Dose-volume-related dysphagia after constrictor muscles definition in head and neck cancer intensity-modulated radiation treatment

The role of the soft palate dose regarding normal tissue toxicities in older adults with head and neck cancer undergoing definitive radiotherapy

PURPOSE

The number of older adults with head and neck squamous cell carcinoma (HNSCC) is continuously increasing. Older HNSCC patients may be more vulnerable to radiotherapy-related toxicities, so that extrapolation of available normal tissue complication probability (NTCP) models to this population may not be appropriate. Hence, we aimed to investigate the correlation between organ at risk (OAR) doses and chronic toxicities in older patients with HNSCC undergoing definitive radiotherapy.

METHODS

Patients treated with definitive radiotherapy, either alone or with concomitant systemic treatment, between 2009 and 2019 in a large tertiary cancer center were eligible for this analysis. OARs were contoured based on international consensus guidelines, and EQD2 doses using α/ß values of 3 Gy for late effects were calculated based on the radiation treatment plans. Treatment-related toxicities were graded according to Common Terminology Criteria for Adverse Events version 5.0. Logistic regression analyses were carried out, and NTCP models were developed and internally validated using the bootstrapping method.

RESULTS

A total of 180 patients with a median age of 73 years fulfilled the inclusion criteria and were analyzed. Seventy-three patients developed chronic moderate xerostomia (grade 2), 34 moderate dysgeusia (grade 2), and 59 moderate-to-severe (grade 2-3) dysphagia after definitive radiotherapy. The soft palate dose was significantly associated with all analyzed toxicities (xerostomia: OR = 1.028, dysgeusia: OR = 1.022, dysphagia: OR = 1.027) in the multivariable regression. The superior pharyngeal constrictor muscle was also significantly related to chronic dysphagia (OR = 1.030). Consecutively developed and internally validated NTCP models were predictive for the analyzed toxicities (optimism-corrected AUCs after bootstrapping: AUCxerostomia=0.64, AUCdysgeusia=0.60, AUCdysphagia=0.64).

CONCLUSIONS

Our data suggest that the dose to the soft palate is associated with chronic moderate xerostomia, moderate dysgeusia and moderate-to-severe dysphagia in older HNSCC patients undergoing definitive radiotherapy. If validated in external studies, efforts should be undertaken to reduce the soft palate dose in these patients.

Radiation-induced long-term dysphagia in survivors of head and neck cancer and association with dose-volume parameters

BACKGROUND

Although dysphagia is a common side effect after radiotherapy (RT) of head and neck cancer (HNC), data on long-term dysphagia is scarce. We aimed to 1) compare radiation dose parameters in HNC survivors with and without dysphagia, 2) investigate factors associated with long-term dysphagia and its possible impact on health-related quality of life (HRQoL), and 3) investigate how our data agree with existing NTCP models.

METHODS

This cross-sectional study conducted in 2018-2020, included HNC survivors treated in 2007-2013. Participants attended a one-day examination in hospital and filled in patient questionnaires. Dysphagia was measured with the EORTC QLQ-H&N35 swallowing scale. Toxicity was scored with CTCAE v.4. We contoured swallowing organs at risk (SWOAR) on RT plans, calculated dose-volume histograms (DVHs), performed logistic regression analyses and tested our data in established NTCP models.

RESULTS

Of the 239 participants, 75 (31%) reported dysphagia. Compared to survivors without dysphagia, this group had reduced HRQoL and the DVHs for infrahyoid SWOAR were significantly shifted to the right. Long-term dysphagia was associated with age (OR 1.07, 95% CI 1.03-1.10), female sex (OR 2.75, 95% CI 1.45-5.21), and mean dose to middle pharyngeal constrictor muscle (MD-MPCM) (OR 1.06, 95% CI 1.03-1.09). NTCP models overall underestimated the risk of long-term dysphagia.

CONCLUSIONS

Long-term dysphagia was associated with higher age, being female, and high MD-MPCM. Doses to distally located SWOAR seemed to be risk factors. Existing NTCP models do not sufficiently predict long-term dysphagia. Further efforts are needed to reduce the prevalence and consequences of this late effect.

Toxicities and clinical outcome of adjuvant dysphagia optimized versus standard intensity-modulated radiotherapy for post-operative oral cavity cancers: A prospective comparative study

BACKGROUND

We prospectively assessed acute and late toxicity in post-operative oral cavity squamous cell carcinoma (PO-OCSCC) treated with adjuvant dysphagia optimized intensity-modulated radiotherapy (Do-IMRT) versus standard IMRT (S-IMRT).

MATERIAL AND METHODS

Fifty-six patients of PO-SCC without indications of concurrent chemotherapy were alternatively allocated to adjuvant Do-IMRT (n = 28) versus S-IMRT (n = 28) arms. High- and low-risk planning target volume received 60 and 54 Gy, respectively, in 30 fractions over 6 weeks. Dysphagia aspiration-related structures (DARS) were contoured in both arms. While dosimetric constraints were given in Do-IMRT arm, doses to DARS were only observed without dose constraints in S-IMRT arm. Acute and late toxicity were assessed by common terminology criteria for adverse events (CTCAE) v5.0 and RTOG criteria, respectively.

RESULTS

The primary site of disease was buccal mucosa (64% vs. 53%) and oral tongue (21% vs. 32%), in Do-IMRT and S-IMRT, respectively. The mean doses to DARS was significantly less with Do-IMRT (all p < 0.001) as compared to S-IMRT. Median follow-up was 24.2 months. Grade ≥2 oral pain was less in the Do-IMRT arm (50% vs. 78.6%, p = 0.05). Grade ≥2 late dysphagia at 2 years were significantly less in Do-IMRT arm (0% vs. 17.9%, p = 0.016). Two-year locoregional control was 89.2% in Do-IMRT and 78.5% in S-IMRT (p = 0.261).

CONCLUSION

DARS can be spared in PO-OCSCC patients treated with Do-IMRT without compromising coverage of the target volumes. Limiting doses to DARS leads to lesser acute and late toxicity without compromising locoregional control.

Assessment of radio(chemo)therapy-related dysphagia in head and neck cancer patients based on cough-related acoustic features: a prospective phase II national clinical trial (ACCOUGH-P/A trial)

BACKGROUND

Radiation-associated dysphagia is defined as impaired swallowing efficiency/safety following (chemo)radiotherapy in head and neck cancer patients. In a dysphagia framework, impaired coughing may lead to lung aspiration and fatal lung infection. Although cough efficacy is a predictor of the risk of aspiration, cough investigation is minimal in patients with radiation-associated dysphagia. Because cough is a transient signal, existing software for speech analysis are not appropriate. The goal of our project is to develop an assessment method using acoustic features related to voluntary and reflexive coughs as biomarkers of the risk of penetration/aspiration in patients with radiation-associated dysphagia.

METHODS

Healthy subjects and head and neck cancer patients with and without dysphagia will produce voluntary coughs, throat clearings and reflexive coughs. Recordings will be made using an acoustic microphone and a throat microphone. The recorded signals will be manually segmented and subsequently analysed with a software under development. Automatic final segmentation enables to measure cough duration. The first method of analysis includes temporal features: the amplitude contour, the sample entropy and the kurtosis. These features report respectively the strength, the unpredictability (turbulence noise due to the air jet) and the impulsive quality (burst) of the signal. The second method of analysis consists of a spectral decomposition of the relative cough signal energy into several frequency bands (0-400 Hz, 400-800 Hz, 800-1600 Hz, 1600-3200 Hz, > 3200 Hz). The primary outcome of this exploratory research project is the identification of a set of descriptive acoustic cough features in healthy subjects as reference data (ACCOUGH). The secondary outcome of this research in head and neck cancer patients with radiation-associated dysphagia includes the identification of (1) a set of descriptive acoustic cough features as biomarkers of penetration-aspiration (ACCOUGH-P/A), (2) swallowing scores, (3) voice features and (4) aerodynamic cough features.

DISCUSSION

This study is expected to develop methods of acoustic cough analysis to enhance the assessment of radiation-associated dysphagia in head and neck cancer patients following (chemo)radiation.

TRIAL REGISTRATION

International Standard Randomized Controlled Trials Number (ISRCTN) registry ISRCTN16540497. Accepted on 23 June 2023.

Effectiveness of Home-Based Telerehabilitation Interventions for Dysphagia in Patients With Head and Neck Cancer: Systematic Review

BACKGROUND

Multimodal treatment-induced dysphagia has serious negative effects on survivors of head and neck cancer. Owing to advances in communication technologies, several studies have applied telecommunication-based interventions that incorporate swallowing exercises, education, monitoring, feedback, self-management, and communication. It is especially urgent to implement home-based remote rehabilitation in the context of the COVID-19 pandemic. However, the optimal strategy and effectiveness of remote interventions are unclear.

