Prediction of residual disease using circulating DNA detection after potentiated radiotherapy for locally advanced head and neck cancer (NeckTAR): a study protocol for a prospective, multicentre trial.

BACKGROUND: Sensitive and reproducible detection of residual disease after treatment is a major challenge for patients with locally advanced head and neck cancer. Indeed, the current imaging techniques are not always reliable enough to determine the presence of residual disease. The aim of the NeckTAR trial is to assess the ability of circulating DNA (cDNA), both tumoral and viral, at three months post-treatment, to predict residual disease, at the time of the neck dissection, among patients with partial cervical lymph node response on PET-CT, after potentiated radiotherapy. METHODS: This will be an interventional, multicentre, single-arm, open-label, prospective study. A blood sample will be screened for cDNA before potentiated radiotherapy and after 3 months if adenomegaly persists on the CT scan 3 months after the end of treatment. Patients will be enrolled in 4 sites in France. Evaluable patients, i.e. those with presence of cDNA at inclusion, an indication for neck dissection, and a blood sample at M3, will be followed for 30 months. Thirty-two evaluable patients are expected to be recruited in the study. DISCUSSION: The decision to perform neck dissection in case of persistent cervical adenopathy after radio-chemotherapy for locally advanced head and neck cancer is not always straightforward. Although studies have shown that circulating tumour DNA is detectable in a large proportion of patients with head and neck cancer, enabling the monitoring of response, the current data is insufficient to allow routine use of this marker. Our study could lead to better identification of patients who do not have residual lymph node disease in order to avoid neck dissection and preserve their quality-of-life while maintaining their prospects of survival. TRIAL REGISTRATION: Clinicaltrials.gov: NCT05710679, registered on 02/02/2023, https://clinicaltrials.gov/ct2/show/ . Identifier with the French National Agency for the Safety of Medicines and Health Products (ANSM): N°ID RCB 2022-A01668-35, registered on July 15th, 2022.

Phase I/II study testing the combination of AGuIX nanoparticles with radiochemotherapy and concomitant temozolomide in patients with newly diagnosed glioblastoma (NANO-GBM trial protocol).

BACKGROUND: Despite standard treatments including chemoradiotherapy with temozolomide (TMZ) (STUPP protocol), the prognosis of glioblastoma patients remains poor. AGuIX nanoparticles have a high radiosensitizing potential, a selective and long-lasting accumulation in tumors and a rapid renal elimination. Their therapeutic effect has been proven in vivo on several tumor models, including glioblastoma with a potential synergetic effect when combined with TMZ based chemoradiotherapy, and they are currently evaluated in 4 ongoing Phase Ib and II clinical trials in 4 indications (brain metastases, lung, pancreatic and cervix cancers) (> 100 patients received AGuIX). Thus, they could offer new perspectives for patients with newly diagnosed glioblastoma. The aim of this study is to determine the recommended dose of AGuIX as a radiosensitizer in combination with radiotherapy and TMZ during the concurrent radio-chemotherapy period for phase II (RP2D) and to estimate the efficacy of the combination. METHODS: NANO-GBM is a multicenter, phase I/II, randomized, open-label, non-comparative, therapeutic trial. According to a dose escalation scheme driven by a TITE-CRM design, 3 dose levels of AGuIX (50, 75 and 100 mg/kg) will be tested in phase I added to standard concomitant radio-chemotherapy. Patients with grade IV glioblastoma, not operated or partially operated, with a KPS ≥ 70% will be eligible for the study. The primary endpoints are i) for phase I, the RP2D of AGuIX, with DLT defined as any grade 3-4 NCI-CTCAE toxicity and ii) for phase II, the 6-month progression-free survival rate. The pharmacokinetics, distribution of nanoparticles, tolerance of the combination, neurological status, overall survival (median, 6-month and 12-month rates), response to treatment, and progression-free survival (median and 12-month rates) will be assessed as secondary objectives. Maximum sixty-six patients are expected to be recruited in the study from 6 sites. DISCUSSION: The use of AGuIX nanoparticles could allow to overpass the radioresistance to the reference treatment of newly diagnosed glioblastomas that have the poorest prognosis (incomplete resection or biopsy only). TRIAL REGISTRATION: Clinicaltrials.gov: NCT04881032 , registered on April 30, 2021. Identifier with the French National Agency for the Safety of Medicines and Health Products (ANSM): N°Eudra CT 2020-004552-15. PROTOCOL: version 3, 23 May 2022.

