Radiotherapy management of paediatric cancers with synchronous metastasis

Cancer in childhood represent 1% of all the new diagnosed cancers. About 30% of children with cancer receive radiation therapy, representing about 600 to 700 patients per year in France. As a consequence, paediatric cancers with synchronous metastasis is a very rare situation in oncology, with usually poor standard of care. However, considerable efforts are made by paediatric oncology scientific societies to offer trials or treatment consensus despite these rare situations. The article proposes to synthesize the radiotherapy management of both primary tumour and synchronous metastasis in the most "common" childhood or adolescent cancers.

[Characteristics of radiotherapy for adolescents and young adults]

Radiotherapy for adolescents and young adults is complex in several aspects. The population is very heterogeneous and has characteristics derived from both paediatric and adult populations both in terms of pathology (anatomical pathology, response to treatment) and the patient's physical, biological and psychological characteristics. This article reviews the characteristics to be taken into account in adolescent and young adult patients radiotherapy and more particularly in some of the most common diseases.

Predicting Acute Radio-Induced Toxicity for Head and Neck Cancer Patients: Combining Dosimetry with Biomarker Data, Disclosing a Synergistic Effect

PURPOSE/OBJECTIVE(S)

We aimed to establish the added value of combining dosimetry with a binary blood assay for radiosensitivity based on quantification of pATM protein (RADIODTECT©) to predict acute radiotherapy (RT) induced mucositis (MUC) and dysphagia (DYS) in head & neck cancer patients (pts).

MATERIALS/METHODS

We enrolled 101 pts prospectively scored for acute toxicity with CTCAE. We considered four endpoints: grade≥2 (G2+) and grade≥3 (G3+) MUC, G2+, and G3+ DYS. We dichotomized the pATM concentration to define radiosensitive (RS) vs. radioresistant (RR) pts using previously described cutoffs for G2+ (57.8 ng/mL) and G3+ toxicity (46 ng/mL). We did RADIODTECT© and toxicity scoring blindly. We considered two already published NTCP models, including (i) the Equivalent Uniform Dose to the oral cavity (n = 0.05, EUD_OC, Odds Ratio [OR] = 1.02) and the mean dose to the parotid glands (Dmean_PG, OR = 1.06) for MUC and (ii) EUD_OC (OR = 1.04), the glottic larynx EUD (n = 0.35, EUD_GL, OR = 1.02) and the volume of pharyngeal constrictor muscles receiving>50Gy (V50Gy_CM, OR = 1.02) for DYS. To account for the association of toxicity with the dose distribution in multiple organs at risk (OARs), we derived a "Weighted Dose Score" (WDS) as a linear combination of the dose factors, using their β-coefficients (= lnOR) as weights. WDS for MUC (WDS_OM) = 0.06*Dmean_PG + 0.02*EUD_OC WDS for DYS (WDS_DYS) = 0.02*V50Gy_CM + 0.02*EUD_GL + 0.04*EUD_OC We used WDS as a comprehensive dose feature to fit a dose response and allowed WDS50 (i.e., the WDS associated with 50% toxicity probability) to be different for RR (WDS50_RR) and RS pts (WDS50_RS). The dose-modifying factor (DMF) is the ratio of WDS50_RS/WDS50_RR. It measures the horizontal shift of the dose-response curve when comparing RS vs. RR pts.

RESULTS

We scored G2+ and G3+ MUC in 80 and 41 pts; G2+ and G3+ DYS in 73 and 35 pts. The average concentration of pATM was 57.4ng/mL (sd 22.3ng/mL): 53/101 pts were classified as RS for G2+ toxicity and 35/101 as RS for G3+. On the whole cohort, the RADIODTECT© did not significantly associate with the risk of toxicity. However, we found two different dose-response curves at low WDS. There, the intrinsic biological sensitivity significantly affects the toxicity probability: ORs for RADIODTECT© are 2.6/2.4 for G2+/G3+ DYS, 6.4/2.9 for G2+/G3+ MUC. Furthermore, the difference in the incidence of side effects in RR vs. RS pts decreases as the WDS increases, reaching a region where the doses of OARs play a significant role. When combined with WDS, the RADIODTECT© effectively predicted RS pts, with DMF ranging from 0.77 for G3+ DYS to 0.40 for G2+ MUC.

