Pineal anlage tumor: clinical and diagnostic features, and rationales for treatment.

PURPOSE: To provide a treatment-focused review and develop basic treatment guidelines for patients diagnosed with pineal anlage tumor (PAT). METHODS: Prospectively collected data of three patients with pineal anlage tumor from Germany was combined with clinical details and treatment information from 17 published cases. RESULTS: Overall, 20 cases of PAT were identified (3 not previously reported German cases, 17 cases from published reports). Age at diagnosis ranged from 0.3 to 35.0 (median: 3.2 ± 7.8) years. All but three cases were diagnosed before the age of three years. For three cases, metastatic disease at initial staging was described. All patients underwent tumor surgery (gross-total resection: 9, subtotal resection/biopsy: 9, extent of resection unknown: 2). 15/20 patients were alive at last follow-up. Median follow-up for 10/15 surviving patients with available follow-up and treatment data was 2.4 years (0.3-6.5). Relapse was reported for 3 patients within 0.8 years after diagnosis. Five patients died, 3 after relapse and 2 from early postoperative complications. Two-year-progression-free- and -overall survival were 65.2 ± 12.7% and 49.2 ± 18.2%, respectively. All 4 patients who received intensive chemotherapy including high-dose chemotherapy combined with radiotherapy (2 focal, 2 craniospinal [CSI]) had no recurrence. Focal radiotherapy- and CSI-free survival rates in 13 evaluable patients were 46.2% (6/13) and 61.5% (8/13), respectively. CONCLUSION: PAT is an aggressive disease mostly affecting young children. Therefore, adjuvant therapy using intensive chemotherapy and considering radiotherapy appears to comprise an appropriate treatment strategy. Reporting further cases is crucial to evaluate distinct treatment strategies.

Types of deviation and review criteria in pretreatment central quality control of tumor bed boost in medulloblastoma-an analysis of the German Radiotherapy Quality Control Panel in the SIOP PNET5 MB trial.

PURPOSE: In Germany, Austria, and Switzerland, pretreatment radiotherapy quality control (RT-QC) for tumor bed boost (TB) in non-metastatic medulloblastoma (MB) was not mandatory but was recommended for patients enrolled in the SIOP PNET5 MB trial between 2014 and 2018. This individual case review (ICR) analysis aimed to evaluate types of deviations in the initial plan proposals and develop uniform review criteria for TB boost. PATIENTS AND METHODS: A total of 78 patients were registered in this trial, of whom a subgroup of 65 patients were available for evaluation of the TB treatment plans. Dose uniformity was evaluated according to the definitions of the protocol. Additional RT-QC criteria for standardized review of target contours were elaborated and data evaluated accordingly. RESULTS: Of 65 initial TB plan proposals, 27 (41.5%) revealed deviations of target volume delineation. Deviations according to the dose uniformity criteria were present in 14 (21.5%) TB plans. In 25 (38.5%) cases a modification of the RT plan was recommended. Rejection of the TB plans was rather related to unacceptable target volume delineation than to insufficient dose uniformity. CONCLUSION: In this analysis of pretreatment RT-QC, protocol deviations were present in a high proportion of initial TB plan proposals. These findings emphasize the importance of pretreatment RT-QC in clinical trials for MB. Based on these data, a proposal for RT-QC criteria for tumor bed boost in non-metastatic MB was developed.

Zero incidence of factor VIII inhibitors and successful haemostatic response in previously factor VIII-treated patients with haemophilia A switching to turoctocog alfa in a noninterventional study.

