Target volume delineation for radiotherapy of meningiomas: an ANOCEF consensus guideline

PURPOSE

Radiotherapy is, with surgery, one of the main therapeutic treatment strategies for meningiomas. No prospective study has defined a consensus for the delineation of target volumes for meningioma radiotherapy. Therefore, target volume definition is mainly based on information from retrospective studies that include heterogeneous patient populations. The aim is to describe delineation guidelines for meningioma radiotherapy as an adjuvant or definitive treatment with intensity-modulated radiation therapy and stereotactic radiation therapy techniques. This guideline is based on a consensus endorsed by a multidisciplinary group of brain tumor experts, members of the Association of French-speaking Neuro-oncologists (ANOCEF).

MATERIALS AND METHODS

A 3-step procedure was used. First, the steering group carried out a comprehensive review to identify divergent issues on meningiomas target volume delineation. Second, an 84-item web-questionnaire has been developed to precisely define meningioma target volume delineation in the most common clinical situations. Third, experts members of the ANOCEF were requested to answer. The first two rounds were completed online. A third round was carried out by videoconference to allow experts to debate and discuss the remaining uncertain questions. All questions remained in a consensus.

RESULTS

Limits of the target volume were defined using visible landmarks on computed tomography and magnetic resonance imaging, considering the pathways of tumor extension. The purpose was to develop clear and precise recommendations on meningiomas target volumes.

CONCLUSION

New recommendations for meningiomas delineation based on simple anatomic boundaries are proposed by the ANOCEF. Improvement in uniformity in target volume definition is expected.

Radiotherapy of skin adnexal carcinoma

Skin adnexal carcinomas are rare skin cancer, developing from pilosebaceous, eccrine and apocrine unit. Treatment of localised tumours usually includes surgery and radiotherapy. Indications and modalities of radiotherapy depend on the pathological subtype with a lack of consensus for some histologies. This review summarises the place of radiotherapy in terms of indication, dose and fractionation, volumes to irradiate and discuss ongoing studies.

How can we consider variable RBE and LETd prediction during clinical practice? A pediatric case report at the Normandy Proton Therapy Centre using an independent dose engine

Background

To develop an auxiliary GPU-accelerated proton therapy (PT) dose and LET_d engine for the IBA Proteus®ONE PT system. A pediatric low-grade glioma case study is reported using FRoG during clinical practice, highlighting potential treatment planning insights using variable RBE dose (D_vRBE) and LET_d as indicators for clinical decision making in PT.

Methods

The physics engine for FRoG has been modified for compatibility with Proteus®ONE PT centers. Subsequently, FRoG was installed and commissioned at NPTC. Dosimetric validation was performed against measurements and the clinical TPS, RayStation (RS-MC). A head patient cohort previously treated at NPTC was collected and FRoG forward calculations were compared against RS-MC for evaluation of 3D-Γ analysis and dose volume histogram (DVH) results. Currently, treatment design at NPTC is supported with fast variable RBE and LET_d calculation and is reported in a representative case for pediatric low-grade glioma.

Results

Simple dosimetric tests against measurements of iso-energy layers and spread-out Bragg Peaks in water verified accuracy of FRoG and RS-MC. Among the patient cohort, average 3D-Γ applying 2%/2 mm, 3%/1.5 mm and 5%/1 mm were > 97%. DVH metrics for targets and OARs between FRoG and RayStation were in good agreement, with ∆D_50,CTV and ∆D_2,OAR both ⪅1%. The pediatric case report demonstrated implications of different beam arrangements on D_vRBE and LET_d distributions. From initial planning in RayStation sharing identical optimization constraints, FRoG analysis led to plan selection of the most conservative approach, i.e., minimized D_vRBE,max and LET_d,max in OARs, to avoid optical system toxicity effects (i.e., vision loss).

Conclusion

An auxiliary dose calculation system was successfully integrated into the clinical workflow at a Proteus®ONE IBA facility, in excellent agreement with measurements and RS-MC. FRoG may lead to further insight on D_vRBE and LET_d implications to help clinical decision making, better understand unexpected toxicities and establish novel clinical procedures with metrics currently absent from the standard clinical TPS.

