2024

Simultaneous integrated boost and organ at risk constraints in the APHRODITE trial (2024)

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Type of publication:

Conference abstract

Author(s):

Iddenden J.; Howard D.; Hudson E.; Teo M.; Diez P.; Miles E.; Turtle L.; Patel R.; Appelt A.; *Gollins S.

Citation:

Radiotherapy and Oncology. Conference: ESTRO 2024. Glasgow United Kingdom. 194(Supplement 1) (pp S5977-S5980), 2024. Date of Publication: 01 May 2024.

Abstract:

Purpose/Objective: APHRODITE (ISRCTN16158514), funded by Yorkshire Cancer Research, is a phase II randomised controlled trial comparing radical (chemo)radiotherapy (CRT) alone versus dose-escalated CRT with a simultaneous integrated boost (SIB). Patients with early stage rectal cancer, who are considered by their multidisciplinary team as unsuitable for radical total mesorectum excision or have a strong preference for organ preservation, will all receive 50.4Gy in 28 fractions to a small mesorectal-only planning target volume (PTV). Those in the experimental dose-escalation arm also receive up to 62Gy SIB to the primary tumour volume (PTVp). The trial is currently in active recruitment with a target sample size of 104 patients. Few studies exist detailing dose-volume constraints applied in this setting and none which examine the frequency to which they are achieved1. Anonymised trial plans were retrospectively reviewed to determine if the optimal organ at risk (OAR) dose-volume constraints as set out in the trial protocol are achievable. The conformity of the target volumes coverage was also assessed. Material/Methods: All centres completed the pre-trial radiotherapy quality assurance programme prior to recruiting. Radiotherapy planning data was requested for all patients. To date, 8 centres have recruited patients, with plan data for 46 out of 73 trial patients available at the time of analysis. Radiotherapy was planned according to their randomisation following APHRODITE dose-volume constraints. All plans were retrospectively reviewed on Velocity version 4.1 (Varian Medical Systems, Inc.) and dose-volume constraints extracted from DVH data. Conformity indices, as defined by RTOG (95% isodose volume/volume of PTV), were calculated for all PTVs. The standard deviation was calculated for optimal OAR dose-volume constraints and target volume conformity. Mann-Whitney U tests (two-tailed) were performed to test differences between the standard and dose-escalated arms. Result(s): Dose-volume constraints for the APHRODITE trial were developed from a retrospective mesorectum only planning study for a cohort of early-stage rectal cancer patients2. All constraints were considered optimal, rather than mandatory, due to the paucity of data on normal tissue dose limits in the setting of rectal cancer organ preservation. In all cases, the V95% >= 99% for both PTV and PTVp (dose-escalated arm only) were achieved. Table 1 demonstrates that centres were able to meet the optimal OAR dose-volume constraints in both trial arms in the majority of cases. Randomisation to receive a 62Gy boost did not have a statistically significant impact on achieving optimal OAR dosevolume constraints when compared to the standard arm dose. Evaluation of conformity indices in Table 2 suggested that there was a negligible difference in the conformity of PTV coverage between standard and dose-escalated patients. Mean conformity index for the mesorectal PTV was 1.15 for standard arm patients and 1.16 for patients in the escalated arm (p=0.67). For comparison, mean conformity index for the boost PTVp in the escalated arm was 1.18. The analysis of the target volume conformity test showed that 95% dose conformity is widely achievable across both trial arms in this multi-centre study. Table 2: Conformity indices of target volume and standard deviation Target Volume Mean Conformity Index Standard Deviation Standard (PTV) 1.15 0.06 Escalated (PTV) 1.16 0.05 Escalated (PTVp) 1.18 0.11 Conclusion(s): Delivering a SIB dose of up to 62.0Gy to the primary tumour volume does not have a statistically significant impact on the achievability of optimal OAR dose-volume constraints set out in the APHRODITE trial. Retrospective analysis of available plan data has shown that highly conformal SIB plans can be produced in a multi-centre setting, with resulting dose distributions being comparable to those in the standard arm.

