[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.

An international phase II trial and immune profiling of SBRT and atezolizumab in advanced pretreated colorectal cancer

BACKGROUND

Immuno-radiotherapy may improve outcomes for patients with advanced solid tumors, although optimized combination modalities remain unclear. Here, we report the colorectal (CRC) cohort analysis from the SABR-PDL1 trial that evaluated the PD-L1 inhibitor atezolizumab in combination with stereotactic body radiation therapy (SBRT) in advanced cancer patients.

METHODS

Eligible patients received atezolizumab 1200 mg every 3 weeks until progression or unmanageable toxicity, together with ablative SBRT delivered concurrently with the 2nd cycle (recommended dose of 45 Gy in 3 fractions, adapted upon normal tissue tolerance constraint). SBRT was delivered to at least one tumor site, with at least one additional measurable lesion being kept from the radiation field. The primary efficacy endpoint was one-year progression-free survival (PFS) rate from the start of atezolizumab. Sequential tumor biopsies were collected for deep multi-feature immune profiling.

RESULTS

Sixty pretreated (median of 2 prior lines) advanced CRC patients (38 men [63%]; median age, 59 years [range, 20-81 years]; 77% with liver metastases) were enrolled in five centers (France: n = 4, Spain: n = 1) from 11/2016 to 04/2019. All but one (98%) received atezolizumab and 54/60 (90%) received SBRT. The most frequently irradiated site was lung (n = 30/54; 56.3%). Treatment-related G3 (no G4-5) toxicity was observed in 3 (5%) patients. Median OS and PFS were respectively 8.4 [95%CI:5.9-11.6] and 1.4 months [95%CI:1.2-2.6], including five (9%) patients with PFS > 1 year (median time to progression: 19.2 months, including 2/5 MMR-proficient). Best overall responses consisted of stable disease (n = 38; 64%), partial (n = 3; 5%) and complete response (n = 1; 2%). Immune-centric multiplex IHC and RNAseq showed that SBRT redirected immune cells towards tumor lesions, even in the case of radio-induced lymphopenia. Baseline tumor PD-L1 and IRF1 nuclear expression (both in CD3 + T cells and in CD68 + cells) were higher in responding patients. Upregulation of genes that encode for proteins known to increase T and B cell trafficking to tumors (CCL19, CXCL9), migration (MACF1) and tumor cell killing (GZMB) correlated with responses.

CONCLUSIONS

This study provides new data on the feasibility, efficacy, and immune context of tumors that may help identifying advanced CRC patients most likely to respond to immuno-radiotherapy.

TRIAL REGISTRATION

EudraCT N°: 2015-005464-42; Clinicaltrial.gov number: NCT02992912.

CANTO: Skin Toxicities Evaluation of a Multicenter Large Prospective Cohort of Irradiated Patients for Early-Stage Breast Cancer

PURPOSE/OBJECTIVE(S)

Skin damage is a common toxicity during oncology management. Its assessment and understanding of the factors influencing its occurrence, is a major issue in the management of patients treated for an early breast cancer (BC).

MATERIALS/METHODS

CANTO (NCT01993498) is a prospective, multicentric, clinical cohort study of 11 400 patients with stage I-III BC, treated in 26 French cancer centers. In this study, we will evaluate the 8561 patients during their overall management for a BC. We are focus on specifical skin toxicities: Erythema, fibrosis, telangiectasia and skin color (CTCAE v4.0). These toxicities were assessed at 3-6 (M0), 12 (M12), 36 (M36), 60 (M60) months.

RESULTS

The prevalence of toxicities of interest varied over time, so at M0, 30.4% of patients had erythema while 17.7% of patients had fibrosis. At M12, M36 and M60, the prevalence of erythema decreased from 5.5 % to 2.5 % then to 2 %, respectively, while fibrosis remained stable at about 19 %. The prevalence of telangiectasia increased from 0.8 % to 7 % from M0 to M60. While the modification of skin color was 51.1 % at M0, and 10.6 % at M60. After adjustments, at M0, there was a statistically significant association between the onset of cutaneous erythema and obesity, the presence of axillary dissection, the type of surgery the age of the patient as well as the tumor phenotype RH+/HER2+ [OR: 0.79 [0.67; 0.93]]. Concerning fibrosis, a statistically significant association was found, at M12, with the age of the patient, obesity, tumor grade, Charlson score, type of surgery and mitotic index. Obesity and the age of the patient represent at M12 and M36 a risk significantly associated with the onset of telangiectasia. Concerning the modification of skin color at M12, we find a link between the age of the patient, obesity, tobacco consumption, tumor grade, Charlson score, type of surgery, and alcohol consumption [OR: 0.69 [0.51; 0.91]].

CONCLUSION

In this study we identified several risk factors for acute and late skin toxicity. The knowledge of its predictive factors allows a personalized management of the patient by adapting our treatments and our monitoring according to these different factors.

Economic evaluation and budget-impact of accelerated partial breast irradiation (APBI) versus standard or hypofractionated whole breast irradiation (WBI) in postmenopausal women with early-stage breast cancer. Results from the French SHARE randomized trial

PURPOSE

This economic evaluation reports the incremental cost-utility ratio and national budget impact in France of accelerated partial breast irradiation (APBI) vs standard or hypofractionated whole breast irradiation (WBI) in breast cancer patients at low risk of local recurrence.

