Practice Patterns of Stereotactic Radiotherapy in Pediatrics: Results From an International Pediatric Research Consortium

Guide for paediatric radiotherapy procedures

A third of children with cancer receive radiotherapy as part of their initial treatment, which represents 800 paediatric irradiations per year in France carried out in 15 specialized centres approved on the recommendations of the French national cancer institute in decreasing order of frequency, the types of cancer that require irradiation are: brain tumours, neuroblastomas, Ewing's sarcomas, Hodgkin's lymphomas, soft tissue sarcomas including rhabdomyosarcomas, and nephroblastomas. The treatment guidelines follow the recommendations of the French society for childhood cancers (SFCE) or the French and European prospective protocols. The therapeutic indications, the technical and/and ballistic choices of complex cases are frequently discussed during bimonthly paediatric radiotherapy technical web-conferences. All cancers combined, overall survival being 80%, long-term toxicity logically becomes an important concern, making the preparation of treatments complex. The irradiation methods include all the techniques currently available: 3D conformational irradiation, intensity modulation radiation therapy, irradiation under normal or hypofractionated stereotaxic conditions, brachytherapy and proton therapy. We present the update of the recommendations of the French society for radiation oncology on the indications, the technical methods of realization and the organisation and the specificities of paediatric radiation oncology.

Screening and Psycho-Oncological Support for Patients With Head and Neck Cancer and Brain Malignancies Before Radiotherapy With Mask Fixation: Results of a Feasibility Study

This single-center, single-arm trial investigates the feasibility of a psycho-oncological care program, which aims to reduce psychological distress and improve compliance with radiotherapy with mask fixation in patients with head and neck cancer or brain malignancies. The care program comprised (1) a screening/needs assessment and (2) the provision of a psycho-oncological intervention using imaginative stabilization techniques for distressed patients (distress due to anxiety ≥5) or in a case of subjective interest in the psycho-oncological intervention. Another allocation path to the intervention was directly through the radiation oncologist in charge who classified the patient as: in need of support to tolerate the immobilization device. Of a total of 1,020 screened patients, 257 (25.2%) patients indicated a distress ≥5 and 141 (13.8%) patients reported panic attacks. 25% of the patients reported a subjective interest in psycho-oncological support. A total of 35 patients received the psycho-oncological intervention, of which 74% were assigned by radiation oncologists. In this small patient cohort, no significant pre-post effects in terms of depression, anxiety, distress, and quality of life (mental and physical component scores) could be detected. Our results indicate a good feasibility (interdisciplinary workflow and cooperation, allocation by physicians in charge) of the psycho-oncological care program for this cohort of patients before radiotherapy with mask fixation. The screening results underline the high psychological distress and demand for psycho-oncological support. However, since the utilization of our intervention was low, future studies should reduce the barriers and improve compliance to psycho-oncological services by these patients.Clinical Trial Registration: https://www.drks.de/drks_web/setLocale_EN.do #DRKS00013493

Clinical outcomes for pediatric patients receiving radiotherapy for solid tumor central nervous system metastases

Central nervous system (CNS) metastases are rare, but devastating complications of pediatric solid tumors. Radiotherapy alone or postresection serves as an important treatment; however, data on the use of whole-brain radiotherapy (WBRT) versus focal radiotherapy, including stereotactic radiosurgery or stereotactic radiotherapy, for these indications are limited. We report a single institution experience of 26 pediatric patients treated with radiotherapy for solid tumor CNS metastases without leptomeningeal disease. Focal radiotherapy (n = 10) was well tolerated and survival outcomes did not differ between patients treated with WBRT (n = 16) versus focal radiation, suggesting that focal radiotherapy may be considered for patients with limited CNS metastases.

Hypofractionated stereotactic body radiation therapy (SBRT) in pediatric patients: preliminary toxicity results of a national prospective multicenter study

OBJECTIVES

While hypofractionated stereotactic body radiotherapy (SBRT) has been largely adopted in the adult setting, its use remains limited in pediatric patients. This is due, among other factors, to fear of potential toxicities of hypofractionated regimens at a young age. In this context, we report the preliminary acute (<3 months from SBRT) and middle-term (3-24 months) toxicity results of a national prospective study investigating SBRT in pediatric patients.

METHODS

Between 2013 and 2019, 61 patients were included. The first 40 patients (median age: 12 y, range: 3-20) who completed a 2-year-follow-up were included in the present analysis. SBRT was used for treating lung, brain or (para)spinal lesions, either as first irradiation (35%) or in the reirradiation setting (65%).

RESULTS

Acute and middle-term grade ≥2 toxicities occurred in 12.5 and 7.5% of the patients, respectively. No grade ≥4 toxicities occurred. Almost all toxicities occurred in the reirradiation setting.