Transcriptional alterations in glioma result primarily from DNA methylation-independent mechanisms.

In cancer cells, aberrant DNA methylation is commonly associated with transcriptional alterations, including silencing of tumor suppressor genes. However, multiple epigenetic mechanisms, including polycomb repressive marks, contribute to gene deregulation in cancer. To dissect the relative contribution of DNA methylation-dependent and -independent mechanisms to transcriptional alterations at CpG island/promoter-associated genes in cancer, we studied 70 samples of adult glioma, a widespread type of brain tumor, classified according to their isocitrate dehydrogenase (IDH1) mutation status. We found that most transcriptional alterations in tumor samples were DNA methylation-independent. Instead, altered histone H3 trimethylation at lysine 27 (H3K27me3) was the predominant molecular defect at deregulated genes. Our results also suggest that the presence of a bivalent chromatin signature at CpG island promoters in stem cells predisposes not only to hypermethylation, as widely documented, but more generally to all types of transcriptional alterations in transformed cells. In addition, the gene expression strength in healthy brain cells influences the choice between DNA methylation- and H3K27me3-associated silencing in glioma. Highly expressed genes were more likely to be repressed by H3K27me3 than by DNA methylation. Our findings support a model in which altered H3K27me3 dynamics, more specifically defects in the interplay between polycomb protein complexes and the brain-specific transcriptional machinery, is the main cause of transcriptional alteration in glioma cells. Our study provides the first comprehensive description of epigenetic changes in glioma and their relative contribution to transcriptional changes. It may be useful for the design of drugs targeting cancer-related epigenetic defects.

Preoperative stereotactic radiosurgery for brain metastases: the STEP study protocol for a multicentre, prospective, phase-II trial.

BACKGROUND: Surgery is an important therapeutic option for brain metastases. Currently, postoperative stereotactic radiosurgery (SRT) leads to 6-month and 1-year local control estimated at 70 and 62% respectively. However, there is an increased risk of radio-necrosis and leptomeningeal relapse. Preoperative SRT might be an alternative, providing local control remains at least equivalent. It is an innovative concept that could enable the stereotactic benefits to be retained with advantages over post-operative SRT. METHODS: STEP has been designed as a national, multicentre, open-label, prospective, non-randomized, phase-II trial. Seventeen patients are expected to be recruited in the study from 7 sites and they will be followed for 12 months. Patients with more than 4 distinct brain metastases, including one with a surgical indication, and an indication for SRT and surgery, are eligible for enrolment. The primary objective of the trial is to assess 6-month local control after preoperative SRT. The secondary objectives include the assessment of local control, radio-necrosis, overall survival, toxicities, leptomeningeal relapse, distant control, cognitive function, and quality of life. The experimental design is based on a Flemming plan. DISCUSSION: There is very little data available in the literature on preoperative SRT: there have only been 3 American single or two-centre retrospective studies. STEP is the first prospective trial on preoperative SRT in Europe. Compared to postoperative stereotactic radiotherapy, preoperative stereotactic radiotherapy will enable reduction in the irradiated volume, leptomeningeal relapse and the total duration of the combined treatment (from 4 to 6 weeks to a few days). TRIAL REGISTRATION NUMBER: Clinicaltrials.gov: NCT04503772 , registered on August 07, 2020. Identifier with the French National Agency for the Safety of Medicines and Health Products (ANSM): N°ID RCB 2020-A00403-36, registered in February 2020. PROTOCOL: version 4, 07 December 2020.

Predictive factors of toxicity of TPF induction chemotherapy for locally advanced head and neck cancers.