DOI: 10.1016/S0167-8140%2824%2902083-8

Optimisation of the DLG in Mobius3D independent verification software for Ethos and TrueBeam linacs (2025)

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Type of publication:

Conference abstract

Author(s):

*Patel A.; Albaladejo M.M.; Puchades V.P.; Amores D.R.; Arteaga J.S.; Gonzalez A.O.; Berna A.S.

Citation:

Radiotherapy and Oncology. Conference: ESTRO 2024. Glasgow United Kingdom. 194(Supplement 1) (pp S4770-S4773), 2024. Date of Publication: 01 May 2024.

Abstract:

Purpose/Objective: The purpose of this study is to demonstrate the experience in commissioning and optimising Varian's Mobius3D secondary dosimetry software for IMRT/VMAT patient specific QA using Varian TrueBeam HD-MLC and Ethos linacs, performed in the radiotherapy department at Complejo Hospitalario Universitario de Cartagena (CHUC). Material/Methods: Mobius3D provides an independent plan check against the TPS using a separate beam model and dose algorithm. This can be quantified with a 3D gamma pass rate (3%, 3mm threshold at CHUC), as well as point dose differences of seven positions within a Mobius Verification Phantom (MVP), which can be practically verified using a Semiflex 3D ionisation chamber (PTW 31021). For every plan at CHUC, this is initially done in the phantom's central position. Mobius3D was commissioned following Varian's guide for Ethos (energy 6FFF) and TrueBeam (energies 6X and 6FFF) linacs, which included a reference point dose calculation, and verification of the PDD curves, output factors, wedge factors, off-axis ratios, and the CT electron density table. The system was then evaluated against simple conformal plans, followed by more complex clinical VMAT/SBRT/SRS plans. As per the Mobius3D commissioning guidance provided by Varian, if plans are systematically returned with target volumes too hot or too cold with respect to the TPS then it is recommended that the model's dosimetric leaf gap (DLG) correction value is adjusted, which may be different for VMAT and IMRT techniques. For optimisation, Varian recommends using a small ionization chamber within an MVP insert to measure the delivered point dose from 5-10 clinical plans and comparing against the values returned by Mobius3D. This was performed on 8 IMRT plans over a range of DLG correction values. However, as the 3D gamma pass rate metric is generally more often used for comparing dose distributions, it may be more beneficial to optimise against this rather than the point dose difference. This was therefore also performed following the point dose optimisation. Result(s): The results following commissioning from plans on the Ethos linac were promising; for the default DLG values the target volume doses agreed to a sufficient degree, the 3D gamma pass rate (3%, 3mm) had a median of 99.5%, and the point dose difference had a median of -0.1%, as shown in Figure 1 (left and centre) for approximately 200 plans. This was also similar for VMAT plans on the TrueBeam linac. However, the Mobius3D results for IMRT treatments on the TrueBeam model gave target dose distributions which were consistently lower than those provided by the Eclipse TPS (AcurosXB v16). Additionally, the 3D gamma pass rates (3%, 3mm) were below the tolerance of 95%, with a median of 83.1% (n = 21), also shown in Figure 1 (right side). This therefore required optimisation of the DLG values. In this last scenario, the average point-dose difference between the plans was found for each DLG value. A trendline was plotted using linear regression, as depicted in Figure 2, and the DLG corresponding to a 0% point-dose difference was found to be 1.48 +/- 0.05mm. Similarly, the 3D gamma (3%, 3mm) pass rates were also found for each DLG value. Polynomial regression was performed to fit a cubic function to this data, also depicted in Figure 2, which gave a maximum corresponding to a DLG of 1.25 +/- 0.4mm. Considering the results from both methods, the DLG correction on the Mobius3D system for this TrueBeam and both energies was set as the average 1.4mm for IMRT, and 0mm for both VMAT and Ethos. This first value aligns closely with the value used for TrueBeam plans on the Eclipse TPS. From analysing plans following this optimisation, it was observed that the gamma3D (3%, 3mm) pass rates significantly improved, with a new higher median of 96.5% (n = 28, p < 0.001), as shown in Figure 1 (right). Conclusion(s): There is the need to optimize the DLG value for IMRT treatment plans on TrueBeam HD-MLC. Following this adjustment, the Mobius3D software gave satisfactory agreements to the TPS dose distribution for TrueBeam IMRT plans, with a substantial increase in 3D gamma (3%, 3mm) median pass rates. Ethos plans gave strong agreements without the need for optimisation, as did TrueBeam VMAT plans for the software default DLG values. It can therefore be concluded that the Mobius3D software offers a rigorous independent dose check against the TPS and is suitable for clinical use on Ethos and TrueBeam platforms, provided that a proper verification and optimization process has been previously performed.