Prospective Assessment of Early Proton Therapy-Induced Optic Neuropathy in Patients With Intracranial, Orbital or Sinonasal Tumors: Impact of A Standardized Ophthalmological Follow Up

PURPOSE

Proton therapy (PT) can be a good option to achieve tumor control while reducing the probability of radiation induced toxicities compared to X-ray-based radiotherapy. However, there are still uncertainties about the effects of PT on the organs in direct contact with the irradiated volume. The aim of this prospective series was to report 6-month follow-up of clinical and functional optic neuropathy rates of patients treated by proton therapy using a standardized comprehensive optic examination.

METHODS AND MATERIALS

Standardized ophthalmological examinations were performed to analyze subclinical anomalies in a systematic way before treatment and 6 months after the end of proton therapy with: Automatic visual field, Visual evoked potential (VEP) and optic coherence of tomography (OCT).

RESULTS

From October 2018 to July 2020 we analyzed 81 eyes. No significant differences were found in the analysis of the clinical examination of visual functions by the radiation oncologist. However, considering VEP, the impairment was statistically significant for both fibers explored at 30'angle (p:0.007) and 60'angle (p <0.001). In patients with toxicity, the distance of the target volume from the optical pathways was more important with a p-value for 30'VEP at 0.035 and for 60'VEP at 0.039.

CONCLUSIONS

These results confirm uncertainties concerning relative biological effectiveness of proton therapy, linear energy transfer appears to be more inhomogeneous especially in areas close to the target volumes. The follow-up of patients after proton therapy is not an easy process to set up but it is necessary to improve our knowledges about the biological effects of proton therapy in real life. Our study which will continue during the coming years, suggests that follow-up with in-depth examinations such as VEP as a biomarker could improve the detection of early abnormalities.

Differential normal skin transcriptomic response in total body irradiated mice exposed to scattered versus scanned proton beams

Proton therapy allows to avoid excess radiation dose on normal tissues. However, there are some limitations. Indeed, passive delivery of proton beams results in an increase in the lateral dose upstream of the tumor and active scanning leads to strong differences in dose delivery. This study aims to assess possible differences in the transcriptomic response of skin in C57BL/6 mice after TBI irradiation by active or passive proton beams at the dose of 6 Gy compared to unirradiated mice. In that purpose, total RNA was extracted from skin samples 3 months after irradiation and RNA-Seq was performed. Results showed that active and passive delivery lead to completely different transcription profiles. Indeed, 140 and 167 genes were differentially expressed after active and passive scanning compared to unirradiated, respectively, with only one common gene corresponding to RIKEN cDNA 9930021J03. Moreover, protein-protein interactions performed by STRING analysis showed that 31 and 25 genes are functionally related after active and passive delivery, respectively, with no common gene between both types of proton delivery. Analysis showed that active scanning led to the regulation of genes involved in skin development which was not the case with passive delivery. Moreover, 14 ncRNA were differentially regulated after active scanning against none for passive delivery. Active scanning led to 49 potential mRNA-ncRNA pairs with one ncRNA mainly involved, Gm44383 which is a miRNA. The 43 genes potentially regulated by the miRNA Gm44393 confirmed an important role of active scanning on skin keratin pathway. Our results demonstrated that there are differences in skin gene expression still 3 months after proton irradiation versus unirradiated mouse skin. And strong differences do exist in late skin gene expression between scattered or scanned proton beams. Further investigations are strongly needed to understand this discrepancy and to improve treatments by proton therapy.

Phase 1 trial of ralimetinib (LY2228820) with radiotherapy plus concomitant temozolomide in the treatment of newly diagnosed glioblastoma

BACKGROUND AND PURPOSE

This phase 1 trial aimed to determine the maximum tolerated dose (MTD; primary objective) of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients.

MATERIALS AND METHODS

The study was designed as an open-label dose-escalation study driven by a Tite-CRM design and followed by an expansion cohort. Ralimetinib was administered orally every 12 h, 7 days a week, for 2 cycles of 2 weeks at a dose of 100, 200 or 300 mg/12 h. Patients received ralimetinib added to standard concurrent RT (60 Gy in 30 fractions) with TMZ (75 mg/m²/day) and 6 cycles of adjuvant TMZ (150-200 mg/m² on days 1-5 every 28 days).

