Cost-effectiveness of weekly adaptive radiotherapy versus standard IMRT in head and neck cancer alongside the ARTIX trial

BACKGROUND AND PURPOSE

We performed a cost-effectiveness analysis (CEA) comparing an adaptive radiotherapy (ART) strategy, based on weekly replanning, aiming to correct the parotid gland overdose during treatment and expecting therefore to decrease xerostomia, when compared to a standard IMRT.

MATERIALS AND METHODS

We conducted the ARTIX trial, a randomized, parallel-group, multicentric study comparing a systematic weekly replanning ART to a standard IMRT. The primary endpoint was the frequency of xerostomia at 12 months, measured by stimulating salivary flow with paraffin. The CEA was designed alongside the ARTIX trial which was linked to the French national health data system (SNDS). For each patient, healthcare consumptions and costs were provided by the SNDS. The reference case analysis was based on the primary endpoint of the trial. Sensitivity and scenario analyses were performed.

RESULTS

Of the 129 patients randomly assigned between 2013 and 2018, only 2 records were not linked to the SNDS, which provides a linkage proportion of 98.4%. All of the other 127 records were linked with good to very good robustness. On the intent-to-treat population at 12 months, mean total costs per patient were €41,564 (SD 23,624) and €33,063 (SD 16,886) for ART and standard IMRT arms, respectively (p = 0.033). Incremental cost effectiveness ratio (ICER) was €162,444 per xerostomia avoided. At 24 months, ICER was €194,521 per xerostomia avoided. For both progression-free and overall survival, ART was dominated by standard IMRT.

CONCLUSION

The ART strategy was deemed to be not cost-effective compared with standard IMRT for patients with locally advanced oropharyngeal cancer.

Prognostic impact of post-treatment FDG PET/CT in anal canal cancer: A prospective study

BACKGROUND AND PURPOSE

The aim of our prospective study was to assess the prognostic value of 18F-FDG PET/CT performed two months post treatment for anal canal neoplasm.

POPULATION AND METHODS

Consecutive patients with histologically proved anal cancer, with 18F-FDG PET/CT pre and two months post treatment were included. Patients were not previously treated for this neoplasm and then received radiotherapy ± chemotherapy. Clinical and pathologic data were collected and for 18F-FDG PET/CT visual and quantitative analysis (standardized uptake value, metabolic volume) were performed; response was classified according to EORTC and PERCIST criteria. The results were assessed for disease free survival and local recurrence free survival using the log-Rank test RESULTS: From December 2014 to September 2019, 94 consecutive patients were screened and 78 were included in this study. Median follow-up was 51 months. Two months post treatment, 37 patients (47.4%) had a complete radiological response according to both EORTC and PERCIST criteria, 66 patients (84.6%) had a clinical complete response. For disease free survival, the prognostic value of complete response was statistically significant (p=0.02) with 18F-FDG PET/CT and with clinical examination (p<0.001). For local recurrence free survival, the prognostic value with 18F-FDG PET/CT was lower (p=0.04) than clinical examination (p < 0.007).

CONCLUSION

While clinical examination remains the gold standard for post treatment evaluation in anal cancer, 18F-FDG PET/CT has a statistically significant prognostic value. These two assessments could be combined to improve early evaluation.

Weekly Adaptive Radiotherapy vs Standard Intensity-Modulated Radiotherapy for Improving Salivary Function in Patients With Head and Neck Cancer: A Phase 3 Randomized Clinical Trial

Importance

Xerostomia is a major toxic effect associated with intensity-modulated radiotherapy (IMRT) for oropharyngeal cancers.

Objective

To assess whether adaptive radiotherapy (ART) improves salivary function compared with IMRT in patients with head and neck cancer.

Design, Setting, and Participants

This phase 3 randomized clinical trial was conducted in 11 French centers. Patients aged 18 to 75 years with stage III-IVB squamous cell oropharyngeal cancer treated with chemoradiotherapy were enrolled between July 5, 2013, and October 1, 2018. Data were analyzed from November 2021 to May 2022.

Interventions

The patients were randomly assigned (1:1) to receive standard IMRT (without replanning) or ART (systematic weekly replanning).

Main Outcomes and Measures

The primary end point was the frequency of xerostomia, measured by stimulating salivary flow with paraffin. Secondary end points included salivary gland excretory function measured using technetium-99m pertechnetate scintigraphy, patient-reported outcomes (Eisbruch xerostomia-specific questionnaire and the MD Anderson Symptom Inventory for Head and Neck Cancer questionnaire), early and late toxic effects, disease control, and overall and cancer-specific survival.

Results

A total of 132 patients were randomized, and after 1 exclusion in the ART arm, 131 were analyzed: 66 in the ART arm (mean [SD] age at inclusion, 60 [8] years; 57 [86.4%] male) and 65 in the standard IMRT arm (mean [SD] age at inclusion, 60 [8] years; 57 [87.7%] male). The median follow-up was 26.4 months (IQR, 1.2-31.3 months). The mean (SD) salivary flow (paraffin) at 12 months was 630 (450) mg/min in the ART arm and 584 (464) mg/min in the standard arm (P = .64). The mean (SD) excretory function of the parotid gland at 12 months, measured by scintigraphy, improved in the ART arm (48% [17%]) compared with the standard arm (41% [17%]) (P = .02). The 2-year-overall survival was 76.9% (95% CI, 64.7%-85.4%) in both arms.

Conclusions and Relevance

This randomized clinical trial did not demonstrate a benefit of ART in decreasing xerostomia compared with standard IMRT. No significant differences were found in secondary end points except for parotid gland excretory function, as assessed by scintigraphy, or in survival rates.

Trial Registration

ClinicalTrials.gov Identifier: NCT01874587.

Enteral Nutrition during Radiotherapy for Oropharyngeal Cancers: Prevalence and Prognostic Factors Based on HPV Status (A GETTEC Study)

Nutritional support during radiotherapy is crucial to tolerating and completing oropharyngeal squamous cell carcinoma (OPSCC) treatment. The impact of HPV status on nutritional support is debated. The objective was to evaluate the rate of Reactive Feeding Tube (RFT) use and determine its prognostic factors during definitive radiotherapy for OPSCC. All OPSCC patients treated from 2009 to 2014 were included in this multicentric retrospective study. The impact of tumor p16 status on the risk of RFT was assessed through multivariate analyses. Among the 543 patients, 103 patients required an RFT (19.0%). The use of RFT differed between centers (5% to 32.4%). In multivariate analysis, only tongue base involvement and concurrent chemotherapy were significantly associated with RFT (OR = 2.18 and 3.7, respectively). Tongue base involvement and concomitant chemotherapy were prognostic factors for RFT. HPV status was not a prognostic factor for enteral nutrition during radiotherapy for OPSCC.

