Oral Mucosa Dose Parameters Predicting Grade ≥3 Acute Toxicity in Locally Advanced Nasopharyngeal Carcinoma Patients Treated With Concurrent Intensity-Modulated Radiation Therapy and Chemotherapy: An Independent Validation Study Comparing Oral Cavity versus Mucosal Surface Contouring Techniques

Dosimetric Comparison and Selection Criteria of Intensity-Modulated Proton Therapy and Intensity-Modulated Radiation Therapy for Adaptive Re-Plan in T3-4 Nasopharynx Cancer Patients

BACKGROUND

Proton therapy requires caution when treating patients with targets near neural structures. Intuitive and quantitative guidelines are needed to support decision-making concerning the treatment modality. This study compared dosimetric profiles of intensity-modulated proton therapy (IMPT) and intensity-modulated radiation therapy (IMRT) using helical tomotherapy (HT) for adaptive re-planning in cT3-4 nasopharyngeal cancer (NPCa) patients, aiming to establish criteria for selecting appropriate treatment modalities.

METHODS

HT and IMPT plans were generated for 28 cT3-4 NPCa patients undergoing definitive radiotherapy. Dosimetric comparisons were performed for target coverage and high-priority organs at risk (OARs). The correlation between dosimetric parameters and RT modality selection was analyzed with the target OAR distances.

RESULTS

Target coverages were similar, while IMPT achieved better dose spillage. HT was more favorable for brainstem D1, optic chiasm Dmax, optic nerves Dmax, and p-cord D1. IMPT showed advantages for oral cavity Dmean. Actually, 14 IMPT and 14 HT plans were selected as adaptive plans, with IMPT allocated to most cT3 patients (92.9% vs. 42.9%, p = 0.013). The shortest distances from the target to neural structures were negatively correlated with OAR doses. Receiver operating characteristic curve analyses were carried out to discover the optimal cut-off values of the shortest distances between the target and the OARs (temporal lobes and brainstem), which were 0.75 cm (AUC = 0.908, specificity = 1.00) and 0.85 cm (AUC = 0.857, specificity = 0.929), respectively.

CONCLUSIONS

NPCa patients with cT4 tumor or with the shortest distance between the target and critical neural structures < 0.8 cm were suboptimal candidates for IMPT adaptive re-planning. These criteria may improve resource utilization and clinical outcomes.

Impact of dose volume parameters and clinical characteristics on radiation-induced acute oral mucositis for head and neck cancer patients treated with carbon-ion radiotherapy dose volume outcome analysis

OBJECTIVES

To assess the predictive value of different dosimetric parameters for acute radiation oral mucositis (ROM) in head and neck cancer (HNCs) patients treated with carbon-ion radiotherapy (CIRT).

METHODS

44 patients with HNCs treated with CIRT were evaluated for acute ROM which was defined as severe when the score ≥3 (acute ROM was scored prospectively using the Radiation Therapy Oncology Group (RTOG) score system). Predictive dosimetric factors were identified by using univariate and multivariate analysis.

RESULTS

Male gender, weight loss >5%, and total dose/fractions were related factors to severe ROM. In multivariate analysis, grade ≥3 ROM was significantly related to the Dmax, D10, D15, and D20 (P < 0.05, respectively). As the receiver operating characteristics (ROC) curve shows, the area under the curve (AUC) for D10 was 0.77 (p = 0.003), and the cutoff value was 51.06 Gy (RBE); The AUC for D15 was 0.75 (p = 0.006), and the cutoff value was 42.82 Gy (RBE); The AUC for D20 was 0.74 (p = 0.009), and the cutoff value was 30.45 Gy (RBE); The AUC for Dmax was 0.81 (p < 0.001), and the cutoff value was 69.33 Gy (RBE).