OBJECTIVE

This systematic review aimed to examine the evidence regarding the efficacy of telerehabilitation for reducing physiological and functional impairments related to swallowing and for improving adherence and related influencing factors among head and neck cancer survivors.

METHODS

The PubMed, MEDLINE, CINAHL, Embase, and Cochrane Library databases were systematically searched up to July 2023 to identify relevant articles. In total, 2 investigators independently extracted the data and assessed the methodological quality of the included studies using the quality assessment tool of the Joanna Briggs Institute.

RESULTS

A total of 1465 articles were initially identified; ultimately, 13 (0.89%) were included in the systematic review. The quality assessment indicated that the included studies were of moderate to good quality. The results showed that home-based telerehabilitation improved the safety of swallowing and oral feeding, nutritional status, and swallowing-related quality of life; reduced negative emotions; improved swallowing rehabilitation adherence; was rated by participants as highly satisfactory and supportive; and was cost-effective. In addition, this review investigated factors that influenced the efficacy of telerehabilitation, which included striking a balance among swallowing training strategy, intensity, frequency, duration, and individual motor ability; treating side effects of radiotherapy; providing access to medical, motivational, and educational information; providing feedback on training; providing communication and support from speech pathologists, families, and other survivors; and addressing technical problems.

CONCLUSIONS

Home-based telerehabilitation has shown great potential in reducing the safety risks of swallowing and oral feeding, improving quality of life and adherence, and meeting information needs for dysphagia among survivors of head and neck cancer. However, this review highlights limitations in the current literature, and the current research is in its infancy. In addition, owing to the diversity of patient sociodemographic, medical, physiological and functional swallowing, and behavioral factors, we recommend the development of tailored telemedicine interventions to achieve the best rehabilitation effects with the fewest and most precise interventions.

Toxicity, normal tissue and dose-volume planning parameters for radiotherapy in soft tissue sarcoma of the extremities: A systematic review of the literature

BACKGROUND

Patients with soft tissue sarcoma of the extremities (STSE) are left with high incidence of toxicities after Radiotherapy (RT). Understanding the normal tissue dose relationship with the development of long-term toxicities may enable better RT planning in order to reduce treatment toxicities for STSE. This systematic review of the literature aims at reporting the incidence of acute and late toxicities and identifying RT delineation guidance the normal tissues structures and dose-volume parameters for STSE.

METHODS

A literature search of PUBMED-MEDLINE for studies that reported data on RT toxicity outcomes, delineation guidelines and dose-volume parameters for STSE from 2000 to 2022. Data has been tabulated and reported.

RESULTS

Thirty of 586 papers were selected after exclusion criteria. External beam RT prescriptions ranged from 30 to 72 Gy. The majority of studies reported the use of Intensity Modulated RT (IMRT) (27%). Neo-adjuvant RT was used in 40%. The highest long-term toxicities were subcutaneous and lymphoedema, reported when delivering 3DCRT. IMRT had a lower incidence of toxicities. Normal tissue outlining such as weight-bearing bones, skin and subcutaneous tissue, corridor and neurovascular bundle was recommended in 6 studies. Nine studies recommended the use of dose-volume constraints, but only one recommended evidence-based dose-volume constraints.

CONCLUSION

Although the literature is replete with toxicity reports, there is a lack of evidence-based guidance on normal tissue and dose-volume parameters and strategies to reduce the normal tissues irradiation when optimising RT plans for STSE are poor compared to other tumour sites.

Survival and Swallowing Function after Primary Radiotherapy versus Transoral Robotic Surgery for Human Papillomavirus-Associated Oropharyngeal Squamous Cell Carcinoma

INTRODUCTION

The aim of this study was to investigate the impact of primary transoral robotic surgery (TORS) versus radiotherapy (RT) on progression-free survival (PFS), overall survival (OS), and 1-year swallowing function for patients with early-stage HPV-associated oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Patients with stage I-II (AJCC 8th Ed.) HPV-associated OPSCC treated with TORS followed by risk-adapted adjuvant therapy or (chemo)radiotherapy between 2014 and 2019 were identified. PFS, OS, and swallowing outcomes including gastrostomy tube (GT) use/dependence, and Functional Oral Intake Scale (FOIS) change over 1 year were compared.

RESULTS

One hundred sixty-seven patients were analyzed: 116 treated with TORS with or without adjuvant RT and 51 treated with RT (50 chemoRT). The RT group had more advanced tumor/nodal stage, higher comorbidity, and higher rates of concurrent chemotherapy. There were no differences in 3-year PFS (88% TORS vs. 75% RT) or OS (90% vs. 81%) between groups, which persisted after adjusting for stage, age, and comorbidity. GT use/dependence rates were higher in the RT group. Mean (SD) FOIS scores in the TORS group were 6.9 (0.4) at baseline and 6.4 (1.0) at 1 year, compared with 6.7 (0.6) and 5.6 (1.7) for the RT group. Only clinical nodal stage was found to be significantly associated with FOIS change from baseline to 1 year.

CONCLUSION

There were no differences in PFS or OS between patients treated with primary TORS or RT for early-stage HPV-associated OPSCC. Clinical N2 status is associated with FOIS change at 1 year and may be the major factor affecting long-term swallowing function, irrespective of primary treatment modality.

Medial retropharyngeal nodal region sparing radiotherapy versus standard radiotherapy in patients with nasopharyngeal carcinoma: open label, non-inferiority, multicentre, randomised, phase 3 trial

OBJECTIVES

To address whether sparing the medial retropharyngeal lymph node (MRLN) region from elective irradiation volume provides non-inferior local relapse-free survival versus standard radiotherapy in patients with nasopharyngeal carcinoma.

DESIGN

Open-label, non-inferiority, multicentre, randomised, phase 3 trial.

SETTING

Three Chinese hospitals between 20 November 2017 and 3 December 2018.

PARTICIPANTS

Adults (18-65 years) with newly diagnosed, non-keratinising, non-distant metastatic nasopharyngeal carcinoma without MRLN involvement.

INTERVENTIONS

Randomisation was done centrally by the Clinical Trials Centre at Sun Yat-sen University Cancer Center. Eligible patients were randomly assigned (1:1; block size of four) to receive MRLN sparing radiotherapy or standard radiotherapy (both medial and lateral retropharyngeal lymph node groups), and stratified by institution and treatment modality as follows: radiotherapy alone; concurrent chemoradiotherapy; induction chemotherapy plus radiotherapy or concurrent chemoradiotherapy.

MAIN OUTCOME MEASURES

Non-inferiority was met if the lower limit of the one sided 97.5% confidence interval of the absolute difference in three year local relapse-free survival (MRLN sparing radiotherapy minus standard radiotherapy) was greater than -8%.

RESULTS

568 patients were recruited: 285 in the MRLN sparing radiotherapy group; 283 in the standard radiotherapy group. Median follow-up was 42 months (interquartile range 39-45), intention-to-treat analysis showed that the three year local relapse-free survival of the MRLN sparing radiotherapy group was non-inferior to that of the standard radiotherapy group (95.3% v 95.5%, stratified hazard ratio 1.04 (95% confidence interval 0.51 to 2.12), P=0.95) with a difference of -0.2% ((one sided 97.5% confidence interval -3.6 to ∞), P_{non-inferiority}<0.001). In the safety set (n=564), the sparing group had a lower incidence of grade ≥1 acute dysphagia (25.5% v 35.1%, P=0.01) and late dysphagia (24.0% v 34.3%, P=0.008). Patient reported outcomes at three years after MRLN sparing radiotherapy were better in multiple domains after adjusting for the baseline values: global health status (mean difference -5.6 (95% confidence interval -9.1 to -2.0), P=0.002), role functioning (-5.5 (-7.4 to -3.6), P<0.001), social functioning (-6.2 (-8.9 to -3.6), P<0.001), fatigue (7.9 (4.0 to 11.8), P<0.001), and swallowing (11.0 (8.4 to 13.6), P<0.001). The difference in swallowing scores reached clinical significance (>10 points difference).

CONCLUSION

Compared with standard radiotherapy, MRLN sparing radiotherapy showed non-inferiority in terms of risk of local relapse with fewer radiation related toxicity and improved patient reported outcomes in patients with non-metastatic nasopharyngeal carcinoma.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03346109.

Kyphoplasty of C2 Pathological Fractures Using an Anterior Midline Approach and Steerable Osteotome: Technical Note and Case Series

BACKGROUND

Malignant lesions involving the C2 vertebral body (axis) may be challenging to treat, and not all patients with cancer are good candidates for posterior cervical or occipitocervical instrumentation.

