[Proposal for the delineation of postoperative primary clinical target volumes in maxillary sinus and nasal cavity cancers]

In this article, we propose a consensus delineation of postoperative clinical target volumes for the primary tumour in maxillary sinus and nasal cavity cancers. These guidelines are developed based on radioanatomy and the natural history of those cancers. They require the fusion of the planning CT with preoperative imaging for accurate positioning of the initial GTV and the combined use of the geometric and anatomical concepts for the delineation of clinical target volume for the primary tumour. This article does not discuss the indications of external radiotherapy (nor concurrent systemic treatment) but focuses on target volumes when there is an indication for radiotherapy.

Novel Radioenhancer NBTXR3 Activated by Radiotherapy in Cisplatin-Ineligible Locally Advanced HNSCC Patients: Final Results of a Phase I Trial

PURPOSE/OBJECTIVE(S)

New approaches are needed for frail or elderly patients with locally advanced head and neck squamous cell carcinoma (LA HNSCC) who are unfit to receive cisplatin with concurrent radiotherapy (RT). NBTXR3 is a first-in-class radioenhancer, composed of functionalized hafnium oxide nanoparticles, administered by a single intratumoral (IT) injection and activated by RT. NBTXR3 locally amplifies the anti-tumoral response of RT without adding toxicity to surrounding healthy tissue as shown in a randomized trial in soft tissue sarcoma. This two-part study: dose-escalation followed by the dose-expansion part reported here, evaluated the safety and preliminary efficacy for NBTXR3 activated by RT in elderly or frail patients ineligible to cisplatin.

MATERIALS/METHODS

This trial enrolled patients who had previously untreated AJCC 8th Stage III-IVA or T3, T4 SCC of the oral cavity or oropharynx (OPC) ineligible to cisplatin. Eligible patients received a single IT injection of NBTXR3 at the recommended dose (22% of the baseline tumor volume) followed by RT (IMRT 70 Gy in 35 fractions). The primary objectives of the dose expansion part were to test the recommended dose, to confirm its safety, and obtain preliminary evidence of efficacy. The secondary objectives included the evaluation of progression-free survival (PFS) and overall survival (OS).

RESULTS

Fifty-sixpatients in the dose expansion part were treated from April 2019-January 2022; 44 patients were evaluable for objective tumor response. In the all-treated population, median age was 71.9 years. 64.3% had age-adjusted Charlson Comorbidity Index scores ≥4, 55.4% had OPC (45.2% HPV+) and 80% had T3-4. Median injected volume of NBTXR3 was 13.6 [0.5-57.1] mL. Grade ≥ 3 adverse events reported as potentially related to NBTXR3 or to injection procedure were 1.2% and 0.4% of all AEs reported, respectively. In the evaluable population, the best objective response rate of the NBTXR3 injected lesion was 81.8% with a complete response rate of 63.6%. The best overall response rate (injected and non-injected lesions) was 79.5%. Final analyses on PFS and OS with long-term follow-up will be presented.

CONCLUSION

NBTXR3 IT injection followed by activation with RT was confirmed to be feasible and well tolerated in elderly or frail patients with LA HNSSC and significant comorbidities. The high rate of best overall response suggests that NBTXR3+RT is effective in this elderly population ineligible to cisplatin with a high unmet medical need. These results support our ongoing phase III study comparing NBTXR3/RT ± cetuximab vs. RT ± cetuximab in platinum-based chemotherapy ineligible elderly patients with LA-HNSCC: NANORAY 312 (NCIT04892173).

Efficacy of Protontherapy in Atypical Meningiomas

PURPOSE/OBJECTIVE(S)

To assess the efficacy and safety of complementary radiotherapy (RT) [by proton beams alone (PT) or in combination with photon beams (Ph)] to surgery in the local treatment of atypical meningiomas.