RESULTS

The MTD of ralimetinib was 100 mg/12 h with chemoradiotherapy. The three patients treated at 200 mg/12 h presented a dose-limiting toxicity: one patient had a grade 3 face edema, and two patients had a grade 3 rash and grade 3 hepatic cytolysis (66%). Of the 18 enrolled patients, 15 received the MTD of ralimetinib. At the MTD, the grade ≥ 3 adverse events during concomitant chemoradiotherapy were hepatic cytolysis (2/15 patients), dermatitis/rash (1/15), lymphopenia (1/15) and nausea/vomiting (1/15). No interaction of TMZ and ralimetinib when administrated concomitantly has been observed. Inhibition of pMAPKAP-K2 (-54%) was observed in peripheral blood mononuclear cells.

CONCLUSION

This phase 1 trial is the first trial to study the combination of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients. The MTD of ralimetinib was 100 mg/12 h. The most frequent dose-limiting toxicities were hepatic cytolysis and rash.

The Possibility of Using Genotoxicity, Oxidative Stress and Inflammation Blood Biomarkers to Predict the Occurrence of Late Cutaneous Side Effects after Radiotherapy

Despite the progresses performed in the field of radiotherapy, toxicity to the healthy tissues remains a major limiting factor. The aim of this work was to highlight blood biomarkers whose variations could predict the occurrence of late cutaneous side effects. Two groups of nine patients treated for Merkel Cell Carcinoma (MCC) were established according to the grade of late skin toxicity after adjuvant irradiation for MCC: grade 0, 1 or 2 and grade 3 or 4 of RTOG (Radiation Therapy Oncology Group)/EORTC (European Organization for Research and Treatment of Cancer). To try to discriminate these 2 groups, biomarkers of interest were measured on the different blood compartments after ex vivo irradiation. In lymphocytes, cell cycle, apoptosis and genotoxicity were studied. Oxidative stress was evaluated by the determination of the erythrocyte antioxidant capacity (superoxide dismutase, catalase, glutathione peroxidase, reduced and oxidized glutathione) as well as degradation products (protein carbonylation, lipid peroxidation). Inflammation was assessed in the plasma by the measurement of 14 cytokines. The most radiosensitive patients presented a decrease in apoptosis, micronucleus frequency, antioxidant enzyme activities, glutathione and carbonyls; and an increase in TNF-a (Tumor Necrosis Factor a), IL-8 (Interleukin 8) and TGF-β1 (Transforming Growth Factor β1) levels. These findings have to be confirmed on a higher number of patients and before radiotherapy and could allow to predict the occurrence of late skin side effects after radiotherapy.

Stereotactic radiotherapy on brain metastases with recent hemorrhagic signal: STEREO-HBM, a two-step phase 2 trial

BACKGROUND

Brain metastases often occur in cancer evolution. They are not only responsible for death but also for disorders affecting the quality of life and the cognitive functions. Management of brain metastases usually consists in multi-modality treatments, including neurosurgery, whole brain radiotherapy (WBRT), and more recently radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT), systemic treatment (chemotherapy or targeted therapy), combined or not with corticosteroids. Almost 20% of brain metastases can present recent (within 15 days) bleeding signs on neuro-imagery. In these conditions, WBRT is the usual treatment. Yet, patients may benefit from a more aggressive strategy with SRT or FSRT. However, these options were suspected to possibly major the risk of brain haemorrhage, although no scientifically proven. Radiation oncologists therefore usually remain reluctant to deliver SRS/FSRT for bleeding brain metastases. It is therefore challenging to establish a standard of care for the treatment of bleeding brain metastases. We propose a phase II trial to simultaneously assess safety and efficacy of FSRT to manage brain metastases with hemorrhagic signal.

METHODS

The STEREO-HBM study is a multicenter two-step non-randomised phase II trial addressing patients with at least one bleeding brain metastasis out of a maximum of 3 brain metastases. Each brain metastasis will be treated with 30 Gy in 3 fractions for 1 week. The main endpoint is based on both safety and efficacy endpoints as proposed by Bryant and Day's design. Safety endpoint is defined as the rate of bleeding complications 4 months post-FSRT while efficacy endpoint is defined as the 6-month local control rate. Multi-modal MRI will be used to assess intra-tumoral hemorrhagic events before and after treatment. Patients' quality of life will also be assessed.

DISCUSSION

Management of bleeding brain metastases is still debated and poorly explored in clinical trials. There is sparse and weak data on the signification of pretreatment intra-tumour haemorrhagic signs or on the risk of brain bleeding complications after FSRT. We expect this first prospective phase 2 trial in this particular setting will allow to clarify the place of FSRT to optimally manage bleeding brain metastases.