OBJECTIVE

To describe a modified technique of the direct anterolateral C2 kyphoplasty using a steerable osteotome, commonly used for the treatment of thoracolumbar spinal lesions. We also report a case series of 11 patients treated with this technique at our institution.

METHODS

The authors performed a retrospective review of all patients who underwent a C2 kyphoplasty using the anterior midline approach from 2010 to 2020. Patient demographics, tumor characteristics, pain severity (visual analog scale), Karnofsky performance status , perioperative complications, and postoperative spinal stability were assessed.

RESULTS

The main indication for a C2 kyphoplasty was refractory neck pain. All patients tolerated the procedure well. There were no intraoperative complications. One patient developed transient dysphagia. Visual analog scale scores were 9.00 ± 1.10 preoperative and 3.73 ± 1.85 at 2 weeks and 1.67 ± 1.66 at 3 months after the procedure and continued to stay low during the remainder of the follow-up (4-60 months). The Karnofsky performance status improved from 72.73 ± 11.04 preoperatively to 82.22 ± 8.33 at 2 weeks and 86.67 ± 5.00 at 3 months after the procedure. There was no evidence of new occurrence or progression of C2 fractures.

CONCLUSION

The anterior kyphoplasty using a steerable osteotome for tumors of the axis can result in lasting pain reduction and improved cervical stability while demonstrating a low complication rate.

The Dosimetric Outcome of a Rotational Planning Target Volume in Patients With Oropharyngeal Cancers

An isotropic expanded Planning Target Volume (PTV) neglects patient's off-axis rotation. This study designs a rotational PTV that is used instead of the standard 3-mm Clinical Target Volume (CTV) expanded PTV in oropharyngeal cancers with the goal to reduce pharyngeal constrictor muscle (PCM) mean dose. 10 patients were retrospectively evaluated. For off-axis rotation, the image was rotated around the longitudinal axis (cervical spinal canal) ± 5 degrees. These new CTVs were combined to form the rotational PTV. The standard and rotational treatment plans were designed with the goal to keep the superior and middle PCM-CTV70 mean dose to less than 50 Gy. There were a 355 cGy reduction in the superior PCM mean dose (form 5332 to 4977 cGy) and a 506 cGy reduction in middle PCM mean dose (from 4185 to 3679 cGy). 60% of patients may have at least a 20% reduction in dysphagia probability based on a Normal Tissue Complication Probability (NTCP) formula. The superior and middle PCM mean dose were reduced to less than 50 Gy in 40 and 20% of cases. There was an association between superior PCM mean dose and overlap volume of PTV70 and superior PCM in both standard (r = 0.92, p = 0.001) and rotational (r = 0.84, p = 0.002) plans. This association was present for middle PCM and PTV70 (r = 0.52, p = 0.02 and r = 0.62, p = 0.006). Rotational PTV can lower the mean dose to superior and middle PCMs, ultimately leading to lower dysphagia rates.

Feasibility of Mobile and Sensor Technology for Remote Monitoring in Cancer Care and Prevention

Objectives. Remote monitoring (RM) of health-related outcomes may optimize cancer care and prevention outside of clinic settings. CYCORE is a software-based system for collection and analyses of sensor and mobile data. We evaluated CYCORE's feasibility in studies assessing: (1) physical functioning in colorectal cancer (CRC) patients; (2) swallowing exercise adherence in head and neck cancer (HNC) patients during radiation therapy; and (3) tobacco use in cancer survivors post-tobacco treatment (TTP). Methods. Participants completed RM: for CRC, blood pressure, activity, GPS; for HNC, video of swallowing exercises; for TTP, expired carbon monoxide. Patient-reported outcomes were assessed daily. Results. For CRC, HNC and TTP, respectively, 50, 37, and 50 participants achieved 96%, 84%, 96% completion rates. Also, 91-100% rated ease and self-efficacy as highly favorable, 72-100% gave equivalent ratings for overall satisfaction, 72-93% had low/no data privacy concerns. Conclusion. RM was highly feasible and acceptable for patients across diverse use cases.

Change in dysphagia and laryngeal function after radical radiotherapy in laryngo pharyngeal malignancies - a prospective observational study

Background

Intensity modulated radiotherapy (IMRT) has the perceived advantage of function preservation by reduction of toxicities in the treatment of laryngo-pharyngeal malignancies. The aim of the study was to assess changes in dysphagia from baseline (i.e. prior to start of treatment) at three and six months post treatment in patients with laryngo-pharyngeal malignancies treated with radical radiotherapy ± chemotherapy. Functional assessment of other structures involved in swallowing was also studied.

Materials and methods

40 patients were sampled consecutively. 33 were available for final analysis. Dysphagia, laryngeal edema, xerostomia and voice of patients were assessed at baseline and at three and six months after treatment. Radiation was delivered with simultaneous integrated boost (SIB) using volumetric modulated radiation therapy (VMAT). Concurrent chemotherapy was three weekly cisplatin 100 mg/m².

Results

Proportion of patients with dysphagia rose significantly from 45.5% before the start of treatment to 57.6% at three months and 60.6% at six months post treatment (p = 0.019). 67% patients received chemotherapy and addition of chemotherapy had a significant correlation with dysphagia (p = 0.05, r = -0.336). Severity of dysphagia at three and six months correlated significantly with the mean dose received by the superior constrictors (p = 0.003, r = 0.508 and p = 0.024, r = 0.391) and oral cavity (p = 0.001, r = 0.558 and p = 0.003, r = 0.501). There was a significant worsening in laryngeal edema at three and six months post treatment (p < 0.01) when compared to the pre-treatment examination findings with 60.6% of patients having grade two edema at six months. Significant fall in the mean spoken fundamental frequency from baseline was seen at 6 months (p = 0.04), mean fall was 21.3 Hz (95% CI: 1.5-41 Hz) with significant increase in roughness of voice post treatment (p = 0.01).

Conclusion

There was progressive worsening in dysphagia, laryngeal edema and voice in laryngo-pharyngeal malignancies post radical radiotherapy ± chemotherapy.

Patient-Reported Outcomes-Guided Adaptive Radiation Therapy for Head and Neck Cancer

Purpose

To identify which patient-reported outcomes (PROs) may be most improved through adaptive radiation therapy (ART) with the goal of reducing toxicity incidence among head and neck cancer patients.

Methods

One hundred fifty-five head and neck cancer patients receiving radical VMAT (chemo)radiotherapy (66-70 Gy in 30-35 fractions) completed the MD Anderson Symptom Inventory, MD Anderson Dysphagia Inventory (MDADI), and Xerostomia Questionnaire while attending routine follow-up clinics between June-October 2019. Hierarchical clustering characterized symptom endorsement. Conventional statistical approaches indicated associations between dose and commonly reported symptoms. These associations, and the potential benefit of interfractional dose corrections, were further explored via logistic regression.

Results

Radiotherapy-related symptoms were commonly reported (dry mouth, difficulty swallowing/chewing). Clustering identified three patient subgroups reporting: none/mild symptoms for most items (60.6% of patients); moderate/severe symptoms affecting some aspects of general well-being (32.9%); and moderate/severe symptom reporting for most items (6.5%). Clusters of PRO items broadly consisted of acute toxicities, general well-being, and head and neck-specific symptoms (xerostomia, dysphagia). Dose-PRO relationships were strongest between delivered pharyngeal constrictor Dmean and patient-reported dysphagia, with MDADI composite scores (mean ± SD) of 25.7 ± 18.9 for patients with Dmean <50 Gy vs. 32.4 ± 17.1 with Dmean ≥50 Gy. Based on logistic regression models, during-treatment dose corrections back to planned values may confer ≥5% decrease in the absolute risk of self-reported physical dysphagia symptoms ≥1 year post-treatment in 1.2% of patients, with a ≥5% decrease in relative risk in 23.3% of patients.

Conclusions

Patient-reported dysphagia symptoms are strongly associated with delivered dose to the pharyngeal constrictor. Dysphagia-focused ART may provide the greatest toxicity benefit to head and neck cancer patients, and represent a potential new direction for ART, given that the existing ART literature has focused almost exclusively on xerostomia reduction.

Dosimetric justification for the use of volumetric modulated arc therapy in head and neck cancer-A systematic review of the literature

INTRODUCTION

Radiotherapy for head and neck cancer (HNC) has evolved rapidly in the past decades from conformal three-dimensional technique (3D-CRT) to intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT). This paper presents a dosimetric comparative study between VMAT and IMRT delivery based on current literature, while also presenting the potential challenges encountered with volumetric arc therapy.

METHODS

A systematic search of the scientific literature was conducted within Medline/Pubmed databases. A number of 13 papers fulfilled the search criteria which was based on the main objective to evaluate dosimetric characteristics of comparative treatment delivery with VMAT vs IMRT in HNC.