MATERIALS/METHODS

One hundred one consecutive patients with atypical (WHO grade II) meningiomas were treated with PT +/- Ph at our institution between Nov 1996 to Sep 2022. The total median dose was 59.4 Gy RBE (range 59.4- 68.4) with Proton component alone (n = 76) or PT + Ph (n = 25). The median age at RT was 57.2 years old (range 22.0-79.6). Localization was supratentorial in 62 patients (61.4%), skull base in 29 patients (28.7%), and infratentorial in 10 patients (9.9%). Gross tumor resection was reported in 20 cases (19.8%) and subtotal in 81 (80.2%), 34 patients underwent multiples (2-4) surgeries before RT. Overall survival (OS), meningioma related survival (MRS), Progression Free Survival (PFS), Time to Local progression (TLP), and 3, 5 and 10-year survival rates were evaluated using Kaplan-Meier method. All post-PT clinical toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE v 5.0).

RESULTS

During follow-up after PT (median 47.8 months), local progression was reported in 26 patients (25.7%) and 24 patients died (including 13 meningioma-related deaths). Median TLP was 34.3 months (IC 95% 1.9-128.1), OS was 163 months (IC95% 93.9-232.2), MRS was 34.3 (IC 95% 1.9-128.1) and PFS was 41.4 (IC 95% 1.5-217.8). Actuarial 3, 5 and 9-year OS was 83%, 78% and 66%, while MRS was 89%, 83% and 71% respectively. Patients treated with PT alone presented better OS with 9 deaths (6 meningioma-related deaths) and median of 163.0 months [IC95% (93.9-232.2)], 3y-95%, 5y-93%, 10y-65%, respectively. However, the Patients treated with PT+Ph presented 15 deaths (7 meningioma-related deaths) and median of 51.9 months [IC 95% (7.0-96.8); 2y-75%, 5y-50%, 10y-50%) (p = 0.018). Median TLR was 36.4 months (26.6-46.2) after PT alone and 11.9 months (10.3-13.5) after PT+Ph. However, well-controlled radionecrosis ≤ Grade2 was more frequent after PT alone 20 cases vs 3 cases after PT+Ph. Long-term symptoms was observed during the last visit in 45 patients (44.6%) treated with PT vs. 8 (38.1%) treated with PT+Ph.

CONCLUSION

PT alone or PT+Ph were effective and well-tolerated treatment in WHO grade II meningioma and PT alone appeared to be better for the local control and survival.

[Radiotherapy of rare head and neck tumors]

Management of head and neck tumors is complex because of multiple anatomical locations and histologies possibilities. Rare tumors must be managed in a specialized center and be registered in the French network of expertise on ENT Cancers (Refcor). Despite heterogeneous levels of evidence, radiotherapy plays an essential role in their treatment. Radiation therapy is generally indicated in the adjuvant setting, or in case of non-operability. Dose and target volumes depend on histology, location and extensions of the tumor, and the quality of the excision if applicable. We present here a review of the literature and available guidelines for the management by radiotherapy of rare upper aerodigestive tract tumors.

Role of proton therapy in reirradiation and in the treatment of sarcomas

Reirradiation and irradiation of sarcoma is often difficult due to the frequent need for a high dose of radiation in order to increase tumor control. This can result in a greater risk of toxicity which can be mitigated with the use of proton therapy. The present review aims to summarize the role of proton therapy in these 2 clinical contexts.

Head and neck proton therapy in France: A missed opportunity or a challenge in front of us?

Following major advances of the best of photon-techniques such as intensity-modulated radiotherapy (IMRT), stereotactic body radiotherapy (SBRT) and, to arrive soon, magnetic resonance (MR)-linac radiotherapy, there are still substantial opportunities in the treatment of head and neck cancers to further reduce the toxicity burden. Proton therapy represents another attractive option in this high-quality and highly competitive precision radiotherapy landscape. Proton therapy holds promises to reduce toxicities and to escalate the dose in radioresistant cases or cases where dose distribution is not satisfactory with photons. However, the selection of patients for proton therapy needs to be done using evidence-based medicine to build arguments in favor of personalized precision radiation therapy. Referral to proton therapy versus IMRT or SBRT should be registered (ProtonShare® platform) and envisioned in a formalized clinical research perspective through randomized trials. The use of an enrichment process using a model-based approach should be done to only randomize patients doomed to benefit from proton. To tackle such great opportunities, the French proton therapy challenge is to collaborate at the national and international levels, and to demonstrate that the extra-costs of treatment are worth clinically and economically in the short, mid, and long-term. In parallel to the clinical developments, there are still preclinical issues to be tackled (e.g., proton FLASH, mini-beams, combination with immunotherapy), for which the French Radiotransnet network offers a unique platform. The current article provides a personal view of the challenges and opportunities with a focus on clinical research and randomized trial requirements as well as the needs for strong collaborations at the national and international levels for PT in squamous cell carcinomas of the head and neck to date.