DOI: 10.1016/S0167-8140%2824%2901289-1

Is Hybrid Closed Loop Continuous Subcutaneous Insulin Infusion Beneficial in Adults with Type 1 Diabetes(T1D) on Continuous Glucose Monitoring: A Reallife District General Hospital Perspective (2024)

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Type of publication:

Conference abstract

Author(s):

*Jones A.; *Basavaraju N.; *Cane C.; *Moulik P.

Citation:

Diabetes Technology and Therapeutics. Conference: Advanced Techologies and Treatments for Diabetes Conference, ATTD 2024. Virtual. 26(Supplement 2) (pp A275-A276), 2024. Date of Publication: 01 Feb 2024.

Abstract:

Background and Aims: Hybrid closed loop(HCL) continuous subcutaneous insulin infusion(CSII) and continuous glucose monitoring(CGM) have made significant improvements in management of T1D.We studied benefits of Hybrid closed loop(HCL) over non-closed loop(NCL) CSII in a cohort of adults with T1D. Method(s): We analysed a live database of patients managed in a single District General Hospital (DGH) service on CSII from 2011 onwards. %Time in range (TIR), %hypoglycaemia (%hypo) and HbA1c were analysed with independent samples T-Test (SPSS software). Result(s): 302 patients were included: mean age was 44 years (range 19-81), female:male 57:43, diabetes duration 25years (range 2-61), and mean pre-CSII HbA1c 63mmol/mol. 218 were on HCL, 21 partial closed loop(PCL) and 63 were NCL. All patients were either on real-time(rt)CGM or intermittently scanned( is)CGM. HCL users were on Medtronic 780G with Guardian G4 sensor or Tandem T-Slim with Dexcom G6 sensor and NCL patients mostly on Omnipod DASH with rtCGM or isCGM. For HCL vs NCL systems, mean HbA1c (52 vs 57mmol/mol, p < 0.005), TIR (71% vs 62%, p < 0.005) were significantly improved on HCL. There was a trend to reduced %hypo (1.64% vs 2.64%,p = 0.08) but not statistically significant. Conclusion(s): This analysis demonstrates significantly better glycaemic control, in both HbA1c and TIR parameters, in HCL CSII users compared to NCL CSII in T1D. Hypoglycaemia was reduced but did not achieve statistical significance, possibly due to overall low rate of hypoglycaemia in the entire cohort. We speculate patients would have been responding to CGM alarm warnings to abort actual hypoglycaemic events.

Is Continuous Glucose Monitoring (CGM) the Critical Technological Intervention in Adults with Type 1 Diabetes(T1D) on Continuous Subcutaneous Insulin Infusion (CSII) Therapy? (2024)

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Type of publication:

Conference abstract

Author(s):

*Jones A.; *Basavaraju N.; *Cane C.; *Kumar A.; *Moulik P.;

Citation:

Diabetes Technology and Therapeutics. Conference: Advanced Techologies and Treatments for Diabetes Conference, ATTD 2024. Virtual. 26(Supplement 2) (pp A230), 2024. Date of Publication: 01 Feb 2024.