CONCLUSION

These findings support the hypothesis that dose and biomarkers act synergistically; biologically based radiosensitivity plays a significant role when OARs are exposed at lower doses, while high doses of OARs determine toxicity irrespective of the underlying single pt biological characterization.

Posterior fossa ependymoma in children: A long-term single-center experience

INTRODUCTION

Ependymomas in the posterior fossa have poor prognosis. This study reports a single-center pediatric series, focusing on the value of surgical resection.

MATERIAL AND METHODS

A single-center retrospective study included all patients operated on by the senior author (CM) for posterior fossa ependymoma from 2002 to 2018. Medical and surgical data were extracted from the hospital's medical database.

RESULTS

Thirty-four patients were included. Age ranged from 6 months to 18 years, with a median of 4.7 years. Fourteen patients underwent initial endoscopic third ventriculocisternostomy before the direct surgical resection. Surgical removal was complete in 27 patients. There were 32 surgeries for second-look, local recurrence or metastasis despite complementary chemotherapy and/or radiotherapy. Twenty patients were WHO grade 2 and 14 grade 3. Sixteen patients showed recurrence (47%). Overall survival was 61.8% at a mean 10.1 years' follow-up. Morbidities comprised facial nerve palsy, swallowing disorder, and transient cerebellar syndrome. Fifteen patients had normal schooling, 6 had special assistance; 4 patients reached university, 3 of whom experienced difficulties. Three patients had a job.

CONCLUSION

Posterior fossa ependymomas are aggressive tumors. Complete surgical removal is the most important prognostic factor, despite risk of sequelae. Complementary treatment is mandatory, but no targeted therapy has so far proved effective. It is important to continue the search for molecular markers in order to improve outcomes.

Erythrocyte type 1 equilibrative nucleoside transporter expression in sickle cell disease and sickle cell trait

Hypoxia-mediated red blood cell (RBC) sickling is central to the pathophysiology of sickle cell disease (SCD). The signalling nucleoside adenosine is thought to play a significant role in this process. This study investigated expression of the erythrocyte type 1 equilibrative nucleoside transporter (ENT1), a key regulator of plasma adenosine, in adult patients with SCD and carriers of sickle cell trait (SCT). Relative quantitative expression analysis of erythrocyte ENT1 was carried out by Western blot and flow cytometry. Patients with SCD with steady state conditions, either with SS or SC genotype, untreated or under hydroxycarbamide (HC) treatment, exhibited a relatively high variability of erythrocyte ENT1, but with levels not significantly different from normal controls. Most strikingly, expression of erythrocyte ENT1 was found to be significantly decreased in patients with SCD undergoing painful vaso-occlusive episode and, unexpectedly, also in healthy SCT carriers. Promoting hypoxia-induced adenosine signalling, the reduced expression of erythrocyte ENT1 might contribute to the pathophysiology of SCD and to the susceptibility of SCT individuals to altitude hypoxia or exercise to exhaustion.

Platelet caspase-1 and Bruton tyrosine kinase activation in patients with COVID-19 is associated with disease severity and reversed in vitro by ibrutinib

Background

Severity of coronavirus disease 2019 (COVID-19) is often associated with thrombotic complications and cytokine storm leading to intensive are unit (ICU) admission. Platelets are known to be responsible for abnormal hemostasis parameters (thrombocytopenia, raised D-dimers, and prolonged prothrombin time) in other viral infections through the activation of the nucleotide-binding domain leucine repeat rich containing protein 3 inflammasome induced by signaling pathways driven by Bruton tyrosine kinase (BTK) and leading to caspase-1 activation.

Objectives

We hypothesized that caspase-1 activation and the phosphorylation of BTK could be associated with the severity of the disease and that ibrutinib, a BTK inhibitor, could inhibit platelet activation.

