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

Feasibility of Achieving Dose Constraints for Dysphagia Aspiration-Related Structures and Its Clinical Significance in Intensity-Modulated Radiotherapy Planning of Head and Neck Cancer

Introduction Dysphagia is commonly seen in patients with head and neck cancers after undergoing chemoradiotherapy and is often under-reported and also not given clinical importance. The quality of life of the patients can be significantly improved if the required dose constraints to the dysphagia aspiration-related structures (DARS) are achieved. The present study was conducted in order to determine the feasibility of achieving the dose constraints to DARS between the standard intensity-modulated radiotherapy (st-IMRT) arm and the dysphagia-optimized IMRT (do-IMRT) arm. Material and methods Sixty patients with head and neck cancer were recruited and randomized into two groups: In one group called the st-IMRT, constraints were not given to DARS, and in the other group called the do-IMRT, constraints were given to DARS. Treatment was given in the form of chemoradiation with a dose of 70 Gy in 35 fractions by IMRT technique, over seven weeks, 2 Gy per fraction along with weekly concurrent Cisplatin (35 mg/m2) in both the groups. Step and shoot IMRT setup was used for planning, and the system used for planning was Eclipse 13.6 (Varian Medical System, Inc., Palo Alto, CA, US); progressive resolution optimizer algorithm was used for optimization, and Anisotropic Analytical Algorithm algorithm was used for dose calculation. Truebeam was used for treatment delivery. DARS dosimetric parameters assessed were Dmean, V30, V50, V60, V70, D50, and D80. Radiation-induced toxicities to the skin, mucosa, larynx, salivary gland, and dysphagia and hematological toxicities were assessed in between both the groups during and after radiotherapy up to six months based on Common Terminology Criteria for Adverse Effects v5.0. p-values were calculated using the unpaired T-test. Results In the cohort of 60 patients with head and neck cancers, 95% were males. Dosimetric parameters of the planning target volume (PTV) were compared but were not found to be significant. In the dosimetry of the organs at risk, a p-value of some structures was found to be significant although the doses received were well within the tolerable limits in both arms. DARS dosimetry V60 and V70 of the inferior constrictor muscle was found to be statistically significant (p=0.01 and 0.008, respectively). V60 and V70 of larynx were also statistically significant (p=0.009 and 0.000, respectively). V70 and D50 of cricopharyngeus were found to be statistically significant (p=0.01 and 0.03, respectively), V30 and V60 for combined pharyngeal constrictor muscles were found to be statistically significant (p=0.02 and 0.01), and lastly, V60 for combined DARS was also significant (p=0.004). Post-treatment 33.3% of patients in the st-IMRT arm required Ryle's tube placement. No grade 4 toxicities were seen in either arm regarding hematological toxicities, acute or chronic radiation-induced toxicities. In site-wise comparison of doses, the p-value was not found to be significant in patients with oropharyngeal and oral cavity carcinomas but was found to be statistically significant in the larynx and hypopharynx subsites. Conclusion The feasibility of achieving dose constraints to the DARS was seen in cases of laryngeal and hypopharyngeal cancers where the constrictor muscles were at a distance from the PTV. Further, the feasibility of achieving dose constraints may be seen in lower-dose prescriptions either in postoperative cases or in low-risk clinical target volume nodal volumes.

De-escalated radiation for human papillomavirus virus-related oropharyngeal cancer: evolving paradigms and future strategies

The incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma has increased dramatically in recent years reaching epidemic-like proportions. Data has emerged not only showing that these cancers are a unique entity with distinct molecular characteristics but that they also have a significantly improved prognosis as a result of their exquisite radiosensitivity compared to their HPV-negative counterparts. This, it has been increasingly suggested that these tumors can be targeted with de-escalated approaches using reduced doses of radiation. The overriding goal of de-escalation is to maintain the high cure and survival rates associated with traditional approaches while reducing the incidence of both short- and long-term toxicity. Although the exact reason for the improved radiosensitivity of HPV-positive oropharyngeal carcinoma is unclear, prospective studies have now been published demonstrating that de-escalated radiation can successfully maintain the high rates of cure and preserve quality of life for appropriately selected patients with this disease. However, these studies have been complicated by such factors as the relatively limited sample sizes, as well as the variability in treatment, inclusion criteria, and follow-up. As the data continues to mature on de-escalation, it is unquestionable that treatment paradigms for this disease will evolve. The ongoing quest to define a standard regimen comprises the subject of this review.