CONCLUSION

Male gender, weight loss, and total dose/fractions were significantly association with ROM. Dmax, D10, D15 and D20 were identified as the most valuable predictor and we suggest a Dmax limit of 69.33 Gy (RBE), D10 limit of 51.06 Gy (RBE), D15 limit of 42.82 Gy (RBE), and D20 limit of 30.45 Gy (RBE) and for oral mucosa.

Predicting severe radiation-induced oral mucositis in head and neck cancer patients using integrated baseline CT radiomic, dosimetry, and clinical features: A machine learning approach

Purpose

To establish the early prediction models of radiation-induced oral mucositis (RIOM) based on baseline CT-based radiomic features (RFs), dosimetric data, and clinical features by machine learning models for head and neck cancer (HNC) patients.

Methods

In this single-center prospective study, 49 HNCs treated with curative intensity modulated radiotherapy (IMRT) were enrolled. Baseline CT images (i.e., CT simulation), dosimetric, and clinical features were collected. RIOM was assessed using CTCAE v.5.0. RFs were extracted from manually-contoured oral mucosa structures. Minimum-redundancy-maximum-relevance (mRMR) method was applied to select the most informative radiomics, dosimetric, and clinical features. Then, binary prediction models were constructed for predicting acute RIOM based on the top mRMR-ranked radiomics, dosimetric, and clinical features alone or in combination, using random forest classifier algorithm. The predictive performance of models was assessed using the area under the receiver operating curve (AUC), accuracy, weighted-average based sensitivity, precision, and F1-measure.

Results

Among extracted features, the top 10 RFs, the top 5 dose-volume features, and the top 5 clinical features were selected using mRMR method. The model exploiting the integrated features (10-radiomics + 5-dosimetric + 5-clinical) achieved the best prediction with AUC, accuracy, sensitivity, precision, and F1-measure values of 91.7 %, 90.0 %, 83.0 % 100.0 %, and 91.0 %, respectively. The model developed using baseline CT RFs alone provided the best performance compared to dose-volume features or clinical features alone, with an AUC of 87.0 %.

Conclusion

Our results suggest that the integration of baseline CT radiomic features with dosimetric and clinical features showed promising potential to improve the performance of machine learning models in early prediction of RIOM. The ultimate goal is to personalize radiotherapy for HNC patients.

Mean Oral Cavity Organ-at-Risk Dose Predicts Opioid Use and Hospitalization during Radiotherapy for Patients with Head and Neck Tumors

BACKGROUND

Approximately 75% of all head and neck cancer patients are treated with radiotherapy (RT). RT to the oral cavity results in acute and late adverse events which can be severe and detrimental to a patient's quality of life and function. The purpose of this study was to explore associations between RT dose to a defined oral cavity organ-at-risk (OAR) avoidance structure, provider- and patient-reported outcomes (PROs), opioid use, and hospitalization.

METHODS

This was a retrospective analysis of prospectively obtained outcomes using multivariable modeling. The study included 196 patients treated with RT involving the oral cavity for a head and neck tumor. A defined oral cavity OAR avoidance structure was used in all patients for RT treatment planning. Validated PROs were collected prospectively. Opioid use and hospitalization were abstracted electronically from medical records.

RESULTS

Multivariable modeling revealed the mean dose to the oral cavity OAR was significantly associated with opioid use (p = 0.0082) and hospitalization (p = 0.0356) during and within 30 days of completing RT.

CONCLUSIONS

The findings of this study may be valuable in RT treatment planning for patients with tumors of the head and neck region to reduce the need for opioid use and hospitalization during treatment.

Scheduling radiotherapy for patients with nasopharyngeal carcinoma in the corresponding time window can reduce radiation-induced oral mucositis: A randomized, prospective study

BACKGROUND

To explore a new method to reduce radiation-induced oral mucositis by scheduling radiotherapy for patients with nasopharyngeal carcinoma (NPC) in the corresponding time window of the cycle of oral mucosal cells.

