The trials within cohorts design facilitated efficient patient enrollment and generalizability in oncology setting

Characteristics, consent patterns, and challenges of randomized trials using the Trials within Cohorts (TwiCs) design - A scoping review

OBJECTIVES

Trials within Cohorts (TwiCs) is a pragmatic design approach that may overcome frequent challenges of traditional randomized trials such as slow recruitment, burdensome consent procedures, or limited external validity. This scoping review aims to identify all randomized controlled trials using the TwiCs design and to summarize their design characteristics, ways to obtain informed consent, output, reported challenges and mitigation strategies.

STUDY DESIGN AND SETTING

Systematic search of Medline, Embase, Cochrane, trial registries and citation tracking up to December 2022. TwiCs were defined as randomized trials embedded in a cohort with postrandomization consent for the intervention group and no specific postrandomization consent for the usual care control group. Information from identified TwiCs was extracted in duplicate from protocols, publications, and registry entries. We analyzed the information descriptively and qualitatively to highlight methodological challenges and solutions related to nonuptake of interventions and informed consent procedure.

RESULTS

We identified a total of 46 TwiCs conducted between 2005 and 2022 in 14 different countries by a handful of research groups. The most common medical fields were oncology (11/46; 24%), infectious diseases (8/46; 17%), and mental health (7/46; 15%). A typical TwiCs was investigator-initiated (46/46; 100%), publicly funded (36/46; 78%), and recruited outpatients (27/46; 59%). Excluding eight pilot trials, only 16/38 (42%) TwiCs adjusted their calculated sample size for nonuptake of the intervention, anticipating a median nonuptake of 25% (interquartile range 10%-32%) in the experimental arm. Seventeen TwiCs (45%) planned analyses to adjust effect estimates for nonuptake. Regarding informed consent, we observed three patterns: 1) three separate consents for cohort participation, randomization, and intervention (17/46; 37%); 2) combined consent for cohort participation and randomization and a separate intervention consent (10/46; 22%); and 3) consent only for cohort participation and intervention (randomization consent not mentioned; 19/46; 41%).

CONCLUSION

Existing TwiCs are globally scattered across a few research groups covering a wide range of medical fields and interventions. Despite the potential advantages, the number of TwiCs remains small. The variability in consent procedures and the possibility of substantial nonuptake of the intervention warrants further research to guide the planning, implementation, and analysis of TwiCs.

The effect of physical exercise during radiotherapy on physical performance in patients with head and neck cancer: a trial within cohorts study protocol, the vital study

BACKGROUND

During the last decade, twelve studies have been published investigating physical exercise interventions (PEIs) in patients with head and neck cancer (HNC) during radiotherapy (RT), chemoradiation (CRT) or bioradiation (BRT). These studies showed that these PEIs are safe and feasible. However, only two of these studies were randomised clinical trials (RCTs) with a satisfying sample size. Thereby, there is no cost-effectiveness study related to a PEI during RT, CRT or BRT ((C/B)RT) for patients with HNC. Therefore, the aim of this study is to investigate and compare physical performance, muscle strength, fatigue, quality of life (QoL), body mass index (BMI), nutritional status, physical activity, treatment tolerability, and health care related costs in patients with HNC with and without a 10 week PEI during (C/B)RT.

METHODS

This study, based on a trial within cohorts (TwiCs) design, will contain a prospective cohort of at least 112 patients. Fifty-six patients will randomly be invited for an experimental 10 week PEI. This PEI consists of both resistance and endurance exercises to optimize physical performance, muscle strength, fatigue, QoL, BMI, nutritional status, physical activity, and treatment tolerability of (C/B)RT. Measurements are at baseline, after 12 weeks, 6 months, and at 12 months. Statistical analyses will be performed for intention-to-treat and instrumental variable analysis.

DISCUSSION

This study seeks to investigate physical, QoL, and economic implications of a PEI. With a substantial sample size, this study attempts to strengthen and expand knowledge in HNC care upon PEI during (C/B)RT. In conclusion, this study is dedicated to provide additional evidence for PEI in patients with HNC during (C/B)RT.