BACKGROUND: The rate of toxic deaths related to induction chemotherapy in the treatment of locally advanced head and neck cancers is unacceptable and calls into question this therapeutic strategy, which is however highly effective in terms of rate and speed of response. The purpose of the study was to investigate predictive factors of toxicity of induction chemotherapy with docetaxel, cisplatin, and 5-fluorouracil (TPF) in locally advanced head and neck cancers (LAHNC). METHODS: Between June 2009 and December 2017, 113 patients treated consecutively with TPF were included retrospectively. Patients were receiving induction chemotherapy for either an inoperable cancer or laryngeal preservation. For inoperable cancer, induction chemotherapy was proposed to patients presenting either a large tumor with strong symptoms (dyspnea, dysphagia, pain) or a tumor with rapid progression. Risk factors were chosen among the initial patient and tumour characteristics and chemotherapy modalities. RESULTS: Eighty-nine patients (79%) were male; the median age was 58 years [32-71]. Sixty-nine (61%) patients were treated for inoperable cancer and 44 (39%) for laryngeal preservation. 45% had stage IVa cancer, 28% stage III and 25% stage IVb. Sixty percent of patients had a partial response after TPF, 22% had a complete response, 12% were stable, 5% were progressing, and 1% had a discordant response. Thirty-four patients (30%) received enteral feeding during induction chemotherapy with TPF. The possibility of oral feeding without a tube was predictive of a better response (p = 0.003). Seven (6%) patients died during TPF. There was an increased risk of death with preexisting liver dysfunction (liver dysmorphia on imaging or decrease prothrombin rate) (p = 0.032). There was an increased risk of grade ≥ 3 infection if an enteral feeding occurred during the period of induction chemotherapy (p = 0.03). CONCLUSIONS: TPF induction chemotherapy had an 82% objective response rate with 6% toxic deaths. Nutritional status and the presence of hepatic dysfunction are significant risk factors to be taken into account in therapeutic decisions.

Combining immunotherapy and radiotherapy in head and neck squamous cell cancers: which perspectives?

PURPOSE OF REVIEW: The role of the immune system is important in both initiation and development of head and neck cancers. Various immune checkpoints have been discovered that can be exploited by cancer to evade immune mediated destruction. Therefore, immune checkpoint inhibitors have been developed to overcome cancer immune-evasion and are currently in clinical use in head and neck cancers. In addition, the immune system appears to play an important role in the response to radiotherapy. The combination of immunotherapy with radiotherapy may increase the ability to induce immunogenic death by removing the locks blocking the immune system. RECENT FINDINGS: Although the antitumour efficacy of radiotherapy is based primarily on the toxicity of DNA damage, studies have suggested that this efficacy is based not only on this local cytotoxic and antiproliferative effect, but also on the interactions between the tumor and its microenvironment that are altered. Thus, the cytotoxic action of radiotherapy on tumor cells provides T lymphocytes with tumor neoantigens, and releases proinflammatory cytokines that promote the immune response. Cell death inducing this type of immune response is called immunogenic death. Therefore, several phase 3 clinical trials are currently ongoing evaluating the combination of radiotherapy and immune checkpoint inhibitors in head and neck cancers. SUMMARY: Combining immunotherapy and radiotherapy in head and neck cancers is promising. Several phase 3 clinical trials are ongoing that may be practice changing.

A multicenter prospective phase II study of postoperative hypofractionated stereotactic body radiotherapy (SBRT) in the treatment of early-stage oropharyngeal and oral cavity cancers with high risk margins: the STEREO POSTOP GORTEC 2017-03 trial.