METHODS

Eighty-two NPC patients were randomly divided into a day group (n = 41) and a night group (n = 41). The radiotherapy was scheduled at noon (11:30-15:30) for the day group, while at night (19:00-23:00) for the night group. Oral mucositis and oral pain were recorded in both groups after each radiotherapy fraction. The short-term efficacy of primary tumor regression, weight loss, and bone marrow suppression was recorded.

RESULTS

The incidence of Grade 2 oral mucositis was 87.8% (36/41) and 63.4% (26/41) in the night group and day group, respectively (p = 0.010). The incidence of Grade 3 oral mucositis was 65.9% (27/41) and 22.0% (9/41) in the night group and day group, respectively (p < 0.001). The mean number of radiotherapy for patients to develop Grade 2 oral mucositis was 15.67 ± 5.05 and 20.92 ± 6.21 in the night group and day group, respectively. The incidence of Grade 2 oral pain was 48.8% (20/41) and 22.0% (9/41) in the night group and day group, respectively (p = 0.011). There were no significant differences in tumor regression, weight loss, and bone marrow suppression between the two groups.

CONCLUSION

By scheduling radiotherapy based on the corresponding time window of the cycle of oral mucosal cells, the severity of oral mucositis in NPC patients was reduced.

Proton therapy and oral mucositis in oral & oropharyngeal cancers: outcomes, dosimetric and NTCP benefit

INTRODUCTION

Radiation-induced oral mucositis (RIOM), is a common, debilitating, acute side effect of radiotherapy for oral cavity (OC) and oropharyngeal (OPx) cancers; technical innovations for reducing it are seldom discussed. Intensity-modulated-proton-therapy (IMPT) has been reported extensively for treating OPx cancers, and less frequently for OC cancers. We aim to quantify the reduction in the likelihood of RIOM in treating these 2 subsites with IMPT compared to Helical Tomotherapy.

MATERIAL AND METHODS

We report acute toxicities and early outcomes of 22 consecutive patients with OC and OPx cancers treated with IMPT, and compare the dosimetry and normal tissue complication probability (NTCP) of ≥ grade 3 mucositis for IMPT and HT.

RESULTS

Twenty two patients, 77% males, 41% elderly and 73% OC subsite, were reviewed. With comparable target coverage, IMPT significantly reduced the mean dose and D32, D39, D45, and D50, for both the oral mucosa (OM) and spared oral mucosa (sOM). With IMPT, there was a 7% absolute and 16.5% relative reduction in NTCP for grade 3 mucositis for OM, compared to HT. IMPT further reduced NTCP for sOM, and the benefit was maintained in OC, OPx subsites and elderly subgroup. Acute toxicities, grade III dermatitis and mucositis, were noted in 50% and 45.5% patients, respectively, while 22.7% patients had grade 3 dysphagia. Compared with published data, the hospital admission rate, median weight loss, feeding tube insertion, unplanned treatment gaps were lower with IMPT. At a median follow-up of 15 months, 81.8% were alive; 72.7%, alive without disease and 9%, alive with disease.

CONCLUSION

The dosimetric benefit of IMPT translates into NTCP reduction for grade 3 mucositis compared to Helical Tomotherapy for OPx and OC cancers and encourages the use of IMPT in their management.

Effect of nutritional status before radiotherapy on radiation-induced acute toxicities in patients with nasopharyngeal carcinoma

BACKGROUND

To investigate the effect of nutritional status on radiation-induced acute toxicities in nasopharyngeal carcinoma (NPC) patients before radiotherapy.

METHODS

Nutritional status of 228 patients with NPC who received intensity-modulated radiotherapy was retrospectively analyzed by modified nutrition index (m-NI). Cumulative grading score of six common acute toxicities were defined as total score for acute toxicities.

