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INTRODUCTION/BACKGROUND: Patients receiving treatment for head and neck cancer (HNC) with curative intent, will potentially undergo primary or adjuvant radiation therapy (RT). These patients require supportive management from an extended multi-disciplinary team, to manage the severe toxicities and distress that a course of treatment can bring. A survey was designed to determine if there were changes in the experience of HNC patients attending for radical RT, from the beginning to the end of their treatment course. During the conduct of the survey the COVID-19 pandemic began. As a result cancer services were adapted to keep patients receiving treatment protected from the virus, while continuing to treat their malignant disease. This enabled a comparison of HNC patient experiences pre-pandemic (PP) and during the pandemic (DP). The study aimed to assess the impact of changes in treatment logistics, implemented as a result of the COVID-19 pandemic, on the patient experience, analysing and comparing how well patients understood the information provided to them, their level of distress and anxiety during treatment, and their overall satisfaction with the experience. METHODS: Eligible patients were receiving radical RT for HNC of any sub-site or histological type. Identical, anonymous surveys were distributed to patients at week 1 and the final week of RT. The initial PP questionnaire (distributed December 2019 to 11th March 2020) contained 22 questions with space for free text. The questionnaire was amended DP to include 6 additional COVID-19 related questions (distributed June to November 2020). RESULTS: One hundred and eighty two surveys were returned; 95 (52%) PP and 87 (48%) DP. Patients were moderately distressed from wearing the immobilisation mask towards the end of treatment DP with a statistically significant difference in the final week, median (IQR) values of 1 (0-4) PP and 2 (1-6) DP, p=0.024. Patients reported increased distress by attending daily for treatment by the final week of RT DP, with a PP and DP median of 1 (0-3) and 2 (1-4) respectively, p=0.039. Patients reporting increased levels of distress about attending for RT also reported high levels of anxiety about COVID-19 (r=0.40, p=0.005). COVID-19 anxiety score displayed a weak inverse association with overall treatment satisfaction score (r=-0.28, p=0.008). CONCLUSION: Despite the adapted COVID-19 working practices implemented and the challenges a course of head and neck RT entails, patients reported a positive experience attending for treatment, both PP and DP.
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INTRODUCTION: With no effective treatment for xerostomia, there remains an unmet need to reduce radiation induced toxicity. Measuring physiological changes during RT in salivary glands using DW-MRI may predict which patients are most at risk of severe toxicity. This study evaluated the feasibility of measuring apparent diffusion coefficient (ADC) in the major salivary glands and describes the observed changes in volume and ADC during RT. METHODS: Scans were acquired at baseline (MR_base) and after 10 fractions (MR_rpt). Sequences included T1 post contrast fat saturated (T1PCFS) and DW-MRI (5b values, 0-1000 s/mm2). Ipsilateral and contralateral parotid (iPG/cPG), submandibular (iSMG/cSMG) and sublingual glands (iSLG/cSLG) were delineated on T1PCFS, modified on b0 and copied to the ADC map. RESULTS: 31 patients with intermediate/high risk squamous cell carcinoma (SCC) of the oropharynx were evaluated. On 124 scans, SMG and SLG delineations were successful on all; parotids were fully contoured in 90.7%. Baseline mean ADC were significantly different between each gland type (p < 0.0001). IPG and cPG volume decreased during treatment by 6.7% and 11.2%. ISMG, cSMG, iSLG and cSLG volume increased by 6.9, 0.9, 60.8 and 60.3% respectively. All structures showed an increase in mean_ADC values. For each gland the increase in ADC was statistically significant p < 0.0001. A smaller mean percentage increase in ADC was observed in the group experiencing a higher grade (2 or > ) of toxicity. CONCLUSION: It is feasible to measure volume and ADC of the salivary glands prior to and during RT for HNC. Early data suggests a lower rise in ADC during treatment is associated with more severe late xerostomia.
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OBJECTIVES: The study aimed to assess the suitability of deformable image registration (DIR) software to generate synthetic CT (sCT) scans for dose verification during radiotherapy to the head and neck. Planning and synthetic CT dose volume histograms were compared to evaluate dosimetric changes during the treatment course. METHODS: Eligible patients had locally advanced (stage III, IVa and IVb) oropharyngeal cancer treated with primary radiotherapy. Weekly CBCT images were acquired post treatment at fractions 1, 6, 11, 16, 21 and 26 over a 30 fraction treatment course. Each CBCT was deformed with the planning CT to generate a sCT which was used to calculate the dose at that point in the treatment. A repeat planning CT2 was acquired at fraction 16 and deformed with the fraction 16 CBCT to compare differences between the calculations mid-treatment. RESULTS: 20 patients were evaluated generating 138 synthetic CT sets. The single fraction mean dose to PTV_HR between the synthetic and planning CT did not vary, although dose to 95% of PTV_HR was smaller at week 6 compared to planning (difference 2.0%, 95% CI (0.8 to 3.1), pâ¯=â¯0.0). There was no statistically significant difference in PRV_brainstem or PRV_spinal cord maximum dose, although greater variation using the sCT calculations was reported. The mean dose to structures based on the fraction 16 sCT and CT2 scans were similar. CONCLUSIONS: Synthetic CT provides comparable dose calculations to those of a repeat planning CT; however the limitations of DIR must be understood before it is applied within the clinical setting.