BACKGROUND: Primary surgery is usually the mainstay treatment in early-stage oropharyngeal and oral cavity cancer. Typically, neck surgery is performed. Negative tumor margins are recommended (> 5 mm). If feasible, re-resection of any positive margin is preferred. Otherwise, postoperative radiotherapy is required. Adjuvant postoperative radiotherapy can be limited to the primary site for patients with pT1-T2 tumors and negative neck exploration. Currently, both fractionated external beam radiotherapy and brachytherapy can have a role in the postoperative management of early-stage oropharyngeal and oral cavity cancer with high risk margins. Another possible alternative could be postoperative stereotactic body radiotherapy (SBRT). The aim of this study is to evaluate postoperative SBRT in the treatment of early-stage oropharyngeal and oral cavity cancer with high risk margins. METHODS: The STEREO POSTOP study is a national, open-label, non-randomized phase II trial within the GORTEC network. Patients with early-stage oropharyngeal and oral cavity cancers with high risk margins indicating the need for postoperative radiation are eligible for enrollment. SBRT consists of a total dose of 36 Gy in 6 fractions over 2 weeks. The primary endpoint is severe late toxicity defined as 2-year toxicity of grade ≥ 3 according to CTCAE V4.03 classification. The secondary endpoints include acute toxicity (≤ 3 months), local and locoregional control, disease-free and overall survival, quality of life of patients, nutritional impact and predictive factors of toxicity. The experimental design chosen is a one-step Fleming plan design without interim analysis as the primary endpoint will be evaluated at a 2-year follow-up. Ninety patients will be recruited. The study was started in January 2018 with a 4-year enrollment period and an estimated completion in January 2024. DISCUSSION: This study is the first prospective trial to evaluate head and neck cancer postoperative SBRT in the setting of early-stage oropharyngeal and oral cavity cancers with high risk margins. SBRT is an attractive option because it delivers a highly conformal dose of radiation in a limited number of fractions (like brachytherapy but with less contraindication), with steep dose gradients resulting in reduced normal tissue irradiation and with a short overall treatment time. TRIAL REGISTRATION: Clinicaltrials.gov : NCT03401840 , registered on 17-1-2018. Identifier in French National Agency for the Safety of Medicines and Health Products (ANSM): N°ID - RCB 2017-A02058-45, registered on July 2017. Protocol version: Version 3 dated from 25th November 2019.

Quality of life for older patients with cancer: a review of the evidence supporting melatonin use.

PURPOSE: The proportion of older populations living with cancer is on the increase. Maintaining or improving their quality of life (QoL) has become an important goal in the treatment of cancer and has become an endpoint in clinical trials. Melatonin regulates a wide variety of physiological functions and is involved in the initiation of sleep and the improvement of QoL. With age, the secretion of melatonin decreases and could lead to a deterioration in QoL. METHODS: Literature searches were conducted using the PubMed database. The search terms and derivatives of "metastatic cancer", "older patients", "quality of life" and "melatonin" were used. Titles and abstracts were screened to identify whether studies were relevant for full-text screening. RESULTS: There is major concern about the symptoms older cancer patients encounter during treatment because they can impact their QoL. Melatonin supplementation presents several benefits for older patients: improvement in survival, decrease in symptoms induced by cancer and cancer treatment, and also improvements in quality of life. CONCLUSION: It therefore seems appropriate to study the impact of melatonin supplementation during cytotoxic therapy on QoL among elderly patients with metastatic cancer. The use of melatonin as a therapeutic strategy seems particularly suitable for elderly patients, a population known to secrete significantly less melatonin. However, to date, no studies have been conducted in this population.

Detection of the alternative lengthening of telomeres pathway in malignant gliomas for improved molecular diagnosis.

Human malignant gliomas exhibit acquisition of either one of two telomere maintenance mechanisms, resulting from either reactivation of telomerase expression or activation of an alternative lengthening of telomeres (ALT) mechanism. In the present study, we analyzed 63 human malignant gliomas for the presence of ALT-specific extrachromosomal circles of telomeric DNA (C-circles) and measured telomerase expression, telomeric DNA content (Telo/Alu method), and telomeric repeat-containing RNAs (TERRA) levels. We also assessed histomolecular markers routinely used in clinical practice. The presence of C-circles significantly correlated with IDH1/2 mutation, MGMT exon 1 methylation, low Ki-67 immunostaining, increased telomeric DNA content, absence of functional ATRX protein and level of HTERT gene expression. In multivariate analysis, we observed a trend to a correlation between elevated TERRA levels and increased survival. Interestingly, the C-circles assay allowed to detect ALT activation in glioblastomas exhibiting wild-type IDH1/2 and ATRX expression. These results suggest that, after the correlations uncovered here have been confirmed on larger numbers of tumors, telomeric markers might be useful in improving diagnosis. They also point out to the utility of using the specific, sensitive and quantitative C-circle and Telo/Alu assays that can work with as few as 30 ng of tumor DNA.

