Extended follow-up of a phase 2 trial of xevinapant plus chemoradiotherapy in high-risk locally advanced squamous cell carcinoma of the head and neck: a randomised clinical trial

INTRODUCTION

We report long-term efficacy and overall survival (OS) results from a randomised, double-blind, phase 2 study (NCT02022098) investigating xevinapant plus standard-of-care chemoradiotherapy (CRT) vs. placebo plus CRT in 96 patients with unresected locally advanced squamous cell carcinoma of the head and neck (LA SCCHN).

METHODS

Patients were randomised 1:1 to xevinapant 200 mg/day (days 1-14 of a 21-day cycle for 3 cycles), or matched placebo, plus CRT (cisplatin 100 mg/m² every 3 weeks for 3 cycles plus conventional fractionated high-dose intensity-modulated radiotherapy [70 Gy/35 F, 2 Gy/F, 5 days/week for 7 weeks]). Locoregional control, progression-free survival, and duration of response after 3 years, long-term safety, and 5-year OS were assessed.

RESULTS

The risk of locoregional failure was reduced by 54% for xevinapant plus CRT vs. placebo plus CRT but did not reach statistical significance (adjusted hazard ratio [HR] 0.46; 95% CI, 0.19-1.13; P = .0893). The risk of death or disease progression was reduced by 67% for xevinapant plus CRT (adjusted HR 0.33; 95% CI, 0.17-0.67; P = .0019). The risk of death was approximately halved in the xevinapant arm compared with placebo (adjusted HR 0.47; 95% CI, 0.27-0.84; P = .0101). OS was prolonged with xevinapant plus CRT vs. placebo plus CRT; median OS not reached (95% CI, 40.3-not evaluable) vs. 36.1 months (95% CI, 21.8-46.7). Incidence of late-onset grade ≥3 toxicities was similar across arms.

CONCLUSIONS

In this randomised phase 2 study of 96 patients, xevinapant plus CRT demonstrated superior efficacy benefits, including markedly improved 5-year survival in patients with unresected LA SCCHN.

Pembrolizumab versus cetuximab concurrent with radiotherapy in patients with locally advanced squamous cell carcinoma of head and neck unfit for cisplatin (GORTEC 2015-01 PembroRad): a multicenter, randomized, phase II trial

BACKGROUND

To evaluate potential synergistic effect of pembrolizumab with radiotherapy (RT) compared with a standard-of-care (SOC) cetuximab-RT in patients with locally advanced-squamous cell carcinoma of head and neck (LA-SCCHN).

PATIENTS AND METHODS

Patients with nonoperated stage III-IV SCC of oral cavity, oropharynx, hypopharynx, and larynx and unfit for receiving high-dose cisplatin were enrolled. Patients received once-daily RT up to 69.96 Gy in 33 fractions with weekly cetuximab (cetuximab-RT arm) or 200 mg Q3W pembrolizumab during RT (pembrolizumab-RT arm). The primary endpoint was locoregional control (LRC) rate 15 months after RT. To detect a difference between arms of 60%-80% in 15-month LRC, inclusion of 66 patients per arm was required to achieve a power of at least 0.85 at two-sided significance level of 0.20.

RESULTS

Between May 2016 and October 2017, 133 patients were randomized to cetuximab-RT (n = 66) and pembrolizumab-RT (n = 67). Two patients (one in each arm) were not included in the analysis (a consent withdrawal and a progression before treatment start). The median age was 65 years (interquartile range 60-70 years), 92% were smokers, 60% were oropharynx (46% of oropharynx with p16+) and 75% were stage IV. Median follow-up was 25 months in both arms. The 15-month LRC rate was 59% with cetuximab-RT and 60% with pembrolizumab-RT ]odds ratio 1.05, 95% confidence interval (CI) 0.43-2.59; P = 0.91]. There was no significant difference between arms for progression-free survival (hazard ratio 0.85, 95% CI 0.55-1.32; P = 0.47) and for overall survival (hazard ratio 0.83, 95% CI 0.49-1.40; P = 0.49). Toxicity was lower in the pembrolizumab-RT arm than in the cetuximab-RT arm: 74% versus 92% patients with at least one grade ≥3 adverse events (P = 0.006), mainly due to mucositis, radiodermatitis, and rash.

CONCLUSION

Compared with the SOC cetuximab-RT, pembrolizumab concomitant with RT did not improve the tumor control and survival but appeared less toxic in unfit patients with LA-SCCHN.

