial diagnosis at the age of 14.6 years (range, 7.8-19.7). Nine of 46 patients with initial LD suffered of rMD at a median age of 9.9 years (range, 3.5-30), 3.75 years (0.75-21) after CR of primary disease. Complete resection (microscopically or macroscopically) was possible in 2 of 15 patients with MD and in 5 of 9 with rMD. RT was administered in 4 of 15 MD and 1 of 9 rMD. Chemotherapy was administered to 11 of 15 MD and 3 of 9 rMD, targeted therapy to 3 of 15 MD and 1 of 9 rMD. Median time to progression of patients treated with targeted therapy (n = 4), CHT (n = 14), and resection only (n = 6) was 56, 17, and 23 months, respectively. The 5-year event-free survival and overall survival (OS) rates were 19.8% and 61%, respectively, for patients with MD compared with 79% and 98% for patients with LD. The 5-year progression-free survival and OS were 67% and 100% for patients with rMD. CONCLUSIONS: Complete tumor resection correlates with long-term survival in patients with primary and relapsed MD.

Systemic therapy of aggressive fibromatosis in children and adolescents: Report of the Cooperative Weichteilsarkom Studiengruppe (CWS).

BACKGROUND: Treatment algorithms for patients with aggressive fibromatosis (AF) are challenging. There are limited data available about the use of systemic therapy (ST) in pediatric patients with AF. METHODS: Patient-, tumor-, and treatment-related factors of 90 children and adolescents with AF treated on multiple prospective trials of the Cooperative Weichteilsarkom Studiengruppe (1981-2015) were analyzed with focus on response and outcome of ST. RESULTS: Median age was 9.48 years (0.02-18.05). Primary resection was performed in 54 patients and ST was administered in 29 of 54 patients because of disease progression or relapse. In 35 patients, ST was the initial treatment modality. A secondary resection was performed in 21 of 35 patients after ST. A total of 64 patients received ST, mainly methotrexate and vinblastine (40%) with a median duration of 380 days. The most frequent radiological response to ST was stable disease at 3 months (39%) and partial response at 6 months (53%). Radiotherapy was administered to 15 of 90 patients. One patient remained on observation only. The 5-year overall survival was 100% and the 5-year event-free survival (EFS) was 44%. Patients who had a primary resection showed a 5-year EFS of 35% versus 59% in patients who had received primary ST (P = 0.08). Functional deficiencies as long-term sequelae following resection occurred in 11 patients. At a median follow-up of 5.05 years (0.25-14.88), complete remission was achieved in 51 patients and partial remission in 28 patients. CONCLUSIONS: ST seems appropriate if a primary complete resection is not feasible and at relapse/progression after resection.

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. MATERIALS AND METHODS: We retrospectively evaluated the data of prospectively registered paediatric patients (age <21 years) with alveolar rhabdomyosarcoma in the SoTiSaR (Soft Tissue Sarcoma Registry) of the Cooperative Weichteilsarkom Studiengruppe (CWS) 09/2011-04/2015 with regard to whole-body imaging. RESULTS: Seventy-five patients were eligible. Images of 57 patients had been submitted for reference consultation, including 80 whole-body examinations in 36 patients. Among them were 5 patients (14%, 95% confidence interval 3-25%) who had been diagnosed because of a symptomatic lesion while an additional silent lesion in the distal part of an extremity had remained unnoticed and had only been detected by later whole-body imaging. It is noteworthy that in 42 (53%) of all 80 whole-body examinations, the hands and feet had been only partially covered or completely excluded. CONCLUSION: In alveolar rhabdomyosarcoma silent lesions can be overlooked when the distal parts of the limbs are not thoroughly examined and not completely covered by imaging. Missing them influences treatment decisions and prognosis. Our results should be considered when evaluating the potential role of whole-body imaging in rhabdomyosarcoma.

Imaging of temporomandibular joint abnormalities in juvenile idiopathic arthritis with a focus on developing a magnetic resonance imaging protocol.