Failure of Initial Curative Treatment for Non-Metastatic Anal Squamous Cell Carcinoma: From Prognostic Factors Analysis to Stratified Treatment

In squamous cell anal canal neoplasms, persistent disease or recurrence after initial chemoradiotherapy are not the rule, yet their occurrence deserves to be analyzed to better identify prognostics factors. The aim of our study was to describe the patterns of failures of the initial treatment, their subsequent evolution and to identify prognostic factors in these relapsed patients. All patients with non-metastatic anal squamous cell carcinoma initially treated with curative intent at the Centre Antoine Lacassagne between 1999 and 2019, and who presented persistent disease or recurrence were analyzed. The median follow-up was 44 months. Univariate and multivariate analyses were performed to identify prognostic factors. From our database of 528 patients, 77 patients were eligible: 25 with persistent disease and 52 with recurrence after complete response. The median overall survival was 39 months (95% CI: 25.5-52.3 months) from the date of treatment failure. In univariate analysis, prognostic factors were gender, initial lymph node status, type of failure, response to treatment's failure. In multivariate analysis, only female gender remained statistically significant (HR 0.43- P=0.016). 32% of patients with persistent disease had metastatic status. 17.3% and 5.8% of recurrences respectively occurred after three and five years of follow-up. Systematic imaging could be performed after initial treatment because of distant lesions in one third of patients with persistent disease. The follow-up should not be interrupted before five years, given the significant frequency of late recurrences. In multivariate analysis, only female gender was statistically significant. Stratified treatment based on prognostic factors could be envisaged, the details of which remain to be defined.

Better preservation of erectile function in localized prostate cancer patients with modern proton therapy: Is it cost-effective?

BACKGROUND

Stereotactic body radiation therapy (SBRT) has gradually been recognized as favorable curative treatment for localized prostate cancer (PC). However, the high rate of erectile dysfunction (ED) after traditional photon-based SBRT remains an ongoing challenge that greatly impacts the quality of life of PC survivors. Modern proton therapy allows higher conformal SBRT delivery and has the potential to reduce ED occurrence but its cost-effectiveness remains uninvestigated.

METHODS

A Markov decision model was designed to evaluate the cost-effectiveness of proton SBRT versus photon SBRT in reducing irradiation-related ED. Base-case evaluation was performed on a 66-year-old (median age of PC) localized PC patient with normal pretreatment erectile function. Further, stratified analyses were performed for different age groups (50, 55, 60, 65, 70, and 75 years) and threshold analyses were conducted to estimate cost-effective scenarios. A Chinese societal willingness-to-pay (WTP) threshold (37,653 US dollars [$])/quality-adjusted life-year [QALY]) was adopted.

RESULTS

For the base case, protons provided an additional 0.152 QALY at an additional cost of $7233.4, and the incremental cost-effectiveness ratio was $47,456.5/QALY. Protons was cost-effective for patients ≤62-year-old at the WTP of China (≤66-year-old at a WTP of $50,000/QALY; ≤73-year-old at a WTP of $100,000/QALY). For patients at median age, once the current proton cost ($18,000) was reduced to ≤$16,505.7 or the patient had a life expectancy ≥88 years, protons were cost-effective at the WTP of China.

CONCLUSIONS

Upon assumption-based modeling, the results of current study support the use of proton SBRT in younger localized PC patients who are previously potent, for better preservation of erectile function. The findings await further validation using data from future comparative clinical trials.

Cost-effectiveness of using protons for breast irradiation aiming at minimizing cardiotoxicity: A risk-stratification analysis

Background

Incidental exposure of the heart to ionizing irradiation is associated with an increased risk of ischemic heart disease and subsequent fatality in patients with breast cancer after radiotherapy. Proton beam therapy can limit the heart dose in breast irradiation to a negligible level. However, compared with conventional photon modality, proton breast irradiation is more expensive. In this study, we performed cost-effectiveness analyses to identify the type of patients who would be more suitable for protons.

Methods

A Markov decision model was designed to evaluate the cost-effectiveness of protons vs. photons in reducing the risk of irradiation-related ischemic heart disease. A baseline evaluation was performed on a 50-year-old woman patient without the preexisting cardiac risk factor. Furthermore, risk-stratification analyses for photon mean heart dose and preexisting cardiac risk were conducted on 40-, 50-, and 60-year-old women patients under different proton cost and willingness-to-pay (WTP) settings.

Results

Using the baseline settings, the incremental effectiveness (protons vs. photons) increased from 0.043 quality-adjusted life-year (QALY) to 0.964 QALY when preexisting cardiac risk increased to 10 times its baseline level. At a proton cost of 50,000 US dollars ($), protons could be cost-effective for ≤ 60-year-old patients with diabetes and ≤50-year-old patients with grade II–III hypertension at the WTP of China ($37,653/QALY); for ≤ 60-year-old patients with diabetes and ≤ 50-year-old patients with grade II–III hypertension or ≥ 2 major cardiac risk factors at a WTP of $50,000/QALY; and for ≤ 60-year-old patients with diabetes, grade II–III hypertension or ≥ 2 major cardiac risk factors and ≤ 50-year-old patients with total cholesterol ≥ 240 mg/dL at a WTP of $100,000/QALY.

Conclusion

Patients' preexisting cardiac risk status was a key factor affecting the cardiac benefits gained from protons and should therefore be a major consideration for the clinical decision of using protons; cost-effective scenarios of protons exist in those patients with high risk of developing cardiac diseases.

Curative intent Stereotactic Ablative Radiation Therapy (SABR) for treatment of lung oligometastases from head and neck squamous cell carcinoma (HNSCC): a multi-institutional retrospective study

OBJECTIVES

The aim of this retrospective study was to assess outcomes of SABR for metachronous isolated lung oligometastases from HNSCC.

METHODS

For patients who developed isolated, 1 or 2 lungs lesions (<5cm) consistent with metastases from HNSCC, the indication of SABR was validated in a multidisciplinary tumor board. All patients were monitored by CT or PET CT after SABR (Stereotactic Ablative Body Radiation) for HNSCC.

