Objective:Radiomics pipelines have been developed to extract novel information from radiological images, which may help in phenotypic profiling of tumours that would correlate to prognosis. Here, we compared two publicly available pipelines for radiomics analyses on head and neck CT and MRI in nasopharynx cancer (NPC).Methods and materials:100 biopsy-proven NPC cases stratified by T- and N-categories were enrolled in this study. Two radiomics pipeline, Moddicom (v. 0.51) and Pyradiomics (v. 2.1.2) were used to extract radiomics features of CT and MRI. Segmentation of primary gross tumour volume was performed using Velocity v. 4.0 by consensus agreement between three radiation oncologists. Intraclass correlation between common features of the two pipelines was analysed by Spearman’s rank correlation. Unsupervised hierarchical clustering was used to determine association between radiomics features and clinical parameters.Results:We observed a high proportion of correlated features in the CT data set, but not for MRI; 76.1% (51 of 67 common between Moddicom and Pyradiomics) of CT features and 28.6% (20 of 70 common) of MRI features were significantly correlated. Of these, 100% were shape-related for both CT and MRI, 100 and 23.5% were first-order-related, 61.9 and 19.0% were texture-related, respectively. This interpipeline heterogeneity affected the downstream clustering with known prognostic clinical parameters of cTN-status and GTVp. Nonetheless, shape features were the most reproducible predictors of clinical parameters among the different radiomics modules.Conclusion:Here, we highlighted significant heterogeneity between two publicly available radiomics pipelines that could affect the downstream association with prognostic clinical factors in NPCAdvances in knowledge:The present study emphasized the broader importance of selecting stable radiomics features for disease phenotyping, and it is necessary prior to any investigation of multicentre imaging datasets to validate the stability of CT-related radiomics features for clinical prognostication.

Background: The exploration of Advanced Practiced Radiation Therapists (APRTs) development in Singapore started in 2011. This study aims to provide an overview of the development of the APRT roles, and to discuss the approaches used to develop and implement these roles in Singapore. Materials and methods: A mixed methods approach was used in the development of the APRT program. A literature review was carried out to define the APRT scope of practice and core responsibilities. A competency and assessment framework were setup to assess the core competency areas. With this framework, a structured 1-year residency training program was developed. Results: The scope of practice and core responsibilities of APRTs were defined with five proposed advanced practice profiles being successfully validated. A competency framework was set up to assess the core competency domains: clinical, technical and professional competencies, research, education and leadership. A 4-point scoring system was developed for the competency assessment based on two criteria; the frequency with which RTTs would demonstrate competency, and the ability of performing the task competently. A 1-year structured APRT residency program was developed and implemented. The programme consisted of structured lectures, and clinical practice-based modules where APRT residents receive structured mentoring under a mentorship program. Conclusion: The APRT program in Singapore employed an evidence-based implementation process that tested the feasibility of a new practice model. Multidisciplinary involvements, mentorship and clinical training were important factors for the success of the APRT program.

Highlights Show concordance in toxicity assessment between Head and Neck Advanced Practice Radiation Therapist (APRT) and Radiation Oncologist (RO) for Nasopharyngeal Carcinoma (NPC) patients. Describe the importance of timely treatment for NPC patients. Underline the important role development of APRT in complementing the RO. Different ways of data analysis to support the concordance study.

PurposeThe purpose of this study was to evaluate the radiotherapy planning feasibility of dose escalation with intensity‐modulated proton therapy (IMPT) to hypoxic tumor regions identified on 18F‐Fluoromisonidazole (FMISO) positron emission tomography and computed tomography (PET‐CT) in NPC.Materials and methodsNine patients with stages T3‐4N0‐3M0 NPC underwent 18F‐FMISO PET‐CT before and during week 3 of radiotherapy. The hypoxic volume (GTVhypo) is automatically generated by applying a subthresholding algorithm within the gross tumor volume (GTV) with a tumor to muscle standardized uptake value (SUV) ratio of 1.3 on the 18F‐FMISO PET‐CT scan. Two proton plans were generated for each patient, a standard plan to 70 Gy and dose escalation plan with upfront boost followed by standard 70GyE plan. The stereotactic boost was planned with single‐field uniform dose optimization using two fields to deliver 10 GyE in two fractions to GTVhypo. The standard plan was generated with IMPT with robust optimization to deliver 70GyE, 60GyE in 33 fractions using simultaneous integrated boost technique. A plan sum was generated for assessment.ResultsEight of nine patients showed tumor hypoxia on the baseline 18F‐FMISO PET‐CT scan. The mean hypoxic tumor volume was 3.9 cm3 (range .9–11.9cm3). The average SUVmax of the hypoxic volume was 2.2 (range 1.44–2.98). All the dose‐volume parameters met the planning objectives for target coverage. Dose escalation was not feasible in three of eight patients as the D0.03cc of temporal lobe was greater than 75GyE.ConclusionsThe utility of boost to the hypoxic volume before standard course of radiotherapy with IMPT is dosimetrically feasible in selected patients. Clinical trials are warranted to determine the clinical outcomes of this approach.

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