TRIAL REGISTRATION

protocol was registered at clinicaltrials.gov with number NCT05988060 on 3 August 2023.

Hyperbaric Oxygen Therapy and Late Local Toxic Effects in Patients With Irradiated Breast Cancer: A Randomized Clinical Trial

Importance

Hyperbaric oxygen therapy (HBOT) is proposed as treatment for late local toxic effects after breast irradiation. Strong evidence of effectiveness is lacking.

Objective

To assess effectiveness of HBOT for late local toxic effects in women who received adjuvant radiotherapy for breast cancer.

Design, Setting, and Participants

This was a hospital-based, pragmatic, 2-arm, randomized clinical trial nested within the prospective UMBRELLA cohort following the trials within cohorts design in the Netherlands. Participants included 189 women with patient-reported moderate or severe breast, chest wall, and/or shoulder pain in combination with mild, moderate, or severe edema, fibrosis, or movement restriction 12 months or longer after breast irradiation. Data analysis was performed from May to September 2023.

Intervention

Receipt of 30 to 40 HBOT sessions over a period of 6 to 8 consecutive weeks.

Main Outcomes and Measures

Breast, chest wall, and/or shoulder pain 6 months postrandomization measured by the European Organization for Research and Treatment of Cancer QLQ-BR23 questionnaire. Secondary end points were patient-reported fibrosis, edema, movement restriction, and overall quality of life. Data were analyzed according to intention-to-treat (ITT) and complier average causal effect (CACE) principles.

Results

Between November 2019 and August 2022, 125 women (median [range] age at randomization, 56 [37-85] years) with late local toxic effects were offered to undergo HBOT (intervention arm), and 61 women (median [range] age at randomization, 60 [36-80] years) were randomized to the control arm. Of those offered HBOT, 31 (25%) accepted and completed treatment. The most common reason for not accepting HBOT was high treatment intensity. In ITT, moderate or severe pain at follow-up was reported by 58 of 115 women (50%) in the intervention arm and 32 of 52 women (62%) in the control arm (odds ratio [OR], 0.63; 95% CI, 0.32-1.23; P = .18). In CACE, the proportion of women reporting moderate or severe pain at follow-up was 32% (10 of 31) among those completing HBOT and 75% (9.7 of 12.9) among control participants expected to complete HBOT if offered (adjusted OR, 0.34; 95% CI, 0.15-0.80; P = .01). In ITT, moderate or severe fibrosis was reported by 35 of 107 (33%) in the intervention arm and 25 of 49 (51%) in the control arm (OR, 0.36; 95% CI, 0.15-0.81; P = .02). There were no significant differences in breast edema, movement restriction, and quality of life between groups in ITT and CACE.

Conclusions and Relevance

In this randomized clinical trial, offering HBOT to women with late local toxic effects was not effective for reducing pain, but was effective for reducing fibrosis. In the subgroup of women who completed HBOT, a significant reduction in pain and fibrosis was observed. A smaller than anticipated proportion of women with late local toxic effects was prepared to undergo HBOT.

Trial Registration

ClinicalTrials.gov Identifier: NCT04193722.

Randomised trials conducted using cohorts: a scoping review

INTRODUCTION

Cohort studies generate and collect longitudinal data for a variety of research purposes. Randomised controlled trials (RCTs) increasingly use cohort studies as data infrastructures to help identify and recruit trial participants and assess outcomes.

OBJECTIVE

To examine the extent, range and nature of research using cohorts for RCTs and describe the varied definitions and conceptual boundaries for RCTs using cohorts.

DESIGN

Scoping review.

DATA SOURCES

Searches were undertaken in January 2021 in MEDLINE (Ovid) and EBM Reviews-Cochrane Methodology Registry (Final issue, third Quarter 2012).

ELIGIBILITY CRITERIA

Reports published between January 2007 and December 2021 of (a) cohorts used or planned to be used, to conduct RCTs, or (b) RCTs which use cohorts to recruit participants and/or collect trial outcomes, or (c) methodological studies discussing the use of cohorts for RCTs.