RESULTS

Between November 2007 and February 2018, 52 patients were treated with SABR for metachronous lung metastases. The median time from the treatment of the primary HNSCC to the development of lung metastases was 18 months (3-93). The cohort's median age was 65.5 years old (50-83). The vast majority (94.2%) received 60 Gy in three fractions. Forty-one patients (78.5%) presented a solitary lung metastasis, while 11 patients (21.5%) had two lung metastases. With a median follow-up of 45.3 months, crude local and metastatic control rates were 74 and 38%, respectively. 1 year and 2 year Overall Survival (OS) were 85.8 and 65.9%, respectively. The median OS was 46.8 months. About one-fourth of patients were retreated by SABR for distant pulmonary recurrence. The treatment was well tolerated with only one patient who reported ≥ grade 3 toxicity (1.9%).

CONCLUSION

In selected metastatic HNSCC patients, early detection and treatment of lung metastases with SABR is effective and safe. Prospective studies are required to validate this potential shift.

ADVANCES IN KNOWLEDGE

Patients with oligometastases and controlled primary HNSCC seem to benefit from metastasis directed therapies.

Intensity-modulated proton radiation therapy as a radical treatment modality for nasopharyngeal carcinoma in China: A cost-effectiveness analysis

BACKGROUND

Compared to conventional intensity-modulated photon radiation therapy (IMRT), intensity-modulated proton radiation therapy (IMPT) has potential to reduce irradiation-induced late toxicities while maintaining excellent tumor control in patients with nasopharyngeal carcinoma (NPC). However, the relevant cost-effectiveness remains controversial.

METHODS

A Markov decision tree analysis was performed under the assumption that IMPT offered normal tissue complication probability reduction (NTCP reduction) in long-term dysphagia, xerostomia, and hearing loss, compared to IMRT. Base-case evaluation was performed on T2N2M0 NPC of median age (43 years old). A Chinese societal willingness-to-pay threshold (33558 US dollars [$])/quality-adjusted life-year [QALY]) was adopted.

RESULTS

For patients at median age and having NTCP reduction of 10%, 20%, 30%, 40%, 50%, and 60%, their incremental cost-effectiveness ratios were $102684.0/QALY, $43161.2/QALY, $24134.7/QALY, $13991.6/QALY, $8259.8/QALY, and $4436.1/QALY, respectively; IMPT should provide an NTCP reduction of ≥24% to be considered cost-effective.

CONCLUSIONS

IMPT has potential to be cost-effective for average Chinese NPC patients and should be validated clinically.

Metachronous second primary neoplasia in oropharyngeal cancer patients: Impact of tumor HPV status. A GETTEC multicentric study

INTRODUCTION

Patients with oropharyngeal squamous cell carcinoma (OPSCC) display a significant risk to develop a metachronous second primary neoplasia (MSPN). HPV and non-HPV-related OPSCC are 2 distinct entities with biological, clinical and prognostic differences. The aims of our study were to analyze the impact of tumor HPV status and other relevant clinical factors, such as tobacco and/or alcohol (T/A) consumption, on the risk and distribution of MSPN in OPSCC patients and to assess the impact of MSPN on patient survival.

MATERIAL AND METHODS

All OPSCC patients treated from 2009 to 2014 were included in this multicentric retrospective study. P16 immunohistochemical expression was used as a surrogate maker of tumor HPV status. The impact of tumor p16 status on the risk of MSPN was assessed in uni- and multivariate analyses. Overall survival (OS) was determined by Kaplan-Meier analysis.

RESULTS

Among the 1291 patients included in this study, 138 (10.7%) displayed a MSPN which was preferentially located in the head and neck area (H&N), lung and esophagus. Multivariate analyses showed that p16- tumor status (p = 0.003), T/A consumption (p = 0.005) and soft palate tumor site (p = 0.009) were significantly associated with a higher risk of MSPN. We found no impact of p16 tumor status on the median time between index OPSCC diagnosis and MSPN development, but a higher proportion of MSPN arising outside the H&N, lung and esophagus was found in p16 + than in p16- patients. MSPN development had an unfavorable impact (p = 0.04) on OS only in the p16 + patient group.

CONCLUSION

P16 tumor status and T/A consumption were the main predictive factors of MSPN in OPSCC patients. This study provides crucial results with a view to tailoring global management and follow-up of OPSCC patients.

Optimizing oropharyngeal cancer management by using proton beam therapy: trends of cost-effectiveness

Background

Proton beam therapy (PBT) is a new-emerging cancer treatment in China but its treatment costs are high and not yet covered by Chinese public medical insurance. The advanced form of PBT, intensity-modulated proton radiation therapy (IMPT), has been confirmed to reduce normal tissue complication probability (NTCP) as compared to conventional intensity-modulated photon-radiation therapy (IMRT) in patients with oropharyngeal cancer (OPC). Herein, we evaluated the cost-effectiveness and applicability of IMPT versus IMRT for OPC patients in China, aiming at guiding the proper use of PBT.

Methods

A 7-state Markov model was designed for analysis. Base-case evaluation was performed on a 56-year-old (median age of OPC in China) patient under the assumption that IMPT could provide a 25% NTCP-reduction in long-term symptomatic dysphagia and xerostomia. Model robustness was examined using probabilistic sensitivity analysis, cohort analysis, and tornado diagram. One-way sensitivity analyses were conducted to identify the cost-effective scenarios. IMPT was considered as cost-effective if the incremental cost-effectiveness ratio (ICER) was below the societal willingness-to-pay (WTP) threshold.

Results

Compared with IMRT, IMPT provided an extra 0.205 quality-adjusted life-year (QALY) at an additional cost of 34,926.6 US dollars ($), and had an ICER of $170,082.4/ QALY for the base case. At the current WTP of China ($33,558 / QALY) and a current IMPT treatment costs of $50,000, IMPT should provide a minimum NTCP-reduction of 47.5, 50.8, 55.6, 63.3 and 77.2% to be considered cost-effective for patient age levels of 10, 20, 30, 40 and 50-year-old, respectively. For patients at the median age level, reducing the current IMPT costs ($50,000) to a $30,000 level would make the minimum NTCP-reduction threshold for “cost-effective” decrease from 91.4 to 44.6%, at the current WTP of China (from 69.0 to 33.5%, at a WTP of $50,000 / QALY; and from 39.7 to 19.1%, at a WTP of $100,000 / QALY).