TRIAL REGISTRATION

NCT03696680, registered October, 4, 2018.

PROTOCOL VERSION

Version 2.1 dated from 2018/11/09.

Stereotactic ablative radiotherapy and systemic treatments for extracerebral oligometastases, oligorecurrence, oligopersistence and oligoprogression from lung cancer

Background

Stereotactic irradiation (SBRT) is a standard of care for inoperable stage I lung cancer and brain oligometastases from lung cancer but is controversial for extracranial oligometastases. We assessed outcomes of lung cancer patients with extracranial metastases in oligometastatic, oligorecurrent, oligopersistent and oligoprogressive settings (“oligometastatic spectrum”) under strategies using SBRT +/− systemic treatments.

Methods

A retrospective multicentric study of consecutive lung cancer adult patients with 1–5 extracranial metastases treated with SBRT was conducted.

Results

Of 91 patients (99 metastases, median age 63, 64.8% adenocarcinomas, 19.8% molecular alterations), 11% had oligometastases, 49.5% oligorecurrence, 19.8% oligopersistence and 19.8% oligoprogression. Of 36% of patients under systemic treatments at initiation of SBRT, systemic treatment interruption was performed in 58% of them. With median follow up of 15.3 months, crude local control at irradiated metastases was 91%, while median distant progression-free survival (dPFS) and overall survival were 6.3 and 28.4 months (2-year survival 54%). Initial nodal stage and oligometastatic spectrum were prognostic factors for dPFS; age, initial primary stage and oligometastatic spectrum were prognostic factors for survival on multivariate analysis. Patients with oncogene-addicted tumors more frequently had oligoprogressive disease. Repeat ablative irradiations were preformed in 80% of patients who had oligorelapses. Worst acute toxicities consisted of 5.5% and one late toxic death occurred.

Conclusion

The oligometastatic spectrum is a strong prognosticator in patients undergoing SBRT for extracranial metastases. Median survival was over two years but dPFS was about 6 months. Continuation of systemic therapy in oligoprogressive patients should be investigated.

P14.73 Toxicity and outcomes of reduced-dose whole brain radiotherapy as consolidation treatment for patients with CNS lymphoma in real life setting

BACKGROUND

Optimal treatment strategy for newly diagnosed primary PCNSL remains controversial. The high risk of radio-induced late-delayed neurotoxicity in patients who achieve long-term disease control constrains the use of classical consolidation WBRT. So as to reduce side cognitive effects, Morris et al, reported a phase II study, to assess the efficacy and toxicity of consolidation reduced-dose (23.4Gy) WBRT (rdWBRT) for patients with complete response after high dose methotrexate based chemotherapy. The study reported a 2-year PFS rate for these patients of 77%, with no evidence of significant cognitive decline during the follow-up (FU) period. The aim of this retrospective study was to report toxicity and outcomes of rdWBRT, in patients < 60 years old with complete response (CR) after HD-MTX based chemotherapy, in real life setting, without selection bias.

MATERIAL AND METHODS

Patients were selected from the French LOC network database, a nationwide database centralizing since 2011 information from 28 different centers in France, representing the main centers involved in PCNSL management. Patients were retrospectively selected according to the following criteria: 1) Pathological diagnosis of diffuse large B cell PCNSL; 2) age>18 and <60 years; 3) immunocompetent status; 4) First line induction treatment based on high dose MTX (At least MTX>1.5 g/m2); 5) CR according to the IPCG criteria after first-line induction treatment. Patients should have received a rdWBRT (23.4Gy in 13 fractions of 1.8Gy).

RESULTS

Twenty seven patients, were included. The median FU from initial diagnosis was 28.5 months [9.6–50.7]. Median age was 50.2 years [25–60]. Median Karnofsky Performans Status (KPS) was 90% [40–100%]. Seventeen patients had a multi focal disease at diagnosis (meningeal involvement n=6, in ophthalmic involvement n=4). PFS rates were 85% IC95[76–100 %], 65% IC95 [45–85%] and 65% IC95 [45–85%] at 1, 2, and 3 years respectively. The OS rates were 100%, 90,5% IC95 [77–100%] and 85%IC95 [69–100%]. 8 patients relapsed, with a median time from radiotherapy to recurrence of 6.5months [2.4–17]. All recurrences were outside the initially involved site(s), and 62.5% of tumors recurred as multifocal disease. All patients received salvage treatment, including intensive chemotherapy with autologous stem cell transplantation in 4 cases. No acute grade III-IV toxicity related to rdWBRT was reported. Neuropsychological follow up was available for 14 patients with no cognitive impairment at last follow up.