Methods and Results

We studied caspase-1 activation by flow cytometry and the phosphorylation of BTK by Western blot in a cohort of 51 Afro-Carribean patients with COVID-19 disease (19 not treated in ICU and 32 treated in ICU). Patients with a platelet count of 286.7 × 10⁹/L (69-642 × 10⁹/L) were treated by steroids and heparin preventive anticoagulation. Caspase-1 and BTK activation were associated with the severity of the disease and with the procoagulant state of the patients. Furthermore, we showed in vitro that the plasma of ICU patients with COVID-19 was able to increase CD62P expression and caspase-1 activity of healthy platelets and that ibrutinib could prevent it.

Conclusions

Our results show that caspase-1 and BTK activation are related to disease severity and suggest the therapeutic hope raised by ibrutinib in the treatment of COVID-19 by reducing the procoagulant state of the patients.

Plasma microparticles of intubated COVID-19 patients cause endothelial cell death, neutrophil adhesion and netosis, in a phosphatidylserine-dependent manner

COVID-19 urges scientists to better describe its pathophysiology to find new therapeutic approaches. While risk factors such as ageing, obesity and diabetes mellitus suggest a central role of endothelial cells (ECs), autopsies revealed clots in the pulmonary microvasculature, which are rich in neutrophils and DNA traps produced by these cells and called NETs. Moreover, submicron extracellular vesicles called microparticles (MPs), are described in several diseases as involved in pro-inflammatory pathways. Therefore, we analyzed 3 patient groups: one for which intubation was not necessary, an intubated group, and the last one after extubating. In the most severe group, the intubated group, platelet-derived MPs and endothelial cell-derived MPs exhibited increased concentration and size, when compared to uninfected controls. MPs of intubated COVID-19 patients triggered ECs death and overexpression of two adhesion molecules: P-selectin and VCAM-1. Strikingly, neutrophils adhesion and NET production were increased following incubation with these ECs. Importantly, we also showed that preincubation of these COVID-19 MPs with the phosphatidylserine capping endogenous protein annexin A5, abolished cytotoxicity, P-selectin and VCAM-1 induction, all like increases in neutrophil adhesion and NET release. Altogether our results unveil that MPs are a key actor in COVID-19 pathophysiology and point towards a potential therapeutic: annexin A5.

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.

Discontinuous stereotactic body radiotherapy schedule increases overall survival in early-stage non-small cell lung cancer

OBJECTIVES

The duration of stereotactic body radiotherapy (SBRT) for early-stage non-small cell lung cancer (NSCLC) may affect patient outcomes. We aimed to determine the impact of a continuous versus discontinuous SBRT schedule on local control (LC) and overall survival (OS) in NSCLC patients.

MATERIALS AND METHODS

Consecutive NSCLC stage I patients (475) treated with SBRT in four centers were retrospectively analyzed. The delivered dose ranged from 48 to 75 Gy in 3-10 fractions. Based on the ratio between the treatment duration (TD) and number of fractions (n), patients were divided into two groups: continuous schedule (CS) (TD ≤ 1.6n; 239 patients) and discontinuous schedule (DS) (TD > 1.6n; 236 patients). LC and OS were compared using Cox regression analyses after propensity score matching (216 pairs).

RESULTS

The median follow-up period was 41 months. Multivariate analysis showed that the DS (hazard ratio (HR): 0.42; 95 % confidence interval (CI): 0.22-0.78) and number of fractions (HR: 1.24; 95 % CI: 1.07-1.43) were significantly associated with LC. The DS (HR: 0.67; 95 % CI: 0.51-0.89), age (HR: 1.02; 95 % CI: 1-1.03), WHO performance status (HR: 2.27; 95 % CI: 1.39-3.7), and T stage (HR: 1.4; 95 % CI: 1.03-1.87) were significantly associated with OS. The 3-year LC and OS were 92 % and 64 % and 81 % and 53 % for DS and CS treatments, respectively (p < 0.01). Cox analysis confirmed that the discontinuous SBRT schedule significantly increased LC and OS.

CONCLUSION

DS is associated with significantly improved LC and OS in early-stage NSCLC patients treated with SBRT.

Immune checkpoint inhibitor treatment of a first cancer is associated with a decreased incidence of second primary cancer

Background

Second primary cancers (SPCs) are diagnosed in over 5% of patients after a first primary cancer (FPC). We explore here the impact of immune checkpoint inhibitors (ICIs) given for an FPC on the risk of SPC in different age groups, cancer types and treatments.