The tumoral A genotype of the MGMT rs34180180 single-nucleotide polymorphism in aggressive gliomas is associated with shorter patients' survival.

Malignant gliomas are the most common primary brain tumors. Grade III and IV gliomas harboring wild-type IDH1/2 are the most aggressive. In addition to surgery and radiotherapy, concomitant and adjuvant chemotherapy with temozolomide (TMZ) significantly improves overall survival (OS). The methylation status of the O(6)-methylguanine-DNA methyltransferase (MGMT) promoter is predictive of TMZ response and a prognostic marker of cancer outcome. However, the promoter regions the methylation of which correlates best with survival in aggressive glioma and whether the promoter methylation status predictive value could be refined or improved by other MGMT-associated molecular markers are not precisely known. In a cohort of 87 malignant gliomas treated with radiotherapy and TMZ-based chemotherapy, we retrospectively determined the MGMT promoter methylation status, genotyped single nucleotide polymorphisms (SNPs) in the promoter region and quantified MGMT mRNA expression level. Each of these variables was correlated with each other and with the patients' OS. We found that methylation of the CpG sites within MGMT exon 1 best correlated with OS and MGMT expression levels, and confirmed MGMT methylation as a stronger independent prognostic factor compared to MGMT transcription levels. Our main finding is that the presence of only the A allele at the rs34180180 SNP in the tumor was significantly associated with shorter OS, independently of the MGMT methylation status. In conclusion, in the clinic, rs34180180 SNP genotyping could improve the prognostic value of the MGMT promoter methylation assay in patients with aggressive glioma treated with TMZ.

Colorectal cancer metastasis: the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation.

PURPOSE: To assess the usefulness of combining hyperthermia with a DNA repair inhibitor (double-strand break bait [Dbait]) and its potential application to radiofrequency ablation (RFA) in a preclinical model of human colorectal cancer. MATERIALS AND METHODS: The local ethics committee of animal experimentation approved all investigations. First, the relevance was assessed by studying the survival of four human colorectal adenocarcinoma cell cultures after 1 hour of hyperthermia at 41°C or 43°C with or without Dbait. Human colon adenocarcinoma cells (HT-29) were grafted subcutaneously into nude mice (n = 111). When tumors reached approximately 500 mm(3), mice were treated with Dbait alone (n = 20), sublethal RFA (n = 21), three different Dbait schemes and sublethal RFA (n = 52), or a sham treatment (n = 18). RFA was performed to ablate the tumor center alone. To elucidate antitumor mechanisms, 39 mice were sacrificed for blinded pathologic analysis, including assessment of DNA damage, cell proliferation, and tumor necrosis. Others were monitored for tumor growth and survival. Analyses of variance and log-rank tests were used to evaluate differences. RESULTS: When associated with mild hyperthermia, Dbait induced cytotoxicity in all tested colon cancer cell lines. Sublethal RFA or Dbait treatment alone moderately improved survival (median, 40 days vs 28 days for control; P = .0005) but combination treatment significantly improved survival (median, 84 days vs 40 days for RFA alone, P = .0004), with approximately half of the animals showing complete tumor responses. Pathologic studies showed that the Dbait and RFA combination strongly enhances DNA damage and coagulation areas in tumors. CONCLUSION: Combining Dbait with RFA sensitizes the tumor periphery to mild hyperthermia and increases RFA antitumor efficacy.

Role of Akt in human malignant glioma: from oncogenesis to tumor aggressiveness.

Gathering evidence has revealed that Akt signaling pathway plays an important role in glioma progression and aggressiveness. Among Akt kinases the most studied, Akt1, has been involved in many cellular processes that are in favor of cell malignancy. More recently, the actions of the two other isoforms, Akt2 and Akt3 have emerged in glioma. After a description of Akt pathway activation, we will explore the role of each isoform in malignant glioma that strengthens the current preclinical and clinical studies evaluating the impact of Akt pathway targeting in glioblastomas.