CONCLUSION

This is the largest retrospective study evaluating outcomes of rdWBRT for PCNSL young patients with CR after HD-MTX chemotherapy. Real life setting data from this study are quite reassuring, and rdWBRT could be considered as an efficient and safe consolidation strategy in this population. We need a longer FU to confirm the absence of cognitive deterioration.

Hypoxia Imaging and Adaptive Radiotherapy: A State-of-the-Art Approach in the Management of Glioma

Severe hypoxia [oxygen partial pressure (pO₂) below 5–10 mmHg] is more frequent in glioblastoma multiforme (GBM) compared to lower-grade gliomas. Seminal studies in the 1950s demonstrated that hypoxia was associated with increased resistance to low–linear energy transfer (LET) ionizing radiation. In experimental conditions, the total radiation dose has to be multiplied by a factor of 3 to achieve the same cell lethality in anoxic situations. The presence of hypoxia in human tumors is assumed to contribute to treatment failures after radiotherapy (RT) in cancer patients. Therefore, a logical way to overcome hypoxia-induced radioresistance would be to deliver substantially higher doses of RT in hypoxic volumes delineated on pre-treatment imaging as biological target volumes (BTVs). Such an approach faces various fundamental, technical, and clinical challenges. The present review addresses several technical points related to the delineation of hypoxic zones, which include: spatial accuracy, quantitative vs. relative threshold, variations of hypoxia levels during RT, and availability of hypoxia tracers. The feasibility of hypoxia imaging as an assessment tool for early tumor response to RT and for predicting long-term outcomes is discussed. Hypoxia imaging for RT dose painting is likewise examined. As for the radiation oncologist's point of view, hypoxia maps should be converted into dose-distribution objectives for RT planning. Taking into account the physics and the radiobiology of various irradiation beams, preliminary in silico studies are required to investigate the feasibility of dose escalation in terms of normal tissue tolerance before clinical trials are undertaken.

Efficacy and Tolerance of Post-operative Hypo-Fractionated Stereotactic Radiotherapy in a Large Series of Patients With Brain Metastases

Purpose: The aim of this study was to assess, in a large series, the efficacy and tolerance of post-operative adjuvant hypofractionated stereotactic radiation therapy (HFSRT) for brain metastases (BMs).

Materials and Methods: Between July 2012 and January 2017, 160 patients from 2 centers were operated for BM and treated by HFSRT. Patients had between 1 and 3 BMs, no brainstem lesions or carcinomatous meningitis. The primary endpoint was local control. Secondary endpoints were distant brain control, overall survival (OS) and tolerance to HFSRT.

Results: 73 patients (46%) presented with non-small cell lung cancer (NSCLC), 23 (14%) had melanoma and 21 (13%) breast cancer. Median age was 58 years (range, 22–83 years). BMs were synchronous in 50% of the cases. The most frequent prescription regimens were 24 Gy in 3 fractions (n = 52, 33%) and 30 Gy in 5 fractions (n = 37, 23%). Local control rates at 1 and 2 years were 88% [95%CI, 81–93%] and 81% [95%CI, 70–88%], respectively. Distant control rate at 1 year was 48% [95%CI, 81–93%]. In multivariate analysis, primary NSCLC was associated with a significant reduction in the risk of death compared to other primary sites (HR = 0.57, p = 0.007), the number of extra-cerebral metastatic sites (HR = 1.26, p = 0.003) and planning target volumes (HR = 1.15, p = 0.012) were associated with a lower OS. There was no prognostic factor of time to local progression. Median OS was 15.2 months [95%CI, 12.0–17.9 months] and the OS rate at 1 year was 58% [95% CI, 50–65%]. Salvage radiotherapy was administered to 72 patients (45%), of which 49 received new HFSRT. Ten (7%) patients presented late grade 2 and 4 (3%) patients late grade 3 toxicities. Thirteen (8.9%) patients developed radiation necrosis.