MATERIALS AND METHODS

We compared 490 women randomized to the APBI (ten fractions delivered twice daily over one week) with 488 women in the WBI arm (one fraction per day delivered five days per week over three or six weeks). We took the perspective of the French national health insurance with a three-year time horizon. The outcome was quality-adjusted life years (QALYs). The incremental cost-effectiveness ratio was estimated and uncertainty was explored by probabilistic bootstrapping. Transportation and sick leave costs were added in a sensitivity analysis and a national budget impact analysis based on the incidence of breast cancer estimates in France performed.

RESULTS

At three years, the average cost per patient was €2,549 (±1,954) in the APBI arm and €4,468 (±1,586) in the WBI arm (p-value < 0.001), radiotherapy was the main driver of the difference between the two arms. No significant difference was found in QALYs. For an average of 60,000 new cases of breast cancer diagnosed annually in France, 28,000 would be eligible for treatment with APBI. A 100% uptake of APBI would result in a yearly30 million€ cost saving.

CONCLUSION

APBI for the treatment of postmenopausal women with early-stage breast cancer is cost saving, with no difference in outcome measured by QALYs.

[Breast cancer radiation therapy: Current questions in 2023]

Radiation therapy is a corner stone of breast cancer treatment as it has been shown postoperatively that it improves local control and overall survival. In recent years, multidisciplinary therapeutic strategies have evolved considerably for early-stage breast cancer, both surgically and in terms of systemic treatments or radiation therapy. Each of these developments affects other treatment components and open up new questions allowing even more personalized treatments. Essentially normofractionated a few years ago, breast radiation therapy is today very largely moderately or even ultra hypofractionated. De-escalation of the surgery of the axilla has changed the indications for lymph node radiation therapy keeping similar efficacy with reduced toxicity. Indications for radiation therapy after neoadjuvant chemotherapy remain based on pre-chemotherapy staging pending the results of ongoing randomized studies. The addition of a boost to the tumor bed significantly reduces the risk of local recurrence, but the magnitude of this benefit decreases with increasing age. The main risk factors for local recurrence are young age, the associated extended ductal in situ component, hormone receptor negative and high-grade status. The results of the simultaneous integrated boost (SIB) seem similar with normo- or moderately hypofractionated radiation therapy regimen.

Mapping the location of local and regional recurrences according to breast cancer surgery and radiation therapy: Results from EORTC 22922/10925

The purpose of this study is to evaluate the influence of the extent of surgery and radiation therapy (RT) on the rates and sites of local (LR) and regional recurrences (RR) in the EORTC 22922/10925 trial.

PATIENTS AND METHODS

All data were extracted from the trial's individual patients' case report forms (CRF) and analysed with a median follow-up of 15.7 years. Cumulative incidence curves were produced for LR and RR accounting for competing risks: an exploratory analysis of the effect of the extent of surgical and radiation treatments on LR rate was conducted using the Fine & Gray model accounting for competing risks and adjusted for baseline patient and disease characteristics. The significance level was set at 5%, 2-sided. Frequency tables were used to describe the spatial location of LR and RR.

RESULTS

Out of 4004 patients included in the trial, 282 (7%) patients experienced LR and 165 (4.1%) RR, respectively. Cumulative incidence rate of LR at 15 years was lower after mastectomy (3.1%) compared to BCS + RT (7.3%) (F&G: HR (Hazard Ratio) = 0.421, 95%CI = 0.282-0.628, p-value < 0.0001). LR were similar up to 3 years for both mastectomy and BCS but continued to occur at a steady rate for BCS + RT, only. The spatial location of the recurrence was related to the locoregional therapy applied and the absolute gain of RT correlated to stage of disease and extent of surgery.

CONCLUSIONS

The extent of locoregional therapies impacts significantly on LR and RR rates and spatial location.

Radiotherapy for oral cavity cancers

Intensity modulated radiation therapy and brachytherapy are standard techniques of irradiation for the treatment of oral cavity cancers. These techniques are detailed in terms of indication, planning, delineation and selection of the volumes of interest, dosimetry and patients positioning control. This is an update of the guidelines of the French Society of Radiotherapy Correspondence.

Radiotherapy of breast cancer

Adjuvant radiotherapy is an essential component of the treatment of breast cancer. After conservative surgery for an infiltrating carcinoma, radiotherapy must be systematically performed, regardless of the characteristics of the disease, because it decreases the rate of local recurrence and by this way, specific mortality. A boost dose over the tumour bed is required if the patient is younger than 50 years-old. Partial breast irradiation could be routinely proposed as an alternative to whole breast irradiation, but only in selected and informed patients. For ductal carcinoma in situ, adjuvant radiotherapy must be also systematically performed after lumpectomy. After mastectomy, chest wall irradiation is required for pT3-T4 tumours and if there is an axillary nodal involvement, whatever the number of involved lymph nodes. After neoadjuvant chemotherapy and mastectomy, in case of pN0 disease, chest wall irradiation is recommended if there is a clinically or radiologically T3-T4 or node positive disease before chemotherapy. Axillary irradiation is recommended only if there is no axillary surgical dissection and a positive sentinel lymph node. Supra- and infraclavicular irradiation is advised in case of positive axillary nodes. Internal mammary irradiation must be discussed case by case, according to the benefit/risk ratio (cardiac toxicity). Hypofractionation regimens (42.5Gy in 16 fractions, or 41,6Gy en 13 or 40Gy en 15) are equivalent to conventional irradiation and must prescribe after tumorectomy in selected patients. Delineation of the breast, the chest wall and the nodal areas are based on clinical and radiological evaluations. 3D-conformal irradiation is the recommended technique, intensity-modulated radiotherapy must be proposed only in specific clinical situations. Respiratory gating could be useful to decrease the cardiac dose. Concomitant administration of chemotherapy in unadvised, but hormonal treatment could be start with or after radiotherapy.