Radiotherapy for endometrial cancer

The first intent upfront treatment of endometrial cancer is surgery. External radiotherapy and brachytherapy; however, are important tools in adjuvant setting, according to histopathological risk factors for locoregional recurrence or in the event of an inoperable tumor. We present the update of the recommendations of the French society of oncological radiotherapy on the indications and technical methods of performing radiotherapy and brachytherapy for endometrial cancer.

Radiotherapy of cervical cancer

External beam radiotherapy and brachytherapy are major treatments in the management of cervical cancer. For early-stage tumours with local risk factors, brachytherapy is a preoperative option. Postoperative radiotherapy is indicated according to histopathological criteria. For advanced local tumours, chemoradiation is the standard treatment, followed by brachytherapy boost, which is not optional. We present the update of the recommendations of the French Society of Oncological Radiotherapy on the indications and techniques for external beam radiotherapy and brachytherapy for cervical cancer.

Role of radiotherapy in the management of vulvar cancer: Recommendations of the French society for radiation oncology

Primary vulvar carcinomas are rare gynaecological cancers, for which surgery is the mainstay of treatment. There is however a major place for external beam radiotherapy in the situation of inoperable locally advanced tumours and/or as adjuvant therapy, when there are risk factors for locoregional relapse. We present the recommendations of the French society for radiation oncology on the indications and techniques for radiotherapy in the treatment of primary vulvar cancer.

Image-guided radiotherapy

We present the updated recommendations of the French society for oncological radiotherapy on image-guided radiotherapy (IGRT). The objective of the IGRT is to take into account the anatomical variations of the target volume occurring between or during the irradiation fractions, such as displacements and/or deformations, so that the delivered dose corresponds to the planned dose. This article presents the different IGRT devices, their use and quality control, and quantify the possible additional dose generated by each of them. The practical implementation of IGRT in various tumour locations is summarised, from the different "RecoRad™" guideline articles. Adaptive radiotherapy is then detailed, due to its complexity and its probable development in the next years. The place of radiation technologist in the practice of IGRT is then specified. Finally, a brief update is proposed on the delicate question of the additional dose linked to the in-room imaging, which must be estimated and documented at a minimum, as long as it is difficult to integrate it into the calculation of the dose distribution.

Deep learning methods to generate synthetic CT from MRI in radiotherapy: A literature review

PURPOSE

In radiotherapy, MRI is used for target volume and organs-at-risk delineation for its superior soft-tissue contrast as compared to CT imaging. However, MRI does not provide the electron density of tissue necessary for dose calculation. Several methods of synthetic-CT (sCT) generation from MRI data have been developed for radiotherapy dose calculation. This work reviewed deep learning (DL) sCT generation methods and their associated image and dose evaluation, in the context of MRI-based dose calculation.

METHODS

We searched the PubMed and ScienceDirect electronic databases from January 2010 to March 2021. For each paper, several items were screened and compiled in figures and tables.

RESULTS

This review included 57 studies. The DL methods were either generator-only based (45% of the reviewed studies), or generative adversarial network (GAN) architecture and its variants (55% of the reviewed studies). The brain and pelvis were the most commonly investigated anatomical localizations (39% and 28% of the reviewed studies, respectively), and more rarely, the head-and-neck (H&N) (15%), abdomen (10%), liver (5%) or breast (3%). All the studies performed an image evaluation of sCTs with a diversity of metrics, with only 36 studies performing dosimetric evaluations of sCT.

CONCLUSIONS

The median mean absolute errors were around 76 HU for the brain and H&N sCTs and 40 HU for the pelvis sCTs. For the brain, the mean dose difference between the sCT and the reference CT was <2%. For the H&N and pelvis, the mean dose difference was below 1% in most of the studies. Recent GAN architectures have advantages compared to generator-only, but no superiority was found in term of image or dose sCT uncertainties. Key challenges of DL-based sCT generation methods from MRI in radiotherapy is the management of movement for abdominal and thoracic localizations, the standardization of sCT evaluation, and the investigation of multicenter impacts.

Cetuximab, docetaxel, and cisplatin versus platinum, fluorouracil, and cetuximab as first-line treatment in patients with recurrent or metastatic head and neck squamous-cell carcinoma (GORTEC 2014-01 TPExtreme): a multicentre, open-label, randomised, phase 2 trial

BACKGROUND

Results from a phase 2 trial of the TPEx chemotherapy regimen (docetaxel-platinum-cetuximab) showed promising results, with a median overall survival of 14·0 months in first-line recurrent or metastatic head and neck squamous-cell carcinoma (HNSCC). We therefore aimed to compare the efficacy and safety of the TPEx regimen with the standard of care EXTREME regimen (platinum-fluorouracil-cetuximab) in this setting.