Quality of Life and Patient-Reported Outcomes Following Proton Therapy for Oropharyngeal Carcinoma: A Systematic Review

BACKGROUND

Complex anatomy surrounding the oropharynx makes proton therapy (PT), especially intensity-modulated PT (IMPT), a potentially attractive option due to its ability to reduce the volume of irradiated healthy tissues. Dosimetric improvement may not translate to clinically relevant benefits. As outcome data are emerging, we aimed to evaluate the evidence of the quality of life (QOL) and patient-reported outcomes (PROs) following PT for oropharyngeal carcinoma (OC).

MATERIALS AND METHODS

We searched PubMed and Scopus electronic databases (date: 15 February 2023) to identify original studies on QOL and PROs following PT for OC. We employed a fluid strategy in the search strategy by tracking citations of the initially selected studies. Reports were extracted for information on demographics, main results, and clinical and dose factor correlates. Quality assessment was performed using the NIH's Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. The PRISMA guidelines were followed in the preparation of this report.

RESULTS

Seven reports were selected, including one from a recently published paper captured from citation tracking. Five compared PT and photon-based therapy, although none were randomized controlled trials. Most endpoints with significant differences favored PT, including xerostomia, cough, need for nutritional supplements, dysgeusia, food taste, appetite, and general symptoms. However, some endpoints favored photon-based therapy (sexual symptoms) or showed no significant difference (e.g., fatigue, pain, sleep, mouth sores). The PROs and QOL improve following PT but do not appear to return to baseline.

CONCLUSION

Evidence suggests that PT causes less QOL and PRO deterioration than photon-based therapy. Biases due to the non-randomized study design remain obstacles to a firm conclusion. Whether or not PT is cost-effective should be the subject of further investigation.

Quality of Life Impacts Following Surgery for Advanced Head and Neck Cancer

Background

Understanding the impact of surgery on patients will enable clinicians to provide evidence-based perioperative management. This study aimed to investigate the quality of life (QoL) impacts following head and neck surgery for advanced stage head and neck cancer.

Methods

Head and neck cancer survivors were invited to complete five validated questionnaires to investigate QoL. Associations between QoL and patient variables were analyzed. Variables included age, time since operation, length of surgery, length of stay, Comorbidity Index, estimated 10-year survival, sex, flap type, treatment and cancer type. Outcome measures were also compared to normative outcomes.

Results

The majority of participants (N = 27; 55% male; mean (standard deviation) age: 62.6 (13.8) years; mean time since operation: 801 days) had a squamous cell carcinoma (88.9%) and free flap repair (100%). Time since operation was significantly (P < 0.05) associated with higher rates of depression (r = -0.533), psychological needs (r = -0.0415) and physical/daily living needs (r = -0.527). Length of surgery and length of stay were significantly associated with depression (r = 0.442; r = 0.435) and length of stay was significantly associated with speaking difficulties (r = -0.456). There was a significant association between work and education scores with age (r = 0.471), length of surgery (r = 0.424), Comorbidity Index (r = 0.456) and estimated 10-year survival (r = -0.523).

Conclusions

Age, time since operation, length of surgery, length of stay, Comorbidity Index and estimated 10-year survival were the outcomes associated with QoL. Patient-reported outcome measures and psychological support could be included in the standard care pathway for head and neck cancer patients to ensure holistic management of their condition.