INTRODUCTION: Turoctocog alfa (NovoEight® ) is a B-domain-truncated recombinant factor VIII (FVIII) approved for patients with haemophilia A. AIM: To investigate the long-term safety and efficacy of turoctocog alfa in routine clinical practice. METHODS: Guardian 5 was a prospective, multinational, non-interventional, post-authorisation safety study. Male previously treated patients (> 150 exposure days [EDs]) of any age with severe/moderately severe haemophilia A (FVIII ≤ 2%) and a negative inhibitor test prior to first dosing (independent of FVIII-inhibitor history) were included to receive prophylaxis or on-demand treatment. The primary endpoint was the proportion of patients developing FVIII inhibitors (≥.6 Bethesda Units [BU]) after baseline visit, measured as per routine practice of each study site during clinic visits. Secondary endpoints included haemostatic effect, annualised bleeding rate (ABR), and adverse reactions assessment. The study concluded when 50 patients reached 100 EDs/patient minimum. RESULTS: Seventy patients were screened and 68 exposed to turoctocog alfa; 63 (92.6%) were on prophylaxis and five received on-demand treatment. Six (8.8%) patients reported a history of positive inhibitors. During the study, patients were exposed to turoctocog alfa for a mean (standard deviation) of 131.9 (99.0) days/patient. Fifty-five of 58 patients who completed the study were tested for FVIII inhibitors; no positive tests were reported. Overall success rate of turoctocog alfa for treatment of bleeds was 87.3%. Among patients receiving prophylaxis, median (range) ABR was 1.97 (.0-25.5) bleeds/year; estimated ABR (negative binomial model) was 3.65 (95% confidence interval: 2.53-5.25). CONCLUSION: Turoctocog alfa was safe and efficacious for haemophilia A treatment in routine clinical practice.

Clinical and molecular characterization of isolated M1 disease in pediatric medulloblastoma: experience from the German HIT-MED studies.

PURPOSE: To evaluate the clinical impact of isolated spread of medulloblastoma cells into cerebrospinal fluid without additional macroscopic metastases (M1-only). METHODS: The HIT-MED database was searched for pediatric patients with M1-only medulloblastoma diagnosed from 2000 to 2019. Corresponding clinical and molecular data was evaluated. Treatment was stratified by age and changed over time for older patients. RESULTS: 70 patients with centrally reviewed M1-only disease were identified. Clinical data was available for all and molecular data for 45/70 cases. 91% were non-WNT/non-SHH medulloblastoma (Grp3/4). 5-year PFS for 52 patients ≥ 4 years was 59.4 (± 7.1) %, receiving either upfront craniospinal irradiation (CSI) or SKK-sandwich chemotherapy (CT). Outcomes did not differ between these strategies (5-year PFS: CSI 61.7 ± 9.9%, SKK-CT 56.7 ± 6.1%). For patients < 4 years (n = 18), 5-year PFS was 50.0 (± 13.2) %. M1-persistence occurred exclusively using postoperative CT and was a strong negative predictive factor (pPFS/OS < 0.01). Patients with additional clinical or molecular high-risk (HR) characteristics had worse outcomes (5-year PFS 42.7 ± 10.6% vs. 64.0 ± 7.0%, p = 0.03). In n = 22 patients ≥ 4 years with full molecular information and without additional HR characteristics, risk classification by molecular subtyping had an effect on 5-year PFS (HR 16.7 ± 15.2%, SR 77.8 ± 13.9%; p = 0.01). CONCLUSIONS: Our results confirm that M1-only is a high-risk condition, and further underline the importance of CSF staging. Specific risk stratification of affected patients needs attention in future discussions for trials and treatment recommendations. Future patients without contraindications may benefit from upfront CSI by sparing risks related to higher cumulative CT applied in sandwich regimen.

Pretreatment central quality control for craniospinal irradiation in non-metastatic medulloblastoma : First experiences of the German radiotherapy quality control panel in the SIOP PNET5 MB trial.

PURPOSE: Several studies have demonstrated the negative impact of radiotherapy protocol deviations on tumor control in medulloblastoma. In the SIOP PNET5 MB trial, a pretreatment radiotherapy quality control (RT-QC) program was introduced. A first analysis for patients enrolled in Germany, Switzerland and Austria with focus on types of deviations in the initial plan proposals and review criteria for modern radiation technologies was performed. METHODS AND PATIENTS: Sixty-nine craniospinal irradiation (CSI) plans were available for detailed analyses. RT-QC was performed according to protocol definitions on dose uniformity. Because of the lack of definitions for high-precision 3D conformal radiotherapy within the protocol, additional criteria for RT-QC on delineation and coverage of clinical target volume (CTV) and planning target volume (PTV) were defined and evaluated. RESULTS: Target volume (CTV/PTV) deviations occurred in 49.3% of initial CSI plan proposals (33.3% minor, 15.9% major). Dose uniformity deviations were less frequent (43.5%). Modification of the RT plan was recommended in 43.5% of CSI plans. Unacceptable RT plans were predominantly related to incorrect target delineation rather than dose uniformity. Unacceptable plans were negatively correlated to the number of enrolled patients per institution with a cutoff of 5 patients (p = 0.001). CONCLUSION: This prospective pretreatment individual case review study revealed a high rate of deviations and emphasizes the strong need of pretreatment RT-QC in clinical trials for medulloblastoma. Furthermore, the experiences point out the necessity of new RT-QC criteria for high-precision CSI techniques.