Conclusions: This large multicenter retrospective study shows that HFSRT allows for good local control of metastasectomy tumor beds and that this technique is well-tolerated by patients.

Phase I/IIa study of concomitant radiotherapy with olaparib and temozolomide in unresectable or partially resectable glioblastoma: OLA-TMZ-RTE-01 trial protocol

BACKGROUND

Despite multimodality treatments including neurosurgery, radiotherapy and chemotherapy, glioblastoma (GBM) prognosis remains poor. GBM is classically considered as a radioresistant tumor, because of its high local recurrence rate, inside the irradiation field. The development of new radiosensitizer is crucial to improve the patient outcomes. Pre-clinical data showed that Poly (ADP-ribose) polymerase inhibitors (PARPi) could be considered as a promising class of radiosensitizer. The aim of this study is to evaluate Olaparib, a PARPi, as radiosensitizing agent, combined with the Stupp protocol, namely temozolomide (TMZ) and intensity modulated radiotherapy (IMRT) in first line treatment of partially or non-resected GBM.

METHODS

The OLA-TMZ-RTE-01 study is a multicenter non-randomized phase I/IIa trial including unresectable or partially resectable GBM patients, from 18 to 70 years old. A two-step dose-escalation phase I design will first determine the recommended phase 2 dose (RP2D) of olaparib, delivered concomitantly with TMZ plus conventional irradiation for 6 weeks and as single agent for 4 weeks (radiotherapy period), and second, the RP2D of olaparib combined with adjuvant TMZ (maintenance period). Phase IIa will assess the 18-month overall survival (OS) of this combination. In both phase I and IIa separately considered, the progression-free survival, the objective response rate, the neurocognitive functions of patients, emotional disorders among caregivers, the survival without toxicity, degradation nor progression, the complications onset and the morphologic and functional MRI (magnetic resonance imaging) parameters will be also assessed as secondary objectives. Ancillary objectives will explore alteration of the DNA repair pathways on biopsy tumor, proton magnetic resonance spectroscopy parameters to differentiate tumor relapse and radionecrosis, and an expanded cognition evaluation. Up to 79 patients will be enrolled: 30 patients in the phase I and 49 patients in the phase IIa.

DISCUSSION

Combining PARP inhibitors, such as olaparib, with radiotherapy and chemotherapy in GBM may improve survival outcomes, while sparing healthy tissue and preserving neurocognitive function, given the replication-dependent efficacy of olaparib, and the increased PARP expression in GBM as compared to non-neoplastic brain tissue. Ancillary studies will help to identify genetic biomarkers predictive of PARPi efficacy as radiosensitizer.

TRIAL REGISTRATION

NCT03212742 , registered June, 7, 2017. Protocol version: Version 2.2 dated from 2017/08/18.

Combining PARP inhibition, radiation, and immunotherapy: A possible strategy to improve the treatment of cancer?

Immunotherapy has revolutionized the practice of oncology, improving survival in certain groups of patients with cancer. Immunotherapy can synergize with radiation therapy, increase locoregional control, and have abscopal effects. Combining it with other treatments, such as targeted therapies, is a promising means of improving the efficacy of immunotherapy. Because the value of immunotherapy is amplified with the expression of tumor antigens, coupling poly(ADP-ribose) polymerase (PARP) inhibitors and immunotherapy might be a promising treatment for cancer. Further, PARP inhibitors (PARPis) are being combined with radiation therapy to inhibit DNA repair functions, thus enhancing the effects of radiation; this association might interact with the antitumor immune response. Cytotoxic T lymphocytes are central to the antitumor immune response. PARP inhibitors and ionizing radiation can enhance the infiltration of cytotoxic T lymphocytes into the tumor bed, but they can also enhance PD-1/PDL-1 expression. Thus, the addition of immune checkpoint inhibitors with PARP inhibitors and/or ionizing radiation could counterbalance such immunosuppressive effects. With the present review article, we proposed to evaluate some of these associated therapies, and we explored the biological mechanisms and medical benefits of the potential combination of radiation therapy, immunotherapy, and PARP inhibitors.