Radiotherapy for nasopharyngeal cancer

Nasopharyngeal cancers are a rarity in France. Radiotherapy is the cornerstone of treatment, frequently combined with chemotherapy. The technical modality of radiotherapy is complex in this disease, which is located in the vicinity of numerous organs at risk. In this article, we will present the updated guidelines of the French society for radiation oncology (Société française de radiothérapie oncologique, SFRO) on the indications, and technical details of radiotherapy in nasopharyngeal cancers.

Quality assurance program and early toxicities in the phase III BONBIS randomized trial evaluating the role of a localized radiation boost in ductal carcinoma in situ

PURPOSE

To describe the quality assurance (QA) program and early toxicities in the phase III randomized trial BONBIS (NCT00907868) on the role of a localized radiation boost in ductal carcinoma in situ (DCIS).

MATERIALS AND METHODS

From November 2008 to July 2014, 2004 patients were randomized in arm A (only whole breast radiotherapy, WBRT) and arm B (WBRT + boost). The QA program involved 44 participant centers that performed the dummy run (DR). Compliance and uniformity of clinical target volume (CTV) delineations, and dose prescription and delivery according to the BONBIS trial radiotherapy guidelines were analyzed. Acute toxicities (during and up to 3 months after radiotherapy completion, NCI-CTCAE v3.0 classification) were evaluated in 1929 patients.

RESULTS

The differences in whole breast CTV (CTV1) and planning target volume (PTV1) were ≤10%, and the differences in boost CTV (CTV2) and PTV (PTV2) were ≥20% compared with the reference DR values; 95% of the prescribed dose encompassed 98.7% and 100% of the median CTV1 and CTV2. Grade ≥2 breast erythema (38.3% vs. 22.4% of grade 2 and 5.4% vs. 2.1% of grade 3, p < 0.001), grade ≥2 dermatitis (2.8% vs. 0.7%, p < 0.001), and grade 2 hyperpigmentation (6.9% vs. 3.6%, p = 0.005) were more frequent in arm B than arm A. No acute lung or cardiac toxicity was observed. Smoking history, large breast size, and large breast CTV were strong predictive factors of grade ≥2 acute skin toxicities.

CONCLUSIONS

The QA program showed deviations in breast and tumor bed delineation. The boost significantly increased acute skin toxicities.

A priori quality assurance using a benchmark case of the randomized phase 2 GORTEC 2014-14 in oligometastatic head and neck cancer patients

PURPOSE

A Benchmark Case (BC) was performed as part of the quality assurance process of the randomized phase 2 GORTEC 2014-14 OMET study, testing the possibility of multisite stereotactic radiation therapy (SBRT) alone in oligometastatic head and neck squamous cell carcinoma (HNSCC) as an alternative to systemic treatment and SBRT.

MATERIAL AND METHODS

Compliance of the investigating centers with the prescription, delineation, planning and evaluation recommendations available in the research protocol was assessed. In addition, classical dosimetric analysis was supplemented by quantitative geometric analysis using conformation indices.

RESULTS

Twenty centers participated in the BC analysis. Among them, four major deviations (MaD) were reported in two centers. Two (10%) centers in MaD had omitted the satellite tumor nodule and secondarily validated after revision. Their respective DICE indexes were 0.37 and 0 and use of extracranial SBRT devices suboptimal There were significant residual heterogeneities between participating centers, including those with a similar SBRT equipment, with impact of plan quality using standard indicators and geometric indices.

CONCLUSION

A priori QA using a BC conditioning the participation of the clinical investigation centers showed deviations from good SBRT practice and led to the exclusion of one out of the twenty participating centers. The majority of centers have demonstrated rigorous compliance with the research protocol. The use of quality indexes adds a complementary approach to improve assessment of plan quality.

Histosurgical mapping of endoscopic endonasal surgery of sinonasal tumours to improve radiotherapy guidance

PURPOSE

Endoscopic endonasal surgery (EES) is becoming a standard for most malignant sinonasal tumours. Margin analysis after piecemeal resection is complex and optimally relies on accurate histosurgical mapping. Postoperative radiotherapy may be adapted based on margin assessment mapping to reduce the dose to some sinonasal subvolumes. We assessed the use of histosurgical mapping by radiation oncologists (RO).

MATERIAL AND METHODS

A French practice survey was performed across 29 ENT expert RO (2 did not answer) regarding integration of information on EES, as well as quality of operative and pathology reportsto refine radiotherapy planning after EES. This was assessed through an electronic questionnaire.

RESULTS

EES was ubiquitously performed in France. Operative and pathology reports yielded accurate description of EES samples according to 66.7% of interviewed RO. Accuracy of margin assessment was however insufficient according to more than 40.0% of RO. Additional margins/biopsies of the operative bed were available in 55.2% (16/29) of the centres. In the absence of additional margins, quality of resection after EES was considered as microscopically incomplete in 48.3% or dubious in 48.3% of RO. As performed, histosurgical mapping allowed radiotherapy dose and volumes adaptation according to 26.3% of RO only.

CONCLUSIONS

Standardized histosurgical mapping with margin and additional margin analysis could be more systematic. Advantages of accurate EES reporting could be dose painting radiotherapy to further decrease morbidity in sinonasal tumours.