Conclusions

Cost-effective scenarios of PBT exist in Chinese OPC patients at the current WTP of China. Considering a potential upcoming increase in PBT use in China, such cost-effective scenarios may further expand if a decrease of proton treatment costs occurs or an increase of WTP level.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08638-2.

Interim analysis of IMMUNEBOOST-HPV: A multicenter, randomized, open label, phase II study evaluating the feasibility, and tolerance of neoadjuvant nivolumab in high-risk HPV driven oropharynx cancer

6037

Background: Among HPV-positive Oropharyngeal Cancer (OPC) patients (pts), some has a less favorable prognosis (T4, N2/N3, smokers >10 pack-year [p/y]). We assume that neoadjuvant immunotherapy might improve their oncological outcomes, so we tested nivolumab (N) prior to ChemoRadiaTion (CRT). Methods: The study population is restricted to HPV positive OPC pts (both p16+ & HPV-DNA+) with advanced disease (T4, N2/N3) or a smoking history >10 p/y. Pts were randomly allocated 1:2 to receive either cisplatin-based CRT (n=20) or 2 cycles of N 240 mg followed by CRT (n=41). The Primary Endpoint (PE) is the rate of pts who can receive Full Treatment in Due Time (FTDT), according to these criteria: a) 2 N infusions on day 1 and on day 14-16 b) CRT started between days 28-37 after the 1st N infusion c) No RT break ≥1 week d) RT dose received >95% of theoretical dose e) Cisplatin dose received ≥200 mg/m² To achieve FTDT, all criteria are required in the Experimental Arm (EA) while only criteria c), d), and e) are required in the Control Arm (CA). In the EA, the trial was designed in 2 steps, with FTDT rate of 88% considered as inacceptable versus an alternative of 98%, a type I error of 0.10, and a type 2 error of 0.08. As per protocol, patient accrual was temporarily suspended after inclusion of 19 pts in the EA (1st step) and results were reviewed by an Independent Data Monitoring Committee (IDMC). To resume pts’ inclusion, FTDT had to be achieved in 18 pts in the EA. Results: From 07/2019 to 09/2020, 30 pts were enrolled including 11 in the CA (demographics are summarized in table). 2 pts in the EA did not reach the PE. For the 1st patient, the cisplatin dose was <200 mg/m2 due to grade 1 hearing loss and grade 2 tinnitus (1st cycle: 100 mg/m2, 2nd cycle: 80 mg/m2, no 3rd cycle). For the 2nd patient, CRT began at D38 due to logistical issues (maintenance of RT devices). As this delay was unrelated to N or to patient's condition, the IDMC considered that the inclusions could resume for the 2nd step. 7 N-related Adverse Events (AE) were reported in 4 pts including 3 serious AE (ankylosing spondylitis flare-up, colitis, diabetic ketoacidosis). Conclusions: Neoadjuvant N before CRT seems feasible for the treatment of OPC pts. The trial has reopened to inclusion as recommended by the IDMC. Clinical trial information: NCT03838263. [Table: see text]

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.

Long-term functional and quality of life outcomes in laryngectomized patients after successful voice restoration using tracheoesophageal prostheses

OBJECTIVE

To assess long-term functional and quality of life (QoL) outcomes and their predictive factors in laryngectomized patients after successful voice restoration using tracheoesophageal prostheses (TEP).

METHODS

This cross-sectional study was conducted in alive and disease-free patients at least 1 year after total laryngectomy ± partial pharyngectomy. Patients completed the European Organization for Research and Treatment of Cancer (EORTC) Core (QLQ-C30) and Head and Neck Cancer (QLQ-H&N35) QoL questionnaires, the Voice Handicap Index (VHI-10) questionnaire and the Hospital Anxiety and Depression Scale (HADS). The level of dysphagia was evaluated using the Dysphagia Handicap Index (DHI) and the Dysphagia Outcomes and Severity Scale (DOSS). Predictive factors of these clinical outcomes were determined in univariate and multivariate analysis.

RESULTS

A total of 48 patients were included in this study. Long-term QoL and functioning scales scores were all superior to 70%. Main persistent symptoms were fatigue, dyspnea, senses, speech and coughing problems. A DOSS score ≥6, indicating normal/subnormal swallowing function, and a VHI-10 score ≤20, representing light to medium voice disorders, were found in at least 75% of patients. An anxiodepressive disorder (HADS global score ≥ 15) was reported by 15 (31%) patients and represented the main predictor of QoL and voice outcomes. A strong correlation was found between VHI-10 and global QoL scores.

CONCLUSIONS

After successful voice restoration, laryngectomized patients achieved satisfactory QoL and functional outcomes. Psychological distress was the main determinant of long-term QoL and is therefore of critical importance in the multidisciplinary management of laryngectomized patients.

Early Toxicities After High Dose Rate Proton Therapy in Cancer Treatments

Background

The conventional dose rate of radiation therapy is 0.01–0.05 Gy per second. According to preclinical studies, an increased dose rate may offer similar anti-tumoral effect while dramatically improving normal tissue protection. This study aims at evaluating the early toxicities for patients irradiated with high dose rate pulsed proton therapy (PT).

Materials and Methods

A single institution retrospective chart review was performed for patients treated with high dose rate (10 Gy per second) pulsed proton therapy, from September 2016 to April 2020. This included both benign and malignant tumors with ≥3 months follow-up, evaluated for acute (≤2 months) and subacute (>2 months) toxicity after the completion of PT.

Results

There were 127 patients identified, with a median follow up of 14.8 months (3–42.9 months). The median age was 55 years (1.6–89). The cohort most commonly consisted of benign disease (55.1%), cranial targets (95.1%), and were treated with surgery prior to PT (56.7%). There was a median total PT dose of 56 Gy (30–74 Gy), dose per fraction of 2 Gy (1–3 Gy), and CTV size of 47.6 ml (5.6–2,106.1 ml). Maximum acute grade ≥2 toxicity were observed in 49 (38.6%) patients, of which 8 (6.3%) experienced grade 3 toxicity. No acute grade 4 or 5 toxicity was observed. Maximum subacute grade 2, 3, and 4 toxicity were discovered in 25 (19.7%), 12 (9.4%), and 1 (0.8%) patient(s), respectively.

Conclusion

In this cohort, utilizing high dose rate proton therapy (10 Gy per second) did not result in a major decrease in acute and subacute toxicity. Longer follow-up and comparative studies with conventional dose rate are required to evaluate whether this approach offers a toxicity benefit.