RESULTS

Overall, from a dosimetric perspective, dose delivery via VMAT and IMRT present comparable results. Beside the delivery technique, target volume coverage also depends on the planner's expertise as well as the employed planning algorithm. At times, the superiority of VMAT emerges from the improved sparing of normal tissue, reduction of monitor units (MU) and of treatment delivery time. Similar to IMRT, one of the most important challenges of VMAT is the risk of developing secondary cancer due to the higher number of MUs compared to 3D-CRT.

CONCLUSIONS

Based on the comparative results with the more established IMRT, VMAT in HNC can be safely delivered either as a single treatment or combined with other techniques.

Radiologic criteria of retropharyngeal lymph node metastasis in maxillary sinus cancer

Objective

To determine the most appropriate radiologic criteria of metastatic retropharyngeal lymph nodes (RLNs) in patients with maxillary sinus cancer (MSC).

Materials and methods

We retrospectively evaluated 16 consecutive patients who underwent magnetic resonance imaging (MRI) before and after the treatment of locally advanced squamous cell carcinoma of the maxillary sinus. The minimal and maximal diameters of all RLNS were recorded. RLNs were classified as metastatic on the basis of the MRI follow-up (f/u). RLNs were considered non-metastatic if stable disease continued until the final MRI f/u and metastatic in cases with different evaluations (complete response, partial response, progressive disease) determined using Response Evaluation Criteria in Solid Tumours (RECIST) ver. 1.1. The receiver operating characteristic curve (ROC) and area under the curve (AUC) were used to assess the accuracy of various criteria in the diagnosis of metastatic RLNs.

Results

Of the 34 RLNs in 16 cases observed on pretreatment MRI, 7 were classified as metastatic RLNs and 27 as non-metastatic RLNs. Using the radiologic criteria, metastatic RLNs tended to be diagnosed more accurately with the minimal axial diameter than with the maximal axial diameter (AUC; 0.97 vs. 0.73, p = 0.06). The most accurate size criterion of metastatic RLNs was a minimal axial diameter of 5 mm or larger, with an accuracy of 94.1% (32 of 34).

Conclusions

The most appropriate radiologic criterion of metastatic RLNs in MSC is a minimal axial diameter of 5 mm or longer.

Review of prophylactic swallowing interventions for head and neck cancer

BACKGROUND

Head and neck cancer treatment destroys nerves and/or organs associated with swallowing. Previous studies have investigated the efficacy of exercises for muscles used in swallowing before treatment in reducing disuse atrophy and delaying the occurrence of muscle fibrosis. However, the rehabilitation effects of training and the optimal intervention strategy are unknown.

OBJECTIVES

To establish evidence for the efficacy of prophylactic swallowing interventions in reducing aspiration and restoring oral intake in patients with head and neck cancer with dysphagia.

METHODS

We searched electronic databases (PubMed, Embase, Cochrane and MEDLINE) for studies published up to June 2021 reporting outcomes following prophylactic swallowing interventions in patients with head and neck cancer with dysphagia and the related influencing factors. The methodological quality of the literature was assessed using the Joanna Briggs Institute appraisal tools.

RESULTS

The search identified 1468 articles, and 13 studies were eventually included. Four categories involving 12 different swallowing interventions were classified. Regarding the descriptive analysis of the rehabilitation effects across all studies, in terms of oropharyngeal safety, five studies showed that swallowing interventions reduced the risk of aspiration, penetration or residue. In terms of oral intake and tube feeding dependence, four studies demonstrated reduced time to return to oral intake in the intervention group compared with the control group. In terms of intervention adherence, three studies showed that speech-language pathologist- and nurse-supervised training was a potential promoter of adherence, and five studies showed that the negative factors affecting adherence included pain, fatigue, forgetting, smoking, decreased exercise motivation, side effects of radiotherapy and distance to the rehabilitation site.

CONCLUSIONS

Preventive swallowing interventions may be effective at reducing aspiration, improving swallowing function, and restoring oral intake. However, due to the lack of standardization and consistency of interventions and measurement results, which prevented the production of a best practice guide, future rigorous methodological trials will be needed to determine the most effective interventions for maximizing exercise adherence over the long term.

Radiation-induced swallowing dysfunction in patients with head and neck cancer: A literature review

Swallowing dysfunction is a prevailing state following radiotherapy in patients with head and neck cancer. Following the advancement of cancer treatment in recent years, the survival rate of head and neck cancer has gradually increased. Simultaneously, patients with head and neck cancer suffer due to the long-duration and more prominent swallowing dysfunction states. Based on an extensive literature review, we aimed to explore the mechanisms, risk factors, and clinical evaluations of swallowing dysfunction and their related symptoms following radiotherapy. These include functional changes of the muscles, trismus, xerostomia, neuropathy, and lymphedema. When swallowing dysfunction occurs, patients usually seek medical help and are referred for rehabilitation therapy, such as muscle strengthening and tongue resistance exercise. Furthermore, clinicians should discuss with patients how and when to place the feeding tube. Only through detailed evaluation and management can swallowing dysfunction resolve and improve the quality of life of patients with head and neck cancer following radiotherapy.

National Protocol for Model-Based Selection for Proton Therapy in Head and Neck Cancer

In the Netherlands, the model-based approach is used to identify patients with head and neck cancer who may benefit most from proton therapy in terms of prevention of late radiation-induced side effects in comparison with photon therapy. To this purpose, a National Indication Protocol Proton therapy for Head and Neck Cancer patients (NIPP-HNC) was developed, which has been approved by the health care authorities. When patients qualify according to the guidelines of the NIPP-HNC, proton therapy is fully reimbursed. This article describes the procedures that were followed to develop this NIPP-HNC and provides all necessary information to introduce model-based selection for patients with head and neck cancer into routine clinical practice.

Determining Clinical Patient Selection Guidelines for Head and Neck Adaptive Radiation Therapy Using Random Forest Modelling and a Novel Simplification Heuristic

Purpose

To determine which head and neck adaptive radiotherapy (ART) correction objectives are feasible and to derive efficient ART patient selection guidelines.

Methods

We considered various head and neck ART objectives including independent consideration of dose-sparing of the brainstem/spinal cord, parotid glands, and pharyngeal constrictor, as well as prediction of patient weight loss. Two-hundred head and neck cancer patients were used for model development and an additional 50 for model validation. Patient chart data, pre-treatment images, treatment plans, on-unit patient measurements, and combinations thereof were assessed as potential predictors of each objective. A stepwise approach identified combinations of predictors maximizing the Youden index of random forest (RF) models. A heuristic translated RF results into simple patient selection guidelines which were further refined to balance predictive capability and practical resource costs. Generalizability of the RF models and simplified guidelines to new data was tested using the validation set.

Results

Top performing RF models used various categories of predictors, however, final simplified patient selection guidelines only required pre-treatment information for ART predictions, indicating the potential for significant ART process streamlining. The simplified guidelines for each objective predicted which patients would experience increases in dose to: brainstem/spinal cord with sensitivity = 1.0, specificity = 0.66; parotid glands with sensitivity = 0.82, specificity = 0.70; and pharyngeal constrictor with sensitivity = 0.84, specificity = 0.68. Weight loss could be predicted with sensitivity = 0.60 and specificity = 0.55. Furthermore, depending on the ART objective, 28%-58% of patients required replan assessment, less than for previous studies, indicating a step towards more effective patient selection.

Conclusions

The above ART objectives appear to be practically achievable, with patients selected for ART according to simple clinical patient selection guidelines. Explicit ART guidelines are rare in the literature, and our guidelines may aid in balancing the potential clinical gains of ART with high associated resource costs, formalizing ART trials, and ensuring the reproducibility of clinical successes.

Gene alterations as predictors of radiation-induced toxicity in head and neck squamous cell carcinoma

Background

Optimizing the therapeutic ratio for radiation therapy (RT) in head and neck squamous cell carcinoma (HNSCC) is uniquely challenging owing to high rates of early and late toxicity involving nearby organs at risk. These toxicities have a profound impact on treatment compliance and quality of life. Emerging evidence suggests that RT dose alone cannot fully account for the variable severity of RT-related adverse events (rtAEs) observed in HNSCC patients. Next-generation sequencing has become an increasingly valuable tool with widespread use in the oncology field and is being robustly explored for predicting rtAEs beyond dosimetric data.

Methods

Patients who had Foundation Medicine sequencing data and received RT for primary or locally recurrent HNSCC were selected for this study. Early and late toxicity data were collected and reported based on Common Terminology Criteria for Adverse Events version 5.0. Dosimetric parameters were collected for pertinent structures.