Impact of dosimetric factors on long-term percutaneous enteral gastrostomy (PEG) tube dependence in head and neck cancer patients after (chemo)radiotherapy-results from a prospective randomized trial

Purpose/objective

To analyze dose–volume histogram (DVH)-derived data on the exposure of organs at risk with impact on long-term percutaneous enteral gastrostomy (PEG) tube dependence in head and neck cancer patients at 6 and 12 months after definitive or adjuvant (chemo)radiotherapy.

Materials and methods

Sixty-one patients were prospectively treated with (chemo)radiotherapy. Prophylactic or reactive gastrostomy tube placement was performed in 41 (67.2%) patients. Dose–volume histogram parameters were obtained for the swallowing apparatus.

Results

Median follow-up time was 25 (2–34) months. Overall survival was shorter in patients with inlying PEG tubes at 6 and 12 months (log rank p = 0.038 and p = 0.017) after therapy completion. The estimated median time of tube dependency was 6 (95% confidence interval: 2–14) months. After 6 months, 46.5% of patients were tube dependent. After 12 months, this estimated proportion fell to 31.5%. For both time points, the volume to the larynx (in %) receiving at least 50 Gy (larynx V50Gy) exceeding 53% was predictive for long-term tube feeding (6 months: p = 0.041 and 12 months: p = 0.042) being an independent predictor during multivariable analysis. There was no clinical feature influencing tube dependence after 12 months.

Conclusion

Long-term gastrostomy dependence was found to be strongly associated with an exposure of laryngeal structures (specifically, V50Gy ≥ 53%) during radiotherapy. Consequently, the avoidance of supraglottic as well as glottic structures is warranted.

Assessment of gene expressions from squamous cell carcinoma of the head and neck to predict radiochemotherapy-related xerostomia and dysphagia

PURPOSE

We tested the hypothesis that gene expressions from biopsies of locally advanced head and neck squamous cell carcinoma (HNSCC) patients can supplement dose-volume parameters to predict dysphagia and xerostomia following primary radiochemotherapy (RCTx).

MATERIAL AND METHODS

A panel of 178 genes previously related to radiochemosensitivity of HNSCC was considered for nanoString analysis based on tumour biopsies of 90 patients with locally advanced HNSCC treated by primary RCTx. Dose-volume parameters were extracted from the parotid, submandibular glands, oral cavity, larynx, buccal mucosa, and lips. Normal tissue complication probability (NTCP) models were developed for acute, late, and for the improvement of xerostomia grade ≥2 and dysphagia grade ≥3 using a cross-validation-based least absolute shrinkage and selection operator (LASSO) approach combined with stepwise logistic regression for feature selection. The final signatures were included in a logistic regression model with optimism correction. Performance was assessed by the area under the receiver operating characteristic curve (AUC).

RESULTS

NTCP models for acute and late xerostomia and the improvement of dysphagia resulted in optimism-corrected AUC values of 0.84, 0.76, and 0.70, respectively. The minimum dose to the contralateral parotid was selected for both acute and late xerostomia and the minimum dose to the larynx was selected for dysphagia improvement. For the xerostomia endpoints, the following gene expressions were selected: RPA2 (cellular response to DNA damage), TCF3 (salivary gland cells development), GBE1 (glycogen storage and regulation), and MAPK3 (regulation of cellular processes). No gene expression features were selected for the prediction of dysphagia.

CONCLUSION

This hypothesis-generating study showed the potential of improving NTCP models using gene expression data for HNSCC patients. The presented models require independent validation before potential application in clinical practice.

Reducing target volume in definitive radiotherapy for human papillomavirus-associated tonsil cancer

BACKGROUND

To evaluate the efficacy and safety of reducing target volume in definitive radiotherapy for HPV-associated tonsil cancer.

METHODS

A single-institution cohort of 90 patients with human papillomavirus (HPV)-associated tonsil cancer who received definitive radiotherapy with a 5-mm expansion from the gross tumor volume to clinical target volume between 2008 and 2019 were included. The overlapping volume of initial planning target volume and the recurrent tumor was calculated and categorized as one of three failure types: in-field: ≥95%; marginal-field: 50%-94%; and out-field: <50%.