DATA EXTRACTION AND SYNTHESIS

Data were extracted on the condition being studied, age group, setting, country/continent, intervention(s) and comparators planned or received, unit of randomisation, timing of randomisation, approach to informed consent, study design and terminology.

RESULTS

A total of 175 full-text articles were assessed for eligibility. We identified 61 protocols, 9 descriptions of stand-alone cohorts intended to be used for future RCTs, 39 RCTs using cohorts and 34 methodological papers.The use and scope of this approach is growing. The thematics of study are far-ranging, including population health, oncology, mental and behavioural disorders, and musculoskeletal conditions.Authors reported that this approach can lead to more efficient recruitment, more representative samples, and lessen disappointment bias and crossovers.

CONCLUSION

This review outlines the development of cohorts to conduct RCTs including the range of use and innovative changes and adaptations. Inconsistencies in the use of terminology and concepts are highlighted. Guidance now needs to be developed to support the design and reporting of RCTs conducted using cohorts.

Is it feasible to nest a Trial within a Cohort Study (TwiCS) to evaluate an early years parenting programme? A Born in Bradford's Better Start study protocol

BACKGROUND

Evaluating the effectiveness of early years parenting interventions provides evidence to improve the development and wellbeing of children. This protocol paper describes a study to explore the feasibility of evaluating the Incredible Years Toddler early life intervention programme, which is offered to parents of 1-3-year-olds via the Better Start Bradford programme. The study aims to use a Trial within a Cohort Study (TwiCS) design that randomly selects individuals participating in a cohort to be offered an intervention. The TwiCS information and consent process is person-centred and aims to replicate real-world practice whereby only those who are offered the intervention are given information about the intervention. The cohort is the Born in Bradford's Better Start (BiBBS) cohort, an interventional birth cohort recruiting expectant parents in three areas of Bradford, UK. The study will assess the feasibility of TwiCS procedures, staged consent, and intervention take-up.

METHODS

We will conduct a feasibility TwiCS to test study procedures. We aim to establish the following: (1) whether TwiCS methodology can be implemented to create control and intervention arms, whilst documenting any incidences of contamination within the cohort; (2) whether satisfactory rates of intervention uptake are achieved among participants allocated to the intervention; and (3) whether satisfactory rates of retention of participants in the intervention can be achieved. A Red Amber Green (RAG) rating system has been applied to support the feasibility assessment of each objective: to be rated red (not achieved), amber (partly achieved), and green (achieved). Eligible participants in the BiBBS cohort will be individually randomised 1:1 to the intervention or control arms, with stratification by child age (1 or 2 years old at the time of randomisation) and ethnicity (White British, South Asian, or other). BiBBS researchers will seek consent from participants randomised to the intervention to pass their contact details onto Incredible Years' delivery agents.

DISCUSSION

This feasibility study will inform the utility of the TwiCs approach within an experimental birth cohort to evaluate interventions for infants, toddlers, and their families.

TRIAL REGISTRATION

The study was prospectively registered on ISRCTN (ISRCTN16150114).

A cohort profile of the Graham Roberts study cohort

Purpose

The Graham Roberts Study was initiated in 2018 and is the first Trials Within Cohorts (TwiCs) study for bladder cancer. Its purpose is to provide an infrastructure for answering a breadth of research questions, including clinical, mechanistic, and supportive care centred questions for bladder cancer patients.

Participants

All consented patients are those aged 18 or older, able to provide signed informedconsent and have a diagnosis of new or recurrent bladder cancer. All patients are required to have completed a series of baseline questionnaires. The questionnaires are then sent out every 12 months and include information on demographics and medical history as well as questionnaires to collect information on quality of life, fatigue, depression, overall health, physical activity, and dietary habits. Clinical information such as tumor stage, grade and treatment has also been extracted for each patient.

Findings to date

To date, a total of 125 bladder cancer patients have been consented onto the study with 106 filling in the baseline questionnaire. The cohort is made up of 75% newly diagnosed bladder cancer patients and 66% non-muscle invasive bladder cancer cases. At present, there is 1-year follow-up information for 70 patients, 2-year follow-up for 57 patients, 3-year follow-up for 47 patients and 4-year follow-up for 19 patients.