Recommendations for postoperative radiotherapy in head & neck squamous cell carcinoma in the presence of flaps: A GORTEC internationally-reviewed HNCIG-endorsed consensus

INTRODUCTION

Head and neck reconstructive surgery using a flap is increasingly common. Best practices and outcomes for postoperative radiotherapy (poRT) with flaps have not been specified. We aimed to provide consensus recommendations to assist clinical decision-making highlighting areas of uncertainty in the presence of flaps.

MATERIAL AND METHODS

Radiation, medical, and surgical oncologists were assembled from GORTEC and internationally with the Head and Neck Cancer International Group (HNCIG). The consensus-building approach covered 59 topics across four domains: (1) identification of postoperative tissue changes on imaging for flap delineation, (2) understanding of tumor relapse risks and target volume definitions, (3) functional radiation-induced deterioration, (4) feasibility of flap avoidance.

RESULTS

Across the 4 domains, international consensus (median score ≥ 7/9) was achieved only for functional deterioration (73.3%); other consensus rates were 55.6% for poRT avoidance of flap structures, 41.2% for flap definition and 11.1% for tumor spread patterns. Radiation-induced flap fibrosis or atrophy and their functional impact was well recognized while flap necrosis was not, suggesting dose-volume adaptation for the former. Flap avoidance was recommended to minimize bone flap osteoradionecrosis but not soft-tissue toxicity. The need for identification (CT planning, fiducials, accurate operative report) and targeting of the junction area at risk between native tissues and flap was well recognized. Experts variably considered flaps as prone to tumor dissemination or not. Discrepancies in rating of 11 items among international reviewing participants are shown.

CONCLUSION

International GORTEC and HNCIG-endorsed recommendations were generated for the management of flaps in head and neck radiotherapy. Considerable knowledge gaps hinder further consensus, in particular with respect to tumor spread patterns.

[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.

Internal mammary and medial supraclavicular lymph node chain irradiation in stage I-III breast cancer (EORTC 22922/10925): 15-year results of a randomised, phase 3 trial

BACKGROUND

10-year results from several studies showed improved disease-free survival and distant metastasis-free survival, reduced breast cancer-related mortality, and variable effects on overall survival with the addition of partial or comprehensive regional lymph node irradiation after surgery in patients with breast cancer. We present the scheduled 15-year analysis of the European Organisation for Research and Treatment of Cancer (EORTC) 22922/10925 trial, which aims to investigate the impact on overall survival of elective internal mammary and medial supraclavicular (IM-MS) irradiation.

METHODS

EORTC 22922/10925, a randomised, phase 3 trial done across 46 radiation oncology departments from 13 countries, included women up to 75 years of age with unilateral, histologically confirmed, stage I-III breast adenocarcinoma with involved axillary nodes or a central or medially located primary tumour. Surgery consisted of mastectomy or breast-conserving surgery and axillary staging. Patients were randomly assigned (1:1) centrally using minimisation to receive IM-MS irradiation at 50 Gy in 25 fractions (IM-MS irradiation group) or no IM-MS irradiation (control group). Stratification was done for institution, menopausal status, site of the primary tumour within the breast, type of breast and axillary surgery, and pathological T and N stage. Patients and investigators were not masked to treatment allocation. The primary endpoint was overall survival analysed according to the intention-to-treat principle. Secondary endpoints were disease-free survival, distant metastasis-free survival, breast cancer mortality, any breast cancer recurrence, and cause of death. Follow-up is ongoing for 20 years after randomisation. This study is registered with ClinicalTrials.gov, NCT00002851.

FINDINGS

Between Aug 5, 1996, and Jan 13, 2004, we enrolled 4004 patients, of whom 2002 were randomly assigned to the IM-MS irradiation group and 2002 to the no IM-MS irradiation group. At a median follow-up of 15·7 years (IQR 14·0-17·6), 554 (27·7%) patients in the IM-MS irradiation group and 569 (28·4%) patients in the control group had died. Overall survival was 73·1% (95% CI 71·0-75·2) in the IM-MS irradiation group and 70·9% (68·6-72·9) in the control group (HR 0·95 [95% CI 0·84-1·06], p=0·36). Any breast cancer recurrence (24·5% [95% CI 22·5-26·6] vs 27·1% [25·1-29·2]; HR 0·87 [95% CI 0·77-0·98], p=0·024) and breast cancer mortality (16·0% [14·3-17·7] vs 19·8% [18·0-21·7]; 0·81 [0·70-0·94], p=0·0055) were lower in the IM-MS irradiation group than in the control group. No significant differences in the IM-MS irradiation group versus the control group were seen for disease-free survival (60·8% [95% CI 58·4-63·2] vs 59·9% [57·5-62·2]; HR 0·93 [95% CI 0·84-1·03], p=0·18), or distant metastasis-free survival (70·0% [67·7-72·2] vs 68·2% [65·9-70·3]; 0·93 [0·83-1·04], p=0·18). Causes of death between groups were similar.

INTERPRETATION

The 15-year results show a significant reduction of breast cancer mortality and any breast cancer recurrence by IM-MS irradiation in stage I-III breast cancer. However, this is not converted to improved overall survival.

FUNDING

US National Cancer Institute, Ligue Nationale contre le Cancer, and KWF Kankerbestrijding.

[Concurrent chemoradiotherapy for head neck cancers. Should organs at risk dose constraints be revisited ?]