RESULTS

M-NI ≤6 is a risk factor for xerostomia (p = 0.016, OR = 0.208, 95% CI 0.058-0.743), oral mucositis (p = 0.016, OR = 0.287, 95% CI 0.104-0.793), dysgeusia (p = 0.001, OR = 0.028, 95% CI 0.004-0.217), and dysphagia (p = 0.015, OR = 0.251, 95% CI 0.083-0.764) as well in patients with NPC. Total score of radiation-induced acute toxicities of patients with malnutrition (13.6 ± 1.7) was significantly higher than that of patients with normal nutrition (12.0 ± 2.4) (t = -5.464, p < 0.001).

CONCLUSIONS

NPC patients with malnutrition before radiotherapy develop more serious dysgeusia, oral mucositis, dysphagia, and xerostomia after intensity-modulated radiotherapy.

Predicting Nomogram for Severe Oral Mucositis in Patients with Nasopharyngeal Carcinoma during Intensity-Modulated Radiation Therapy: A Retrospective Cohort Study

BACKGROUND

Oral mucositis is an acute adverse reaction with high incidence during radiotherapy. Severe oral mucositis can seriously affect patients' quality of life and compliance with radiotherapy. The aim of this study was to identify the risk factors for severe oral mucositis and to develop a nomogram for predicting severe oral mucositis in patients with nasopharyngeal carcinoma.

METHODS

One hundred and ninety patients with nasopharyngeal carcinoma were retrospectively screened in this study. Least absolute shrinkage and selection operator regression and multivariate logistic regression analyses were performed to identify the best predictors of severe oral mucositis. A nomogram was constructed based on the factors. Finally, the discriminative ability of the nomogram was evaluated.

RESULTS

Four independent factors predicting severe oral mucositis were identified: age, N stage, the cycle of induction chemotherapy, and dose-volumetric parameter V40 (%) of oral cavity. The area under the receiver of operating characteristic curve of the nomogram was 0.759 (95% confidence interval: 0.691-0.827).

CONCLUSIONS

A predictive nomogram for severe oral mucositis was established and validated in this study. The nomogram provides a reliable and practical model for clinically predicting the probability of severe oral mucositis in patients with nasopharyngeal carcinoma before intensity-modulated radiation therapy.

Correlation of oral mucosa dose and volume parameters with Grade 3 mucositis, in patients treated with volumetric modulated arc radiotherapy for oropharyngeal cancer?

Background

Oral mucositis is the dose-limiting toxicity of chemoradiation in oropharyngeal cancer patients, which can be minimized by giving constraints to oral mucosa. However, the constraints defined in literature are extrapolated from chemoradiation in head and neck cancers as a whole. This study aims to determine oral mucosa dose-volume parameters that can predict grade ≥ 3 acute oral mucositis in oropharyngeal cancer patients treated with volumetric modulated arc radiotherapy.

Methods

This prospective study was done in 52 patients of locally advanced oropharyngeal cancer treated with Volumetric modulated arc radiotherapy. Dose-volume histogram data were extracted and then acute oral mucosa toxicity was analysed. Receiver operating characteristic analysis and logistic regression were carried out to determine predictive factors for grade ≥ 3 mucositis.

Results

Grade ≥ 3 acute oral mucositis occurred in 57.6% (30/52) patients in the study. V30Gy &gt; 53.35% (P = 0.005) was an independent dosimetric factor related to grade ≥ 3 acute toxicity. In the receiver operating characteristic curve, the area under V30Gy was 0.770 (P = 0.001); the cut-off value of V30 was 46.23% (sensitivity, 0.80; specificity, 0.91).

Conclusions

Dose-volume histogram analysis predicts V30 &gt; 53.35% as independent factors for grade ≥ 3 acute oral mucositis in patients with oropharyngeal cancers treated with Volumetric modulated arc radiotherapy. Studies in future with more patient number can further validate the above results.

Dosimetric comparison between VMAT plans using the fast-rotating O-ring linac with dual-layer stacked MLC and helical tomotherapy for nasopharyngeal carcinoma

BACKGROUND

To compare the dosimetric profiles of volumetric modulated arc therapy (VMAT) plans using the fast-rotating O-ring linac (the Halcyon system) based on a dual-layer stacked multi-leaf collimator and helical tomotherapy (HT) for nasopharyngeal cancer (NPCa).