Future plans

We plan to continue recruiting further patients into the cohort study. Using the data collected within the study, we hope to carry out independent research studies with a focus on quality of life. We are also committed to utilizing the Roberts Study Cohort to set up and commence an intervention. The future studies and trials carried out using the Roberts Cohort have the potential to identify and develop interventions that could improve the prevention, diagnosis, and treatment of bladder cancer.

Analysis of the characteristics and the degree of pragmatism exhibited by pragmatic-labelled trials of antineoplastic treatments

BACKGROUND

Pragmatic clinical trials (PCTs) are designed to reflect how an investigational treatment would be applied in clinical practice. As such, unlike their explanatory counterparts, they measure therapeutic effectiveness and are capable of generating high-quality real-world evidence. However, the conduct of PCTs remains extremely rare. The scarcity of such studies has contributed to the emergence of the efficacy-effectiveness gap and has led to calls for launching more of them, including in the field of oncology. This analysis aimed to identify self-labelled pragmatic trials of antineoplastic interventions and to evaluate whether their use of this label was justified.

METHODS

We searched PubMed® and Embase® for publications corresponding with studies that investigated antitumor therapies and that were tagged as pragmatic in their titles, abstracts and/or index terms. Subsequently, we consulted all available source documents for the included trials and extracted relevant information from them. The data collected were then used to appraise the degree of pragmatism displayed by the PCTs with the help of the validated PRECIS-2 tool.

RESULTS

The literature search returned 803 unique records, of which 46 were retained upon conclusion of the screening process. This ultimately resulted in the identification of 42 distinct trials that carried the 'pragmatic' label. These studies examined eight different categories of neoplasms and were mostly randomized, open-label, multicentric, single-country trials sponsored by non-commercial parties. On a scale of one (very explanatory) to five (very pragmatic), the median PCT had a PRECIS-2 score per domain of 3.13 (interquartile range: 2.57-3.53). The most and least pragmatic studies in the sample had a score of 4.44 and 1.57, respectively. Only a minority of trials were described in sufficient detail to allow them to be graded across all domains of the PRECIS-2 instrument. Many of the studies examined also had features that arguably precluded them from being pragmatic altogether, such as being monocentric or placebo-controlled in nature.

CONCLUSION

PCTs of antineoplastic treatments are generally no more pragmatic than they are explanatory.

Defining the role of real-world data in cancer clinical research: The position of the European Organisation for Research and Treatment of Cancer

The emergence of the precision medicine paradigm in oncology has led to increasing interest in the integration of real-world data (RWD) into cancer clinical research. As sources of real-world evidence (RWE), such data could potentially help address the uncertainties that surround the adoption of novel anticancer therapies into the clinic following their investigation in clinical trials. At present, RWE-generating studies which investigate antitumour interventions seem to primarily focus on collecting and analysing observational RWD, typically forgoing the use of randomisation despite its methodological benefits. This is appropriate in situations where randomised controlled trials (RCTs) are not feasible and non-randomised RWD analyses can offer valuable insights. Nevertheless, depending on how they are designed, RCTs have the potential to produce strong and actionable RWE themselves. The choice of which methodology to employ for RWD studies should be guided by the nature of the research question they are intended to answer. Here, we attempt to define some of the questions that do not necessarily require the conduct of RCTs. Moreover, we outline the strategy of the European Organisation for Research and Treatment of Cancer (EORTC) to contribute to the generation of robust and high-quality RWE by prioritising the execution of pragmatic trials and studies set up according to the trials-within-cohorts approach. If treatment allocation cannot be left up to random chance due to practical or ethical concerns, the EORTC will consider undertaking observational RWD research based on the target trial principle. New EORTC-sponsored RCTs may also feature concurrent prospective cohorts composed of off-trial patients.