Concurrent chemoradiotherapy improves the outcome of locally advanced head and neck cancers and the current reference chemotherapy is cisplatin. These results are obtained at the cost of increased toxicities. To limit the risk of toxicity, organ at riskdose constraints have been established starting with 2D radiotherapy, then 3D radiotherapy and intensity-modulated radiotherapy. Regarding grade ≥3 acute toxicities, the scientific literature attests that concurrent chemoradiotherapy significantly increases risks of mucositis and dysphagia. Constraints applied to the oral mucosa volume excluding the planning target volume, the pharyngeal constrictor muscles and the larynx limit this adverse impact. Regarding late toxicity, concurrent chemoradiotherapy increases significantly the risk of postoperative neck fibrosis and hearing loss. However, for some organs at risk, concurrent chemotherapy appears to increase late radiation induced effect, even though the results are less marked (brachial plexus, mandible, pharyngeal constrictor muscles, parotid gland). This additional adverse impact of concomitant chemotherapy may be notable only when organs at risk receive less than their usual dose thresholds and this would be vanished when those thresholds are exceeded as seems to be the situation for the parotid glands. Until the availability of more robust data, it seems appropriate to apply the principle of delivering dose to organs at risk as low as reasonably achievable.

[Impact of reconstructive or minimal invasive surgery on the assessment of current definitions of postoperative clinical target volume for head and neck cancers]

Advances in the reconstructive surgery and minimally invasive endonasal endoscopic surgery of head and neck is poorly evaluated in terms of their impact on radiotherapy planning and outcomes. These surgical advances have resulted in reduced morbidity with equivalent or better tumor control. In the absence of a recommendation on how to delineate target volumes in patients with flaps or to consider margins after endoscopic endonasal surgery, radiotherapy practices are inevitably heterogeneous. Efforts are needed to increase the therapeutic index of postoperative radiotherapy in these situations. We analysed the rare existing literature and outlined a preliminary basis for a recommendation. Strengthening of multidisciplinarity to accurately define target volumes in these complex and relatively new situations, and "delineation concertation meetings" between radiologists, surgeons and radiation oncologists could probably contribute to improved outcomes.

[Post-treatment follow-up of head and neck cancer patients]

Post-therapeutic follow-up of patients with head and neck cancer involves numerous professionals. The radiation oncologist should play an active role in this process. His oncological knowledge and technical expertise position him as a cornerstone for the detection of recurrences from the treated tumor, the research of second primary cancers and the screening of potential side-effects induced by the different treatments administered. To improve the benefits/costs ratio and allow good patient-compliance, follow-up programs should be built through close collaboration between the different contributors and planned according to a feasible schedule. Paraclinical exams must be arranged to respond to accurate objectives. Patient-education is essential to ensure the patient's full understanding and active participation. Finally, the transfer of the long-term follow-up of cancer survivors from specialists to primary care physicians is relevant but would require a prospective evaluation of its efficiency for this specific population.

Volumetric and dosimetric comparison of two delineation guidelines for the radiation treatment of laryngeal squamous cell carcinoma

•

The delineation of target volumes for Head and Neck IMRT is complex.

•

There have been several approaches for the delineation of the primary tumor clinical target volume: the anatomical guidelines, the geometric guidelines and more recently the international guidelines.

Purpose

Three methods have been recently proposed for the delineation of the primary tumor clinical target volume (CTV-P) in Head and Neck Cancers: the anatomic method popularized in the French literature by Lapeyre et al. the geometric methods proposed by the DAHANCA group, and more recently the international guidelines promoted by Grégoire et al. integrating the latter two. The aim of this study was to perform a volumetric and dosimetric comparison of the French and the International consensus methods in laryngeal SCC.

Patients and methods

Two radiation oncologists independently delineated the high dose and low dose primary tumor CTV in four patients with T2 or T3 N0-M0 laryngeal SCC following either the so-called French guidelines or the International guidelines. For the 4 cases, the GTV was delineated by a single radiation oncologist. Nodal CTVs were delineated by one radiation oncologist for the 4 cases using International guidelines. Dose optimization was then performed with VMAT (MONACO version 5.11) using 6 MeV photons. Differences in target volumes and dose distributions in OARs and PTVs were then evaluated with various metrics such as the DICE Similarity Coefficient and the homogeneity index.

Results

Major differences were observed in the CTV delineation between the 2 delineation methods for the low dose volumes and to a lower extend for the high dose volumes. These differences translated into variations in dose distribution favoring the International guidelines for decreasing dose to various OARs. Such differences toned down when dose distribution on the primary tumors PTVs and nodal PTVs were combined.

Conclusion

This study demonstrated large differences in CTV delineation between the 2 delineation guidelines. Such differences translated into differences in dose distribution.

A randomized trial of induction docetaxel-cisplatin-5FU followed by concomitant cisplatin-RT versus concomitant cisplatin-RT in nasopharyngeal carcinoma (GORTEC 2006-02)

Background

Concomitant chemotherapy (CT)-radiotherapy (RT) is a standard of care in locally advanced nasopharyngeal carcinoma (NPC) and a role for induction CT is not established.

Methods

Patients with locally advanced NPC, WHO type 2 or 3, were randomized to induction TPF plus concomitant cisplatin-RT or concomitant cisplatin-RT alone. The TPF regimen consisted of three cycles of Docetaxel 75 mg/m2 day 1; cisplatin 75 mg/m2 day 1; 5FU 750 mg/m2/day days 1-5. RT consisted of 70 Gy in 7 weeks plus concomitant cisplatin 40 mg/m2 weekly.