Radiosurgery or hypofractionated stereotactic radiotherapy for brain metastases from radioresistant primaries (melanoma and renal cancer)

Background

Until 50% of patients with renal cancer or melanoma, develop brain metastases during the course of their disease. Stereotactic radiotherapy has become a standard of care for patients with a limited number of brain metastases. Given the radioresistant nature of melanoma and renal cancer, optimization of the fractionation of stereotactic radiotherapy is needed. The purpose of this retrospective study was to elucidate if hypofractionated stereotactic radiotherapy (HFSRT) impacts local control of brain metastases from radioresistant tumors such as melanoma and renal cancer, in comparison with radiosurgery (SRS).

Methods

Between 2012 and 2016, 193 metastases, smaller than 3 cm, from patients suffering from radioresistant primaries (melanoma and renal cancer) were treated with HFSRT or SRS. The primary outcome was local progression free survival (LPFS) at 6, 12 and 18 months. Overall survival (OS) and cerebral progression free survival (CPFS) were secondary outcomes, and were evaluated per patient. Objective response rate and radionecrosis incidence were also reported. The statistical analysis included a supplementary propensity score analysis to deal with bias induced by non-randomized data.

Results

After a median follow-up of 7.4 months, LPFS rates at 6, 12 and 18 months for the whole population were 83, 74 and 70%, respectively. With respect to fractionation, LPFS rates at 6, 12 and 18 months were 89, 79 and 73% for the SRS group and 80, 72 and 68% for the HFSRT group. The fractionation schedule was not statistically associated with LPFS (HR = 1.39, CI95% [0.65–2.96], p = 0.38). Time from planning MRI to first irradiation session longer than 14 days was associated with a poorer local control rate. Over this time, LPFS at 12 months was reduced from 86 to 70% (p = 0.009). Radionecrosis occurred in 7.1% for HFSRT treated metastases to 9.6% to SRS treated metastases, without any difference according to fractionation (p = 0.55). The median OS was 9.6 months. Six, 12 and 18 months CPFS rates were 54, 24 and 17%, respectively.

Conclusion

Fractionation does not decrease LPFS. Even for small radioresistant brain metastases (< 3 cm), HFSRT, with 3 or 6 fractions, leads to an excellent local control rate of 72% at 1 year with a rate of 7.1% of radionecrosis. HFSRT is a safe and efficient alternative treatment to SRS.

Electronic supplementary material

The online version of this article (10.1186/s13014-018-1083-1) contains supplementary material, which is available to authorized users.

Radiosensitization Effect of Talazoparib, a Parp Inhibitor, on Glioblastoma Stem Cells Exposed to Low and High Linear Energy Transfer Radiation

Despite continuous improvements in treatment of glioblastoma, tumor recurrence and therapy resistance still occur in a high proportion of patients. One underlying reason for this radioresistance might be the presence of glioblastoma cancer stem cells (GSCs), which feature high DNA repair capability. PARP protein plays an important cellular role by detecting the presence of damaged DNA and then activating signaling pathways that promote appropriate cellular responses. Thus, PARP inhibitors (PARPi) have recently emerged as potential radiosensitizing agents. In this study, we investigated the preclinical efficacy of talazoparib, a new PARPi, in association with low and high linear energy transfer (LET) irradiation in two GSC cell lines. Reduction of GSC fraction, impact on cell proliferation, and cell cycle arrest were evaluated for each condition. All combinations were compared with a reference schedule: photonic irradiation combined with temozolomide. The use of PARPi combined with photon beam and even more carbon beam irradiation drastically reduced the GSC frequency of GBM cell lines in vitro. Furthermore, talazoparib combined with irradiation induced a marked and prolonged G2/M block, and decreased proliferation. These results show that talazoparib is a new candidate that effects radiosensitization in radioresistant GSCs, and its combination with high LET irradiation, is promising.

A French national breast and thyroid cancer screening programme for survivors of childhood, adolescent and young adult (CAYA) cancers - DeNaCaPST programme

Background

Survival of childhood, adolescent and young adult (CAYA) cancers has increased with progress in the management of the treatments and has reached more than 80% at 5 years. Nevertheless, these survivors are at great risk of second cancers and non-malignant co-morbidities in later life. DeNaCaPST is a non-interventional study whose aim is to organize a national screening for thyroid cancer and breast cancer in survivors of CAYA cancers. It will study the compliance with international recommendations, with the aim, regarding a breast screening programme, of offering for every woman living in France, at equal risk, an equal screening.