The Trial within Cohorts (TwiCs) study design in oncology: experience and methodological reflections

A Trial within Cohorts (TwiCs) study design is a trial design that uses the infrastructure of an observational cohort study to initiate a randomized trial. Upon cohort enrollment, the participants provide consent for being randomized in future studies without being informed. Once a new treatment is available, eligible cohort participants are randomly assigned to the treatment or standard of care. Patients randomized to the treatment arm are offered the new treatment, which they can choose to refuse. Patients who refuse will receive standard of care instead. Patients randomized to the standard of care arm receive no information about the trial and continue receiving standard of care as part of the cohort study. Standard cohort measures are used for outcome comparisons. The TwiCs study design aims to overcome some issues encountered in standard Randomized Controlled Trials (RCTs). An example of an issue in standard RCTs is the slow patient accrual. A TwiCs study aims to improve this by selecting patients using a cohort and only offering the intervention to patients in the intervention arm. In oncology, the TwiCs study design has gained increasing interest during the last decade. Despite its potential advantages over RCTs, the TwiCs study design has several methodological challenges that need careful consideration when planning a TwiCs study. In this article, we focus on these challenges and reflect on them using experiences from TwiCs studies initiated in oncology. Important methodological challenges that are discussed are the timing of randomization, the issue of non-compliance (refusal) after randomization in the intervention arm, and the definition of the intention-to-treat effect in a TwiCs study and how this effect is related to its counterpart in standard RCTs.

Stereotactic Body radiotherapy and pedicLE screw fixatioN During one hospital visit for patients with symptomatic unstable spinal metastases: a randomized trial (BLEND RCT) using the Trials within Cohorts (TwiCs) design

BACKGROUND

Spinal metastases can lead to unremitting pain and neurological deficits, which substantially impair daily functioning and quality of life. Patients with unstable spinal metastases receive surgical stabilization followed by palliative radiotherapy as soon as wound healing allows. The time between surgery and radiotherapy delays improvement of mobility, radiotherapy-induced pain relief, local tumor control, and restart of systemic oncological therapy. Stereotactic body radiotherapy (SBRT) enables delivery of preoperative high-dose radiotherapy while dose-sparing the surgical field, allowing stabilizing surgery within only hours. Patients may experience earlier recovery of mobility, regression of pain, and return to systemic oncological therapy. The BLEND RCT evaluates the effectiveness of SBRT followed by surgery within 24 h for the treatment of symptomatic, unstable spinal metastases.

METHODS

This phase III randomized controlled trial is embedded within the PRospective Evaluation of interventional StudiEs on boNe meTastases (PRESENT) cohort. Patients with symptomatic, unstable spinal metastases requiring stabilizing surgery and radiotherapy will be randomized (1:1). The intervention group (n = 50) will be offered same-day SBRT and surgery, which they can accept or refuse. According to the Trial within Cohorts (TwiCs) design, the control group (n = 50) will not be informed and receive standard treatment (surgery followed by conventional radiotherapy after 1-2 weeks when wound healing allows). Baseline characteristics and outcome measures will be captured within PRESENT. The primary outcome is physical functioning (EORTC-QLQ-C15-PAL) 4 weeks after start of treatment. Secondary endpoints include pain response, time until return to systemic oncological therapy, quality of life, local tumor control, and adverse events up to 3 months post-treatment.

DISCUSSION

The BLEND RCT evaluates the effect of same-day SBRT and stabilizing surgery for the treatment of symptomatic, unstable spinal metastases compared with standard of care. We expect better functional outcomes, faster pain relief, and continuation of systemic oncological therapy. The TwiCs design enables efficient recruitment within an ongoing cohort, as well as prevention of disappointment bias and drop-out as control patients will not be informed about the trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05575323. Registered on October 11, 2022.