Patients and methods

The files of the 46 829 patients diagnosed with an FPC in the Centre Léon Bérard from 2013 to 2018 were analyzed. Structured data were extracted and electronic patient records were screened using a natural language processing tool, with validation using manual screening of 2818 files of patients. Univariate and multivariate analyses of the incidence of SPC according to patient characteristics and treatment were conducted.

Results

Among the 46 829 patients, 1830 (3.9%) had a diagnosis of SPC with a median interval of 11.1 months (range 0-78 months); 18 128 (38.7%) received cytotoxic chemotherapy (CC) and 1163 (2.5%) received ICIs for the treatment of the FPC in this period. SPCs were observed in 7/1163 (0.6%) patients who had received ICIs for their FPC versus 437/16 997 (2.6%) patients receiving CC and no ICIs for the FPC versus 1386/28 669 (4.8%) for patients receiving neither CC nor ICIs for the FPC. This reduction was observed at all ages and for all histotypes analyzed. Treatment with ICIs and/or CC for the FPC are associated with a reduced risk of SPC in multivariate analysis.

Conclusion

Immunotherapy with ICIs alone and in combination with CC was found to be associated with a reduced incidence of SPC for all ages and cancer types.

•

From 2013 to 2018, 3.9% of the 46 829 patients diagnosed with a first cancer presented with an SPC.

•

Treatment of the first cancer with ICIs was associated with a major reduction of SPC.

•

CC given for an FPC was also associated with a lower magnitude of reduction of SPC.

•

There were no SPC in cancer patients treated with ICIs in the localized phase of their first cancer.

Mid-position treatment strategy for locally advanced lung cancer: a dosimetric study

OBJECTIVE

The internal target volume (ITV) strategy generates larger planning target volumes (PTVs) in locally advanced non-small cell lung cancer (LA-NSCLC) than the Mid-position (Mid-p) strategy. We investigated the benefit of the Mid-p strategy regarding PTV reduction and dose to the organs at risk (OARs).

METHODS

44 patients with LA-NSCLC were included in a randomized clinical study to compare ITV and Mid-p strategies. GTV were delineated by a physician on maximum intensity projection images and on Mid-p images from four-dimensional CTs. CTVs were obtained by adding 6 mm uniform margin for microscopic extension. CTV to PTV margins were calculated using the van Herk's recipe for setup and delineation errors. For the Mid-p strategy, the mean target motion amplitude was added as a random error. For both strategies, three-dimensional conformal plans delivering 60-66 Gy to PTV were performed. PTVs, dose-volume parameters for OARs (lung, esophagus, heart, spinal cord) were reported and compared.

RESULTS

With the Mid-p strategy, the median of volume reduction was 23.5 cm3 (p = 0.012) and 8.8 cm3 (p = 0.0083) for PTVT and PTVN respectively; the median mean lung dose reduction was 0.51 Gy (p = 0.0057). For 37.1% of the patients, delineation errors led to smaller PTV with the ITV strategy than with the Mid-p strategy.

CONCLUSION

PTV and mean lung dose were significantly reduced using the Mid-p strategy. Delineation uncertainty can unfavorably impact the advantage.

ADVANCES IN KNOWLEDGE

To the best of our knowledge, this is the first dosimetric comparison study between ITV and Mid-p strategies for LA-NSCLC.

Combined therapy in children and adolescents with classical Hodgkin's lymphoma: A report from the SFCE on MDH-03 national guidelines