RESULTS

With a median follow-up of 59.4 months, the 3-year and 5-year local control rates were 94.4% and 92.8%, respectively. A total of seven local failures were identified, of which 4 (4.4%) were in-field, 2 (2.2%) were marginal-field, and 1 (1.1%) was out-field. Grade 3 acute and late toxicities developed in 30 (33.3%) and 5 (5.6%) patients, respectively.

CONCLUSIONS

Reducing target volume could be an alternative option for selected patients with HPV-associated tonsil cancer.

Avoidance of primary site adjuvant radiotherapy following transoral robotic surgery: a cohort study

BACKGROUND

Post-operative radiotherapy (PORT) volumes and dose to target structures likely influence swallowing function and quality of life following transoral robotic surgery (TORS). The aim of this study is to analyse disease control and swallowing outcomes in patients undergoing TORS for oropharyngeal squamous cell carcinoma (OPSCC) to determine the impact of omitting the primary site from the PORT treatment volume.

METHODS

Prospectively collected data from patients that underwent TORS between March 2013 and April 2021 were reviewed. Patients were categorized into three groups: (1) no PORT, (2) PORT to the neck alone or (3) PORT to the primary site and neck. Survival curves were generated according to the Kaplan-Meier method and swallowing was assessed using the Functional Oral Intake Scale, Public Status Scale Head and Neck, MD Anderson Dysphagia Inventory and feeding tube/gastrostomy dependence.

RESULTS

A total of 121 patients underwent TORS, of which 103 met inclusion criteria with a median follow up of 2.6 years. No patients developed local recurrence. The 3-year regional control rates were 90%, 100% and 100% for groups 1, 2 and 3, respectively. Disease-specific survival was 97% over the study period. Patients that received PORT to both the primary site and the neck (group 3) had worse swallowing outcomes at 12 months.

CONCLUSION

Following TORS for OPSCC, avoiding PORT to the primary site, in appropriately selected patients, appears to be oncologically safe and is associated with superior swallowing outcomes.

Functional swallowing outcomes related to radiation exposure to dysphagia and aspiration-related structures in patients with head and neck cancer undergoing definitive and postoperative intensity-modulated radiotherapy

BACKGROUND

The relationship between swallowing outcomes and radiotherapy dose to dysphagia and aspiration-related structures (DARS) may be different following definitive versus postoperative radiotherapy (PORT) for mucosal head and neck cancer (HNC) and has not been well-studied.

METHOD

Patient- and clinician-reported swallowing measures were prospectively collected at six time points from baseline to 24 months postradiotherapy HNC. Radiotherapy plans were retrospectively analyzed to assess dose delivered to DARS. The association between swallowing outcomes and participant demographics, tumor characteristics, and radiotherapy dose in definitive and postoperative treatment cohorts was assessed.

RESULTS

Ninety-three participants who received radiotherapy for HNC were included in the analysis (n = 49 definitive radiotherapy for laryngeal/pharyngeal primary tumors and n = 44 postoperative PORT for predominantly oral cavity/salivary gland tumors). Participants undergoing PORT had lower doses to DARS than those undergoing definitive RT. High dose to the pharyngeal constrictors and base of tongue for definitive RT and the esophageal inlet, supraglottic larynx and cervical esophagus for the PORT group were associated with worse swallowing function.

CONCLUSION

Radiation dose to DARS is associated with post-treatment swallowing outcomes. These dose/outcome relationships may vary between the definitive and postoperative settings.

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.