Upfront surgery or definitive radiotherapy for p16+ oropharyngeal cancer. A GETTEC multicentric study

BACKGROUND

The aim of this study was to assess the impact of the initial therapeutic strategy on oncologic outcomes in patients with HPV-positive OPSCC.

METHODS

All p16-positive OPSCCs treated from 2009 to 2014 in 7 centers were retrospectively included and classified according to the therapeutic strategy: surgical strategy (surgery ± adjuvant radiotherapy and chemotherapy) vs. non-surgical strategy (definitive radiotherapy ± chemotherapy). Univariate, multivariate propensity score matching analyses were performed to compare overall (OS), disease-specific (DSS) and recurrence-free survival (RFS).

RESULTS

382 patients were included (surgical group: 144; non-surgical group: 238). Five-year OS, DSS and RFS were 89.2, 96.8 and 83.9% in the surgical group and 84.2, 87.1 and 70.4% in the non-surgical group, respectively. These differences were statistically significant for DSS and RFS after multivariate analysis, but only for RFS after propensity score matching analysis.

CONCLUSION

In p16+ OPSCC patients, upfront surgery results in higher RFS than definitive radiotherapy ± chemotherapy but does not impact OS.

Oropharyngeal cancer: First relapse description and prognostic factor of salvage treatment according to p16 status, a GETTEC multicentric study

INTRODUCTION

Although Human Papilloma Virus (HPV)-driven oropharyngeal cancer (OPC) prognosis is significantly better than that of other head and neck cancers, up to 25% of cases will recur within 5 years. Data on the pattern of disease recurrence and efficiency of salvage treatment are still sparse.

MATERIAL AND METHOD

Observational study of all recurrent OPCs diagnosed, following a curative intent treatment, in seven French centers from 2009 to 2014. p16 Immunohistochemistry was used to determine HPV status. Clinical characteristics, distribution of recurrence site, and treatment modalities were compared by HPV tumor status. Overall survival was examined using Kaplan-Meier and multivariate Cox regression modeling.

RESULTS

350 recurrent OPC patients (246 p16-negative and 104 p16-positive patients). The site of recurrence was more frequently locoregional for p16-negative patients (65.4% versus 52.9% in p16-positive patients) and metastatic for p16-positive patients (47.1% versus 34.6% in p16-patients, p = 0.03). Time from diagnosis to recurrence did not differ between p16-positive and p16-negative patients (12 and 9.6 months, respectively, p-value = 0.2), as the main site of distant metastasis (all p-values ≥0.10). Overall and relapse-free survival following the first recurrence did not differ according to p16 status (p-values from log-rank 0.30 and 0.40, respectively). In multivariate analysis, prognosis factors for overall survival in p16-negative patients were distant metastasis (HR 2.11, 95% CI 1.30-3.43) and concurrent local and regional recurrences (HR 2.20, 95% CI 1.24-3.88).

CONCLUSION

With the exception of the initial site of recurrence, the pattern of disease relapse and the efficiency of salvage treatment are not different between p16-positive and negative OPCs.

Synchronous primary neoplasia in patients with oropharyngeal cancer: Impact of tumor HPV status. A GETTEC multicentric study

INTRODUCTION

Patients with oropharyngeal squamous cell carcinoma (OPSCC) display a significant risk of synchronous primary neoplasia (SPN) which could impact their management. The aims of this study were to evaluate the risk and distribution of SPN in OPSCC patients according to their HPV (p16) status, the predictive factors of SPN and the impact of SPN on therapeutic strategy and oncologic outcomes.

MATERIAL AND METHODS

All OPSCC patients treated from 2009 to 2014 were included in this multicentric retrospective study. Univariate analyses were conducted using Chi-2 and Fisher exact tests. For multivariate analyses, all variables associated with a p ≤ 0.10 in univariate analysis were included in logistic regression models.

RESULTS

Among the 1291 patients included in this study, 75 (5.8%) displayed a SPN which was preferentially located in the upper aerodigestive tract, lung and esophagus. Comorbidity level (p = 0.03), alcohol (p = 0.005) and tobacco (p = 0.01) consumptions, and p16 tumor status (p < 0.0001) were significant predictors of SPN. In multivariate analysis, p16+ status was significantly associated with a lower risk of SPN (OR = 0.251, IC95% [0.133;0.474]). Patients with a SPN were more frequently referred for non-curative treatment (p = 0.02). In patients treated with curative intent, there was no impact of SPN on the therapeutic strategy (surgical vs. non-surgical treatment). We observed no overall survival differences between patients with or without SPN.

CONCLUSION

P16 tumor status is the main predictive factor of SPN in OPSCC patients. This study provides crucial results which should help adapt the initial work-up and the global management of OPSCC patients.

Upfront surgery or definitive radiotherapy for patients with p16-negative oropharyngeal squamous cell carcinoma. A GETTEC multicentric study

INTRODUCTION

Therapeutic management of oropharyngeal squamous cell carcinomas (OPSCC) is still debated. Since the role of HPV was demonstrated, few studies have focused on HPV-negative OPSCC. The aim of our study was to assess the impact of therapeutic strategy (surgical vs. non-surgical) on oncologic outcomes in patients with HPV-negative OPSCC.

MATERIAL AND METHOD

All p16-negative OPSCCs treated from 2009 to 2014 in 7 tertiary-care centers were included in this retrospective study and were classified according to the therapeutic strategy: surgical strategy (surgery ± adjuvant radiotherapy and chemotherapy) vs. non-surgical strategy (definitive radiotherapy ± chemotherapy). Patients not eligible for surgery (unresectable tumor, poor general-health status) were excluded. Univariate, multivariate and propensity score matching analyses were performed to compare overall (OS), disease-specific (DSS) and recurrence-free survival (RFS).

RESULTS

Four hundred seventy-four (474) patients were included in the study (surgical group: 196; non-surgical group: 278). Five-year OS, DSS and RFS were 76.5, 81.3 and 61.3%, respectively, in the surgical group and 49.9, 61.8 and 43.4%, respectively, in the non-surgical group. The favorable impact of primary surgical treatment on oncologic outcomes was statistically significant after multivariate analysis. This effect was more marked for locally-advanced than for early-stage tumors. Propensity score matching analysis confirmed the prognostic impact of primary surgical treatment for RFS.