Results

A total of HNSCC 37 patients were analyzed in this study. Genetic alterations in BRCA2, ERBB3, NOTCH1 and CCND1 were all associated with higher mean grade of toxicity with BRCA2 alteration implicated in all toxicity parameters evaluated including mucositis, early dysphagia, xerostomia and to a lesser extent, late dysphagia. Interestingly, patients who exhibited alterations in both BRCA2 and ERBB3 experienced a twofold or greater increase in early dysphagia, early xerostomia and late dysphagia compared to ERBB3 alteration alone. Furthermore, several gene alterations were associated with improved toxicity outcomes. Within an RT supersensitive patient subset, alterations were found in TNFAIP3, HNF1A, SPTA1 and CASP8. All of these alterations were not found in the RT insensitive patient subset. We found 17 gene alterations in the RT insensitive patient subset that were not found in the RT supersensitive patient subset.

Conclusion

Despite consistent RT dosimetric parameters, patients with HNSCC experience heterogeneous patterns of rtAEs. Identifying factors associated with toxicity outcomes offers a new avenue for personalized precision RT therapy and prophylactic management. Here, next-generation sequencing in a population of HNSCC patients correlates several genetic alterations with severity of rtAEs. Further analysis is urgently needed to identify genetic patterns associated with rtAEs in order to reduce harmful outcomes in this challenging population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02876-5.

De-Escalation Strategies of (Chemo)Radiation for Head-and-Neck Squamous Cell Cancers-HPV and Beyond

Oncological outcomes for head-and-neck squamous cell carcinoma (HNSCC) patients are still unsatisfactory, especially for advanced tumor stages. Besides the moderate survival rates, the prevalence of severe treatment-induced normal tissue toxicities is high after multimodal cancer treatments, both causing significant morbidity and decreasing quality of life of surviving patients. Therefore, risk-adapted and individualized treatment approaches are urgently needed for HNSCC patients to optimize the therapeutic gain. It has been a well-known fact that especially HPV-positive oropharyngeal squamous cell carcinoma (OSCC) patients exhibit an excellent prognosis and may therefore be subject to overtreatment, resulting in long-term treatment-related toxicities. Regarding the superior prognosis of HPV-positive OSCC patients, treatment de-escalation strategies are currently investigated in several clinical trials, and HPV-positive OSCC may potentially serve as a model for treatment de-escalation also for other types of HNSCC. We performed a literature search for both published and ongoing clinical trials and critically discussed the presented concepts and results. Radiotherapy dose or volume reduction, omission or modification of concomitant chemotherapy, and usage of induction chemotherapy are common treatment de-escalation strategies that are pursued in clinical trials for biologically selected subgroups of HNSCC patients. While promising data have been reported from various Phase II trials, evidence from Phase III de-escalation trials is either lacking or has failed to demonstrate comparable outcomes for de-escalated treatments. Therefore, further data and a refinement of biological HNSCC stratification are required before deescalated radiation treatments can be recommended outside of clinical trials.

[De-escalation concepts for chemoradiotherapy of HPV-positive oropharyngeal carcinomas: pros and cons]

BACKGROUND

In contrast to alcohol- and nicotine-induced head and neck tumors, human papillomavirus (HPV)-positive oropharyngeal carcinoma rather affects younger patients, and the incidence of this entity is continuously increasing. Due to the significantly better prognosis of HPV-positive oropharyngeal carcinoma, various treatment de-escalation strategies are currently being investigated, with the aim of reducing toxicity without affecting the good survival rates of these patients.

OBJECTIVE

This study aims to evaluate the evidence for treatment de-escalation in HPV-positive oropharyngeal carcinoma.

MATERIALS AND METHODS

A literature search was performed and relevant studies are critically discussed.

RESULTS

De-escalation strategies for HPV-associated oropharyngeal carcinoma using induction chemotherapy or radiation dose reduction have demonstrated good oncological results in phase II trials, with lower toxicity rates compared to historical controls. However, both of the first published phase III trials investigating de-escalation of concomitant chemotherapy regimens demonstrated inferior outcomes for the deescalated treatment strategies without improvements in treatment-associated toxicities. Additional phase-III trials investigating other de-escalation strategies have not yet been published.

CONCLUSION

Treatment de-escalation should be performed exclusively in prospective studies and can currently not be recommended in clinical routine.

Influence of radiation dose to pharyngeal constrictor muscles on late dysphagia and quality of life in patients with locally advanced oropharyngeal carcinoma

BACKGROUND AND OBJECTIVE

Patients with oropharyngeal carcinoma (OPC) often have difficulty swallowing, which may affect quality of life (QoL). Radiation dose to constrictor muscles plays an important role.

METHODS

54 patients with locally advanced OPC were evaluated after intensity-modulated radiotherapy. Data were collected at standardized intervals using the EORTC questionnaires QLQ-C30 and QLQ-HN35 within two years. The pharyngeal constrictors (superior, middle, and inferior) were each contoured as an organ at risk. Influence of dose to the constrictors (≥55 Gy vs. <55 Gy) on late dysphagia and QoL was analyzed using the t‑test.

RESULTS

Late radiation-induced dysphagia depends significantly on the dose to the lower pharyngeal constrictor. At a dose of ≥55 Gy, 14 (64%) patients developed dysphagia grade ≤2 and 8 (36%) patients grade ≥3. At a dose of <55 Gy, the distribution at the end of radiotherapy (RT) was similar: 22 (69%) patients with dysphagia grade ≤2, 10 (31%) with grade ≥3. There was no dose-dependent difference in the severity of dysphagia in the acute phase (p = 0.989). There were differences 18 months after the end of RT: ≥55 Gy: 19 (86%) patients showed dysphagia grade ≤2; 3 (14%) grade ≥3. At <55 Gy, 31 (97%) patients developed grade ≤2, 1 (3%) grade ≥3 (18 months: p = 0.001; 24 months: p = 0.000). Late dysphagia is also dependent on the dose level of the middle constrictor muscle (6 months: p = 0.000; 12 months: p = 0.005, 18 months: p = 0.034). After 24 months, there was no significant difference (p = 0.374).

CONCLUSION

Radiation dose to the upper constrictor muscle appears to be of little relevance. The middle and lower constrictor should be given special consideration to avoid late dysphagia. Long-term QoL is independent on radiation dose.

Combination of a Big Data Analytics Resource System With an Artificial Intelligence Algorithm to Identify Clinically Actionable Radiation Dose Thresholds for Dysphagia in Head and Neck Patients

Purpose

We combined clinical practice changes, standardizations, and technology to automate aggregation, integration, and harmonization of comprehensive patient data from the multiple source systems used in clinical practice into a big data analytics resource system (BDARS). We then developed novel artificial intelligence algorithms, coupled with the BDARS, to identify structure dose volume histograms (DVH) metrics associated with dysphagia.

Methods and Materials

From the BDARS harmonized data of ≥22,000 patients, we identified 132 patients recently treated for head and neck cancer who also demonstrated dysphagia scores that worsened from base line to a maximum grade ≥2. We developed a method that used both physical and biologically corrected (α/β = 2.5) DVH curves to test both absolute and percentage volume based DVH metrics. Combining a statistical categorization algorithm with machine learning (SCA-ML) provided more extensive detailing of response threshold evidence than either approach alone. A sensitivity guided, minimum input, machine learning (ML) model was iteratively constructed to identify the key structure DVH metric thresholds.

Results

Seven swallowing structures producing 738 candidate DVH metrics were ranked for association with dysphagia using SCA-ML scoring. Structures included superior pharyngeal constrictor (SPC), inferior pharyngeal constrictor (IPC), larynx, and esophagus. Bilateral parotid and submandibular gland (SG) structures were categorized by relative mean dose (eg, SG_high, SG_low) as a dose versus tumor centric analog to contra and ipsilateral designations. Structure DVH metrics with high SCA-ML scores included the following: SPC: D20% (equivalent dose [EQD2] Gy) ≥47.7; SPC: D25% (Gy) ≥50.4; IPC: D35% (Gy) ≥61.7; parotid_low: D60% (Gy) ≥13.2; and SG_high: D35% (Gy) ≥61.7. Larynx: D25% (Gy) ≥21.2 and SG_low: D45% ≥28.2 had high SCA-ML scores but were segmented on less than 90% of plans. A model based on SPC: D20% (EQD2 Gy) alone had sensitivity and area under the curve of 0.88 ± 0.13 and 0.74 ± 0.17, respectively.

Conclusions

This study provides practical demonstration of combining big data with artificial intelligence to increase volume of evidence in clinical learning paradigms.