Prognostic value of tumor mutational burden in patients with oral cavity squamous cell carcinoma treated with upfront surgery

Background

Oral cavity is the most prevalent site of head and neck squamous cell carcinomas (HNSCCs). Most often diagnosed at a locally advanced stage, treatment is multimodal with surgery as the cornerstone. The aim of this study was to explore the molecular landscape of a homogenous cohort of oral cavity squamous cell carcinomas (OCSCCs), and to assess the prognostic value of tumor mutational burden (TMB), along with classical molecular and clinical parameters.

Patients and methods

One hundred and fifty-one consecutive patients with OCSCC treated with upfront surgery at the Institut Curie were analyzed. Sequencing of tumor DNA from frozen specimens was carried out using an in-house targeted next-generation sequencing panel (571 genes). The impact of molecular alterations and TMB on disease-free survival (DFS) and overall survival (OS) was evaluated in univariate and multivariate analyses.

Results

Pathological tumor stage, extranodal spread, vascular emboli, and perineural invasion were associated with both DFS and OS. TP53 was the most mutated gene (71%). Other frequent molecular alterations included the TERT promoter (50%), CDKN2A (25%), FAT1 (17%), PIK3CA (14%), and NOTCH1 (15%) genes. Transforming growth factor-β pathway alterations (4%) were associated with poor OS (P = 0.01) and DFS (P = 0.02) in univariate and multivariate analyses. High TMB was associated with prolonged OS (P = 0.01 and P = 0.02, in the highest 10% and 20% TMB values, respectively), but not with DFS. Correlation of TMB with OS remained significant in multivariate analysis (P = 0.01 and P = 0.005 in the highest 10% and 20% TMB values, respectively). Pathological tumor stage combined with high TMB was associated with good prognosis.

Conclusion

Our results suggest that a high TMB is associated with a favorable prognosis in patients with OCSCC treated with upfront surgery.

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High TMB is associated with a favorable prognosis in patients with OCSCC treated with upfront surgery

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Pathological tumor stage combined with high TMB is associated with good prognosis

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TP53 was the most mutated gene (71%). Other frequent molecular alterations included the TERT promoter (50%)

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TGFβ pathway alterations were associated with poor outcomes, although it was only observed in 4% of the patients

[Proposal for the delineation of postoperative primary clinical target volumes in ethmoid cancers]

It is proposed to delineate the anatomo-clinical target volumes of primary tumor (CTV-P) in ethmoid cancers treated with post-operative radiotherapy. This concept is based on the use of radioanatomy and the natural history of cancer. It is supported by the repositioning of the planning scanner with preoperative imaging for the replacement of the initial GTV and the creation of margins around it extended to the microscopic risk zones according to the anatomical concept. This article does not discuss the indications of external radiotherapy but specifies the volumes to be delineated if radiotherapy is considered.

Review of clinical applications of radiation-enhancing nanoparticles

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Inorganic nanoparticles activated by radiotherapy (RT) increase dose deposition within cancer cells compared to RT alone.

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Recently, clinical evidence of the radiation-enhancing effects of NP has emerged.

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Two radio-enhancement NP are currently under investigation in clinical trials: hafnium oxide NP and gadolinium-based NP.

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So far, 229 patients have been treated with NP and RT for soft tissue sarcoma, head and neck cancers or liver cancer.