Results

A total of 83 patients were included in the study. Demographics and tumour characteristics were well balanced between both arms. Most of the patients (95%) in the TPF arm received three cycles of induction CT. The rate of grade 3-4 toxicity and the compliance (NCI-CTCAE v3) during cisplatin-RT were not different between both arms. With a median follow-up of 43.1 months, the 3-year PFS rate was 73.9% in the TPF arm versus 57.2% in the reference arm [hazard ratio (HR) = 0.44; 95% confidence interval (CI): 0.20-0.97, P = 0.042]. Similarly the 3 years overall survival rate was 86.3% in the TPF arm versus 68.9% in the reference arm (HR = 0.40; 95% CI: 0.15-1.04, P = 0.05).

Conclusion

In conclusion, several important aspects can be emphasized: the compliance to induction TPF was good and TPF did not compromise the tolerance of the concomitant RT-cisplatin phase. The improved PFS and overall survival rates needs to be confirmed by further trials.

Genomic alterations and radioresistance in breast cancer: an analysis of the ProfiLER protocol

BACKGROUND

Breast cancer (BC) patients with comparable prognostic features have heterogeneous outcomes, party related to a possible radiotherapy resistance leading to local-regional recurrences (LRR). The objective of the present study was to identify predictive molecular biomarkers of LRR of BC.

PATIENTS AND METHODS

Genetic profile of 146 BC patients' tumours included in the ProfiLER clinical trial (NC01774409) between 2013 and 2016 were analysed using next-generation-sequencing and comparative-genomic-hybridization tests. Patients and tumour characteristics were retrospectively collected and analysed for association with genomic rearrangements (mutations, amplification, deletions). Only gene alterations observed in >3% of the tumours were selected.

RESULTS

A total of 193 genomic rearrangements were identified, and 16 were observed in >3% of tumours. One was statistically correlated to the risk of local relapse. A median loco-regional progression-free survival (LRPFS) of 23.6 years was reported for PIK3CA mutation carriers (n = 31, 21.2%) versus 9.9 years for PIK3CA wild-type patients (HR 0.27, 95% CI 0.12-0.65, P = 0.002 in univariate analysis). PIK3CA mutation was identified as an independent protective factor on LRR using multivariate analysis (HR 0.29, 95% CI 0.09-0.99, P = 0.047). All other mutations, amplifications or deletions were not found associated with LRPFS.

CONCLUSION

PIK3CA mutation was associated with a lower risk of local relapse in this population of BCs. This is consistent with recent studies suggesting PIK3CA to be part of biological pathways impacting the radiosensitivity.

[Description of the GORTEC 2017-03 study: Postoperative stereotactic radiotherapy for early stage oropharyngeal and oral cavity cancer with high risk margin (PHRC-K-16-164)]

The GORTEC 2017-03-Stereo-postop study is a phase 2, multicentric, nationwide study, funded by the hospital clinical research program (PHRC). The sponsor is Centre Jean-Perrin in Clermont-Ferrand, in partnership with the GORTEC. The principal investigators are Dr J Biau and Dr M Lapeyre. The main objective is to study severe late toxicity of postoperative stereotactic radiotherapy (6×6Gy) for early stage oropharyngeal and oral cavity cancer with high risk margins. The secondary objectives include acute toxicity, efficacy, nutritional impact and quality of life. The population is adult patients, with pT1 or pT2 squamous cell carcinoma of the oropharynx or oral cavity (except lips), without indication of neck irradiation or concomitant chemotherapy, with at risk margin (R1, less than 5mm or uncertain). Ninety patients will be included over a 2-year period; this was calculated to limit the rate of 2-year severe toxicity at 5 to 15%, with a 2-year local control of at least 80 to 90%. If this study is considered as positive, stereotactic radiotherapy (6×6Gy) could become the third therapeutic option, with brachytherapy and normofractionated intensity-modulated radiotherapy (IMRT), for postoperative irradiation of oropharyngeal and oral cavity cancer with high risk margins.

Combined abiraterone, salvage prostate bed radiotherapy and LH-RH agonists (CARLHA) in biochemically-relapsing prostate cancer patients following prostatectomy: A phase I study of the GETUG/GEP

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Background: Salvage radiotherapy (RT) plus 6 months LH-RH therapy (ADT) improves biochemical relapse free survival in men with rising PSA following prostatectomy. Abiraterone acetate (Aa) increases overall survival in metastatic prostate cancer. We aimed to establish the toxicity of adding Aa combined with salvage RT and 6 months goserilin (Gos). Methods: We enrolled pT2-pT4a pN0 prostate cancer patients (pts) with rising PSA (0.2 to <2.0 μg/l) following radical prostatectomy. The primary endpoint was to determine the Maximum Tolerated Dose and recommended dose of Aa during RT plus Gos, two dose levels tested : 1 (750mg) and 2 (1000 mg). Two different schemes were explored: Sheme A: Aa (1000 mg) and predisone (10 mg) were given orally during 1 month to salvage IMRT (66 Gy in 33 fractions). The first day of irradiation, Aa is reduced to level 1 or 2 and 10.8 mg Gos is injected (sc). In sheme B, Gos is injected the first day (1 month before starting RT). Results: We recruited 9 + 9 pts in scheme A and B respectively. In scheme A, Testosterone (Tst) levels declined to castration level (<0.5ng/ml) after 10 days . Two/9 pts did not achieve castration levels at 30 days. Median LH levels increased to 10.4 (D10) and 12.5 IU/l (D20). At dose level 1, 4/9 pts (44%) experienced grade 3 hepatitis, occurring prior to RT or during RT (8 Gy, 36 and 54 Gy). We hypothesized that this unexpected liver toxicity was related to the LH increase during the first month (Aa administration without Gos). Therefore, we modified LH-RH administration (scheme B) and recruited 9 more pts. Tst levels dropped to undetectable at day 6, while median LH levels decreased to 6.1 (D10) and 1.7 IU/l (D20). At dose level 1 (3 + 3 pts), no grade 3 liver toxicity was reported. No other grade 3 toxicity was recorded. At dose level 2, 2/3 pts had grade 3 hepatitis occurring during RT. CYP17 polymorphism did not correlate with liver toxicity. Conclusions: The recommended dose of Aa combined to short-term androgen deprivation and salvage RT is 750 mg. Aa alone did lead to castration levels in 22% of pts.An unexpected high frequency of grade 3 liver toxicity was observed. Clinical trial information: NCT01780220.