Method

DeNaCaPST trial is coordinated by the INSERM 1018 unit in cooperation with the LEA (French Childhood Cancer Survivor Study for Leukaemia) study’s coordinators, the long term follow up committee and the paediatric radiation committee of the SFCE (French Society of Childhood Cancers).

A total of 35 centres spread across metropolitan France and la Reunion will participate. FCCSS (French Childhood Cancer Survivor Study), LEA and central registry will be interrogated to identify eligible patients. To participate, centers agreed to perform a complete “long-term follow-up consultations” according to good clinical practice and the guidelines of the SFCE (French Society of Children Cancers).

Discussion

As survival has greatly improved in childhood cancers, detection of therapy-related malignancies has become a priority even if new radiation techniques will lead to better protection for organs at risk. International guidelines have been put in place because of the evidence for increased lifetime risk of breast and thyroid cancer. DeNaCaPST is based on these international recommendations but it is important to recognize that they are based on expert consensus opinion and are supported by neither nonrandomized observational studies nor prospective randomized trials in this specific population. Over-diagnosis is a phenomenon inherent in any screening program and therefore such programs must be evaluated.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3318-1) contains supplementary material, which is available to authorized users.

[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.

Reprint of "Chordoma in children: Case-report and review of literature"

We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon-proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.

Chordoma in children: Case-report and review of literature

We report an exceptional case of a very late local failure in a 9-year-old boy presenting with a chordoma of the cranio-cervical junction. The child was initially treated with a combination of surgical resection followed by high dose photon-proton radiation therapy. This aggressive therapy allowed a 9-year remission with minimal side-effects. Unfortunately, he subsequently presented with a local failure managed with a second full-dose course of protons. The child died one year later from local bleeding of unclear etiology.

Vemurafenib and concomitant stereotactic radiation for the treatment of melanoma with spinal metastases: A case report

A 56-year-old man with BRAFV600E melanoma and spinal metastases treated with vemurafenib and stereotactic radiation showed a partial response without neurological, skin or mucosal toxicity, 8 months after completion of this combination. This case suggests that stereotactic radiation spares normal tissues and might be safer than conventional fractionated radiation with vemurafenib.

Autophagic program is regulated by miR-325

Autophagy is required for the maintenance of cardiomyocytes homeostasis. However, the abnormal autophagy could lead to the development of heart failure. Autophagy is enhanced during myocardial ischemia/reperfusion; it remains to elucidate the molecular regulation of autophagy. We report here that miR-325, ARC and E2F1 constitute an axis that regulates autophagy. Our results showed that miR-325 expression is upregulated upon anoxia/reoxygenation and ischemia/reperfusion. Cardiomyocyte-specific overexpression of the miR-325 potentiates autophagic responses and myocardial infarct sizes, whereas knockdown of miR-325 inhibited autophagy and cell death. We searched for the downstream mediator of miR-325 and identified that ARC is a target of miR-325. ARC transgenic mice could attenuate autophagy and myocardial infarction sizes upon pressure-overload-induced heart failure, whereas ARC null mice exhibited an increased autophagic accumulation in the heart. The suppression of ARC by miR-325 led to its inability to repress autophagic program. In exploring the molecular mechanism by which miR-325 expression is regulated, our results revealed that the transcription factor E2F1 contributed to promote miR-325 expression. E2F1 null mice demonstrated reduced autophagy and myocardial infarction sizes upon ischemia/reperfusion. Our present study reveals a novel autophagic regulating model that is composed of E2F1, miR-325 and ARC. Modulation of their levels may provide a new approach for tackling cardiac failure.

Value of serological tests in the diagnosis of viral acute respiratory infections in adults

The dynamics of the antibody response to influenza viruses A (H1N1), A (H3N2) and B, to parainfluenza viruses 1, 2, 3, to adenoviruses and respiratory syncytial virus was studied in paired serum samples collected from 110 patients hospitalized with acute respiratory infections (ARI) and in 40 patients suffering from other diseases. Rises in serum antibody titers to 1--5 of the above mentioned antigens were detected in many of the patients of both groups. The fact is most likely due to the presence of some epidemiologically and clinically uncharacteristic viral ARI (influenza included); simultaneous or successive infections with influenza virus and different other viruses were very frequent. A greater efficiency of the etiological diagnosis of viral ARI can be achieved only by the association of epidemiological and clinical criteria with serological data, the visualization of viral antigens and virus isolation.