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Intratumoral hafnium oxide nanoparticles were safe and improved efficacy in locally advanced sarcoma.

Purpose

Clinical evidence of the radiation-enhancing effects of nanoparticles has emerged.

Materials and methods

We searched the literature in English and French on PubMed up to October 2019. The search term was “nanoparticle” AND “radiotherapy”, yielding 1270 results.

Results

The two main NP used in clinical trials were hafnium oxide and gadolinium involving a total of 229 patients. Hafnium oxide NP were used in three phase 1/2 trials on sarcoma, head and neck squamous cell carcinoma or liver cancer and one phase 2/3 trial. There are six ongoing phase 1/2 clinical trials to evaluate the combination of gadolinium-based NP and RT for the treatment of brain metastases and cervical cancer.

Conclusion

So far, intratumoral hafnium oxide nanoparticles were safe and improved efficacy in locally advanced sarcoma.

[Proton therapy for head and neck squamous cell carcinomas: From physics to clinic]

Intensity-modulated radiation therapy (IMRT) is presently the recommended technique for the treatment of locally advanced head and neck carcinomas. Proton therapy would allow to reduce the volume of irradiated normal tissue and, thus, to decrease the risk of late dysphagia, xerostomia, dysgeusia and hypothyroidism. An exhaustive research was performed with the search engine PubMed by focusing on the papers about the physical difficulties that slow down use of proton therapy for head and neck carcinomas. Range uncertainties in proton therapy (±3 %) paradoxically limit the use of the steep dose gradient in distality. Calibration uncertainties can be important in the treatment of head and neck cancer in the presence of materials of uncertain stoichiometric composition (such as with metal implants, dental filling, etc.) and complex heterogeneities. Dental management for example may be different with IMRT or proton therapy. Some uncertainties can be somewhat minimized at the time of optimization. Inter- and intrafractional variations and uncertainties in Hounsfield units/stopping power can be integrated in a robust optimization process. Additional changes in patient's anatomy (tumour shrinkage, changes in skin folds in the beam patch, large weight loss or gain) require rescanning. Dosimetric and small clinical studies comparing photon and proton therapy have well shown the interest of proton therapy for head and neck cancers. Intensity-modulated proton therapy is a promising treatment as it can reduce the substantial toxicity burden of patients with head and neck squamous cell carcinoma compared to IMRT. Robust optimization will allow to perform an optimal treatment and to use proton therapy in current clinical practice.

[Technical aspects and indications of extracranial stereotactic radiotherapy]

Extracranial stereotactic radiotherapy has developed considerably in recent years and is now an important part of the therapeutic alternatives to be offered to patients with cancer. It offers opportunities that have progressively led physicians to reconsider the therapeutic strategy, for example in the case of local recurrence in irradiated territory or oligometastatic disease. The literature on the subject is rich but, yet, there is no real consensus on therapeutic indications. This is largely due to the lack of prospective, randomized studies that have evaluated this technique with sufficient recoil. We propose a review of the literature on the technical aspects and indications of extracranial stereotactic radiotherapy.

Comprehensive genomic profiling of head and neck squamous cell carcinoma reveals FGFR1 amplifications and tumour genomic alterations burden as prognostic biomarkers of survival

BACKGROUND

We aimed at identifying deleterious genomic alterations from untreated head and neck squamous cell carcinoma (HNSCC) patients, and assessing their prognostic value.

PATIENTS AND METHODS

We retrieved 122 HNSCC patients who underwent primary surgery. Targeted NGS was used to analyse a panel of 100 genes selected among the most frequently altered genes in HNSCC and potential therapeutic targets. We selected only deleterious (activating or inactivating) single nucleotide variations, and copy number variations for analysis. Univariate and multivariate analyses were performed to assess the prognostic value of altered genes.