Ewing sarcoma.

Ewing sarcoma is a rare tumor that requires complex multidisciplinary management. This report describes the general management and standard radiotherapy guidelines in both North America (Children's Oncology Group) and Europe (International Society of Pediatric Oncology). Standard treatment involves multiagent induction chemotherapy followed by local treatment with surgery, definitive radiation, or a combination of surgery and radiation followed by additional chemotherapy and consolidation local treatment to metastatic sites. The data supporting the role of chemotherapy, surgery, and radiation and specific radiation therapy guidelines are presented.

Osteosarcoma.

Osteosarcoma is a rare tumor that requires complex multidisciplinary management. This paper reviews the general management and standard radiotherapy guidelines for osteosarcoma in both North America and Europe in a joined effort between the Children's Oncology Group and International Society of Pediatric Oncology. Standard treatment involves multiagent induction chemotherapy followed by surgical resection for local tumor control and consolidation local control to metastatic sites. Radiotherapy is reserved for cases with a marginal or incomplete resection or for definitive treatment in the case of unresectable disease. We present supporting data for the role of chemotherapy, surgery, and radiation therapy.

Management of vertebral radiotherapy dose in paediatric patients with cancer: consensus recommendations from the SIOPE radiotherapy working group.

Inhomogeneities in radiotherapy dose distributions covering the vertebrae in children can produce long-term spinal problems, including kyphosis, lordosis, scoliosis, and hypoplasia. In the published literature, many often interrelated variables have been reported to affect the extent of potential radiotherapy damage to the spine. Articles published in the 2D and 3D radiotherapy era instructed radiation oncologists to avoid dose inhomogeneity over growing vertebrae. However, in the present era of highly conformal radiotherapy, steep dose gradients over at-risk structures can be generated and thus less harm is caused to patients. In this report, paediatric radiation oncologists from leading centres in 11 European countries have produced recommendations on how to approach dose coverage for target volumes that are adjacent to vertebrae to minimise the risk of long-term spinal problems. Based on available information, it is advised that homogeneous vertebral radiotherapy doses should be delivered in children who have not yet finished the pubertal growth spurt. If dose fall-off within vertebrae cannot be avoided, acceptable dose gradients for different age groups are detailed here. Vertebral delineation should include all primary ossification centres and growth plates, and therefore include at least the vertebral body and arch. For partial spinal radiotherapy, the number of irradiated vertebrae should be restricted as much as achievable, particularly at the thoracic level in young children (<6 years old). There is a need for multicentre research on vertebral radiotherapy dose distributions for children, but until more valid data become available, these recommendations can provide a basis for daily practice for radiation oncologists who have patients that require vertebral radiotherapy.

Toxicity and risk factors after combined high-dose-rate brachytherapy and external beam radiation therapy in men ≥75 years with localized prostate cancer.