The Changes in Pharyngeal Constrictor Muscles Related to Head and Neck Radiotherapy: A Systematic Review

It is well known that radiation damage of the pharyngeal constrictor muscles, the glottic larynx, and the supraglottic larynx may lead to dysphagia, an unwanted effect of head and neck radiotherapy. The reduction of radiotherapy-induced dysphagia might be achieved by adaptive radiotherapy. Although the number of studies concerning adaptive radiotherapy of head and neck cancer is continuously increasing, there are only a few studies concerning changes in dysphagia-related structures during radiotherapy.The goal of this review is to summarize the current knowledge about volumetric, dosimetric, and other changes of the pharyngeal constrictor muscles associated with head and neck radiotherapy. A literature search was performed in the MEDLINE database according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The conclusions of 8 studies that passed the criteria indicate a significant increase in the volume and the thickness of the pharyngeal constrictor muscles during radiotherapy. Moreover, the changes in magnetic resonance imaging signal intensity of the pharyngeal constrictor muscles correlate with the absorbed dose (typically higher than 50 Gy) and also with the grade of dysphagia. This systematic review presents 2 variables, which are suitable for estimation of radiotherapy-related pharyngeal constrictor muscles changes-magnetic resonance imaging signal intensity and the thickness. In the case of the thickness, there is no consensus in the level of the measurement-C2 vertebra, C3 vertebra, and the middle of the craniocaudal axis are used. It seems that reference to a position associated with a vertebral body could be more reproducible and beneficial for future research. Although late pharyngeal toxicity remains a challenge in head and neck cancer treatment, better knowledge of radiotherapy-related changes in the pharyngeal constrictor muscles contributes to adaptive radiotherapy development and thus improves the treatment results.

Organ Preservation and Late Functional Outcome in Oropharyngeal Carcinoma: Rationale of EORTC 1420, the "Best of" Trial

Dysphagia represents one of the most serious adverse events after curative-intent treatments with a tremendous impact on quality of life in patients with head and neck cancers. Novel surgical and radiation therapy techniques have been developed to better preserve swallowing function, while not negatively influencing local control and/or overall survival. This review focuses on the current literature of swallowing outcomes after curative treatment strategies. Available results from recent studies relevant to this topic are presented, demonstrating the potential role of new treatment modalities for early- and intermediate-stage oropharyngeal cancers. Based on this, we present the rationale and design of the currently active EORTC 1420 "Best of" trial, and highlight the potential of this study to help prioritizing either surgery- or radiation-based treatment modalities for the treatment of oropharyngeal cancer in the future.

Optimizing laryngeal sparing with intensity modulated radiotherapy or volumetric modulated arc therapy for unilateral tonsil cancer

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Early stage tonsillar cancers may be treated with unilateral neck radiotherapy (RT).

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We performed a dosimetric study comparing three common radiotherapy modalities.

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No significant differences in target coverage existed between all plans.

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Laryngeal doses were reduced using whole-field intensity modulated RT and VMAT.

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Shorter treatment times and required monitor units were also associated with VMAT.

Background and purpose

Minimizing radiation dose exposure to nearby organs is key to limiting clinical toxicities associated with radiotherapy. Several treatment modalities such as split- or whole-field intensity-modulated radiotherapy (SF-IMRT, WF-IMRT) and volumetric modulated arc therapy (VMAT) are being used to treat tonsillar cancer patients with unilateral neck radiotherapy. Herein, we provide a modern dosimetric comparison of all three techniques.

Materials and methods

Forty patients with tonsillar cancer treated with definitive, ipsilateral neck SF-IMRT were evaluated. Each patient was re-planned with WF-IMRT and VMAT techniques, and doses to selected organs-at-risk (OARs) including the larynx, esophagus, and brainstem were compared.

Results

No significant differences in target coverage existed between plans; however, the heterogeneity index improved using WF-IMRT and VMAT relative to SF-IMRT. Compared to SF-IMRT, WF-IMRT and VMAT plans had significantly lower mean doses to the supraglottic larynx (31 Gy, 18.5 Gy, 17 Gy; p < 0.01), the MDACC-defined larynx (13.4 Gy, 10.5 Gy, 9.8 Gy; p < 0.01), and RTOG-defined larynx (15.8 Gy, 12.1 Gy, 11.1 Gy; p < 0.01), respectively. Mean esophageal dose was lowest with SF-IMRT over WF-IMRT and VMAT (5.9 Gy, 12.2 Gy, 11.1 Gy; p < 0.01) but only in the absence of lower neck disease. On average, VMAT plans had shorter treatment times and required less monitor units than both SF-IMRT and WF-IMRT.

Conclusion

In the setting of unilateral neck radiotherapy, WF-IMRT and VMAT plans can be optimized to significantly improve dose sparing of critical structures compared to SF-IMRT. VMAT offers additional advantages of shorter treatment times and fewer required monitor units.

Perspectives on optimizing radiotherapy dose to the dysphagia/aspiration-related structures for patients with head and neck cancer

PURPOSE OF REVIEW

The purpose of this study is to provide an overview on the methodologies, outcomes and clinical implications of studies that have investigated swallowing outcomes after head and neck cancer (HNC) treatment when reducing radiotherapy dose to specific dysphagia/aspiration-related structures (DARS).

RECENT FINDINGS

Overall, there is limited recent evidence, with a lack of high-quality studies, which examine the outcomes of DARS-optimized radiotherapy treatment. Large variations exist in the methodology of these studies in regards to which DARS are delineated and how swallowing outcomes are measured. Consequently, there is a wide range of dose limits recommended to a variety of DARS structures. Despite these limitations, there appears to be a general consensus that optimizing dose to the DARS will result in some reduction of dysphagia after radiotherapy without compromising on treatment to the tumour.

SUMMARY

More rigorous study must be completed to determine the true extent of clinical benefit from this practice. Institutions must take into consideration the limitations of the evidence as well as logistical costs of implementing this technique into practice. However, optimizing dose to the DARS appears to be a well-tolerated practice that may have substantial positive benefits for patients' swallowing function and quality of life after HNC treatment.

Dysphagia optimized radiotherapy to reduce swallowing dysfunction severity in patients undergoing treatment for head and neck cancer: A systematized scoping review

This study involved a systematized scoping review to coalesce current evidence on dysphagia outcomes achieved through active sparing of the swallowing structures in patients receiving radiotherapy for head and neck cancer. Eligible publications between 2007 and 2017 were reviewed and synthesized regarding participant demographics, treatment regimens, swallowing structures chosen for optimization, dosimetric constraints, and dysphagia measures. Nine prospective cohort studies were included. Key structures routinely spared included pharyngeal constrictor muscles (PCMs), glottic larynx (GL), supraglottic larynx (SGL), and esophageal inlet muscle. Shorter enteral feeding times and reductions in Common Terminology Criteria for Adverse Event (CTCAE) grade 3 dysphagia toxicity were observed when dose to the larynx (GL and SGL) and PCMs was constrained to < 50 and < 60 Gy, respectively. Emerging evidence supports "active" sparing of the swallowing structures at the time of radiotherapy planning to reduce dysphagia severity, with no compromise to planning target volumes and locoregional control rates.

Systematic review and meta-analysis of the impact of dosimetry to dysphagia and aspiration related structures

BACKGROUND

Technological advances in radiotherapy have allowed investigations into new methods to spare healthy tissue in those treated for head and neck cancer. This systematic review with meta-analysis demonstrates the effect that radiation has on swallowing.

METHODS

Selection and analysis of studies examining the effect of radiation to swallowing structures. A fixed effects meta-analysis calculated the pooled proportions for select outcomes of dysphagia, common across many studies.

RESULTS

The majority of the papers found a correlation between radiation dose to the swallowing structures and dysphagia, however a meta-analysis found the studies carried a significant degree of heterogeneity. The appraisal demonstrates the need for large-scale studies using a randomized design and instrumental dysphagia assessments.

CONCLUSIONS

Radiation dose to dysphagia and aspiration structures is correlated with incidence of dysphagia and aspiration. The variables in this population contribute to the heterogeneity within and cross studies and future studies should consider controlling for this.

Omitting Elective Irradiation of the Contralateral Retropharyngeal Nodes in Oropharyngeal Squamous Cell Carcinoma Treated with Intensity-modulated Radiotherapy

Introduction: The use of intensity-modulated radiation therapy (IMRT) in head and neck cancers has allowed for selective sparing of low-risk or uninvolved lymph nodes. In oropharyngeal cancers, the benefits and risks of omitting contralateral retropharyngeal lymph nodes (RPLN) remain uncertain. This study examines the outcomes of elective coverage of contralateral RPLN in oropharyngeal cancer treated with definitive IMRT.

Methods: We analyzed 54 patients with newly diagnosed unilateral tonsil or base of tongue squamous cell carcinoma with at most unilateral neck involvement (cN0-N2b) and no RPLN involvement. These patients had no prior head and neck irradiation and were treated with definitive radiotherapy or chemoradiotherapy between 2012 and 2017. Cumulative incidences of local/regional/distant failure were estimated using competing risks methodology, and overall survival (OS) was estimated using the Kaplan-Meier method.