CONCLUSION

Therapeutic strategy is an independent prognostic factor in patients with p16-negative OPSCC and primary surgical treatment is associated with improved OS, DSS and RFS. These results suggest that surgical strategy is a reliable option for advanced stage OPSCC.

Clinical response assessment after contact X-Ray brachytherapy and chemoradiotherapy for organ preservation in rectal cancer T2-T3 M0: The time/dose factor influence

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Treatment initiation of T2-T3 rectal cancers with Contact (CXB) provides a fast clinical complete response.

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In T2N0< 3 cm tumors, CXB first with chemoradiotherapy can achieve local control in more than 85%.

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The Phase III OPERA trial should bring robust data in favor of CXB as initial treatment of T2N0< 3 cm.

Introduction

A neoadjuvant treatment aimed at rectal preservation should achieve a clinical complete response. This study comparing neoadjuvant treatment initiated with Contact X-ray (CXB) or External Beam radiotherapy (EBRT) is evaluating the influence of the time/dose parameter on clinical response during the first six months.

Materials and methods

This retrospective consecutive series included T2-3 rectal adenocarcinoma staged using digital examination (DRE), endoscopy, magnetic radiation imaging and/or endorectal ultrasound. All patients were treated with organ preservation intent. Treatment protocol combined CXB (80–110 Gy/3–4 fractions) and EBRT ± concurrent capecitabine. In tumor exceeding 3.5 cm treatment was often initiated using EBRT. Clinical response was assessed (DRE, proctoscopy ± imaging) at very close interval between 2 weeks and 6 months after treatment initiation.

Results

Between 2002 and 2017, 61 patients (T2: 31; T3: 30) M0 (median age: 76 years) were treated. Treatment was initiated in 40 patients (T2: 28, T3: 12) with contact X-ray and in 21 (T2: 4, T3: 17) with EBRT. Using contact X-ray or EBRT first treatment, clinical complete (or near complete) response at week 14(±1) was respectively 88% [95CI:74–96] and 33% [95CI:15–57]. In multivariate analysis the treatment chronology was the most significant factor influencing cCR (OR: 7.53). At 6 months, with contact X-ray first all patients were in clinical complete response and five with EBRT remained in partial response. With 61 months median follow-up time, the local recurrence rate was 10% [95% CI: 6–16] at 5 years. T3 and fungating tumors were at higher risk of local recurrence. Organ preservation with good function was achieved in 95% of cases.

Conclusion

This non randomized study tends to show that in early T2-3 tumors, a strategy using upfront contact therapy, which is reducing the overall treatment time, is an option allowing a more favorable outcome than EBRT first.

Stereotactic Pelvic Reirradiation for Locoregional Cancer Relapse

AIMS

Up to 40% of patients who have received radiation for a pelvic malignancy will develop locoregional recurrence in the previously irradiated volume. Stereotactic body radiotherapy (SBRT) has been used in the oligometastatic setting, and provides an ablative approach ideal for reirradiation. The purpose of this study was to evaluate the outcomes after SBRT reirradiation of extraosseous recurrences in the pelvis.

MATERIALS AND METHODS

This single institution retrospective study evaluated patients treated with SBRT reirradiation in the pelvis from January 2011 to February 2018. Patients with more than five oligometastatic lesions, >7 cm in size, and recurrence within the prostate were excluded.

RESULTS

In total, 30 patients were treated with SBRT with a median follow-up of 29.4 months. The primary tumour sites were most commonly rectum (30.8%) and prostate (30.8%). The median time interval between irradiation for the primary and SBRT reirradiation was 48 months (3-245). The typical reirradiation treatment was 35 Gy in five fractions, the median gross tumour volume size was 10.2 (0.3-110.5) ml and the most common target was the iliac nodes (40%). There were three (10%) acute grade 3 toxicities and no late grade 3 or more toxicities. At 12/24 months, local relapse-free survival, metastasis-free survival, progression-free survival and overall survival were 67.7%/50.7%, 67%/41.7%, 34.8%/14.9% and 83.2%/62.5%, respectively. On univariate analysis, improved local control was associated with low gross tumour volume (<10 ml) (P = 0.003) and prostate primary (P = 0.02), but was no longer significant on multivariate analysis. The proximity of organ at risk to the target did not significantly correlate with worse toxicity (P = 0.14) or tumour coverage (gross tumour volume: P = 0.8, planning target volume: P = 0.4).

CONCLUSION

SBRT pelvic reirradiation in oligometastatic patients is a safe and effective treatment modality. Careful consideration should be taken with larger tumour size, as it may be associated with worse oncological and toxicity outcome.

Cost-effectiveness analysis of proton beam therapy for treatment decision making in paranasal sinus and nasal cavity cancers in China

Background

Cost-effectiveness is a pivotal consideration for clinical decision making of high-tech cancer treatment in developing countries. Intensity-modulated proton radiation therapy (IMPT, the advanced form of proton beam therapy) has been found to improve the prognosis of the patients with paranasal sinus and nasal cavity cancers compared with intensity-modulated photon-radiation therapy (IMRT). However, the cost-effectiveness of IMPT has not yet been fully evaluated. This study aimed at evaluating the cost-effectiveness of IMPT versus IMRT for treatment decision making of paranasal sinus and nasal cavity cancers in Chinese settings.

Methods

A 3-state Markov model was designed for cost-effectiveness analysis. A base case evaluation was performed on a patient of 47-year-old (median age of patients with paranasal sinus and nasal cavity cancers in China). Model robustness was examined by probabilistic sensitivity analysis, Markov cohort analysis and Tornado diagram. Cost-effective scenarios of IMPT were further identified by one-way sensitivity analyses and stratified analyses were performed for different age levels. The outcome measure of the model was the incremental cost-effectiveness ratio (ICER). A strategy was defined as cost-effective if the ICER was below the societal willingness-to-pay (WTP) threshold of China (30,828 US dollars ($) / quality-adjusted life year (QALY)).

Results

IMPT was identified as being cost-effective for the base case at the WTP of China, providing an extra 1.65 QALYs at an additional cost of $38,928.7 compared with IMRT, and had an ICER of $23,611.2 / QALY. Of note, cost-effective scenarios of IMPT only existed in the following independent conditions: probability of IMPT eradicating cancer ≥0.867; probability of IMRT eradicating cancer ≤0.764; or cost of IMPT ≤ $52,163.9. Stratified analyses for different age levels demonstrated that IMPT was more cost-effective in younger patients than older patients, and was cost-effective only in patients ≤56-year-old.

