Can patient decision aids reduce decisional conflict in a de-escalation of breast radiotherapy clinical trial? The PRIMETIME Study Within a Trial implemented using a cluster stepped-wedge trial design

BACKGROUND

For patients with early breast cancer considered at very-low risk of local relapse, risks of radiotherapy may outweigh the benefits. Decisions regarding treatment omission can lead to patient uncertainty (decisional conflict), which may be lessened with patient decision aids (PDA). PRIMETIME (ISRCTN 41579286) is a UK-led biomarker-directed study evaluating omission of adjuvant radiotherapy in breast cancer; an embedded Study Within A Trial (SWAT) investigated whether PDA reduces decisional conflict using a cluster stepped-wedge trial design.

METHODS

PDA diagrams and a video explaining risks and benefits of radiotherapy were developed in close collaboration between patient advocates and PRIMETIME trialists. The SWAT used a cluster stepped-wedge trial design, where each cluster represented the radiotherapy centre and referring peripheral centres. All clusters began in the standard information group (patient information and diagrams) and were randomised to cross-over to the enhanced information group (standard information plus video) at 2, 4 or 6 months. Primary endpoint was the decisional conflict scale (0-100, higher scores indicating greater conflict) which was assessed on an individual participant level. Multilevel mixed effects models used a random effect for cluster and a fixed effect for each step to adjust for calendar time and clustering. Robust standard errors were also adjusted for the clustering effect.

RESULTS

Five hundred twenty-one evaluable questionnaires were returned from 809 eligible patients (64%) in 24 clusters between April 2018 and October 2019. Mean decisional conflict scores in the standard group (N = 184) were 10.88 (SD 11.82) and 8.99 (SD 11.82) in the enhanced group (N = 337), with no statistically significant difference [mean difference - 1.78, 95%CI - 3.82-0.25, p = 0.09]. Compliance with patient information and diagrams was high in both groups although in the enhanced group only 121/337 (36%) reported watching the video.

CONCLUSION

The low levels of decisional conflict in PRIMETIME are reassuring and may reflect the high-quality information provision, such that not everyone required the video. This reinforces the importance of working with patients as partners in clinical trials especially in the development of patient-centred information and decision aids.

Abstract P6-12-04: Does the addition of a patient decision aid video reduce decisional conflict in patients considering a de-escalation of radiotherapy trial? Results from the PRIMETIME study

Background: PRIMETIME is a UK-led prospective biomarker-directed cohort study aiming to identify a group of breast cancer patients who can safely avoid radiotherapy following breast conserving surgery. This group is deemed to be at such a low risk of local relapse that the potential benefits of radiotherapy are unlikely to outweigh the risks. The uncertainty patients face regarding healthcare decisions is known as decisional conflict. Patient decision aids (PDA) are interventions which help patients to weigh up the risks and benefits of treatments. Evidence suggests PDA reduce decisional conflict. A study within a trial (SWAT) concept which enables trialists to conduct research embedded within a larger trial was used to investigate if the introduction of a PDA video reduces decisional conflict within PRIMETIME.

Methods: The PDA video was designed to be used in addition to the standard written information and developed in close collaboration with PRIMETIME patient advocates. The PRIMETIME SWAT was implemented using a cluster stepped-wedge trial design. Each cluster was defined as the radiotherapy centre and peripheral centres referring into that centre. All clusters began in the standard information group (receiving written information) and then crossed over to the enhanced information group (receiving written information and PDA video) at either 2, 4 or 6 months. The primary endpoint was a reduction in decisional conflict following PDA implementation. Decisional conflict was assessed using the validated decisional conflict scale questionnaire (0-100 scale with greater scores indicating more decisional conflict) in the standard and enhanced information groups. The target sample size was 288 patients from 24 clusters, to provide 84% power (alpha 0.05) with an effect size of 0.55 (assuming standard deviation, SD=18) across the 0-1 range of possible intra-class correlation values. For the primary endpoint an estimate of the difference in mean decisional conflict pre- and post-implementation of the PDA video was obtained from a multilevel mixed effects linear regression model.

Results: In an interim analysis conducted on 2nd May 2019, 318 evaluable questionnaires were returned from 463 eligible patients (69%) recruited across 24 clusters; 158 questionnaires from the standard and 160 questionnaires from the enhanced group. 60/130 (53%) patients in the enhanced information group (with available data) reportedly did not watch the PDA video.

The mean decisional conflict score in the standard group [158 patients] was 10.73 (SD=11.63) and 8.43 (10.83) in the enhanced group [160 patients]. There was a reduction in decisional conflict in the enhanced compared with the standard group, however the effect size was small and unlikely to be clinically significant [estimated difference in means = -2.50 (-4.73- -0.28), p=0.03, effect size=0.11]. The final analysis will be conducted after the last cluster has crossed over to the enhanced group in October 2019.