METHODS

For 30 NPCa patients, three sets of RT plans were generated, under the same policy of contouring and dose constraints: HT plan; Halcyon VMAT plan with two arcs (HL_2arc); and Halcyon VMAT plan with four arcs (HL_4arc), respectively. The intended dose schedule was to deliver 67.2 Gy to the planning gross target volume (P-GTV) and 56.0 Gy to the planning clinical target volume (P-CTV) in 28 fractions using the simultaneously integrated boost concept. Target volumes and organ at risks dose metrics were evaluated for all plans. Normal tissue complication probabilities (NTCP) for esophagus, parotid glands, spinal cord, and brain stem were compared.

RESULTS

The HT plan achieved the best dose homogeneity index for both P_GTV and P_CTV, followed by the HL_4arc and L_2arc plans. No significant difference in the dose conformity index (CI) for P_GTV was observed between the HT plan (0.80) and either the HL_2arc plan (0.79) or the HL_4arc plan (0.83). The HL_4arc plan showed the best CI for P_CTV (0.88), followed by the HL_2arc plan (0.83) and the HT plan (0.80). The HL_4arc plan (median, interquartile rage (Q1, Q3): 25.36 (22.22, 26.89) Gy) showed the lowest D_mean in the parotid glands, followed by the HT (25.88 (23.87, 27.87) Gy) and HL_2arc plans (28.00 (23.24, 33.99) Gy). In the oral cavity (OC) dose comparison, the HT (22.03 (19.79, 24.85) Gy) plan showed the lowest D_mean compared to the HL_2arc (23.96 (20.84, 28.02) Gy) and HL_4arc (24.14 (20.17, 27.53) Gy) plans. Intermediate and low dose regions (40-65% of the prescribed dose) were well fit to the target volume in HL_4arc, compared to the HT and HL_2arc plans. All plans met the dose constraints for the other OARs with sufficient dose margins. The between-group differences in the median NTCP values for the parotid glands and OC were < 3.47% and < 1.7% points, respectively.

CONCLUSIONS

The dosimetric profiles of Halcyon VMAT plans were comparable to that of HT, and HL_4arc showed better dosimetric profiles than HL_2arc for NPCa.

Association between radiation dose to organs at risk and acute patient reported outcome during radiation treatment for head and neck cancers

BACKGROUND

Associations between patient-reported outcomes and dose to organs at risk (OARs) may promote management and guide future investigations.

METHODS

We retrospectively evaluated PROs and OAR dose in head and neck (H&N) cancer.

RESULTS

In 169 patients, we identified weak associations between: "Difficulty swallowing/chewing" and increased mean RT dose to the oral cavity, larynx, pharyngeal constrictor muscles (PCM) and contralateral parotid; "choking/coughing" and larynx mean dose; "problems with mucus in mouth and throat" and oral cavity, contralateral parotid mean dose and parotid V30, contralateral submandibular gland and PCM mean dose; "difficulty with voice/speech" and oral cavity, contralateral parotid, contralateral submandibular gland and larynx mean dose; and "dry mouth" and ipsilateral submandibular gland, oral cavity and PCM mean dose.

CONCLUSION

We identified weak associations between PRO and dose to OARs-these data can guide on treatment management, patient counseling, and serve as a baseline for future investigations.

Do grape and black mulberry molasses have an effect on oral mucositis and quality of life in patients with head and neck cancer?

OBJECTIVE

We aimed to investigate the effect of black mulberry and grape molasses on the prevention and treatment of oral mucositis and quality of life (QoL) in patients with head and neck cancer (HNC).