PURPOSE: Combined high-dose-rate brachytherapy (HDR-BT) and external beam radiation therapy (EBRT) is a favorable treatment option in non-metastatic prostate cancer. However, reports on toxicity and outcome have mainly focused on younger patients. We aimed to determine toxicity and biochemical control rates after combined HDR-BT and EBRT in men ≥75 years. METHODS: From 1999 to 2015, 134 patients aged ≥75 years (median 76 years; 75-82 years) were identified. Patients received 18 Gy of HDR-BT (9 Gy/fraction on days 1 and 8) with an iridium-192 source. After 1 week, supplemental EBRT with a target dose of 50.4 Gy was started (delivered in 1.8 Gy fractions). RESULTS: Median follow-up time was 25 months (0-127 months). No severe (grade 4) gastrointestinal (GIT) or genitourinary (GUT) toxicities were observed. In 76 patients (56.7%), 3D conformal radiation therapy (CRT) and in 34.3% intensity-modulated radiotherapy (IMRT) was applied. CRT-treated patients were at a 2.17-times higher risk (hazard ratio [HR]: 2.17, 95% confidence interval [CI]: 1.31-3.57, p = 0.002) of experiencing GUT. GIT risks could be reduced by 78% using IMRT (HR: 0.22, 95% CI: 0.07-0.75, p = 0.015). Patients with a higher T stage (T2c-3a/b) were less likely to experience GIT or GUT (HR: 0.49, 95% CI: 0.29-0.85, p = 0.011 and HR: 0.5, 95% CI: 0.3-0.81, p = 0.005, respectively). CONCLUSION: HDR-BT/EBRT is a well-tolerated treatment option for elderly men ≥75 years with a limited number of comorbidities and localized intermediate- or high-risk prostate cancer. IMRT should be favored since side effects were significantly reduced in IMRT-treated patients.

The impact of [68Ga]PSMA I&T PET/CT on radiotherapy planning in patients with prostate cancer.

PURPOSE: To determine the impact of Gallium-68-labled prostate-specific membrane antigen positron-emission tomography/computed tomography ([68Ga]PSMA PET/CT) on radiotherapy planning for primary disease, biochemical cancer relapse, and advanced disease of prostate cancer. METHODS: A total of 106 patients with prostate cancer scheduled for radiation therapy underwent 120 [68Ga]PSMA PET/CT scans prior to radiotherapy treatment. In 20 cases, patients underwent [68Ga]PSMA PET/CT for primary therapy (PT), 75 cases were referred for biochemical relapse after surgery (RL), and 25 cases were intended for palliative treatment of localized metastases (MD). We retrospectively compared the impact of [68Ga]PSMA PET/CT on lesion detection and treatment decision to CT alone. RESULTS: [68Ga]PSMA PET/CT revealed a total of 271 positive lesions, whereas CT detected 86 lesions (32%). Overall, the radiotherapy regime was changed in 55 of 120 cases (46%) based on the higher detection rate of [68Ga]PSMA PET/CT: in 15% of cases with PT, in 43% of cases with RL, and in 44% of cases with MD. CONCLUSION: [68Ga]PSMA PET/CT is superior to CT alone for lesion detection in prostate cancer, thereby significantly impacting on radiotherapy planning for primary disease, biochemical cancer relapse, and advanced disease of prostate cancer.

Adjuvant radiation therapy is associated with better oncological outcome compared with salvage radiation therapy in patients with pN1 prostate cancer treated with radical prostatectomy.

OBJECTIVE: To analyse the comparative effectiveness of no treatment (NT) or salvage radiation therapy (sRT) at biochemical recurrence (BCR) vs adjuvant radiation therapy (aRT) in patients with lymph node (LN)-positive prostate cancer (PCa) after radical prostatectomy (RP). PATIENTS AND METHODS: A total of 773 patients with LN-positive PCa at RP, with or without additional radiation therapy (RT), in the period 2005-2013, were retrospectively analysed. Cox regression analysis was used to assess factors influencing BCR and metastasis-free survival (MFS). Propensity score-matched analyses were performed. RESULTS: The median follow-up for the entire patient group was 33.8 months. Four-year BCR-free and MFS rates were 43.3% and 86.6%, respectively, for all patients. In multivariate analysis, NT/sRT (n = 505) was an independent risk factor for BCR and metastasis compared with aRT (n = 213). The superiority of aRT was confirmed after propensity score matching. The 4-year MFS in the matched cohort was 82.5% vs 91.8% for the NT/sRT and aRT groups, respectively (P = 0.02). Early sRT (pre-RT prostate-specific antigen [PSA] ≤0.5 ng/mL) compared with sRT at PSA >0.5 ng/mL was significantly associated with a lower risk of metastasis. CONCLUSION: Patients with LN-positive PCa who received aRT had a significantly better oncological outcome than patients with NT/sRT, independent of tumour characteristics. Patients with early sRT had higher rates of response and better MFS than patients with pre-RT PSA >0.5 ng/mL.

Additional androgen deprivation makes the difference: Biochemical recurrence-free survival in prostate cancer patients after HDR brachytherapy and external beam radiotherapy.