Conclusions: A SWAT using a cluster stepped-wedge trial design testing the implementation of a PDA video on patient’s decisional conflict was conducted across multiple UK centres participating in PRIMETIME. The average decisional conflict scores were low therefore there is less scope for obtaining further reductions, and the difference we observed was not clinically significant. The low baseline scores may reflect the PRIMETIME study population who are at low risk of local recurrence. Almost half of patients reportedly did not watch the video; this may be due to the standard written information being sufficient to fulfil the needs of this patient population.

Citation Format: Indrani Subarna Bhattacharya, Joanne Haviland, Ada Balasopoulou, Liba Stones, Hilary Stobart, Lesley Turner, Penelope Hopwood, Charlotte E Coles, Judith M Bliss. Does the addition of a patient decision aid video reduce decisional conflict in patients considering a de-escalation of radiotherapy trial? Results from the PRIMETIME study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-12-04.

Abstract P6-12-10: Method development for a ‘Study within a Trial’ using a cluster stepped wedge trial design: Evaluating a patient decision aid video on patients’ decisional conflict in the PRIMETIME study

Background: PRIMETIME is a UK-led prospective biomarker directed cohort study aiming to identify a group of breast cancer patients who can safely avoid radiotherapy following breast conserving surgery. This group is deemed to be at such a low risk of local relapse that the potential benefits of radiotherapy are unlikely to outweigh the risks. The uncertainty patients face regarding healthcare decisions is known as ‘decisional conflict’ which may increase when a component of standard of care is removed. Patient decision aids (PDA) are interventions which help patients to weigh up the risks and benefits of treatments. Evidence suggests PDA reduce decisional conflict. The study within a trial (SWAT) concept enables trialists to conduct research embedded within a larger trial in an economic and efficient manner. A SWAT testing whether the introduction of a PDA video reduces decisional conflict was conducted within the PRIMETIME study. The method development of the PRIMETIME SWAT is described.

Methods: The SWAT was embedded within PRIMETIME after PRIMETIME had opened to recruitment. All eligible patients approached for the PRIMETIME study were eligible for the PRIMETIME SWAT. The SWAT utilised a cluster stepped-wedge trial design. Each cluster consisted of the radiotherapy centre and any peripheral centres referring into that radiotherapy centre. At the outset of the SWAT, all sites utilised the standard written information when discussing the trial with patients as had been envisaged in the original protocol. At pre-specified time-points each cluster “crossed over” to additionally incorporate the PDA video in the information provided to patients eligible for PRIMETIME. Decisional conflict was assessed in clusters prior to and following implementation of the PDA. The PDA was designed in collaboration with PRIMETIME patient advocates to be used in addition to the standard written information, explaining the same risks and benefits of radiotherapy but using an enhanced video format. Access to the PDA was restricted for healthcare professionals as well as patients until the cluster had crossed over to the intervention group to ensure that healthcare professionals did not alter the way in which they presented the study having watched the video. The primary endpoint was reduction in decisional conflict as measured on the decisional conflict scale.

Discussion: The eligible population for the SWAT was greater than the population of the main PRIMETIME study (i.e. including patients who declined PRIMETIME), to try and obtain a SWAT sample representative of the general population. The cluster aspect of the stepped-wedge design ensured all patients in a cluster would receive uniform information which would simplify processes for sites and avoid cross-contamination between patients. The stepped-wedge aspect enabled all clusters to have access to the PDA by the end of the trial. The PDA was designed to complement the standard written information and explain the risks and benefits of radiotherapy in a different format using a video. If PDA are found to reduce decisional conflict within treatment de-escalation trials, this will provide the evidence to increase resources into the development of PDAs in future trials.

Citation Format: Indrani Subarna Bhattacharya, Joanne S Haviland, Ada Balasopoulou, Liba Stones, Hilary Stobart, Lesley Turner, Penelope Hopwood, Judith M Bliss, Charlotte E Coles. Method development for a ‘Study within a Trial’ using a cluster stepped wedge trial design: Evaluating a patient decision aid video on patients’ decisional conflict in the PRIMETIME study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-12-10.

Clinical Outcome of Prostate Cancer Patients with Germline DNA Repair Mutations: Retrospective Analysis from an International Study

BACKGROUND

Germline DNA damage repair gene mutation (gDDRm) is found in >10% of metastatic prostate cancer (mPC). Their prognostic and predictive impact relating to standard therapies is unclear.

OBJECTIVE

To determine whether gDDRm status impacts benefit from established therapies in mPC.