The Recent Management of Vestibular Schwannoma Radiotherapy: A Narrative Review of the Literature.

BACKGROUND: Radiotherapy (RT) plays an important role in the therapeutic management of vestibular schwannoma (VS). Fractionated stereotactic radiotherapy (FSRT) or radiosurgery (SRS) are the two modalities available. The purpose of this article is to review the results of VS RT studies carried out over the last ten years. MATERIALS AND METHODS: A literature search was performed with PubMed and Medline by using the words vestibular schwannoma, acoustic neuroma, radiotherapy, and radiosurgery. RESULTS: In small (<3 cm) VS, SRS offers a local control rate of >90%, which seems similar to microsurgery, with a favorable tolerance profile. Hypofractionated FSRT (three to five fractions) is a relatively recent modality and has shown similar outcomes to normofractionated FSRT. Hearing preservation may highly differ between studies, but it is around 65% at 5 years. CONCLUSIONS: SRS and FRST are non-invasive treatment options for VS. SRS is often preferred for small lesions less than 3 cm, and FSRT for larger lesions. However, no randomized study has compared these modalities.

Non-invasive intracranial pressure monitoring for high-grade gliomas patients treated with radiotherapy: results of the GMaPIC trial.

Introduction: Patients with high-grade gliomas are at risk of developing increased intracranial hypertension (ICHT) in relation to the increase in volume of their tumor. ICP change cannot be measured by invasive method but can be estimated by using routine clinical signs, in combination with a standard imaging method, magnetic resonance imaging (MRI). A non-invasive monitoring of ICP could be of interest in high-grade glioma, in particular after radiotherapy treatment with as major side effect a cerebral oedema. Patients and Methods: This prospective clinical study aimed to compare the ICP changes (estimated by a non-invasive method based upon distortion product otoacoustic emissions (DPOAE) monitoring) with volume changes observed on MRI in patients with high-grade gliomas treated with radiotherapy. DPOAE measurements were performed one month after the end of radiotherapy and then every 3 months for one year. At each visit, the patient also underwent MRI as well as an evaluation of clinical signs. Results: The variation in the estimate of intracranial pressure readout measured at each follow-up visit (in absolute value with respect to the baseline measurements) was significantly associated with the variation of T2/FLAIR volume (n=125; p<0.001) with a cut off value of change ICP readout of 40.2 degrees (e.i. an estimated change of 16 mm Hg). Discussion: The GMaPIC trial confirm the hypothesis that the ICP change estimated by DPOAEs measurement using a non-invasive medical device is correlated with the change of the tumor or edema in high grade glioma after radiotherapy. The device could thus become an easy-to-use and non-invasive intracranial pressure monitoring tool for these patients. Clinical Trial Registration: Clinicaltrials.gov, identifier (NCT02520492).

Randomized phase III trial of metabolic imaging-guided dose escalation of radio-chemotherapy in patients with newly diagnosed glioblastoma (SPECTRO GLIO trial).

BACKGROUND: Glioblastoma (GBM) systematically recurs after a standard 60 Gy radio-chemotherapy regimen. Since magnetic resonance spectroscopic imaging (MRSI) has been shown to predict the site of relapse, we analyzed the effect of MRSI-guided dose escalation on overall survival (OS) of patients with newly diagnosed GBM. METHODS: In this multicentric prospective phase III trial, patients who had undergone biopsy or surgery for a GBM were randomly assigned to a standard dose (SD) of 60 Gy or a high dose (HD) of 60 Gy with an additional simultaneous integrated boost totaling 72 Gy to MRSI metabolic abnormalities, the tumor bed and residual contrast enhancements. Temozolomide was administered concomitantly and maintained for 6 months thereafter. RESULTS: One hundred and eighty patients were included in the study between March 2011 and March 2018. After a median follow-up of 43.9 months (95% CI [42.5; 45.5]), median OS was 22.6 months (95% CI [18.9; 25.4]) versus 22.2 months (95% CI [18.3; 27.8]) for HD, and median progression-free survival was 8.6 (95% CI [6.8; 10.8]) versus 7.8 months (95% CI [6.3; 8.6]), in SD versus HD, respectively. No increase in toxicity rate was observed in the study arm. The pseudoprogression rate was similar across the SD (14.4%) and HD (16.7%) groups. For O(6)-methylguanine-DNA methyltransferase (MGMT) methylated patients, the median OS was 38 months (95% CI [23.2; NR]) for HD patients versus 28.5 months (95% CI [21.1; 35.7]) for SD patients. CONCLUSION: The additional MRSI-guided irradiation dose totaling 72 Gy was well tolerated but did not improve OS in newly diagnosed GBM. TRIAL REGISTRATION: NCT01507506; registration date: December 20, 2011. https://clinicaltrials.gov/ct2/show/NCT01507506?cond=NCT01507506&rank=1.