Conclusions

Despite initially regarded as bearing high treatment cost, IMPT could still be cost-effective for patients with paranasal sinus and nasal cavity cancers in China. The tumor control superiority of IMPT over IMRT and the patient’s age should be the principal considerations for clinical decision of prescribing this new irradiation technique.

A brief history of contact X-ray brachytherapy 50 kVp

Contact X ray brachytherapy 50 kVp was initiated in the 1930s with the Siemens unit and popularized with the Philips unit in the 1950s. A renaissance was seen in the early 2000s with the Intrabeam™ unit for breast IORT. Presently the Papillon™ systems thanks to its high dose rate (>10Gy/mn) can be used to treat breast (IORT), skin, eyelid and rectal cancers. Future developments are expected to consolidate the place of contact radiotherapy as a safe and efficient treatment for accessible early tumors.

Mitomycin and 5-fluorouracil for second-line treatment of metastatic squamous cell carcinomas of the anal canal

Background

Metastatic squamous cell carcinomas (SCC) of the anal canal are rare and there is no international consensus on their second‐line management. 5‐Fluorouracil (5‐FU) and mitomycin in combination with radiotherapy is the standard for locally advanced forms but its efficacy in metastatic stage has never been evaluated.

Patients and methods

We report a retrospective analysis of patients treated with 5‐FU and mitomycin from 2000 to 2017 in our institution for a metastatic SCC of the anal canal after failure of platinum‐based regimen. The main outcome was progression‐free survival (PFS) and the secondary outcomes were overall survival (OS), response rate, and toxicity.

Results

Nineteen patients, 15 women and four men, with a median age of 57 years were identified (range, 40‐79 years). Patients received a median of three cycles (1‐7) of mitomycin 5‐FU. A dose reduction was necessary in six patients (31.6%), one patient had to discontinue treatment following toxicity and no death was due to treatment toxicity was reported. An objective response was observed in five patients (26.4%, 95% CI 6.6‐46.2) including one complete response, six patients (31.6%, 95% CI 10.7‐52.5) showed tumor stabilization. Median PFS and OS were 3 months [95% CI 1‐5] and 7 months [95% CI 2.2‐11.8]. Responder had a median duration of response of 4 months [95% CI 1.8‐6.1] and one patient had 23 months duration of response. No significant difference was noted for PFS and OS for patients previously treated with mitomycin and 5‐FU at a local stage.

Conclusion

Mitomycin and 5‐FU regimen provides tumor control with acceptable tolerance. It is an option for patients with metastatic SCC of the anal canal after failure of platinum‐based chemotherapy. [Correction added on 9 October 2019, after first online publication: '5‐FU' was inadvertently removed from the Results and Conclusion and has now been added to the text.]

Evolution and predictive factors of quality of life in patients undergoing oncologic surgery for head and neck cancer: A prospective multicentric study

OBJECTIVES

The purposes of this study were to assess the evolution of quality of life (QoL) in patients with head and neck squamous cell carcinoma (HNSCC) undergoing oncologic surgery and to determine the predictive factors of post-therapeutic QoL.

METHODS

All HNSCC patients who underwent primary surgery, between 2012 and 2014, were enrolled in this prospective multicentric study. Patients completed the EORTC QLQ-C30 and QLQ-H&N35 questionnaires before surgery and at 6 months after treatment. Predictive factors of post-therapeutic QoL scores were determined.

RESULTS

A total of 200 patients were included in this study. There was no significant deterioration of global QoL and no significant increase in general symptoms between the pre- and post-therapeutic periods, but a significant deterioration in role and social functioning, and an increase of most head and neck symptoms. Tumor stage, tumor site and treatment modalities (type of surgery, adjuvant therapy) were the main predictors of QoL scores. We found a negative correlation between satisfaction with the information received and global QoL score or several functioning scales.

CONCLUSION

HNSCC surgical treatment affects patients QoL mainly by increasing head and neck symptoms, which results in social and role functioning deterioration. These results are of great interest to improve multidisciplinary care of HNSCC patients.

Impact of HPV-associated p16-expression and other clinical factors on therapeutic decision-making in patients with oropharyngeal cancer: A GETTEC multicentric study

OBJECTIVES

To analyze the impact of tumor p16 status and other clinical factors on the therapeutic decision-making process in patients with oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

We conducted a multicenter retrospective study (GETTEC collaborative study group) enrolling all OPSCC patients with a determined p16-status considered eligible for surgery between 2009 and 2014. The impact of p16-status and other clinical factors on the therapeutic decision was evaluated in multivariate analysis.

RESULTS

A total of 476 patients were enrolled in the study, including 244 cases (51%) of p16-positive OPSCC. Overall, 223 (47%) patients underwent primary surgery, and 184 (83%) of them received postoperative radiotherapy ± chemotherapy. More patients with p16-positive OPSCC tended to undergo non-surgical treatment than did patients with p16-negative OPSCC (p = 0.10). Multivariate analysis showed that 5 factors significantly influenced therapeutic management of the patients: T-stage ≥ 3 (towards a non-surgical strategy; p < 0.001), N-stage ≥ 2a (non-surgical strategy; p = 0.02), tumor involvement of the glosso-tonsillar sulcus (surgical strategy; p = 0.002), tumor extension to the oral cavity (surgical strategy; p < 0.009) and the center of care (p < 0.001). The rate of patients directed towards a surgical strategy varied between 9% and 74% depending on the center.

CONCLUSION

There was a non-significant trend to recommend patients with p16-positive OPSCC for non-surgical treatment. Center of care, tumor stage and tumor anatomical subsite and extensions were the main determinants of the treatment choice.

Long-term quality of life and psycho-social outcomes after oropharyngeal cancer surgery and radial forearm free-flap reconstruction: A GETTEC prospective multicentric study

OBJECTIVE

To assess long-term quality of life (QoL) and psycho-social outcomes, and to determine their predictive factors after oropharyngeal cancer (OPC) surgery and radial forearm free-flap (RFFF) reconstruction.