METHODS

Patients treated for HNC between 2010 and 2018 in our department were divided into three groups (group 1 = control (n = 14), group 2 = grape molasses (n = 40), and group 3 = black mulberry molasses (n = 40)). Oral mucositis, pain scoring, and weight loss were evaluated weekly. The European Organization for Research and Treatment of Cancer (EORTC) General QoL Questionnaire (QLQ-C30) and EORTC Head and Neck Cancer QoL Module (QLQ-HN35) were used to evaluate QoL.

RESULTS

The mean body weight, scores of oral mucositis, and pain were similar among the groups throughout the treatment. Both groups 2 and 3 were associated with improved outcomes for swallowing, opening mouth, and weight loss in the EORTC HN35, and these parameters were not significantly different between groups 2 and 3. Global health score was higher in group 3 at the 6th week of RT compared to that of group 2. Both groups 2 and 3 had improved scores for role functioning, emotional and social functioning, fatigue, appetite loss, and pain throughout the treatment compared to group 1.

CONCLUSIONS

Both grape and black mulberry molasses improved the QoL in HNC patients. No significant difference between black mulberry and grape molasses was found with regard to the healing of oral mucositis.

Nutritional Status and Its Association With Radiation-Induced Oral Mucositis in Patients With Nasopharyngeal Carcinoma During Radiotherapy: A Prospective Study

Background and Aims

Malnutrition is a concern in patients with nasopharyngeal carcinoma (NPC) during chemoradiotherapy (CRT)/radiotherapy (RT), which is considered to be related with radiation–induced oral mucositis (ROM). The study aimed to evaluate the nutritional status of NPC patients during RT and investigate its association with ROM.

Methods

A prospective study was conducted in NPC patients. Patients were divided into three subgroups (mild, moderate, and severe groups) based on the duration of severe ROM (≥ grade 3). Body weight, body mass index (BMI), albumin, prealbumin, NRS2002, and ROM grade were assessed on a weekly basis before and during CRT/RT. The statistical analysis was performed in the overall group and between three subgroups.

Results

A total of 176 patients were included. In the overall group, body weight and BMI kept decreasing since week 1 of RT, and NRS2002 score and ROM grade increased (p < 0.001). NRS2002 score and prealbumin levels were significantly different between each subgroup (p ≤ 0.046). Significant differences were observed in the proportion of patients receiving enteral nutrition, duration of parenteral nutrition, and total calories provided by nutritional support among three subgroups (p = 0.045–0.001).

Conclusions

Malnutrition occurred early in NPC patients and worsened continuously during RT. ROM was strongly associated with nutritional status. Nutritional support should be provided at the start of RT, especially in patients at high-risk of severe ROM.

Predictive Model and Precaution for Oral Mucositis During Chemo-Radiotherapy in Nasopharyngeal Carcinoma Patients

PURPOSE

To explore risk factors for severe acute oral mucositis of nasopharyngeal carcinoma (NPC) patients receiving chemo-radiotherapy, build predictive models and determine preventive measures.

METHODS AND MATERIALS

Two hundred and seventy NPC patients receiving radical chemo-radiotherapy were included. Oral mucosa structure was contoured by oral cavity contour (OCC) and mucosa surface contour (MSC) methods. Oral mucositis during treatment was prospectively evaluated and divided into severe mucositis group (grade ≥ 3) and non-severe mucositis group (grade < 3) according to RTOG Acute Reaction Scoring System. Nineteen clinical features and nineteen dosimetric parameters were included in analysis, least absolute shrinkage and selection operator (LASSO) logistic regression model was used to construct a risk score (RS) system.