Essential data variables for a minimum dataset for head and neck cancer trials and clinical research: HNCIG consensus recommendations and database.

The Head and Neck Cancer International Group (HNCIG) has undertaken an international modified Delphi process to reach consensus on the essential data variables to be included in a minimum database for HNC research. Endorsed by 19 research organisations representing 34 countries, these recommendations provide the framework to facilitate and harmonise data collection and sharing for HNC research. These variables have also been incorporated into a ready to use downloadable HNCIG minimum database, available from the HNCIG website.

Postoperative SBRT in the treatment of early-stage oropharyngeal and oral cavity cancers with high-risk margins: A dosimetric comparison of volumetric modulated arc therapy with or without non-coplanar arcs and acute toxicity outcomes from the STEREOPOSTOP GORTEC 2017-03 phase 2 trial.

Background and purpose: The STEREO POSTOP GORTEC 2017-03 phase 2 trial (NCT03401840) evaluates postoperative stereotactic body radiotherapy (SBRT) in case of high-risk margins for pT1-T2/N0 oropharyngeal and oral cavity tumors. The present ancillary study aimed to compare the dosimetric impact of adding non-coplanar arcs to the volumetric modulated arc therapy (VMAT) technique and to evaluate acute toxicities on the first patients included in this trial. Materials and methods: Ten patients were included. Patients were treated with Novalis TX®. The total dose was 36 Gy (100 % isodose line) in 6 fractions, treated every other day. Two treatment plans were created for each patient: one plan using 2 coplanar arcs only (VMATc) and one plan using coplanar and 3 non-coplanar arcs (VMATc + nc). Acute toxicity was evaluated according to NCI CTCAE criteria V4.03. Results: Median age was 62 years. Localization of tumor was the mobile tongue for 6 patients, floor of mouth for 2, cheek for 1, and gingiva for 1. Six patients had pT2N0 tumors (AJCC 7th edition) and 4 had pT1N0. Mean CTV and PTV volumes were 36.4 and 56.1 cc respectively. Mean PTV coverage by the 36 Gy isodose was 98.2 % for both techniques (p = ns), with comparable conformity indexes (1.1 for VMATc vs 1.07 for VMATc + nc; p = 0.23). VMATc + nc had a significantly better gradient index (3.45 vs 2.97; p = 0.01), resulting in a significantly better sparing of most organs at risk. For example, mean Dmean to the oral cavity, lips, and homolateral parotid were respectively of 16.8 Gy, 11.1 Gy, and 10.4 Gy for VMATc vs 14.8 Gy (p = 0.005), 8.1 Gy (p = 0.001), 6.5 Gy (p = 0.04) for VMATc + nc. No grade ≥ 4 or higher acute toxicity was reported. The most common acute toxicity was grade ≥ 2 mucositis. Conclusion: VMATc + nc had better dosimetric outcomes than VMATc and has become the standard technique for patients treated in the STEREO POSTOP GORTEC 2017-03 trial (NCT03401840) in our institution. Acute toxicity appears acceptable.

Outcomes among oropharyngeal and oral cavity cancer patients treated with postoperative volumetric modulated arctherapy.