European Groundshot-addressing Europe's cancer research challenges: a Lancet Oncology Commission

Cancer research is a crucial pillar for countries to deliver more affordable, higher quality, and more equitable cancer care. Patients treated in research-active hospitals have better outcomes than patients who are not treated in these settings. However, cancer in Europe is at a crossroads. Cancer was already a leading cause of premature death before the COVID-19 pandemic, and the disastrous effects of the pandemic on early diagnosis and treatment will probably set back cancer outcomes in Europe by almost a decade. Recognising the pivotal importance of research not just to mitigate the pandemic today, but to build better European cancer services and systems for patients tomorrow, the Lancet Oncology European Groundshot Commission on cancer research brings together a wide range of experts, together with detailed new data on cancer research activity across Europe during the past 12 years. We have deployed this knowledge to help inform Europe's Beating Cancer Plan and the EU Cancer Mission, and to set out an evidence-driven, patient-centred cancer research roadmap for Europe. The high-resolution cancer research data we have generated show current activities, captured through different metrics, including by region, disease burden, research domain, and effect on outcomes. We have also included granular data on research collaboration, gender of researchers, and research funding. The inclusion of granular data has facilitated the identification of areas that are perhaps overemphasised in current cancer research in Europe, while also highlighting domains that are underserved. Our detailed data emphasise the need for more information-driven and data-driven cancer research strategies and planning going forward. A particular focus must be on central and eastern Europe, because our findings emphasise the widening gap in cancer research activity, and capacity and outcomes, compared with the rest of Europe. Citizens and patients, no matter where they are, must benefit from advances in cancer research. This Commission also highlights that the narrow focus on discovery science and biopharmaceutical research in Europe needs to be widened to include such areas as prevention and early diagnosis; treatment modalities such as radiotherapy and surgery; and a larger concentration on developing a research and innovation strategy for the 20 million Europeans living beyond a cancer diagnosis. Our data highlight the important role of comprehensive cancer centres in driving the European cancer research agenda. Crucial to a functioning cancer research strategy and its translation into patient benefit is the need for a greater emphasis on health policy and systems research, including implementation science, so that the innovative technological outputs from cancer research have a clear pathway to delivery. This European cancer research Commission has identified 12 key recommendations within a call to action to reimagine cancer research and its implementation in Europe. We hope this call to action will help to achieve our ambitious 70:35 target: 70% average 10-year survival for all European cancer patients by 2035.

Stereotactic ablative radiotherapy or best supportive care in patients with localized pancreatic cancer not receiving chemotherapy and surgery (PANCOSAR): a nationwide multicenter randomized controlled trial according to a TwiCs design

BACKGROUND

Significant comorbidities, advanced age, and a poor performance status prevent surgery and systemic treatment for many patients with localized (non-metastatic) pancreatic ductal adenocarcinoma (PDAC). These patients are currently treated with 'best supportive care'. Therefore, it is desirable to find a treatment option which could improve both disease control and quality of life in these patients. A brief course of high-dose high-precision radiotherapy i.e. stereotactic ablative body radiotherapy (SABR) may be feasible.

METHODS

A nationwide multicenter trial performed within a previously established large prospective cohort (the Dutch Pancreatic cancer project; PACAP) according to the 'Trial within cohorts' (TwiCs) design. Patients enrolled in the PACAP cohort routinely provide informed consent to answer quality of life questionnaires and to be randomized according to the TwiCs design when eligible for a study. Patients with localized PDAC who are unfit for chemotherapy and surgery or those who refrain from these treatments are eligible. Patients will be randomized between SABR (5 fractions of 8 Gy) with 'best supportive care' and 'best supportive care' only. The primary endpoint is overall survival from randomization. Secondary endpoints include preservation of quality of life (EORTC-QLQ-C30 and -PAN26), NRS pain score response and WHO performance scores at baseline, and, 3, 6 and 12 months. Acute and late toxicity will be scored using CTCAE criteria version 5.0: assessed at baseline, day of last fraction, at 3 and 6 weeks, and 3, 6 and 12 months following SABR.

DISCUSSION

The PANCOSAR trial studies the added value of SBRT as compared to 'best supportive care' in patients with localized PDAC who are medically unfit to receive chemotherapy and surgery, or refrain from these treatments. This study will assess whether SABR, in comparison to best supportive care, can relieve or delay tumor-related symptoms, enhance quality of life, and extend survival in these patients.