METHODS

Patients who had undergone OPC surgery and RFFF reconstruction who were still alive and disease-free at least 1 year after surgery were enrolled in this prospective multicentric study. Patients completed the European Organization for Research and Treatment of Cancer (EORTC) Core (QLQ-C30) and Head and Neck Cancer (QLQ-H&N35) QoL questionnaires, the Voice Handicap Index (VHI-10) questionnaire and the Hospital Anxiety and Depression Scale (HADS). The level of dysphagia was evaluated using the Dysphagia Handicap Index (DHI) and the Dysphagia Outcomes and Severity Scale (DOSS). Predictive factors of these clinical outcomes were determined in univariate and multivariate analysis.

RESULTS

A total of 58 patients were included in this study. Long-term QoL and functioning scales scores were well-preserved (all superior to 70%). Main persistent symptoms were fatigue, reduced sexuality and oral function-related disorders (swallowing, teeth, salivary and mouth-opening problems). HADS anxiety and depression scores were 7.2 and 5.4, respectively. Twenty-one (36%) patients presented an anxiodepressive disorder (HADS global score ≥ 15). Among the 21 patients who were still working before surgery, 11 (52%) had returned to work at the time of our study. The HADS global score (p < 0.001) was the main predictor of QoL, VHI-10 and DOSS scores.

CONCLUSIONS

Psychological distress is the main determinant of long-term QoL and is therefore of critical importance in the multidisciplinary management of OPC patients.

Exclusive chemoradiotherapy with or without dose escalation in locally advanced esophageal carcinoma: The CONCORDE study (PRODIGE 26)

4037

Background: In esophageal cancer (EC), 20 to 45% of patients suffer from local failure after 50Gy concomitant chemoradiation (cCRT). Improvements in staging together with target definitions led us to test dose escalation in the modern era of new technologies. Methods: Patients were randomly assigned cCRT to 40Gy elective nodal irradiation with either a 10Gy boost (Arm A) or 26Gy boost (Arm B) combined with FOLFOX-4. The primary endpoint of this phase II was acute toxicity according to the NCIC-CTCAE (version 4.0). Quality of life according to the EORTC QLQ-C30 and OG25 was a secondary endpoint. All analyses were performed in intent-to-treat. Results: 160 patients were randomized between Jun 2011 and Feb 2016: 81 patients in arm A and 79 patients in arm B. The mean age at diagnosis was 61.9 (7.9) years and 62.1 (7.8) years, respectively. Seventy patients in each arm had squamous cell carcinoma (86.4% in arm A and 88.6% in arm B) and 59 patients (72.8%) and 58 patients (73.4%) had stage III disease in arms A and B, respectively. IMRT was performed in 57 (70.4%) and 55 (69.6%) patients in arms A and B. The rates of grade ≥3 (G3+) non-hematological toxicity were not significantly different between arms A and B (76.5% vs 86.0%, p = 0.12). The rates of G3+ hematological toxicity were not significantly different between arms A and B (82.7% vs 88.6%, p = 0.29). The rates of G3+ non-hematological toxicity were not significantly different between patients treated with 3DRT (83.3%) and IMRT (81.3%) (p = 0.77). The mean global health scores at baseline and 3 months were 63.9 (sd = 21.4) vs 69.6 (sd = 23.1) in arm A (p = 0.10) and 65.27 (sd = 19.54) vs 58.8 (sd = 19.9) in arm B (p = 0.16). The presence of dysphagia was neither significantly different between arm A (89.23%) and arm B (86.21%) (p = 0.61) at baseline nor at 3 months (77.78% vs 86.84%, p = 0.29). Odynophagia was present at baseline in 78.46% in arm A and 75.86% in arm B (p = 0.73) while the rates observed at 3 months were 68.18% and 73.68%, respectively (p = 0.59). Conclusions: Dose escalated cCRT in patients with EC is feasible with no increased acute toxicity and no deterioration of QOL. A phase III trial is on-going to conclusively address the issue of local control with cCRT. Clinical trial information: NCT01348217.

[Indications and results for protontherapy in cancer treatments]

Purpose was to summarize results for proton therapy in cancer treatment. A systematic review has been done by selecting studies on the website www.pubmed.com (Medline) and using the following keywords: proton therapy, radiation therapy, cancer, chordoma, chondrosarcoma, uveal melanoma, retinoblastoma, meningioma, glioma, neurinoma, pituitary adenoma, medulloblastoma, ependymoma, craniopharyngioma and nasal cavity. There are several retrospective studies reporting results for proton therapy in cancer treatments in the following indications: ocular tumors, nasal tumors, skull-based tumors, pediatric tumors. There is no prospective study except one phase II trial in medulloblastoma. The use of proton therapy for these indications is due to dosimetric advantages offering better tumor coverage and organ at risk sparing in comparison with photon therapy. Clinical results are historically at least as efficient as photon therapy with a better toxicity profile in pediatric tumors (cognitive and endocrine functions, radiation-induced cancer) and a better tumoral control in tumors of the nasal cavity. Clinical advantages of proton therapy counterbalance its cost especially in pediatric tumors. Proton therapy could be used in other types of cancer. Proton therapy showed good outcome in ocular, nasal tumors, pediatric, skull-based and paraspinal tumors. Because of some dosimetric advantages, proton therapy could be proposed for other indications in cancer treatments.

A Nomogram to predict parotid gland overdose in head and neck IMRT

Purposes

To generate a nomogram to predict parotid gland (PG) overdose and to quantify the dosimetric benefit of weekly replanning based on its findings, in the context of intensity-modulated radiotherapy (IMRT) for locally-advanced head and neck carcinoma (LAHNC).

Material and methods

Twenty LAHNC patients treated with radical IMRT underwent weekly computed tomography (CT) scans during IMRT. The cumulated PG dose was estimated by elastic registration. Early predictors of PG overdose (cumulated minus planned doses) were identified, enabling a nomogram to be generated from a linear regression model. Its performance was evaluated using a leave-one-out method. The benefit of weekly replanning was then estimated for the nomogram-identified PG overdose patients.

Results

Clinical target volume 70 (CTV70) and the mean PG dose calculated from the planning and first weekly CTs were early predictors of PG overdose, enabling a nomogram to be generated. A mean PG overdose of 2.5Gy was calculated for 16 patients, 14 identified by the nomogram. All patients with PG overdoses >1.5Gy were identified. Compared to the cumulated delivered dose, weekly replanning of these 14 targeted patients enabled a 3.3Gy decrease in the mean PG dose.

Conclusion

Based on the planning and first week CTs, our nomogram allowed the identification of all patients with PG overdoses >2.5Gy to be identified, who then benefitted from a final 4Gy decrease in mean PG overdose by means of weekly replanning.