Results: All patients received elective nodal coverage to the ipsilateral RPLN, and 38 (62%) patients did not receive elective treatment of the contralateral RPLN. There were no significant differences in baseline characteristics. There were no contralateral RPLN failures observed. When comparing patients who received contralateral RP treatment with those who did not, there were no significant differences in two-year local failure (23% vs. 9%, p = 0.09), regional failure (18% vs. 4%, p = 0.12), or distant failure (15% vs. 9%, p = 0.62). Two-year OS was 89%. Mean parotid dose was not significantly lower after sparing vs. treating the contralateral RPLN (median 25.6 vs. 32.7 Gy, p = 0.15).

Conclusions: The omission of contralateral RPLN irradiation in tonsil or tongue base carcinomas with unilateral neck involvement is safe without compromising disease control.

Radiation-induced late dysphagia after intensity-modulated radiotherapy in nasopharyngeal carcinoma patients: a dose-volume effect analysis

Dysphagia is a side effect of nasopharyngeal carcinoma chemo-radiotherapy (CRT) which greatly influences the quality of life of the patients. We analyzed late dysphagia in 134 patients with nasopharyngeal cancer undergoing radical radiotherapy (RT), and correlated these findings with dose–volume histogram (DVH) parameters of the swallowing organs at risk (SWOARs). DVH parameters of SWOARs were correlated with late dysphagia, and with RTOG/EORTC scale score and the M. D. Anderson dysphagia inventory (MDADI) score. The mean dose (D_mean) to the superior and inferior constrictor muscles (SCM and ICM) and age were associated with grade 2 late dysphagia. Receiver operating characteristic (ROC) curves showed that the threshold values for grade 2 late dysphagia were: D_mean to SCM ≥ 67 Gy, partial volume receiving specified dose of 60 Gy (V₆₀) of SCM ≥ 95%, D_mean to ICM ≥ 47 Gy, and V₅₀ of ICM ≥ 23%. The areas under the ROC curve were 0.681 (p = 0.02), 0.677 (p = 0.002), 0.71 (p < 0.001) and 0.726 (p < 0.001) respectively. Our study demonstrates a significant relationship between late dysphagia and the radiation doses delivered to the SCM and ICM. Our findings suggest that physicians should be cautious in reducing the RT dose to SWOARs in order to avoid severe dysphagia. Further prospective trials are necessary to recommend this as part of routine clinical practice.

Revisiting the dose constraints for head and neck OARs in the current era of IMRT

Head and neck cancer poses a particular challenge in radiation therapy, whilst being an effective treatment modality it requires very high doses of radiation to provide effective therapy. This is further complicated by the fact that the head and neck region contains a large number of radiosensitive tissues, often resulting in patients experiencing debilitating normal tissue complications. In the era of intensity-modulated radiation therapy (IMRT) treatments can be delivered using non-uniform dose distributions selectively aimed at reducing the dose to critical organs-at-risk while still adequately covering the tumor target. Dose-volume constraints for the different risk organs play a vital role in one's ability to devise the best IMRT treatment plan for a head and neck cancer patient. To this end, it is pivotal to have access to the latest and most relevant dose constraints available and as such the goal of this review is to provide a summary of suggested dose-volume constraints for head and neck cancer RT that have been published after the QUANTEC reports were made available in early 2010.

Cricopharyngeal function or dysfunction: what's the deal?

PURPOSE OF REVIEW

The purpose of the review is to examine current research focused on upper oesophageal sphincter (UES) and cricopharyngeus muscle function, and how better understanding UES physiology will translate to improved management.

RECENT FINDINGS

Although much is known about UES function, new information describing the dynamics of the UES and cricopharyngeus is being identified through manometry, combined fluoromanometry, and anatomic study. Response of the UES to injury, reflux, and surgical interventions is reported. Direct surgical treatment of cricopharyngeus noncompliance with or without diverticuli continues to show benefit and long-term results support a sustained improvement in three-quarters of patients.

SUMMARY

UES and cricopharyngeus function is complex and dynamic. It is affected by internal signals such as posture and constitution of refluxate, aging, and interventions particularly radiation and surgery. Clear understanding of the triggers and responses of the UES will enable clinicians to choose the correct therapy for their dysphagic patients.

Systematic Review of Normal Tissue Complication Models Relevant to Standard Fractionation Radiation Therapy of the Head and Neck Region Published After the QUANTEC Reports

There has recently been an increasing interest in model-based evaluation and comparison of different treatment options in radiation oncology studies. This is partly driven by the considerable technical advancements in radiation therapy of the last decade, leaving radiation oncologists with a multitude of options to consider. In lieu of randomized trials comparing all of these different treatment options for varying indications, which is unfeasible, treatment evaluations based on normal tissue complication probability (NTCP) models offer a practical alternative. The Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) effort, culminating in a number of reports published in 2010, provided a basis for many of the since-implemented dose-response models and dose-volume constraints and was a key component for model-based treatment evaluations. Given that 7 years have passed since the QUANTEC publications and that patient-reported outcomes have emerged as an important consideration in recent years, an updated summary of the published radiation dose-response literature, which includes a focus on patient-reported quality of life outcomes, is warranted. Here we provide a systematic review of quantitative dose-response models published after January 1, 2010 for endpoints relevant to radiation therapy for head and neck cancer, because these patients are typically at risk for a variety of treatment-induced normal tissue complications.

Radiation-induced acute dysphagia : Prospective observational study on 42 head and neck cancer patients

PURPOSE

Acute toxicity in head and neck (H&N) cancer patients treated with definitive radiotherapy (RT) has a crucial role in compliance to treatments. The aim of this study was to correlate doses to swallowing-associated structures and acute dysphagia.

METHODS

We prospectively analyzed 42 H&N cancer patients treated with RT. Dysphagia (grade ≥ 3) and indication for percutaneous endoscopic gastrostomy (PEG) insertion were classified as acute toxicity. Ten swallowing-related structures were considered for the dosimetric analysis. The correlation between clinical information and the dose absorbed by the contoured structures was analyzed. Multivariate logistic regression method using resampling methods (bootstrapping) was applied to select model order and parameters for normal tissue complication probability (NTCP) modelling.

RESULTS

A strong multiple correlation between dosimetric parameters was found. A two-variable model was suggested as the optimal order by bootstrap method. The optimal model (Rs = 0.452, p < 0.001) includes V₄₅ of the cervical esophagus (odds ratio [OR] = 1.016) and D_mean of the cricopharyngeal muscle (OR = 1.057). The model area under the curve was 0.82 (95% confidence interval 0.69-0.95).

CONCLUSION

Our results suggested that the absorbed dose to the cricopharyngeal muscle and cervical esophagus might play a relevant role in the development of acute RT-related dysphagia.

Voxel-based analysis unveils regional dose differences associated with radiation-induced morbidity in head and neck cancer patients

The risk of radiation-induced toxicity in patients treated for head and neck (HN) cancer with radiation therapy (RT) is traditionally estimated by condensing the 3D dose distribution into a monodimensional cumulative dose-volume histogram which disregards information on dose localization. We hypothesized that a voxel-based approach would identify correlations between radiation-induced morbidity and local dose release, thus providing a new insight into spatial signature of radiation sensitivity in composite regions like the HN district. This methodology was applied to a cohort of HN cancer patients treated with RT at risk of radiation-induced acute dysphagia (RIAD). We implemented an inter-patient elastic image registration framework that proved robust enough to match even the most elusive HN structures and to provide accurate dose warping. A voxel-based statistical analysis was then performed to test regional dosimetric differences between patients with and without RIAD. We identified a significantly higher dose delivered to RIAD patients in two voxel clusters in correspondence of the cricopharyngeus muscle and cervical esophagus. Our study goes beyond the well-established organ-based philosophy exploring the relationship between radiation-induced morbidity and local dose differences in the HN region. This approach is generally applicable to different HN toxicity endpoints and is not specific to RIAD.

Dysphagia-optimised Intensity-modulated Radiotherapy Techniques in Pharyngeal Cancers: Is Anyone Going to Swallow it?