Inflammation and damage in the temporomandibular joint (TMJ) often develop without clinical symptoms but can lead to severe facial growth abnormalities and impaired health-related quality of life, making early diagnosis of TMJ changes crucial to identify. Inflammatory and osteochondral changes detectable through magnetic resonance imaging (MRI) occur in TMJs of approximately 40% of children with juvenile idiopathic arthritis (JIA), and no other imaging modality or physical method of examination can reliably detect these changes. Therefore contrast-enhanced MRI is the diagnostic standard for diagnosis and interval monitoring of JIA. However the specific usage of MRI for TMJ arthritis is not standardized at present. There is a recognized need for a consensus effort toward standardization of an imaging protocol with required and optional sequences to improve detection of pathological changes and shorten study time. Such a consensus imaging protocol is important for providing maximum information with minimally necessary sequences in a way that allows inter-site comparison of results of clinical trials and improved clinical management. In this paper we describe the challenges of TMJ imaging and present expert-panel consensus suggestions for a standardized TMJ MRI protocol.

The impact of local control in the treatment of type II/III pleuropulmonary blastoma. Experience of the Cooperative Weichteilsarkom Studiengruppe (CWS).

BACKGROUND AND OBJECTIVES: This study aims at examining the potential survival benefits of primary versus secondary surgery in the management of children diagnosed with pleuropulmonary blastoma (PPB) type II/III. PATIENTS AND METHODS: Disease characteristics, treatment, and survival of 29 children with localized PPB type II/III, treated in six prospective Cooperative Weichteilsarkom Studiengruppe (CWS) trials, were reviewed retrospectively. RESULTS: Five year event free survival (EFS) and overall survival (OS) of children treated according to CWS protocols was 72%. Patients with tumors ≤10 cm had a 5 year OS of 91% versus 57% in patients with tumors >10 cm (P = 0.025). Five year OS of patients with macroscopically incomplete upfront resections was 44% as opposed to 68% in patients with delayed/secondary microscopically or macroscopically complete resection after an initial biopsy (P = 0.476). Ten patients died of disease, one patient died of second malignancy. Tumor size and complete tumor resection at any time were significant prognostic factors (P = 0.025/0.003) for EFS. EFS for microscopically complete, microscopically incomplete, and macroscopically incomplete resection at any time was 91%, 90%, and 25%, respectively (P = 0.01). CONCLUSIONS: Primary or secondary microscopically/macroscopically complete tumor resections in combination with chemotherapy correlates with long term survival in children with PPB. J. Surg. Oncol. 2017;115:164-172. © 2017 Wiley Periodicals, Inc.

The prognostic value of early radiographic response in children and adolescents with embryonal rhabdomyosarcoma stage IV, metastases confined to the lungs: A report from the Cooperative Weichteilsarkom Studiengruppe (CWS).

BACKGROUND: Patients with metastatic rhabdomyosarcoma (RMS) have a poor prognosis apart from children with embryonal RMS whose metastases are confined to the lungs (PRME). The prognostic significance of response in patients with metastatic disease is still unknown and optimal treatment remains to be defined. METHODS: Patient-, tumor- and treatment-related factors of patients with PRME treated on multiple prospective trials of the Cooperative Weichteilsarkom Studiengruppe (CWS) (1981-2013) were analyzed with a focus on response to induction chemotherapy. Response at week 7-10 was based on anatomic imaging and determined (1) for the primary tumor as complete response (CR), good response (GR), partial response (PR) and no response (NR) and (2) for pulmonary metastases as either complete lack of residual lesions (pCR) or no complete response (no-pCR). Event-free (EFS) and overall survival (OS) were the endpoints. RESULTS: EFS and OS of all 53 eligible patients was 41% (±13 confidence interval [CI] 95%) and 52% (±11 CI 95%), respectively. pCR at week 7-10 and maintenance therapy (MT) were favorable prognostic factors. Interestingly, response of primary tumor at week 7-10 and number of metastases were not prognostic factors. The 5-year OS was 68% (±18 CI 95%) for 26 patients in pCR, but only 36% (±18 CI 95%) for 27 patients not in pCR at week 7-10 (P = 0.004) despite achieving pCR under continuation of chemotherapy or local therapy. CONCLUSION: Achievement of pCR at week 7-10 by induction chemotherapy is a prognostic factor.