BACKGROUND: The role of additional androgen deprivation therapy (ADT) in prostate cancer (PCa) patients treated with combined HDR brachytherapy (HDR-BT) and external beam radiotherapy (EBRT) is still unknown. PATIENTS AND METHODS: Consecutive PCa patients classified as D'Amico intermediate and high-risk who underwent HDR-BT and EBRT treatment ± ADT at our institution between January 1999 and February 2009 were assessed. Multivariable Cox regression models predicting biochemical recurrence (BCR) were performed. BCR-free survival was assessed with Kaplan-Meier analyses. RESULTS: Overall, 392 patients were assessable. Of these, 221 (56.4 %) underwent trimodality (HDR-BT and EBRT and ADT) and 171 (43.6 %) bimodality (HDR-BT and EBRT) treatment. Additional ADT administration reduced the risk of BCR (HR: 0.4, 95 % CI: 0.3-0.7, p < 0.001). D'Amico high-risk patients had superior BCR-free survival when additional ADT was administered (log-rank p < 0.001). No significant difference for BCR-free survival was recorded when additional ADT was administered to D'Amico intermediate-risk patients (log-rank p = 0.2). CONCLUSIONS: Additional ADT administration improves biochemical control in D'Amico high-risk patients when HDR-BT and EBRT are combined. Physicians should consider the oncological benefit of ADT administration for these patients during the decision-making process.

Various regimens for prophylactic treatment of patients with haemophilia.

Haemophilia prophylaxis is superior to on-demand treatment to prevent joint damage. 'High-dose prophylaxis' as used in Sweden is more effective in preventing arthropathy than an 'intermediate-dose regimen' (the Netherlands) and the Canadian tailored primary prophylaxis. Prophylaxis may reduce the risk of developing inhibitors. There is no difference in inhibitor risk between plasma derived and recombinant factor VIII (rFVIII) products but the Rodin study showed increased risk with second-generation rFVIII products. MRI is a new and very sensitive tool to detect the symptoms of early arthropathy but some results (soft tissue changes in 'bleed-free joints') still need to be investigated. Ultrasound is a very helpful method to aid diagnosis especially during the acute phase of a bleed. The risk of infection with central venous access remains a matter of debate. A fully implanted central venous access device (CVAD) has a significant lower risk of infection compared to external CVADs. Patient's age under 6 yr and inhibitor presence are additional risk factors for infections. The role of arteriovenous fistulae needs to be investigated because significant complications have been reported. Disease-specific quality of life instruments are complementary to generic instruments evaluating QoL in patients with haemophilia and have become important health outcome measures.

Medulloblastoma in children with Fanconi anemia: Association with FA-D1/FA-N, SHH type and poor survival independent of treatment strategies.

BACKGROUND: The outcome of children with medulloblastoma (MB) and Fanconi Anemia (FA), an inherited DNA repair deficiency, has not been described systematically. Treatment is complicated by high vulnerability to treatment-associated side effects, yet structured data are lacking. This study aims to give a comprehensive overview of clinical and molecular characteristics of pediatric FA MB patients. METHODS: Clinical data including detailed information on the treatment and toxicities of 6 previously unreported FA MB patients were supplemented with data of 16 published cases. RESULTS: We identified 22 cases of children with FA and MB with clinical data available. All MBs with subgroup reporting were SHH-activated (n = 9), confirmed by methylation profiling in 5 patients. FA MB patients exclusively belonged to complementation groups FA-D1 (n = 16) or FA-N (n = 3). Patients were treated with postoperative chemotherapy only (50%) or radiotherapy (RT) ±â€…chemotherapy (27%). Of 23% did not receive adjuvant therapy. Excessive treatment-related toxicities were frequent. Severe hematological toxicity occurred in 91% of patients treated with alkylating chemotherapy, while non-alkylating agents and RT were less toxic. Median overall survival (OS) was 1 year (95%CI: 0.3-1.8). 1-year-progression-free-survival (PFS) was 26.3% ±â€…10.1% and 1-year-OS was 42.1% ±â€…11.3%. Adjuvant therapy prolonged survival (1y-OS/1y-PFS 0%/0% without adjuvant therapy vs. 53.3% ±â€…12.9%/33.3 ±â€…12.2% with adjuvant therapy, P = .006/P = .086). CONCLUSIONS: MB in FA patients is strongly associated with SHH activation and FA-D1/FA-N. Despite the dismal prognosis, adjuvant therapy may prolong survival. Non-alkylating chemotherapy and RT are feasible in selected patients with careful monitoring of toxicities and dose adjustments. Curative therapy for FA MB-SHH remains an unmet medical need.