RESULTS

Two predictive models were built based on the two delineation methods. MSC based model is more simplified one, it includes body mass index (BMI) classification before radiation, retropharyngeal lymph node (RLN) area irradiation status and MSC V55%, RS = -1.480 + (0.021 × BMI classification before RT) + (0.126 × RLN irradiation) + (0.052 × MSC V55%). The cut-off of MSC based RS is -1.011, with an area under curve (AUC) of 0.737 (95%CI: 0.672-0.801), a specificity of 0.595 and a sensitivity of 0.786. OCC based model involved more variables, RS= -4.805+ (0.152 × BMI classification before RT) + (0.080 × RT Technique) + (0.097 × Concurrent Nimotuzumab) + (0.163 × RLN irradiation) + (0.028 × OCC V15%) + (0.120 × OCC V60%). The cut-off of OCC based RS is -0.950, with an AUC of 0.767 (95%CI: 0.702-0.831), a specificity of 0.602 and a sensitivity of 0.819. Analysis in testing set shown higher AUC of MSC based model than that of OCC based model (AUC: 0.782 vs 0.553). Analysis in entire set shown AUC in these two method-based models were close (AUC: 0.744 vs 0.717).

CONCLUSION

We constructed two risk score predictive models for severe oral mucositis based on clinical features and dosimetric parameters of nasopharyngeal carcinoma patients receiving chemo-radiotherapy. These models might help to discriminate high risk population in clinical practice that susceptible to severe oral mucositis and individualize treatment plan to prevent it.

Development of a Tongue Immobilization Device Using a 3D Printer for Intensity Modulated Radiation Therapy of Nasopharyngeal Cancer Patients

Purpose

This study aimed to reduce radiation doses to the tongue, a patient-specific semi-customized tongue immobilization device (SCTID) was developed using a 3D printer for helical tomotherapy (HT) of nasopharyngeal cancer (NPCa). Dosimetric characteristics and setup stability of the SCTID were compared with those of a standard mouthpiece (SMP).

Materials and Methods

For displacement and robust immobilization of the tongue, the SCTID consists of four parts: upper and lower tooth stoppers, tongue guider, tongue-tip position guide bar, and connectors. With the SCTID and SMP, two sets of planning computed tomography and HT plans were obtained for 10 NPCa patients. Dosimetric and geometric characteristics were compared. Position reproducibility of the tongue with SCTID was evaluated by comparing with planned dose and adaptive accumulated dose of the tongue and base of the tongue based on daily setup mega-voltage computed tomography.

Results

Using the SCTID, the tongue was effectively displaced from the planning target volume compared to the SMP. The median mucosa of the tongue (M-tongue) dose was significantly reduced (20.7 Gy vs. 27.8 Gy). The volumes of the M-tongue receiving a dose of 15 Gy, 30 Gy, and 45 Gy and the volumes of the mucosa of oral cavity and oropharynx (M-OC/OP) receiving a dose of 45 Gy and 60 Gy were significantly lower than using the SMP. No significant differences was observed between the planned dose and the accumulated adaptive dose in any dosimetric characteristics of the tongue and base of tongue.

Conclusion

SCTID can not only reduce the dose to the M-tongue and M-OC/OP dramatically, when compared to SMP, but also provide excellent reproducibility and easy visual verification.

A Dosimetric Comparison of Oral Cavity Sparing in the Unilateral Treatment of Early Stage Tonsil Cancer: IMRT, IMPT, and Tongue-Deviating Oral Stents

Introduction

Tongue-deviating oral stents (TDOS) are commonly used during unilateral neck radiation therapy to reduce unnecessary dose to nontarget oral structures. Their benefit in the setting of highly conformal treatment techniques, however, is not defined. The goal of this study was to investigate the potential benefit of TDOS use on dosimetric parameters in unilateral intensity modulated radiation therapy (IMRT) and intensity modulated proton therapy (IMPT).

Methods

A total of 16 patients with T1-2 tonsil cancer treated at a single institution were selected, of which 8 were simulated/treated with a TDOS and 8 without a TDOS. All received definitive unilateral IMRT to a dose of 66 Gy in 30 fx. IMPT plans were generated for each patient for study purposes and optimized according to standard institutional practice.