METHODS

This was a multicentre, open-label, randomised, phase 2 trial, done in 68 centres (cancer centres, university and general hospitals, and private clinics) in France, Spain, and Germany. Eligible patients were aged 18-70 years with histologically confirmed recurrent or metastatic HNSCC unsuitable for curative treatment; had at least one measurable lesion according to Response Evaluation Criteria in Solid Tumors version 1.1; and had an Eastern Cooperative Oncology Group (ECOG) performance status of 1 or less. Participants were randomly assigned (1:1) using the TenAlea website by investigators or delegated clinical research associates to the TPEx regimen or the EXTREME regimen, with minimisation by ECOG performance status, type of disease evolution, previous cetuximab treatment, and country. The TPEx regimen consisted of docetaxel 75 mg/m² and cisplatin 75 mg/m², both intravenously on day 1, and cetuximab on days 1, 8, and 15 (intravenously 400 mg/m² on day 1 of cycle 1 and 250 mg/m² weekly subsequently). Four cycles were repeated every 21 days with systematic granulocyte colony-stimulating factor (G-CSF) support at each cycle. In case of disease control after four cycles, intravenous cetuximab 500 mg/m² was continued every 2 weeks as maintenance therapy until progression or unacceptable toxicity. The EXTREME regimen consisted of fluorouracil 4000 mg/m² on day 1-4, cisplatin 100 mg/m² on day 1, and cetuximab on days 1, 8, and 15 (400 mg/m² on day 1 of cycle 1 and 250 mg/m² weekly subsequently) all delivered intravenously. Six cycles were delivered every 21 days followed by weekly 250 mg/m² cetuximab as maintenance therapy in case of disease control. G-CSF support was not mandatory per the protocol in the EXTREME regimen. The primary endpoint was overall survival in the intention-to-treat population; safety was analysed in all patients who received at least one dose of chemotherapy or cetuximab. Enrolment is closed and this is the final analysis. This study is registered at ClinicalTrials.gov, NCT02268695.

FINDINGS

Between Oct 10, 2014, and Nov 29, 2017, 541 patients were enrolled and randomly assigned to the two treatment regimens (271 to TPEx, 270 to EXTREME). Two patients in the TPEx group had major deviations in consent forms and were not included in the final analysis. Median follow-up was 34·4 months (IQR 26·6-44·8) in the TPEx group and 30·2 months (25·5-45·3) in the EXTREME group. At data cutoff, 209 patients had died in the TPEx group and 218 had died in the EXTREME group. Overall survival did not differ significantly between the groups (median 14·5 months [95% CI 12·5-15·7] in the TPEx group and 13·4 months [12·2-15·4] in the EXTREME group; hazard ratio 0·89 [95% CI 0·74-1·08]; p=0·23). 214 (81%) of 263 patients in the TPEx group versus 246 (93%) of 265 patients in the EXTREME group had grade 3 or worse adverse events during chemotherapy (p<0·0001). In the TPEx group, 118 (45%) of 263 patients had at least one serious adverse event versus 143 (54%) of 265 patients in the EXTREME group. 16 patients in the TPEx group and 21 in the EXTREME group died in association with adverse events, including seven patients in each group who had fatal infections (including febrile neutropenia). Eight deaths in the TPEx group and 11 deaths in the EXTREME group were assessed as treatment related, most frequently sepsis or septic shock (four in each treatment group).

INTERPRETATION

Although the trial did not meet its primary endpoint, with no significant improvement in overall survival with TPEx versus EXTREME, the TPEx regimen had a favourable safety profile. The TPEx regimen could provide an alternative to standard of care with the EXTREME regimen in the first-line treatment of patients with recurrent or metastatic HNSCC, especially for those who might not be good candidates for up-front pembrolizumab treatment.

FUNDING

Merck Santé and Chugai Pharma.

Durvalumab with or without tremelimumab in patients with recurrent or metastatic head and neck squamous cell carcinoma: EAGLE, a randomized, open-label phase III study

BACKGROUND

Targeting the programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) axis has demonstrated clinical benefit in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). Combining immunotherapies targeting PD-L1 and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) has shown evidence of additive activity in several tumor types. This phase III study evaluated the efficacy of durvalumab (an anti-PD-L1 monoclonal antibody) or durvalumab plus tremelimumab (an anti-CTLA-4 monoclonal antibody) versus standard of care (SoC) in R/M HNSCC patients.

PATIENTS AND METHODS

Patients were randomly assigned to receive 1 : 1 : 1 durvalumab (10 mg/kg every 2 weeks [q2w]), durvalumab plus tremelimumab (durvalumab 20 mg/kg q4w plus tremelimumab 1 mg/kg q4w × 4, then durvalumab 10 mg/kg q2w), or SoC (cetuximab, a taxane, methotrexate, or a fluoropyrimidine). The primary end points were overall survival (OS) for durvalumab versus SoC, and OS for durvalumab plus tremelimumab versus SoC. Secondary end points included progression-free survival (PFS), objective response rate, and duration of response.