Abstract:

Background and Aims: We assessed impact of CGM in existing CSII patients with T1D switching to hybrid closed loop (HCL), partial closed loop (PCL) or remaining on non-closed loop (NCL) CSII. Method(s): Outcomes of patients with T1D on CSII in an adult service from 2011 were reviewed. Analysis of %Time in range (%TIR), %hypoglycaemia (%hypo) and HbA1c was done with SPSS. Result(s): 302 patients were included. 183 were on Tandem T-Slim(T-Slim), 58 Omnipod Dash(DASH), 39 Medtronic780G(780G), 11 Medtronic670G(670G), and 7 Medtronic640G(640G). 218 were on HCL, 21 PCL and 63 NCL. All were on either real-time (rt)CGM (DexcomG6, GuardianG3 or GuardianG4) or intermittently scanned (is)CGM (Freestyle Libre2). T-Slim, DASH, 780G, 670G, 640G showed mean HbA1c of 53.8, 55.6, 53.0, 62, 52.8mmol/mol; %TIR of 70, 64, 72, 61, 56%; and %hypo of 1.7, 1.8, 2.0, 1.4, 4.0% respectively. Post-hoc analysis only showed statistically significant benefits with HbA1c for T-Slim over 670G, and 780G over 670G; %TIR for 780G over 640G and %hypo for T-Slim over 640G. Mean HbA1c and %TIR were significantly better on HCL vs NCL and PCL, but not %hypo. PCL did not show benefit over NCL in HbA1c, %TIR or %hypo. Conclusion(s): We propose CGM confers the most important interventional benefit in patients already on CSII. HCL provided additional benefits in improving glycaemia, both TIR and HbA1c, but not hypo in patients on CGM. PCL does not provide additional benefits over NCL in patients on CGM. QOL indices, however, may show additional benefits both in HCL and PCL.

Does Age Influence Clinical and Patient Satisfaction Outcomes in Adults with Type 1 Diabetes on Continuous Subcutaneous Insulin Infusion (CSII) And Continuous Glucose Monitoring (CGM)? (2024)

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Type of publication:

Conference abstract

Author(s):

*Jones A.; *Basavaraju N.; *Cane C.; *Kumar A.; *Moulik P.

Citation:

Diabetes Technology and Therapeutics. Conference: Advanced Techologies and Treatments for Diabetes Conference, ATTD 2024. Virtual. 26(Supplement 2) (pp A124), 2024. Date of Publication: 01 Feb 2024.

Abstract:

Background and Aims: There is a possibility of subconscious bias towards using complex technology in young adults. Patient perceptions towards treatment may be influenced by age. We explored outcomes and patient experiences in various age groups with Type 1 Diabetes(T1D). Method(s): Database of patients within a single adult pump service was analysed for HbA1c, %time in range(%TIR), %hypoglycaemia(%hypo). Additionally, for Hybrid closed-loop patients Diabetes Treatment Satisfaction Questionnaire (DTSQ), Type 1 Diabetes Distress score(T1DDS), Hypoglycaemia fear survey(HypoFS) and Insulin dosing systems, perceptions, ideas, reflections, and expectations (INSPIRE)scores were analysed in different age groups. Result(s): 302 patients were included: mean age 44 years (range 19-81), 57% females, mean diabetes duration 25years (range 2- 61), and mean pre-CSII HbA1c 63mmol/mol. 218 users had hybrid closed-loop(HCL), 21 partial closed-loop and 63 non-closed-loop CSII. All were on CGM. Only 2 patients were aged above 75years and excluded from statistical analysis. Compared to the entire cohort, 19-25-year-olds had worse mean HbA1c(53.8vs58.8%), TIR(68.7vs59%) and %hypo(1.79vs2.33%), of which only %hypo was not statistically significant. Clinical outcomes were similar in all other groups. Positive Correlation(r) with age was noted with TIR(r = 0.263,p <0.001), DTSQ(r = 0.143, p = 0.03), and negative correlation with %hypo(r = -0.127, p = 0.028), HypoFS(r = -0.309, p <0.001), T1DDS(r = -0.244,p <0.001), and INSPIRE(r = – 0.146,p = 0.038). HypoFS were worse in younger individuals with progressive improvement with increasing age. Conclusion(s): Young adults (19-25 years) had worse clinical outcomes compared to other adults on CSII. Diabetes distress, fear of hypoglycaemia was higher in younger individuals. Use of complex technology including HCL was equally embraced across all age groups, though younger patients may have greater acceptance.

Hybrid-Closed Loop Pump in Type 1 Diabetes (T1D) Improves Clinical Outcome More Than Quality of Life (QoL) Compared to Nonclosed Loop Pumps Supported By CGM (2024)

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Type of publication:

Conference abstract

Author(s):

*Basavaraju N.; *Jones A.; *Cane C.; *Moulik P.