Results

For IMRT plans, the presence of a TDOS (vs without) was associated with a significantly lower oral mucosa mean dose (31.4 vs 35.3 Gy; P = .020) and V30 (42.7% vs 57.1%; P = .025). For IMPT plans, the presence of TDOS (vs without) was not associated with any improvement in oral mucosa mean dose (18.3 vs 19.9 Gy; P = .274) or V30 (25.0% vs 26.2%; P = .655). IMPT plans without TDOS compared with IMRT plans with TDOS demonstrated reduced oral mucosa mean dose (P < .001) and V30 (P < .001).

Conclusion

The use of a TDOS for the unilateral treatment of well-lateralized tonsil cancers was associated with oral mucosa sparing for IMRT, but not for IMPT. Moreover, mucosa sparing was improved for IMPT plans without a TDOS compared to IMRT plans with a TDOS.

Comparison between hypo-fractionated dose-escalated volumetric modulated arc therapy and conventional concurrent chemo-radiation in locally advanced head and neck cancer: a pilot study

Objective:

In the treatment of locally advanced head and neck cancer (LA-HNC), both dose escalation and hypo-fractionation can improve tumour control rates with uncertain role of addition of concurrent chemotherapy. We aimed at developing a new radiotherapy protocol for patients not eligible to receive the standard concurrent chemo-radiation therapy (CCRT) with little toxicity profile.

Methods:

A total of 63 LA-HNC patients were randomised to receive either: 70 Gy in 35 fx in 7 weeks concurrently with cisplatin 100 mg/m2 every 3 weeks for 3 doses (Arm A) or 74 Gy in 33 fx in 6·5 weeks (Arm B). Volumetric modulated arc therapy plans were created for both treatment arms. We compared the local control (LC), progression-free survival (PFS), overall survival (OS) and acute and late toxicity between the two arms.

Results:

A total of 33 patients were in Arm A versus 30 patients in Arm B with median follow-up 24·2 months. No significant differences in LC, PFS and OS between the two arms. Complete remission occurred in 54·5 and 63·3% of patients in Arms A and B, respectively. All toxicities were significantly less in Arm B than Arm A.

Conclusion:

Slightly dose-escalated hypo-fractionated regimen is safe and feasible and has comparable efficacy and less acute and late side effects than conventional dose CCRT with avoidance of chemotherapy-related toxicities in LA-HNC patients.

The Effect of Marital Status on Nasopharyngeal Carcinoma Survival: A Surveillance, Epidemiology and End Results Study

Purpose: This study examined the role of marital status on survival outcome of nasopharyngeal carcinoma (NPC) patients using a population-based cancer registry.

Methods: Patients with primary NPC diagnosed between 2004 and 2013 were included using the Surveillance, Epidemiology and End Results program. Patient demographic, clinicopathologic features, management, and survival outcomes were compared according to marital status. Cause-specific survival (CSS, NPC-related death) for marital status was analyzed.

Results: The data of 3018 patients were included, with 61.4%, 11.1%, 21.8, and 5.6% of patients married, divorced (or separated), single, and widowed, respectively. Widowed patients had the highest proportion of elderly age (p < 0.001), were more likely to be female (p < 0.001), and had more well-to-moderately differentiated (p < 0.001) and node-negative disease (p = 0.038). Widowed patients were also less likely to have received radiotherapy and chemotherapy compared with patients of other marital status (p < 0.001). The 5-year CSS was 76.1%, 70.8%, 73.4%, and 59.8% in the married, divorced, single, and widowed groups, respectively (p = 0.001). Marital status was the independent prognostic factor for CSS. Widowed patients had a significantly increased risk of NPC-related death compared with married (hazard ratio [HR] 2.014, 95% confidence interval [CI] 1.477-2.747, p < 0.001), divorced (HR 1.580, 95% CI 1.087-2.295, p = 0.017), and single (HR 2.000, 95% CI 1.402-2.854, p < 0.001) patients. The divorced (p = 0.067) and single (p = 0.949) groups had similar CSS to the married group.

Conclusions: Being widowed was associated with an increased the risk of cancer mortality in NPC compared with being married, divorced, or single.