Hodgkin's lymphoma (HL) in children and adolescents is highly curable, but children are at risk of long-term toxicity. The MDH-03 guidelines were established in order to decrease the burden of treatment in good-responder patients, and this report should be considered a step toward further optimization of treatment within large collaborative trials. We report the therapy and long-term outcomes of 417 children and adolescents treated according to the national guidelines, which were applied between 2003 and 2007 in France. The patients were stratified into three groups according to disease extension. Chemotherapy consisted of four cycles of VBVP (vinblastine, bleomycin, VP16, prednisone) in localized stages (G1/95 pts/23%), four cycles of COPP/ABV (cyclophosphamide, vincristine, procarbazine, prednisone, adriamycin, bleomycin, vinblastine) cycles in intermediate stages (G2/184 pts/44%) and three cycles of OPPA (vincristine, procarbazine, prednisone, adriamycin) plus three cycles of COPP in advanced stages (G3/138 pts/33%). Radiation therapy of the involved field was given to 97% of the patients, with the dose limited to 20 Gy in good responders (88%). With a median follow-up of 6.6 years, the 5-year event-free survival (EFS) and overall survival (OS) were 86.7% (83.1-89.7%) and 97% (94.5-98.1%), respectively. EFS and OS for G1, G2, and G3 were 98% and 100%, 81% and 97%, and 87% and 95%, respectively. Low-risk patients treated without alkylating agents and anthracycline had excellent outcomes and a low expected incidence of late effects. Intensification with a third OPPA cycle in high-risk group patients, including stage IV patients, allowed for very good outcomes, without increased toxicity.

[French organization of paediatric radiation treatment: Results of a survey conducted by the radiotherapy Committee of the French Society of Paediatric Cancers (SFCE)]

PURPOSE

Radiotherapy is a rare indication in paediatric oncology, with 800 to 900 children in treatment per year in France. Child cancers represent approximately 1% of cancers in France and half occur before the age of 5 years. Paediatric radiation requires appropriate tools, local, time and specific training. In France, in 2015, 18 centres are accredited by the French National Cancer Institute (INCa) for this activity.

MATERIAL AND METHODS

Survey conducted in February 2015 on the care of children (0 to 18 years) in radiotherapy departments in France. The survey was sent to the radiation oncologists involved in the 18 centres. The questions concerned the qualitative and quantitative aspect, medical and organizational aspects, and the involvement of assistant practitioners in the management of this activity.

RESULTS

Seventeen centres responded. In 2014, 889 children under 18 were treated in radiotherapy departments. These departments are working together with one to four paediatric oncology departments. Regarding access to general anaesthesia: three centres perform one to seven treatment(s) under anaesthesia per year, three centres eight to ten treatments under anaesthesia per year, three centres ten to 24 treatments under anaesthesia per year and nine centres out of 17 use hypnosis techniques. In terms of human resources, in 2015, 29 radiation therapists have a paediatric radiotherapy activity. Involvement of assistant practitioners is growing and specific training are desired. Regarding treatment preparation and delivery, 13 centres have specific paediatric contentions, 14 of 16 centres employ radiation intensity modulated if dosimetry is more satisfying with 11 regularly to the craniospinal irradiation. Radiotherapy on moving areas with respiratory gating or hypofractionation is under developed.

CONCLUSION

Paediatric radiation therapy is a specific activity requiring a dedicated management, both in human, organizational, medical and scientific aspects.

[Which dose constraints on which critical organs in paediatric radiation therapy?]

Cancers in childhood are rare, representing 1% of all the cancers in developing countries. On the whole, the overall survival approaches 75% at 5 years. The radiation dose decrease in lots of indications as well as better optimized planning treatments lead to decrease the long-term toxicities in some indications. However, the radiation toxicity remains frequent, often specific of pediatric situations. Long-term toxicities are mainly neurologic, sensitive, endocrine, or linked to growth impairment (bones or muscular). Radio-induced second-cancers are also frequent after a long follow-up after cancer in childhood but will not be discussed here. Doses to critical organs as well as the most frequent radio-induced late-effects will be discussed in this paper.

Controlling the spin of co atoms on pt(111) by hydrogen adsorption

We investigate the effect of H adsorption on the magnetic properties of individual Co atoms on Pt(111) with scanning tunneling microscopy. For pristine Co atoms, we detect no inelastic features in the tunnel spectra. Conversely, CoH and CoH2 show a number of low-energy vibrational features in their differential conductance identified by isotope substitution. Only the fcc-adsorbed species present conductance steps of magnetic origin, with a field splitting identifying their effective spin as Seff=2 for CoH and 3/2 for CoH2. The exposure to H2 and desorption through tunnel electrons allow the reversible control of the spin in half-integer steps. Because of the presence of the surface, the hydrogen-induced spin increase is opposite to the spin sequence of CoHn molecules in the gas phase.