DESIGN, SETTING, AND PARTICIPANTS

This is a retrospective, international, observational study. Medical records were reviewed for 390 mPC patients with known gDDRm status. All 372 patients from Royal Marsden (UK), Weill-Cornell (NY), and University of Washington (WA) were previously included in a prevalence study (Pritchard, NEJM 2016); the remaining 18 were gBRCA1/2m carriers, from the kConFab consortium, Australia.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Response rate (RR), progression-free survival (PFS), and overall survival (OS) data were collected. To account for potential differences between cohorts, a mixed-effect model (Weibull distribution) with random intercept per cohort was used.

RESULTS AND LIMITATIONS

The gDDRm status was known for all 390 patients (60 carriers of gDDRm [gDDRm+], including 37 gBRCA2m, and 330 cases not found to carry gDDRm [gDDRm-]); 74% and 69% were treated with docetaxel and abiraterone/enzalutamide, respectively, and 36% received PARP inhibitors (PARPi) and/or platinum. Median OS from castration resistance was similar among groups (3.2 vs 3.0 yr, p=0.73). Median docetaxel PFS for gDDRm+ (6.8 mo) was not significantly different from that for gDDRm- (5.1 mo), and RRs were similar (gDDRm+=61%; gDDRm-=54%). There were no significant differences in median PFS and RR on first-line abiraterone/enzalutamide (gDDRm+=8.3 mo, gDDRm-=8.3 mo; gDDRm+=46%, gDDRm-=56%). Interaction test for PARPi/platinum and gDDRm+ resulted in an OS adjusted hazard ratio of 0.59 (95% confidence interval 0.28-1.25; p=0.17). Results are limited by the retrospective nature of the analysis.

CONCLUSIONS

mPC patients with gDDRm appeared to benefit from standard therapies similarly to the overall population; prospective studies are ongoing to investigate the impact of PARPi/platinum.

PATIENT SUMMARY

Patients with inherited DNA repair mutations benefit from standard therapies similarly to other metastatic prostate cancer patients.

Clinical outcome of patients with germline DNA repair mutations: Results from a retrospective international study

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Background: CRPC is enriched for germline mutations in DNA damage repair genes (gDDRm). BRCA2 mutations (g BRCA2m) associate with poor prognosis from localized PC, but prognostic and predictive value for standard therapy in CRPC is unclear. We reviewed clinical outcome of 390 patients previously tested for gDDRm. Methods: Patient records were reviewed for 372 patients from 3 institutions (Royal Marsden UK, Weill-Cornell NY, University of Washington, WA) with gDDRm status previously published (Pritchard et al, NEJM 2016) and 18 g BRCA1/2m carriers from KConFab consortium (Australia). Baseline characteristics and survival were annotated. Response (PSA50%/RECIST) and PFS (RECIST/PSA progression or start of a new therapy due to clinical progression) were collected for Abiraterone, Enzalutamide and Docetaxel. To account for potential differences between cohorts, a mixed effect model (Weibull distribution) with random intercept per cohort was pursued. Results: dDDRm status was available for n = 390 (60 gDDRm+, including 37 g BRCA2m, and 330 gDDRm-). Overall, 74% and 69% received Docetaxel and Abiraterone/Enzalutamide respectively; 47% gDDRm+ and 34% gDDRm- received PARPi and/or platinum. Median overall survival from CRPC was 3.0 vs 3.2 years in gDDRm+ vs gDDRm- (p = 0.73; g BRCA2m = 3.0 years, p = 0.72). Age and Gleason score at diagnosis were associated with survival from castration-resistance in multivariate analysis. Median PFS on Docetaxel for gDDRm+ (6.8 months; 6.3 for g BRCA2m) and gDDRm- (5.1 months) were not significantly different (p = 0.2). Similarly, RR to Docetaxel was similar for the two groups (61% vs 54% in gDDRm+ vs gDDRm-; 63% g BRCA2m). Median PFS and RR on first Abiraterone/Enzalutamide were similar across groups (PFS: 8.3 months gDDRm+, 8.3 months for gDDRm-; p = 0.9; RR 46% vs 56% respectively) The Interaction of PARPi/platinum therapy among gDDRm+ patients resulted in an aHR for OS from CRPC of 0.59 (95%CI 0.28-1.25; p = 0.17). Conclusions: In this retrospective analysis, CRPC patients with gDDRm still benefited from standard therapies similarly to non-mutation carriers; interpretation of survival data should consider the high proportion treated with PARPi/platinum.

Α molecular epidemiological analysis of adenoviruses from excess conjunctivitis cases

BACKGROUND

Τo perform a molecular epidemiological analysis of viral conjunctivitis among excess conjunctivitis cases recorded at the University Hospital of Patras, Greece, for the period March to June 2012.

METHODS

A structured questionnaire containing demographic and clinical data was developed in order to collect retrospective data on the cases. Eye swab specimens were collected and molecular detection of adenoviruses was performed by nested PCR. Positive results were confirmed by sequencing. To determine the relatedness between the isolated sequences, a phylogenetic analysis was conducted.