Treatment response as surrogate to predict risk for disease progression in pediatric medulloblastoma with persistent magnetic resonance imaging lesions after first-line treatment.

BACKGROUND: This study aims at clarifying the impact of persistent residual lesions following first-line treatment for pediatric medulloblastoma. METHODS: Data on 84 pediatric patients with medulloblastoma and persistent residual lesions on centrally reviewed magnetic resonance imaging (MRI) at the end of first-line therapy were analyzed. RESULTS: Twenty patients (23.8%) had residual lesions in the tumor bed (R+/M0), 51 (60.7%) had distant lesions (R0/M+) and 13 (15.5%) had both (R+/M+). Overall response to first-line therapy was minor or partial (≥ 25% reduction, minor response [MR]/PR) for 64 (76.2%) and stable disease (SD) for 20 patients (23.8%). Five-year post-primary-treatment progression-free (pptPFS) and overall survival (pptOS) were superior after MR/PR (pptPFS: 62.5 ±â€…7.0%[MR/PR] vs. 35.9 ±â€…12.8%[SD], P = .03; pptOS: 79.7 ±â€…5.9[MR/PR] vs. 55.5 ±â€…13.9[SD], P = .04). Furthermore, R+/M + was associated with a higher risk for progression (5-year pptPFS: 22.9 ±â€…17.9%[R+, M+] vs. 72.4 ±â€…12.0%[R+, M0]; P = .03). Watch-and-wait was pursued in 58 patients, while n = 26 received additional treatments (chemotherapy only, n = 19; surgery only, n = 2; combined, n = 3; valproic acid, n = 2), and their outcomes were not superior to watch-and-wait (5-year pptPFS: 58.5 ±â€…7.7% vs. 51.6 ±â€…10.7% P = .71; 5-year pptOS: 76.3 ±â€…6.9% vs. 69.8 ±â€…9.7%, P = .74). For the whole cohort, 5-year pptPFS by molecular subgroup (58 cases) were WNT: 100%, SHH: 50.0 ±â€…35.4%, group-4, 52.5 ±â€…10.5, group-3 54.2 ±â€…13.8%; (P = .08). CONCLUSIONS: Overall response and extent of lesions can function as surrogate parameters to predict outcomes in pediatric MB patients with persistent lesions after first-line therapy. Especially in the case of solitary persistent medulloblastoma MRI lesions, additional therapy was not beneficial. Therefore, treatment response, extent/kind of residual lesions and further diagnostic information need consideration for indication of additional treatments for persisting lesions.

[Treatment of haemophilia in Austria]. / Hämophilie-Behandlung in Österreich.

This guideline is intended to provide practical guidance for the diagnosis and treatment of haemophilia in Austria. Few randomized controlled interventional trials are available addressing the treatment of haemophilia, therefore recommendations are usually based on low level of evidence and represent expert consensus.This guideline is based on the WFH guideline, published in 2020, and adapted according to the national circumstances and experience.It includes recommendations and suggestions for diagnosis and follow-up visits and pharmacological therapies for treatment and prophylaxis. Further topics comprise special aspects in children and adults with severe haemophilia, outcome measurement, and management of trauma, special bleedings and interventions, including dental procedures, inhibitors, management of haemophilia carriers, and psychosocial aspects.

Ultra-Late Osteosarcoma Recurrences: An Analysis of 17 Cooperative Osteosarcoma Study Group Patients with a First Recurrence Detected More Than 10 Years After Primary Tumor Diagnosis.