RESULTS

Patients were randomly assigned to receive durvalumab (n = 240), durvalumab plus tremelimumab (n = 247), or SoC (n = 249). No statistically significant improvements in OS were observed for durvalumab versus SoC [hazard ratio (HR): 0.88; 95% confidence interval (CI): 0.72-1.08; P = 0.20] or durvalumab plus tremelimumab versus SoC (HR: 1.04; 95% CI: 0.85-1.26; P = 0.76). The 12-month survival rates (95% CI) were 37.0% (30.9-43.1), 30.4% (24.7-36.3), and 30.5% (24.7-36.4) for durvalumab, durvalumab plus tremelimumab, and SoC, respectively. Treatment-related adverse events (trAEs) were consistent with previous reports. The most common trAEs (any grade) were hypothyroidism for durvalumab and durvalumab plus tremelimumab (11.4% and 12.2%, respectively), and anemia (17.5%) for SoC. Grade ≥3 trAE rates were 10.1%, 16.3%, and 24.2% for durvalumab, durvalumab plus tremelimumab, and SoC, respectively.

CONCLUSION

There were no statistically significant differences in OS for durvalumab or durvalumab plus tremelimumab versus SoC. However, higher survival rates at 12 to 24 months and response rates demonstrate clinical activity for durvalumab.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02369874.

Implementation of an optimization method for parotid gland sparing during inverse planning for head and neck cancer radiotherapy

PURPOSE

To guide parotid gland (PG) sparing at the dose planning step, a specific model based on overlap between PTV and organ at risk (Moore et al.) was developed and evaluated for VMAT in head-and-neck (H&N) cancer radiotherapy.

MATERIALS AND METHODS

One hundred and sixty patients treated for locally advanced H&N cancer were included. A model optimization was first performed (20 patients) before a model evaluation (110 patients). Thirty cases were planned with and without the model to quantify the PG dose sparing. The inter-operator variability was evaluated on one case, planned by 12 operators with and without the model. The endpoints were PG mean dose (D_mean), PTV homogeneity and number of monitor units (MU).

RESULTS

The PG D_mean predicted by the model was reached in 89% of cases. Using the model significantly reduced the PG D_mean: -6.1±4.3Gy. Plans with the model showed lower PTV dose homogeneity and more MUs (+10.5% on average). For the inter-operator variability, PG dose volume histograms without the optimized model were significantly different compared to those with the model; the D_mean standard deviation for the ipsilateral PG decreased from 2.2Gy to 1.2Gy. For the contralateral PG, this value decreased from 2.9Gy to 0.8Gy.

CONCLUSION

During the H&N inverse planning, the optimized model guides to the lowest PG achievable mean dose, allowing a significant PG mean dose reduction of -6.1Gy. Integrating this method at the treatment-planning step significantly reduced the inter-patient and inter-operator variabilities.

Angular resolution expected from iCHORD orientation maps through a revisited ion channeling model

Crystalline orientation maps are obtained in a Focused Ion Beam (FIB) microscope using the ion CHanneling ORientation Determination (iCHORD) method, which relies on the channeling phenomenon observed in ion-induced secondary electron images. The current paper focuses on the angular resolution that can be expected from such orientation maps, obtained using a revisited ion channeling model. A specific procedure was developed to evaluate the angular resolution, based on the distribution of orientation errors when evaluating controlled sample disorientation. The main advantage is that no external reference is required. An angular resolution of 1° is obtained on a nickel based sample using standard acquisition conditions. This value fulfills most of the needs in terms of microstructural characterization usually carried out by Electron Back Scattered Diffraction.

[Siriade 2.0: An e-learning platform for radiation oncology contouring]

PURPOSE

In 2008, the French national society of radiation oncology (SFRO) and the association for radiation oncology continued education (AFCOR) created Siriade, an e-learning website dedicated to contouring.

MATERIAL AND METHODS

Between 2015 and 2017, this platform was updated using the latest digital online tools available. Two main sections were needed: a theoretical part and another section of online workshops.

RESULTS

Teaching courses are available as online commented videos, available on demand. The practical section of the website is an online contouring workshop that automatically generates a report quantifying the quality of the user's delineation compared with the experts'.

CONCLUSION

Siriade 2.0 is an innovating digital tool for radiation oncology initial and continuous education.