Early-Stage Glottic Squamous Cell Carcinoma in the Era of Image-Guided Radiotherapy

Early-stage squamous cell cancer (SCC) of the glottis has a good prognosis. Therefore, patients have long survival outcomes and may potentially suffer from late toxicities of radiotherapy. Radiotherapy with a conventional parallel-opposed-pair or anterior-oblique beam arrangements for stage 1 and 2 glottic SCC have field borders that traditionally cover the entire larynx, exposing organs-at-risk (e.g. carotid arteries, contralateral vocal cord, contralateral arytenoid and inferior pharyngeal constrictor muscles) to high radiation doses. The potential long-term risk of cerebrovascular events has attracted much attention to the dose that carotid arteries receive. Swallow and respiratory motion of laryngeal structures has been an important factor that previously limited reduction of the radiation treatment volume. Motion has been evaluated using multiple imaging modalities and this information has been used to calculate PTV margins for generation of more limited target volumes. This review discusses the current literature surrounding dose-effect relationships for various organs-at-risk and the late toxicities that are associated with them. This article also reviews the currently available data and effects of laryngeal motions on dosimetry to the primary target. We also review the current limitations and benefits of a more targeted approach of radiotherapy for early-stage glottic SCCs and the evolution of CT-based IGRT and MR-guided radiotherapy techniques that may facilitate a shift away from a conventional 3D-conformal radiotherapy approach.

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.

Long-term swallowing outcomes of radiotherapy and transoral laser microsurgery for T1 glottic cancer treatment

INTRODUCTION

Both CO2 transoral laser microsurgery (CO2 TOLMS) and radiotherapy (RT) are standard of care in early glottic carcinoma. However, previous studies focus on voice outcomes rather than swallowing outcomes. This study aimed to compare the late post-treatment effects of CO2 TOLMS and RT treatment on swallowing function in T1 glottic carcinoma.

METHODS

Forty patients (20 CO2 TOLMS and 20 RT) with T1 glottic cancer between May 2015 and January 2019 were included. Certain types of foods triggering dysphagia, any difficulties in bolus control, need to clean the throat, the sensation of lumping in the throat, choking, cough and xerostomia were questioned. Also, functional oral intake scale (FOIS), functional outcome swallowing scale (FOSS), Eating Assessment Tool-10 test (EAT-10) and flexible fiberoptic endoscopic examination of swallowing (FEES) findings were assessed.

RESULTS

CO2 TOLMS patients performed significantly better than the RT group regarding penetration and aspiration with 10 and 20 mL water according to the Penetration and Aspiration Scale (P < .05). The mean EAT-10 Score was found 0 in the CO2 TOLMS group, and 3.20 ± 3.24 in the RT group (P < .05) (lower score indicates a better outcome). According to the Yale Pharyngeal Residue Severity Scale for vallecula, there was no statistically significant difference in vallecular residue between the groups (P > .05). A significantly lesser residue in piriform sinus was detected in the CO2 TOLMS group compared to the RT group with 5 mL and 10 mL water, 5 mL and 20 mL honey consistency food and yogurt according to Yale Pharyngeal Residue Severity Scale (P < .05).

CONCLUSION

It is suggested that in the long term, CO2 TOLMS is more advantageous regarding swallowing function in the treatment of T1 glottic cancer.

MRI- and CT-determined changes of dysphagia / aspiration-related structures (DARS) during and after radiotherapy

Purpose

The concept of dysphagia/aspiration-related structures (DARS) was developed against the background of severe late side effects of radiotherapy (RT) for head and neck cancer (HNC). DARS can be delineated on CT scans, but with a better morphological discrimination on magnetic resonance imaging (MRI). Swallowing function was analyzed by use of patient charts and prospective investigations and questionnaires.

Method

Seventeen HNC patients treated with intensity-modulated radiotherapy (IMRT) ± chemotherapy between 5/2012 – 8/2015 were included. Planning CT (computed tomography) scans and MRIs (magnetic resonance imaging) prior, during 40 Gray (Gy) radiotherapy and posttreatment were available and co-registered to delineate DARS. The RT dose of each DARS was calculated. Five patients were investigated posttreatment for swallowing function and assessed by means of various questionnaires for quality of life (QoL), swallowing, and voice function.