Citation:

Diabetes Technology and Therapeutics. Conference: Advanced Techologies and Treatments for Diabetes Conference, ATTD 2024. Virtual. 26(Supplement 2) (pp A327), 2024. Date of Publication: 01 Feb 2024.

Abstract:

Background and Aims: Hybrid closed loop(HCL) continuous subcutaneous insulin infusion(CSII) and continuous glucose monitoring(CGM) have made significant improvements in management of T1D. We studied benefits of Hybrid closed loop(HCL) over non-closed loop(NCL) CSII in a cohort of adults with T1D. Method(s): We analysed a live database of patients managed in a single centre on CSII. Clinical parameters assessed included %Time in range(TIR), %hypoglycaemia(%hypo) and HbA1c. QOL was assessed with Diabetes Treatment Satisfaction Questionnaire( DTSQ), Hypoglycaemia Fear Survey(HFS), Type 1 Diabetes Distress score(T1DDS). Data was analysed using the SPSS software. Result(s): Data on 281 patients were included, mean age was 44 years(range 19-81), 57% females. 218 were on HCL (Medtronic 780G with Guardian G4 sensor or Tandem T-Slim with Dexcom G6 sensor) and 63 (Omnipod DASH with Dexcom G6 or Freestyle Libre 2). For HCL vs NCL systems, clinical parameters improved with mean HbA1c (52 vs 57mmol/mol, p < 0.005), TIR (71% vs 62%, p < 0.005) and %hypo (1.64% vs 2.64%, p = 0.08). QOL improvement favoured HCL, but were non-significant with mean DTSQ (36.3 vs 35.5, p = 0.21), HFS (33.6vs34.9, p = 0.71) and T1DDS (47.2 vs 49.3, p = 0.40). There was no significant difference in clinical or QOL parameters between Medtronic 780G and Tandem T-Slim HCL systems. Conclusion(s): HCL systems studied had clear benefits in terms of clinical outcome parameters compared to NCL, but this was not reflected in improved patient perceptions on QOL. All patients on NCL being on CGM may be a possible explanation, with the reassurance of CGM making the biggest impact on patients perceived QOL.

Effect of Long Disease Duration on Clinical and Patient Perceived Satisfaction Outcomes in Patients with Type 1 Diabetes (T1DM) on CSII And CGM (2024)

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Type of publication:

Conference abstract

Author(s):

*Jones A.; *Basavaraju N.; *Cane C.; *Moulik P.

Citation:

Diabetes Technology and Therapeutics. Conference: Advanced Techologies and Treatments for Diabetes Conference, ATTD 2024. Virtual. 26(Supplement 2) (pp A326), 2024. Date of Publication: 01 Feb 2024.

Abstract:

Background and Aims: Patients with longstanding T1DM tend to have more glycaemic variability. Patient perceptions towards chronic disease change over time. We examined outcomes in patients on CSII with different DM durations. Method(s): A single adult service outcome database of T1DM patients was analysed for Hba1c, %Time in range(%TIR), %hypoglycaemia(%hypo). For Hybrid closed loop(HCL) patients, Diabetes Treatment satisfaction Questionnaire(DTSQ), Type 1 Diabetes Distress score(T1DDS), Hypoglycaemia fear survey(HypoFS) and Insulin dosing systems, perceptions, ideas, reflections and expectations(INSPIRE) scores were analysed. Results were compared across different disease duration groups. Result(s): A cohort of 302 patients with T1DM were studied. 218 were on HCL, 21 partial closed loop and 63 were nonclosed loop CSII. All were on CGM. Mean diabetes duration was 25 years (range 2-61), male:female 43:57. Mean Hba1c(53.8mmol/mol), %TIR(68.7%) and %hypo(1.79%) were similar except 21-30year duration group who had better Hba1c and TIR. Correlation(r) for Hba1c(r = -0.111,p = 0.055), TIR(r = 0.206, p < 0.001) and %hypo(r = -0.106, p = 0.067) suggest better outcomes with longer duration of diabetes. HypoFS(r = -0.169,p = 0.016) and T1DDS(r = -0.192,p = 0.006) scores correlated inversely, DTSQ(r = 0.148, p = 0.035) positively and INSPIRE(r = -0.127, p = 0.069) did not correlate with diabetes duration. Conclusion(s): CSII and CGM glycaemic outcomes were similar in patients with all diabetes durations, highest in the 20- 30 years duration group. Reasons for this remains uncertain. Longer duration correlated with better outcomes on Hba1c, TIR and satisfaction scores. Hypo fear and diabetes distress was greater with shorter duration though hypo frequency was not statistically correlated to diabetes duration. These may be due to human factors, better disease acceptance and perceptions with longer duration.