A density assignment method for dose monitoring in head-and-neck radiotherapy

BACKGROUND AND PURPOSE

During head-and-neck (H&N) radiotherapy, the parotid glands (PGs) may be overdosed; thus, a tool is required to monitor the delivered dose. This study aimed to assess the dose accuracy of a patient-specific density assignment method (DAM) for dose calculation to monitor the dose to PGs during treatment.

PATIENTS AND METHODS

Forty patients with H&N cancer received an intensity modulated radiation therapy (IMRT), among whom 15 had weekly CTs. Dose distributions were calculated either on the CTs (CT_ref), on one-class CTs (1C-CT, water), or on three-class CTs (3C-CT, water-air-bone). The inter- and intra-patient DAM uncertainties were evaluated by the difference between doses calculated on CT_ref and 1C-CTs or 3C-CTs. PG mean dose (D_mean) and spinal cord maximum dose (D_2%) were considered. The cumulated dose to the PGs was estimated by the mean D_mean of the weekly CTs.

RESULTS

The mean (maximum) inter-patient DAM dose uncertainties for the PGs (in cGy) were 23 (75) using 1C-CTs and 12 (50) using 3C-CTs (p ≤ 0.001). For the spinal cord, these uncertainties were 118 (245) and 15 (67; p ≤ 0.001). The mean (maximum) DAM dose uncertainty between cumulated doses calculated on CTs and 3C-CTs was 7 cGy (45 cGy) for the PGs. Considering the difference between the planned and cumulated doses, 53% of the ipsilateral and 80% of the contralateral PGs were overdosed by +3.6 Gy (up to 8.2 Gy) and +1.9 Gy (up to 5.2 Gy), respectively.

CONCLUSION

The uncertainty of the three-class DAM appears to be clinically non-significant (<0.5 Gy) compared with the PG overdose (up to 8.2 Gy). This DAM could therefore be used to monitor PG doses and trigger replanning.

Adaptive radiotherapy for head and neck cancer

INTRODUCTION

Large anatomical variations can be observed during the treatment course intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC), leading to potential dose variations. Adaptive radiotherapy (ART) uses one or several replanning sessions to correct these variations and thus optimize the delivered dose distribution to the daily anatomy of the patient. This review, which is focused on ART in the HNC, aims to identify the various strategies of ART and to estimate the dosimetric and clinical benefits of these strategies.

MATERIAL AND METHODS

We performed an electronic search of articles published in PubMed/MEDLINE and Science Direct from January 2005 to December 2016. Among a total of 134 articles assessed for eligibility, 29 articles were ultimately retained for the review. Eighteen studies evaluated dosimetric variations without ART, and 11 studies reported the benefits of ART.

RESULTS

Eight in silico studies tested a number of replanning sessions, ranging from 1 to 6, aiming primarily to reduce the dose to the parotid glands. The optimal timing for replanning appears to be early during the first two weeks of treatment. Compared to standard IMRT, ART decreases the mean dose to the parotid gland from 0.6 to 6 Gy and the maximum dose to the spinal cord from 0.1 to 4 Gy while improving target coverage and homogeneity in most studies. Only five studies reported the clinical results of ART, and three of those studies included a non-randomized comparison with standard IMRT. These studies suggest a benefit of ART in regard to decreasing xerostomia, increasing quality of life, and increasing local control. Patients with the largest early anatomical and dose variations are the best candidates for ART.

CONCLUSION

ART may decrease toxicity and improve local control for locally advanced HNC. However, randomized trials are necessary to demonstrate the benefit of ART before using the technique in routine practice.

[Organization and risk management in stereotaxic body radiotherapy at the treatment station]

The development of stereotaxic body radiotherapy in the last decade has forced the radiotherapy departments to redouble their efforts in the fields of quality and risk management. For this purpose, increasingly complex and rigorous controls of high performance machines as well as a solid team training must be put in place. Extreme hypofractionation requires both increased vigilance at the treatment desk and well-defined and known procedures. The in place organizations contribute to the control of the risks related to the stereotaxic body radiotherapy machines. The medical presence at the beginning of the treatment fractions has been specified as mandatory in a regulatory way since January 2017. This not only ensures security, but also transmits information to the radiation therapy technicians. At the Eugène-Marquis center, the skills of the technicians for stereotaxic body radiotherapy on two dedicated machines (Cyberknife^® and Versa HD^® Novalis^® type) have been upgraded. An accreditation is formalized after a training period and re-evaluated annually. The communication inside and outside the radiotherapy field plays also an important role in maintaining a high level of exchange and sharing of essential information. The means implemented at the Eugène-Marquis center increase the risk control of SBRT, by paying attention to the management of skills at the treatment station.