RESULTS

The epidemiological analysis (including retrospective data) included 231 conjunctivitis cases (47.1% male, and 52.8% female). Based on clinical features 205 of the cases were diagnosed of viral origin (46.3% male and 53.7% female), 4 of bacterial origin (50% male and 50% female) while 22 were undefined conjunctivitis. The outbreak excess cases (included 156 cases) affected all age groups regardless gender predilection. For the positive samples indicated that 29 samples (72.5%) were AdV17, and 5 (12.5%) as AdV54.

CONCLUSIONS

Molecular analysis could define the cause of viral conjunctivitis, while epidemiological data contributed to the assessment of the risk factors and underlined possible preventive measures. This study is one of the very few on viral conjunctivitis in Greece. This outbreak underscores the need for a national surveillance system for acute infectious conjunctivitis outbreaks. The epidemiological as well as molecular investigation on HAdV ocular infections is rather absent in Greece, which has no surveillance system for viral conjunctivitis.

Abstract 4340: DNA repair genes aberrations in germline DNA in metastatic castration-resistant prostate cancer patients

INTRODUCTION: DNA repair defects are found in mCRPC and are therapeutically actionable; germline BRCA mutation-associated (gBRCA) prostate cancer has a poor prognosis. We hypothesized that metastatic castration resistant prostate cancer (mCRPC) is enriched for germline DNA repair mutations and that these may be relevant to patient outcome.

METHODS: Targeted-sequencing for DNA repair genes was conducted in germline DNA from patients consenting to 3 clinical trials between 2013-2015. Germline DNA was extracted from saliva or buccal swabs using the Oragene kit; libraries were constructed using a customized Qiagen panel and sequenced using the Illumina MiSeq. Family history and clinical data were prospectively collected. For time to event analyses unadjusted Cox regression models were used and comparisons were made using log-rank tests.

RESULTS: Germline samples from 154 mCRPC patients were available. Median age at diagnosis was 61years (y), median time to castration-resistance was 14.5 months (m) and median overall survival (OS) from initial diagnosis of prostate cancer was 106.8m; 69% (91/131; 24 N/A) of patients were initially diagnosed with Gleason≥8 tumors. 130/154 (84.4%) and 131/154 (85.0%) received Docetaxel and Abiraterone respectively. Of 154 patients, 4 were previously known to be gBRCA2 mutation carriers and were removed from the prevalence analysis but included in the clinical analyses; 22/150 (14.7%, 95%CI 9.4-21.4%) harboured a truncating or frameshift mutation in a DNA repair gene (9 BRCA2, 6%; 4 ATM, 2.7%; 2 PALB2, 1.3%, 1 each for CHEK2, FANCI, MRE11A, NBN, RAD51C, RAD51D and MSH6). Overall, patients with any germline DNA repair aberrations had a worse median OS (75.8 vs 106.8 m; log-rank p = 0.04). Time to resistance to primary hormonal ablation was shorter specifically for gBRCA2 mutations carriers (11.0 vs 14.8 m; log-rank p = 0.01) but not for non-BRCA2 repair aberrations. Age at diagnosis was similar in patients with or without DNA repair germline mutations (median 61.3 vs 61.7y, Mann-Whitney p = 0.41) as well as frequency of Gleason≥8 tumors (16/21 [76%] vs 75/109 [68%]; Mann-Whitney p = 0.23) Response rates to Docetaxel (14/18 [77.8%] vs 64/94 [68.1%]; Fisher exact p = 0.67) and Abiraterone (10/21 [47.6%] vs 44/94 [46.8%]; Fisher exact p = 0.73) were similar among individuals with and without mutations. Family cancer history was collected in 125/154 cases (81%). While having cases of ovarian/prostate/breast/pancreas cancers in these patients’ families associated with a higher likelihood of finding a germline mutation (Odds Ratio 3.36, p = 0.03), 5 of 68 (7.4%) men with no cases of ovarian/prostate/breast/pancreas cancers registered in their families carried a germline mutation in a DNA repair gene.

CONCLUSIONS: mCRPC is enriched for patients with germline mutations in DNA repair genes (15%), with 6% having gBRCA2 mutation. Germline DNA repair aberrations are associated with a worse prognosis from mCRPC.

Citation Format: JOAQUIN MATEO, Suzanne Carreira, Helen Mossop, Pasquale Rescigno, Michael Kolinsky, Elena Castro, Ada Balasopoulou, Jo Hunt, Desamparados Roda, Claudia Bertan, Jane Goodall, Susana Miranda, Penny Flohr, Nuria Porta, Zsofia Kote-Jarai, David Olmos, Christopher J. Lord, Emma Hall, Ros Eeles, Johann S. de Bono. DNA repair genes aberrations in germline DNA in metastatic castration-resistant prostate cancer patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4340.