Clinical and Patient Satisfaction Outcomes in People with Type 1 Diabetes from Different Social Background Treated with CSII and CGM (2024)

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Type of publication:

Conference abstract

Author(s):

*Jones A.; *Basavaraju N.; *Cane C.; *Moulik P.

Citation:

Diabetes Technology and Therapeutics. Conference: Advanced Techologies and Treatments for Diabetes Conference, ATTD 2024. Virtual. 26(Supplement 2) (pp A326-A327), 2024. Date of Publication: 01 Feb 2024.

Abstract:

Background and Aims: There may be a bias towards use of expensive technological innovations in people from higher socioeconomic classes. We explored patient experiences and outcomes in different socioeconomic backgrounds with T1diabetes( T1DM) treated with insulin pumps. Method(s): Index of Multiple Deprivation (IMD), an official statistic based on income, education, employment, health, housing, crime and living environment was used to stratify patients into quintiles based on socioeconomic status. HbA1c, time in range(%TIR), %hypoglycaemia(%hypo), Diabetes Treatment Satisfaction Questionnaire (DTSQ), Type 1 Diabetes Distress score (T1DDS), Hypoglycaemia fear survey (HypoFS) and Insulin dosing systems, perceptions, ideas, reflections and expectations (INSPIRE) scores in different IMD quintiles were analysed. Result(s): 302 patients were included: mean age 44 years (range 19-81), male:female 43:57 diabetes duration 25years (range 2- 61). 218 were on hybrid closed-loop, 21 partial closed-loop and 63 on non-closed-loop CSII. All were on CGM. Mean HbA1c (53.7vs52.6mmol/mol, correlation r = -0.059,p = 0.3), %TIR (67.7vs70.1%,r = -0.053,p = 0.36) and %hypo (2.29vs1.58%,r = -0.117,p = 0.043) had a trend to be worse in lower socioeconomic classes but correlation was not statistically significant apart from in %hypo. Mean DTSQ and INSPIRE scores were similar between social classes but mean T1DDS (52.8vs41.8,r = -0.189,p = 0.007) and HypoFS (41.7vs29.9,r = -0.145,p = 0.038) scores were worse in lowest compared to highest social quintile. Conclusion(s): Outcomes on CSII and CGM were broadly similar across all social backgrounds. There was statistically significant correlation, albeit low, between lower socioeconomic class and hypoglycaemia. This may explain the higher greater diabetes distress and hypoglycaemia fear in lower socioeconomic classes. Diabetes treatment satisfaction including with HCL were similar.

Deteriorating patient response sticker (2024)

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Type of publication:

Service improvement case study

Author(s):

*Teresa Cole

Citation:

SaTH Improvement Hub, August 2024

SMART Aim:

To improve documented response on deteriorating patients on AMU to (PRH) to 60% to include: investigation plan, treatment plan, escalation plan and review plan by reviewing clinicians by the end of September 2024 using CQUIN data as a baseline for improvement

Link to PDF poster

Quality Governance: Who are we? Step 1 (2024)

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Type of publication:

Service improvement case study

Author(s):

*Gemma Selby

Citation:

SaTH Improvement Hub, September 2024

SMART Aim:

The overall aim is to improve knowledge and understanding of the quality governance team (QGT) role and the impact it has on ED staff and tasks. This poster addressed the process taken to ascertain how best to gain enough responses to the staff questionnaire.

Link to PDF poster