Background: Presently, there are few published reports on postoperative radiation therapy for oropharyngeal and oral cavity cancers treated with IMRT/VMAT technique. This study aimed to assess the oncological outcomes of this population treated with postoperative VMAT in our institution, with a focus on loco-regional patterns of failure. Material and methods: Between 2011 and 2019, 167 patients were included (40% of oropharyngeal cancers, and 60% of oral cavity cancers). The median age was 60 years. There was 64.2% of stage IV cancers. All patients had both T and N surgery. 34% had a R1 margin, 42% had perineural invasion. 72% had a positive neck dissection and 42% extranodal extension (ENE). All patients were treated with VMAT with simultaneous integrated boost with three dose levels: 66Gy in case of R1 margin and/or ENE, 59.4-60Gy on the tumor bed, and 54Gy on the prophylactic areas. Concomittant cisplatin was administrated concomitantly when feasible in case of R1 and/or ENE. Results: The 1- and 2-year loco-regional control rates were 88.6% and 85.6% respectively. Higher tumor stage (T3/T4), the presence of PNI, and time from surgery >45 days were significant predictive factors of worse loco-regional control in multivariate analysis (p=0.02, p=0.04, and p=0.02). There were 17 local recurrences: 11 (64%) were considered as infield, 4 (24%) as marginal, and 2 (12%) as outfield. There were 9 regional recurrences only, 8 (89%) were considered as infield, and 1 (11%) as outfield. The 1- and 2-year disease-free survival (DFS) rates were 78.9% and 71.8% respectively. The 1- and 2-year overall survival (OS) rates were 88.6% and 80% respectively. Higher tumor stage (T3/T4) and the presence of ENE were the two prognostic factors significantly associated with worse DFS and OS in multivariate analysis. Conclusion: Our outcomes for postoperative VMAT for oral cavity and oropharyngeal cancers are encouraging, with high rates of loco-regional control. However, the management of ENE still seems challenging.

Practical and technical key challenges in head and neck adaptive radiotherapy: The GORTEC point of view.

Anatomical variations occur during head and neck (H&N) radiotherapy (RT) treatment. These variations may result in underdosage to the target volume or overdosage to the organ at risk. Replanning during the treatment course can be triggered to overcome this issue. Due to technological, methodological and clinical evolutions, tools for adaptive RT (ART) are becoming increasingly sophisticated. The aim of this paper is to give an overview of the key steps of an H&N ART workflow and tools from the point of view of a group of French-speaking medical physicists and physicians (from GORTEC). Focuses are made on image registration, segmentation, estimation of the delivered dose of the day, workflow and quality assurance for an implementation of H&N offline and online ART. Practical recommendations are given to assist physicians and medical physicists in a clinical workflow.

DTI Abnormalities Related to Glioblastoma: A Prospective Comparative Study with Metastasis and Healthy Subjects.

(1) Background: Glioblastoma multiforme (GBM) shows complex mechanisms of spreading of the tumor cells, up to remote areas, and little is still known of these mechanisms, thus we focused on MRI abnormalities observable in the tumor and the brain adjacent to the lesion, up to the contralateral hemisphere, with a special interest on tensor diffusion imaging informing on white matter architecture; (2) Material and Methods: volumes, macroscopic volume (MV), brain-adjacent-tumor (BAT) volume and abnormal color-coded DTI volume (aCCV), and region-of-interest samples (probe volumes, ipsi, and contra lateral to the lesion), with their MRI characteristics, apparent diffusion coefficient (ADC), fractional anisotropy (FA) values, and number of fibers (DTI fiber tracking) were analyzed in patients suffering GBM (n = 15) and metastasis (n = 9), and healthy subjects (n = 15), using ad hoc statistical methods (type I error = 5%) (3) Results: GBM volumes were larger than metastasis volumes, aCCV being larger in GBM and BAT ADC was higher in metastasis, ADC decreased centripetally in metastasis, FA increased centripetally either in GBM or metastasis, MV and BAT FA values were higher in GBM, ipsi FA values of GBM ROIs were higher than those of metastasis, and the GBM ipsi number of fibers was higher than the GBM contra number of fibers; (4) Conclusions: The MV, BAT and especially the aCCV, as well as their related water diffusion characteristics, could be useful biomarkers in oncology and functional oncology.