Induction chemotherapy with docetaxel, cisplatin, 5 FU, followed by radiotherapy plus cisplatin or cetuximab, in organ preservation in piriform sinus carcinomas

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Background: Only few studies report organ preservation in piriform sinus carcinomas (PSC), with no publication on induction chemotherapy (IC) with docetaxel, cisplatine, 5FU (DCF) followed by radiotherapy plus cisplatin (RTCis) or cetuximab (RTCet). We assessed compliance, survival and organ preservation after IC by DCF followed by RTCis or RTCet in a retrospective multicentric review of patients (pts) with advanced PSC. Methods: We analyzed retrospectively 88 pts with advanced PSC treated between 2005 and 2011 in 3 tertiary care centers with organ preservation protocol strategy ongoing in each center. DCF was followed by RTCet (56.5%) in 1 center and by RTCis(42%) in the 2 others. Primary endpoints were acute toxicity and compliance to IC and RTCis compliance compared with RTCet. Secondary endpoints were overall survival (OS), disease free survival (DFS) and laryngectomy free survival (LFS). Results: Within the 88 pts, 21.6% were stage III and 72.7% stage IV; 81% completed the full course of IC. For 64.8% of pts no toxicity was reported. The main side effect observed was neutropenia (18.2%). Two deaths (2%) were directly related to the IC. Concerning the radiotherapy, 59% of the pts had full dose concomitant cisplatin versus 85% with cetuximab (p<0.001). Mean follow up was 23.5 months. At 5 years, OS rate was 35.5%, [CI 95% 24.6%-50.7%]. At 4 years DFS rate was 24% [CI 95% 15.5%-38%]. Factors affecting survival were IC response (ICR) (p<0.001) and stage of the disease (stage II>stage IV, p<0.001). No significant difference in survival was found between patients with RTCis or RTCet. At 4 years, LFS rate was 73% [IC 95% 56%-87.6%]. Factor affecting this LFS rate was ICR (p<0.05). Conclusions: IC with DPF followed by RTCis or RTCet allowed high organ preservation rates with acceptable toxicities. Cetuximab seemed to be better tolerated than cisplatin, improving compliance to the treatment. OS favorably compared with historical data of concurrent chemoradiation

Compliance and efficacy of induction chemotherapy with cisplatin, docetaxel, and fluorouracil followed by radiotherapy plus cisplatin or cetuximab for locally advanced oropharyngeal tumours

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Background: This study aimed to assess compliance and survival after induction chemotherapy (IC) with docetaxel, cisplatin, fluorouracil (DCF) followed by radiotherapy plus cisplatin (RTCis) or radiotherapy plus cetuximab (RTCet) in a retrospective multicentric series of 121 patients with locally advanced oropharyngeal cancer. One of the issues of these chemotherapy regimens is the toxicity that adversely affects the compliance to the concomitant radiochemotherapy treatment. We also evaluated feasibility and completion of radiochemotherapy treatment comparing efficacy and toxicity between RTCet and RTCis. Methods: Multicentric retrospective review of 121 consecutive patients with non resectable or non operable oropharyngeal carcinomas treated between 2005 and 2011 in 3 tertiary care centers with protocol ongoing in each center. In one center DCF, is followed by RTCet, in the 2 other centers, DCF is followed by RTCis. Primary endpoints were acute toxicity of IC and compliance to the RTCis compared with RTCet. Secondary endpoints were overall survival, disease free survival and locoregional control. Results: Within the 121 patients, 20.7% were stage III and 79.3% were stage IV. 81.8% of the patients completed the full course of IC. 50% of the patients had full dose concomitant cisplatin versus 77% of the patients that had full dose concomitant cetuximab (p=0.017). Mean follow up was 23.5 months. Median overal survival was 20.7 months, median disease free survival was 18.6 months. The 3 and 5 year overall survival rates were respectively 52.5% and 46.4%. The 3 and 5 year disease free survival rates were 44.2% and 38.3%. The only significant factor affecting survival was IC response (p<0.05). No statistically significant difference in survival was found between patients with concomitant cisplatin or cetuximab. Conclusions: Induction chemotherapy with DCF followed by RTCis or RTCet allowed good survival rates with acceptable toxicities. Cetuximab seemed to be better tolerated than cisplatin improving compliance to the treatment.