Results

By retrospective comparison of DARS volume, a significant change in four of eight DARS was detected over time. Three increased and one diminished. The risk of posttreatment dysphagia rose by every 1Gy above the mean dose (D mean) of RT to DARS. 7.5 was the risk factor for dysphagia in the first 6 months, reducing to 4.7 for months 6-12 posttreatment. For all five patients of the prospective part of swallowing investigations, a function disturbance was detected. These results were in contrast to the self-assessment of patients by questionnaires. There was neither a dose dependency of D mean DARS volume changes over time nor of dysphonia and no correlation between volume changes, dysphagia or dysphonia.

Conclusion

Delineation of DARS on MRI co-registered to planning CT gave the opportunity to differentiate morphology better than by CT alone. Due to the small number of patients with complete MRI scans over time, we failed to detect a dose dependency of DARS and swallowing and voice disorder posttreatment.

Swallowing functional outcomes and nutritional status in head and neck cancer radiotherapy: longitudinal study

Objective

To explore the relationships between swallowing functional outcomes and nutritional status in patients with head and neck cancer undergoing radiotherapy (RT).

Methods

This longitudinal study included 122 patients. Data were collected at three time points: baseline (T1), the third week of RT (T2) and the completion of RT (T3). The Common Terminology Criteria for Adverse Events was used to assess the symptom of dysphagia and other toxicities; the MD Anderson Dysphagia Inventory (MDADI) was used to assess the patient-perceived swallowing functional outcomes; the nutritional status was evaluated by the weight ratio and the Patient-Generated Subjective Global Assessment (PG-SGA). The generalised estimating equation (GEE) was used to measure the correlation of MDADI with the weight ratio or PG-SGA and also to analyse the influential factors of swallowing functional outcomes.

Results

The participants’ acute dysphagia rates were 5.7% at T1, 69.7% at T2 and 77.9% at T3. The swallowing functional outcomes worsen over RT (p<0.001) and were associated with weight ratio (β=0.032, p=0.008) and PG-SGA (β=−0.115, p<0.001). GEE models showed that patients with cancer of the pharynx region, advanced stage, chemoradiotherapy and high RT dose perceived worse swallowing functional outcomes. Oral mucositis, pharynx mucositis and salivary gland inflammation were positively correlated with swallowing functional outcomes, and the pharynx mucositis presented the highest absolute value of β.

Conclusion

The swallowing functional outcomes were negatively correlated with nutritional status. Healthcare professionals should identify early on the population at higher risk and focus on multiple toxicities, especially the management of pharynx mucositis, to improve nutritional status.

Dose Reduction to the Swallowing Apparatus and the Salivary Glands by De-Intensification of Postoperative Radiotherapy in Patients with Head and Neck Cancer: First (Treatment Planning) Results of the Prospective Multicenter DIREKHT Trial

Aim: Evaluating radiotherapy treatment plans of the prospective DIREKHT trial (ClinicalTrials.gov, NCT02528955) investigating de-intensification of radiotherapy in patients with head and neck cancer. Patients and Methods: The first 30 patients from the DIREKHT trial of the leading study centre were included in this analysis. Standard treatment plans and study treatment plans derived from the protocol were calculated for each patient. Sizes of planning target volumes (PTVs) and mean doses to organs at risk were compared using the Student’s t-test with paired samples. Results: Mean PTV3 including primary tumor region and ipsilateral elective neck up to a dose of 50 Gy in the study treatment plans was 662 mL (+/− 165 mL standard deviation (SD)) and therefore significantly smaller than those of the standard treatment plans (1166 mL (+/− 266 mL SD). In the medial and inferior constrictor muscles, cricopharyngeal muscle, glottic and supraglottic laryngeal areas, arytenoid cartilages, contralateral major salivary glands highly significant dose reductions (p < 0.0001) of more than 10 Gy were achieved in study treatment plan compared to standard treatment plan. Conclusion: De-intensification of radiotherapy led to smaller planning target volumes and clinical relevant dose reductions in the swallowing apparatus and in the contralateral salivary glands.