Dysphagia after primary chemoradiotherapy or radiation alone in pharyngeal cancers can have a devastating impact on a patient's physical, social and emotional state. Establishing and validating efficient dysphagia-optimised radiotherapy techniques is, therefore, of paramount importance in an era where health-related quality of life measures are increasingly influential determinants of curative management strategies, particularly as the incidence of good prognosis, human papillomavirus-driven pharyngeal cancer in younger patients continues to rise. The preferential sparing achievable with intensity-modulated radiotherapy (IMRT) of key swallowing structures implicated in post-radiation dysfunction, such as the pharyngeal constrictor muscles (PCM), has generated significant research into toxicity-mitigating strategies. The lack of randomised evidence, however, means that there remains uncertainty about the true clinical benefits of the dosimetric gains offered by technological advances in radiotherapy. As a result, we feel that IMRT techniques that spare PCM cannot be incorporated into routine practice. In this review, we discuss the swallowing structures responsible for functional impairment, analyse the studies that have explored the dose-response relationship between these critical structures and late dysphagia, and consider the merits of reported dysphagia-optimised IMRT (Do-IMRT) approaches, thus far. Finally, we discuss the dysphagia/aspiration-related structures (DARS) study (ISRCTN 25458988), which is the first phase III randomised controlled trial designed to investigate the impact of swallow-sparing strategies on improving long-term function. To maximise patient benefits, improvements in radiation delivery will need to integrate with novel treatment paradigms and comprehensive rehabilitation strategies to eventually provide a patient-centric, personalised treatment plan.

What is the role of postoperative re-irradiation in recurrent and second primary squamous cell cancer of head and neck? A literature review according to PICO criteria

Re-irradiation has been increasingly offered as a potential effective treatment for head and neck squamous cell carcinoma (HNSCC) loco-regional recurrence as well as second primary tumor in previously irradiated area. This review focused on the role of postoperative re-irradiation (POreRT) in terms of feasibility, toxicity and long-term outcomes in HNSCC patients. The key issue for the research was formulated in two questions according to the PICO (population, intervention, control, and outcomes) criteria. A total of 16 publications met the inclusion criteria for a total of 919 patients; in 522 patients POreRT was performed. POreRT in recurrent and second primary HNSCC seems to be feasible in highly selected patients with the intent to guarantee an acceptable LC compared to surgery alone. The optimal RT schedule remains unclear due to the heterogeneity of literature data.

Nasal cavity reirradiation: a challenging case for comparison between proton therapy and volumetric modulated arc therapy

BACKGROUND

The aim of this case report is to report on a dosimetric comparison between volumetric modulated arc therapy (RapidArc technique and active scanning proton therapy (single-field (SFO) and multifield (MFO) techniques) in a case of nasal cavity cancer recurrence.

CASE REPORT

A 72-year-old man, who received adjuvant radiotherapy for a carcinoma of the nasal cavity, experienced an unresectable local recurrence in the previous surgical bed. Hence, the patient was evaluated for reirradiation by comparing different modalities, with a total prescribed dose of 50 Gy in standard fractionation. RA plan was revealed to be equivalent to the MFO plan in terms of target dose coverage and conformity index. SFO plan was not able to respect a maximum dose of 9 Gy to nervous structures, in contrast to RA and MFO plans.

CONCLUSIONS

In this challenging scenario, although a clear preference would be given to the MFO proton plan, the RA plan was revealed to be adequate for the clinical goal of target coverage and sparing of organs at risk.

Treatment de-intensification strategies for head and neck cancer

Increasingly, squamous cell carcinoma of the oropharynx (OPSCC) is attributable to transformation resulting from high-risk human papillomavirus (HPV) infection. Such cancers are significantly more responsive to treatment than traditional tobacco- and alcohol-associated squamous cell cancers of the head and neck. Conventional management with definitive chemoradiation, surgery and adjuvant radiation, or radiation given with altered fractionation schemes, while effective, incurs long-term morbidity that escalates with treatment intensity and significantly impairs quality of life. Recent trials have suggested that less intensive treatment regimens may achieve similar efficacy with decreased toxicity. In this article, we review the primary strategies used for de-escalation of treatment, which include the reduction of radiation dose, substitution and/or elimination of concurrent radiosensitising chemotherapy, and the use of minimally invasive surgery. We discuss the rationale behind these approaches and the preliminary data demonstrating the success of de-escalation, as well as potential considerations raised by treatment de-intensification in HPV-associated OPSCC.

DARS: a phase III randomised multicentre study of dysphagia- optimised intensity- modulated radiotherapy (Do-IMRT) versus standard intensity- modulated radiotherapy (S-IMRT) in head and neck cancer

BACKGROUND

Persistent dysphagia following primary chemoradiation (CRT) for head and neck cancers can have a devastating impact on patients' quality of life. Single arm studies have shown that the dosimetric sparing of critical swallowing structures such as the pharyngeal constrictor muscle and supraglottic larynx can translate to better functional outcomes. However, there are no current randomised studies to confirm the benefits of such swallow sparing strategies. The aim of Dysphagia/Aspiration at risk structures (DARS) trial is to determine whether reducing the dose to the pharyngeal constrictors with dysphagia-optimised intensity- modulated radiotherapy (Do-IMRT) will lead to an improvement in long- term swallowing function without having any detrimental impact on disease-specific survival outcomes.

METHODS/DESIGN

The DARS trial (CRUK/14/014) is a phase III multicentre randomised controlled trial (RCT) for patients undergoing primary (chemo) radiotherapy for T1-4, N0-3, M0 pharyngeal cancers. Patients will be randomised (1:1 ratio) to either standard IMRT (S-IMRT) or Do-IMRT. Radiotherapy doses will be the same in both groups; however in patients allocated to Do-IMRT, irradiation of the pharyngeal musculature will be reduced by delivering IMRT identifying the pharyngeal muscles as organs at risk. The primary endpoint of the trial is the difference in the mean MD Anderson Dysphagia Inventory (MDADI) composite score, a patient-reported outcome, measured at 12 months post radiotherapy. Secondary endpoints include prospective and longitudinal evaluation of swallow outcomes incorporating a range of subjective and objective assessments, quality of life measures, loco-regional control and overall survival. Patients and speech and language therapists (SLTs) will both be blinded to treatment allocation arm to minimise outcome-reporting bias.

DISCUSSION

DARS is the first RCT investigating the effect of swallow sparing strategies on improving long-term swallowing outcomes in pharyngeal cancers. An integral part of the study is the multidimensional approach to swallowing assessment, providing robust data for the standardisation of future swallow outcome measures. A translational sub- study, which may lead to the development of future predictive and prognostic biomarkers, is also planned.

TRIAL REGISTRATION

This study is registered with the International Standard Randomised Controlled Trial register, ISRCTN25458988 (04/01/2016).

[Head and neck intensity-modulated radiation therapy: Normal tissues dose constraints. Pharyngeal constrictor muscles and larynx]

Radio-induced pharyngolaryngeal chronic disorders may challenge the quality of life of head and neck cancer long survivors. Many anatomic structures have been identified as potentially impaired by irradiation and responsible for laryngeal edema, dysphonia and dysphagia. Some dose constraints might be plausible such as keeping the mean dose to the pharyngeal constrictor muscles under 50 to 55Gy, the mean dose to the supra-glottic larynx under 40 to 45Gy and, if feasible, the mean dose to the glottic larynx under 20Gy. A reduction of the dose delivered to the muscles of the floor of the mouth and the cervical esophagus would be beneficial as well. Nevertheless, the publications available do not provide an extensive enough level of proof. One should consider limiting as low as possible the dose delivered to these structures without compromising the quality of irradiation of the target tumor volumes.

Effectiveness of tapentadol prolonged release for the management of painful mucositis in head and neck cancers during intensity modulated radiation therapy

PURPOSE

To evaluate the effectiveness and tolerability profile of tapentadol prolonged release (PR) in a cohort of head and neck cancer (HNC) patients affected by background pain due to painful mucositis during intensity modulated radiation therapy with or without cisplatin with definitive and adjuvant intent.

MATERIALS AND METHODS

Tapentadol PR was administered at the moment of pain onset in opioid-naive patients at the dosage of 50 mg BID. The dosage was increased 50 mg twice a day until the optimal dose of no more than 500 mg/day of tapentadol PR. Primary endpoint of the analysis was the evaluation of improved assessment using the numerical rating scale (NRS). Secondary endpoints were as follows: (1) assessment of the treatment received using the patients' global impression of change (PGIC) scale; (2) weight increase/stability; (3) sleep quality; and (4) tolerability. The period of observation was 90 days from the start of antineoplastic treatment.

RESULTS

Between September 2014 and May 2015, 30 HNC patients were observed. The average age was 64.9 years (range, 36-80). Twenty-two days after the start of antineoplastic treatment, tapentadol PR was administered to 25 % of patients. This percentage was increased to 50 % after 39 days and to 75 % after 43 days. Considering the efficacy of tapentadol PR on daily pain, there was a reduction of 30 % (95 % C.I. 69.3 ÷ 96.2 %) in the pain score in 26 patients (86.7 %), and a reduction of 50 % (95 % C.I. 57.7 ÷ 90.1 %) in 23 patients (76.7 %).

CONCLUSION

The use of tapentadol PR is feasible and well tolerated in HNC patients affected by background pain due to painful mucositis during intensity modulated radiotherapy with or without cisplatin. Further studies are needed to enhance current findings.