Radiotherapy (RT) potentiation with weekly (q1w) or standard every 3 weeks (q3w) cisplatin chemotherapy (CT) for locally advanced head and neck squamous cell carcinoma (HNSCC)

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Background: Q3w CT is standard RT potentiation for HNSCC but its toxicity requires to look for new treatment’s modalities. The aim was to explore if q1w CT could be a safe and effective alternative. Methods: Patients (pts) treated by chemoradiation (CT-RT) for a HNSCC were retrospectively included. Study population was first described. Then overall (OS) and progression-free survival since the RT onset were performed. Survival distributions were estimated by Kaplan-Meier method and compared between CT groups using the Log-Rank test. Prognostic effect of CT group was explored using Cox model. Results: 266 pts treated between January 2004 and December 2008 were included: 170 and 96 pts respectively received q1w and q3w CT. At diagnosis, 46% had oropharynx lesions, 20% larynx, 17% hypopharynx and 14% oral cavity. 70% pts experienced surgery, 39% CT induction and a median dose of radiation of 64 Gy without any significant difference between CT groups. However, median age at diagnosis was significantly different between q1w and q3w CT (58 vs 54, p<0.001) as well as alcohol consumption (79% vs 68, p=0.047), stage at diagnosis (30%-60% stage III-IV vs 13% -80%, p=0.003), IMRT use (4% vs 13%, p=0.011) and median weight before RT (66 kg vs71kg, p=0.014). Q3w CT was more toxic than q1w in terms of weight loss (87% vs 75%, p=0.012), renal failure (50% vs 35%, p=0.022), worse CT plan completion (42% vs 66%, p<0.001). Moreover, grade 3/4 toxicities, such as mucositis (34% vs 13%, p<0.001) and dermatitis (7% vs 1%, p=0.012), were more frequent. More pts needed parenteral nutrition (10% vs 2%, p=0.008), analgesics (91% vs 70%, p<0.001), secondary hospitalization (31% vs 8%, p<0.001), RT interruption >= 3 days (8% vs 2%, p=0.037) and had long-term toxicities (24% vs 12%, p=0.014). With a median follow-up of 42 months 95% CI [36.8-48.8], a trend in favour of q3w CT was found:2-years OS of 83% (95% CI [73-90]) vs 74% (95% CI [66-80]), p=0.089. However, after adjustment on prognostic factors CT group was not significantly associated with OS nor with PFS. Conclusions: Q1w RT-CT is safer than q3w and may be as efficient. Follow-up data will be updated to reinforce efficacy results.

Nonstandard first-line therapy and survival in patients (pts) with recurrent/metastatic head and neck cancer (RMHNSCC): Experience of 194 pts in a single institution

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Background: With the standard first line association platinum 5FU and cetuximab, median overall survival (OS) for RMHNSCC was 10.1 months (95% CI [8.6 – 11.2]) (N Engl J Med. 359:1116). Due to the toxicity of this treatment we often offer alternative therapy to our pts. This work aimed to evaluate impact of different 1st line treatment on OS. Methods: With the standard first line association platinum 5FU and cetuximab, median overall survival (OS) for RMHNSCC was 10.1 months (95% CI [8.6 – 11.2]) (N Engl J Med. 359:1116). Due to the toxicity of this treatment we often offer alternative therapy to our pts. This work aimed to evaluate impact of different 1st line treatment on OS. Results: At initiation of palliative chemotherapy, median age was 62 [29-87]; PS was 0, 1, 2, 3 in 13%, 59%, 16% and 11% of pts, respectively. First line chemotherapy consists in combination cisplatin+taxanes (CIST) 24%, caboplatin+taxanes (CART) 33%, cisplatin or carboplatin without taxanes (NOT) 15% or others (OTH) 28%. Median OS was estimated to 9.6 months CI95%=[8.1-11.4], with 39% of pts; CI95%=[32-47] still alive at 1-year. Second line of treatment has been initiated in 61% of pts. Some of them have even been able to have up to 3, 4 or more than 4 lines of treatment in 19%, 11% and 4% of pts, respectively. In the subgroup analysis, which represents a population similar to those included in [ref1], first line chemotherapy was CIST, CART, NOT or OTH in 30%, 30%, 18% and 22%, respectively. Median OS was 13.0 months, CI95%=[11.2-17.7] reaching up to 15.3 months for CIST subgroup. Second line of treatment was initiated in 73% of pts, with 20%, 15% and 5% of pts having a third, a fourth, and a fifth line, respectively. Conclusions: We can reach for unselected pts the best OS published in phase III studies. The use in first line of combination of platinum and taxanes, followed by monotherapies with cetuximab, capecitabine and methotrexate allows reaching OS of 13 months.

Correlation of SMAD4 mutational status and local or metastatic progression in patients with pancreatic cancer

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Background: Pancreatic cancer remains resistant to many key cytotoxic chemotherapeutic agents and novel targeted therapies. The molecular heterogeneity of this cancer may account for therapy failures to date, although the growing arsenal of novel targeted agents could translate into patient survival. A better understanding of the cellular and molecular features of advanced disease will afford new opportunities for investigation, therapeutic intervention and clinical management of patients afflicted with pancreatic cancer. Methods: This study examined the expression profiles of Smad4 in 45 samples of surgically resected pancreatic cancer. Of these 45 patients, 32 underwent pancreaticoduodenectomy. The clinicopathological parameters, the histologic features were determined and correlated to the stage at initial diagnosis, patterns of failure (locally advanced v metastatic disease) and the status SMAD4 genes. Results: Among the 45 patients, 40% of patients died with metastatic disease and 15 % died with locally advanced evolution. SMAD4 genetic status was determined in 25 patients and seems to be correlated with a high grade histologic features and progression to metastasis. Complementary data about correlation between the mutational status of SMAD4 and survival will be presented during congress. Conclusions: SMAD4 gene inactivation seems to be associated with poorer prognosis and disease progression. Prospective validation of SMAD4 as a predictive biomarker may personalize treatment strategies for patients with pancreatic cancer.