RESULTS

A median of 2 (range: 0-10) genomic alterations per sample was observed. Most frequently altered genes involved the cell cycle pathway (TP53 [60%], CCND1 [30%], CDKN2A [25%]), the PI3K/AKT/MTOR pathway (PIK3CA [12%]), tyrosine kinase receptors (EGFR [9%], FGFR1 [5%]) and cell differentiation (FAT1 [7%], NOTCH1 [4%]). TP53 mutations (p = 0.003), CCND1 amplifications (p = 0.04), CDKN2A alterations (p = 0.02) and FGFR1 amplifications (p = 0.003), correlated with shorter overall survival (OS). The number of genomic alterations was significantly higher in the HPV-negative population (p = 0.029) and correlated with a shorter OS (p < 0.0001). Only TP53 mutation and FGFR1 amplification status remained statistically significant in the multivariate analysis.

CONCLUSION

These results suggest that genomic alterations involving the cell cycle (TP53, CCND1, CDKN2A), as well as FGFR1 amplifications and tumour genomic alterations burden are prognostic biomarkers and might be therapeutic targets for patients with HNSCC.

Use of gEUD for predicting ear and pituitary gland damage following proton and photon radiation therapy

OBJECTIVE

To determine the relationship between the dose to the inner ear or pituitary gland and radiation-induced late effects of skull base radiation therapy.

METHODS

140 patients treated between 2000 and 2008 were considered for this study. Hearing loss and endocrine dysfunction were retrospectively reviewed on pre- and post-radiation therapy audiometry or endocrine assessments. Two normal tissue complication probability (NTCP) models were considered (Lyman-Kutcher-Burman and log-logistic) whose parameters were fitted to patient data using receiver operating characteristics and maximum likelihood analysis. The method provided an estimation of the parameters of a generalized equivalent uniform dose (gEUD)-based NTCP after conversion of dose-volume histograms to equivalent doses.

RESULTS

All 140 patients had a minimum follow up of 26 months. 26% and 44% of patients experienced mild hearing loss and endocrine dysfunction, respectively. The fitted values for TD50 and γ50 ranged from 53.6 to 60.7 Gy and from 1.9 to 2.9 for the inner ear and were equal to 60.6 Gy and 4.9 for the pituitary gland, respectively. All models were ranked equal according to Akaike's information criterion.

CONCLUSION

Mean dose and gEUD may be used as predictive factors for late ear and pituitary gland late complications after skull base proton and photon radiation therapy.

ADVANCES IN KNOWLEDGE

In this study, we have reported mean dose effects and dose-response relationship of small organs at risk (partial volumes of the inner ear and pituitary gland), which could be useful to define optimal dose constraints resulting in an improved therapeutic ratio.

[Chordoma]

PURPOSES

To review in the literature, all the epidemiological, clinical, radiological, histological and therapeutic data regarding chordomas as well as various notochordal entities: ecchordosis physaliphora, intradural and intraparenchymatous chordomas, benign notochordal cell tumors, parachordomas and extra-axial chordomas. To identify different types of chordomas, including familial forms, associations with tuberous sclerosis, Ollier's disease and Maffucci's syndrome, forms with metastasis and seeding. To assess the recent data regarding molecular biology and progress in targeted therapy. To compare the different types of radiotherapy, especially protontherapy and their therapeutic effects. To review the largest series of chordomas in their different localizations (skull base, sacrum and mobile spine) from the literature.

MATERIALS

The series of 136 chordomas treated and followed up over 20 years (1972-2012) in the department of neurosurgery at Lariboisière hospital is reviewed. It includes: 58 chordomas of the skull base, 47 of the craniocervical junction, 23 of the cervical spine and 8 from the lombosacral region. Similarly, 31 chordomas in children (less than 18 years of age), observed in the departments of neurosurgery of les Enfants-Malades and Lariboisière hospitals, are presented. They were observed between 1976 and 2010 and were located intracranially (n=22 including 13 with cervical extension), 4 at the craniocervical junction level and 5 in the cervical spine.