CONCLUSION

SBRT showed a favorable safety profile in young patients treated for lung, brain, and (para)spinal lesions.

ADVANCES IN KNOWLEDGE

SBRT appeared to be safe in pediatric patients treated for multiple oncology indications. These results support further evaluation of SBRT, which may have a role to play in this patient population in the future.

Radical radiotherapy for paediatric solid tumour metastases: An overview of current European protocols and outcomes of a SIOPE multicenter survey

PURPOSE/OBJECTIVE

About 20% of children with solid tumours (ST) present with distant metastases (DM). Evidence regarding the use of radical radiotherapy of these DM is sparse and open for personal interpretation. The aim of this survey was to review European protocols and to map current practice regarding the irradiation of DM across SIOPE-affiliated countries.

MATERIALS/METHODS

Radiotherapy guidelines for metastatic sites (bone, brain, distant lymph nodes, lung and liver) in eight European protocols for rhabdomyosarcoma, non-rhabdomyosarcoma soft-tissue sarcoma, Ewing sarcoma, neuroblastoma and renal tumours were reviewed. SIOPE centres irradiating ≥50 children annually were invited to participate in an online survey.

RESULTS

Radiotherapy to at least one metastatic site was recommended in all protocols, except for high-risk neuroblastoma. Per protocol, dose prescription varied per site, and information on delineation and treatment planning/delivery was generally missing. Between July and September 2019, 20/27 centres completed the survey. Around 14% of patients were deemed to have DM from ST at diagnosis, of which half were treated with curative intent. A clear cut-off for a maximum number of DM was not used in half of the centres. Regardless of the tumour type and site, conventional radiotherapy regimens were most commonly used to treat DM. When stereotactic radiotherapy was used, a wide range of fractionation regimens were applied.

CONCLUSION

Current radiotherapy guidelines for DM do not allow a consistent approach in a multicentre setting. Prospective (randomised) trials are needed to define the role of radical irradiation of DM from paediatric ST.

Stereotactic Body Radiation Therapy for Metastatic and Recurrent Solid Tumors in Children and Young Adults

PURPOSE

The use of stereotactic body radiation therapy (SBRT) in pediatric patients has been underreported. We reviewed practice patterns, outcomes, and toxicity of SBRT in this population.

METHODS AND MATERIALS

In this multi-institutional study, 55 patients with 107 non-central nervous system lesions treated with SBRT between 2010 and 2016 were reviewed. Treatment response was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 and modified RECIST v1.1 criteria for soft-tissue and bone lesions, respectively. Patterns of local failure (LF) were assessed dosimetrically. The cumulative incidence of LF and toxicity were estimated accounting for the competing risk event of death. Predictors of LF were identified through joint frailty models for clustered competing risks.

RESULTS

The median (range) dose/fraction was 7 (4.5-25) Gy, the total (range) dose/site was 35 (12-45), and the median (range) number of fractions was 5 (1-9). The radiographic response rates of bone and soft-tissue lesions were 90.6% and 76.7%, respectively. Symptom improvement was observed for 62% of symptomatic sites. A total of 27 LFs were documented, with 14 in-field, 9 marginal, and 4 out-of-field LFs. The 1-year estimated cumulative LF rate, progression-free survival, and overall survival were 25.2% (95% confidence interval [CI], 17.2%-36.1%), 17.5% (95% CI, 9.0%-34.1%), and 61% (95% CI, 48.9%-76.1%), respectively. Lesion type (soft tissue vs bone) was the only significant predictor of LF on multivariable analysis (P = .04), with increased hazard for soft-tissue lesions. No acute or late toxicity of grade 4 or higher was observed; the estimated 1-year cumulative incidence of late toxicity of any grade was 7.5% (95% CI, 3.6%-12.1%).

CONCLUSIONS

The SBRT was well tolerated and resulted in radiographic response and symptom palliation in most pediatric patients with advanced disease. The 1-year cumulative LF rate of 25% will serve as a benchmark for further modifications to radiation therapy indications, parameters, and combination therapy.

Successful use of frameless stereotactic radiosurgery for treatment of recurrent brain metastases in an 18-month-old child

There are very few reported cases of stereotactic radiosurgery (SRS) delivered in children under 3 years of age. We report an 18-month-old boy with metastatic recurrence of undifferentiated round cell sarcoma to the brain which was treated with chemotherapy, resection and robotic frameless SRS. Frameless SRS was delivered without technical difficulties, acute adverse events, or clinical sequelae 1.5 months post-radiation. Longer term follow-up will be needed to evaluate local tumor control and effects on neurocognitive development, endocrine function and growth. This report adds to the literature of the few reported cases of successfully attempted SRS in very young children.