Purpose: Osteosarcoma is a typical malignancy of childhood and adolescence. Recurrences usually occur early, but rarely may arise after decades of remission. Little is known about these very late events and we set out to fill this knowledge gap. Methods: The database of the Cooperative Osteosarcoma Study Group (COSS) was searched for patients with a first recurrence of a high-grade central osteosarcoma occurring >10 years after diagnosis of the primary disease. Identified patients were analyzed for demographic, tumor-, and treatment-related factors as well as outcomes. Results: Among a total of 1,178 10-year relapse-free survivors, 17 affected patients were identified. Only five of these had a documented good response to initial chemotherapy. No presenting factor was identified to predict these very late events. Prognosis was generally very poor despite intensive multimodal therapy. Inoperability of the recurrences seems to have constituted a major limiting factor. Conclusion: Osteosarcoma patients should be followed for potential recurrences for well >10 years from initial diagnosis. Only through such an extended truly long-term follow-up and a structured transition of young patients can these be detected while they are still operable and, hence, potentially curable.

Efficacy and Feasibility of Proton Beam Therapy in Relapsed High-Risk Neuroblastoma-Experiences from the Prospective KiProReg Registry.

BACKGROUND: Despite an intensive multimodal treatment approach, approximately 50% of high-risk (HR) neuroblastoma (NB) patients experience progression. Despite the advances in targeted therapy, high-dose chemotherapy, and other systemic treatment options, radiation therapy (RT) to sites of relapsed disease can be an option to reduce tumor burden and improve chance for disease control. METHODS: Patients who received salvage irradiation with proton beam therapy (PBT) for local or metastatic relapse of HR NB within the prospective registry trials KiProReg and ProReg were eligible for this retrospective analysis. Data on patient characteristics, multimodality therapy, adverse events, and oncologic endpoints were evaluated. Adverse events were assessed before, during, and after PBT according to common terminology criteria for adverse events (CTCAE) V4.0. RESULTS: Between September 2013 and September 2020, twenty (11 male; 9 female) consecutive patients experiencing local (N = 9) or distant recurrence (N = 25) were identified for this analysis. Distant recurrences included osteomedullary (N = 11) or CNS lesions (N = 14). Salvage therapy consisted of re-induction chemo- or chemo-immuno-therapy (N = 19), surgery (N = 6), high-dose chemotherapy and stem cell transplantation (N = 13), radiation (N = 20), and concurrent systemic therapy. Systemic therapy concurrent to RT was given to six patients and included temozolomide (N = 4), carboplatine (N = 1), or anaplastic lymphoma kinase tyrosine kinase inhibitors (ALK-TKI) (N = 1). A median dose of 36 Gy was applied to the 34 recurrent sites. Local RT was applied to 15 patients, while five patients, received craniospinal irradiation for CNS relapse. After a median follow-up (FU) of 20 months (4-66), the estimated rate for local control, distant metastatic free survival, and overall survival at 3 years was 68.0%, 37.9%, and 61.6%, respectively. During RT, ten patients (50%) presented with a higher-grade acute hematologic adverse event. Late higher-grade sequelae included transient myelitis with transverse section (N = 2) and secondary malignancy outside of the RT field (N = 1). CONCLUSION: Our study demonstrates the efficacy and safety of RT/PBT for recurrent HR NB in a multimodality second-line approach. To better define the role of RT for these patients, prospective studies would be desirable.

QUARTET: A SIOP Europe project for quality and excellence in radiotherapy and imaging for children and adolescents with cancer.

The European Society for Paediatric Oncology (SIOPE) Radiation Oncology Working Group presents the QUARTET Project: a centralised quality assurance programme designed to standardise care and improve the quality of radiotherapy and imaging for international clinical trials recruiting children and adolescents with cancer throughout Europe. QUARTET combines the paediatric radiation oncology expertise of SIOPE with the infrastructure and experience of the European Organisation for Research and Treatment of Cancer to deliver radiotherapy quality assurance programmes for large, prospective, international clinical trials. QUARTET-affiliated trials include children and adolescents with brain tumours, neuroblastoma, sarcomas including rhabdomyosarcoma, and renal tumours including Wilms' tumour. With nine prospective clinical trials and two retrospective studies within the active portfolio in March 2022, QUARTET will collect one of the largest repositories of paediatric radiotherapy and imaging data, support the clinical assessment of radiotherapy, and evaluate the role and benefit of radiotherapy quality assurance for this cohort of patients within the context of clinical trials.