METHODS

In the entire Lariboisière series and in the different groups of localization, different parameters were analyzed: the delay of diagnosis, of follow-up, of occurrence of metastasis, recurrence and death, the number of primary patients and patients referred to us after progression or recurrence and the number of deaths, recurrences and metastases. The influence of the quality of resection (total, subtotal and partial) on the prognosis is also presented. Kaplan-Meier actuarial curves of overall survival and disease free survival were performed in the entire series, including the different groups of localization based on the following 4 parameters: age, primary and secondary patients, quality of resection and protontherapy. In the pediatric series, a similar analysis was carried-out but was limited by the small number of patients in the subgroups.

RESULTS

In the Lariboisière series, the mean delay of diagnosis is 10 months and the mean follow-up is 80 months in each group. The delay before recurrence, metastasis and death is always better for the skull base chordomas and worse for those of the craniocervical junction, which have similar results to those of the cervical spine. Similar figures were observed as regards the number of deaths, metastases and recurrences. Quality of resection is the major factor of prognosis with 20.5 % of deaths and 28 % of recurrences after total resection as compared to 52.5 % and 47.5 % after subtotal resection. This is still more obvious in the group of skull base chordomas. Adding protontherapy to a total resection can still improve the results but there is no change after subtotal resection. The actuarial curve of overall survival shows a clear cut in the slope with some chordomas having a fast evolution towards recurrence and death in less than 4 years and others having a long survival of sometimes more than 20 years. Also, age has no influence on the prognosis. In primary patients, disease free survival is better than in secondary patients but not in overall survival. Protontherapy only improves the overall survival in the entire series and in the skull base group. Total resection improves both the overall and disease free survival in each group. Finally, the adjunct of protontherapy after total resection is clearly demonstrated. In the pediatric series, the median follow-up is 5.7 years. Overall survival and disease free survival are respectively 63 % and 54.3 %. Factors of prognosis are the histological type (atypical forms), localization (worse for the cervical spine and better for the clivus) and again it will depend on the quality of resection.

CONCLUSIONS

Many different pathologies derived from the notochord can be observed: some are remnants, some may be precursors of chordomas and some have similar features but are probably not genuine chordomas. To-day, immuno-histological studies should permit to differentiate them from real chordomas. Improving knowledge of molecular biology raises hopes for complementary treatments but to date the quality of surgical resection is still the main factor of prognosis. Complementary protontherapy seems useful, especially in skull base chordomas, which have better overall results than those of the craniocervical junction and of the cervical spine. However, we are still lacking an intrinsic marker of evolution to differentiate the slow growing chordomas with an indolent evolution from aggressive types leading rapidly to recurrence and death on which more aggressive treatments should be applied.

Stereotactic radiotherapy for large solitary brain metastases

PURPOSE

To assess effectiveness and toxicity levels of stereotactic radiation therapy without whole brain radiation therapy in patients with solitary brain metastases larger than 3cm.

PATIENTS AND METHODS

Between June 2007 and March 2009, 12 patients received fractionated stereotactic radiation therapy and 24 patients underwent stereotactic radiosurgery. For the fractionated stereotactic radiation therapy group, 3×7.7Gy were delivered to the planning target volume (PTV); median volume and diameter were 29.4 cm(3) and 4.4cm, respectively. For the stereotactic radiosurgery group, 14Gy were delivered to the PTV; median volume and diameter were 15.6 cm(3) and 3.7cm, respectively.

RESULTS

Median follow-up was 218 days. For the fractionated stereotactic radiation therapy group, local control rates were 100% at 360 days and 64% at 720 days; for the stereotactic radiosurgery group, rates were 58% at 360 days and 48% at 720 days (P=0.06). Median survival time was 504 days for the fractionated stereotactic radiation therapy group and 164 days for the stereotactic radiosurgery group (P=0.049). Two cases of grade 2 toxicity were observed in the fractionated stereotactic radiation therapy group, and 6 cases of grade 1-2 toxicity, in the stereotactic radiosurgery group.

CONCLUSIONS

This study provides data to support that fractionated stereotactic radiation therapy without whole brain radiation therapy with a margin dose of 3 fractions of 7.7Gy for treatment of solitary large brain metastases is efficient and well-tolerated. Because of the significant improvement in overall survival, this schedule should be assessed in a randomized trial.