TRIAL REGISTRATION

Clinical trials, NCT05265663 , Registered March 3 2022, Retrospectively registered.

Physical activity and exercise outcomes in Huntington's disease (PACE-HD): results of a 12-month trial-within-cohort feasibility study of a physical activity intervention in people with Huntington's disease

INTRODUCTION

While physical activity (PA) is recognized as important in Huntington's disease (HD) disease management, there has been no long-term evaluation undertaken. We aimed to evaluate the feasibility of a nested (within cohort) randomized controlled trial (RCT) of a physical therapist-led PA intervention.

METHODS

Participants were recruited from six HD specialist centers participating in the Enroll-HD cohort study in Germany, Spain and U.S. Assessments were completed at baseline and 12 months and linked to Enroll-HD cohort data. Participants at three sites (cohort) received no contact between baseline and 12 month assessments. Participants at three additional sites (RCT) were randomized to PA intervention or control group. The intervention consisted of 18 sessions delivered over 12 months; control group participants received no intervention, however both groups completed monthly exercise/falls diaries and 6-month assessments.

RESULTS

274 participants were screened, 204 met inclusion criteria and 116 were enrolled (59 in cohort; 57 in RCT). Retention rates at 12-months were 84.7% (cohort) and 79.0% (RCT). Data completeness at baseline ranged from 42.3 to 100% and at 12-months 19.2-85.2%. In the RCT, there was 80.5% adherence, high intervention fidelity, and similar adverse events between groups. There were differences in fitness, walking endurance and self-reported PA at 12 months favoring the intervention group, with data completeness >60%. Participants in the cohort had motor and functional decline at rates comparable to previous studies.

CONCLUSION

Predefined progression criteria indicating feasibility were met. PACE-HD lays the groundwork for a future, fully-powered within cohort trial, but approaches to ensure data completeness must be considered.

CLINICALTRIALS

GOV: NCT03344601.

Quality of Life After Stereotactic Body Radiation Therapy Versus Conventional Radiation Therapy in Patients With Bone Metastases

PURPOSE

Painful bone metastases hamper quality of life (QoL). The aim of this prespecified secondary analysis of the PRESENT trial was to compare change in global QoL, physical functioning, emotional functioning, functional interference, and psychosocial aspects after conventional radiation therapy (cRT) versus stereotactic body RT (SBRT).

METHODS AND MATERIALS

A total of 110 patients were enrolled in the phase 2 randomized controlled VERTICAL trial (NCT02364115) following the "trials within cohorts" design and randomized 1:1 to cRT or SBRT. Patient-reported global QoL, physical functioning, emotional functioning, functional interference, and psychosocial aspects were assessed by the European Organization for Research and Treatment of Cancer QoL Questionnaire (QLQ) Core 15 Palliative Care and QLQ Bone Metastases 22 modules. Changes in QoL domains over time were compared between patients treated with cRT and SBRT using intention-to-treat (ITT) and per-protocol (PP) linear mixed model analysis adjusting for baseline scores. Proportions of patients in the cRT versus SBRT arm reporting a clinically relevant change in QoL within 3 months were compared using a χ² test.

RESULTS

QoL scores had improved over time and were comparable between groups for all domains in both the ITT and PP analyses, except for functional interference and psychological aspects in the ITT. Functional interference scores had improved more after 12 weeks in the cRT arm than in the SBRT arm (25.5 vs 14.1 points, respectively; effect size [ES] = 0.49, P = .04). Psychosocial aspects scores had improved more after 8 weeks in the cRT arm than in the SBRT arm (12.2 vs 7.3; ES = 0.56, P = .04). No clinically relevant differences between groups at 12 weeks in terms of global QoL, physical functioning, emotional functioning, functional interference, and psychosocial aspects were observed.

CONCLUSIONS

Palliative RT improves QoL. Both SBRT and cRT have a comparable effect on patient-reported QoL outcomes in patients with painful bone metastases. Functional interference and psychological aspects scores improved more in patients treated with cRT versus patients offered SBRT.

Impact of dose-escalated chemoradiation on quality of life in patients with locally advanced rectal cancer: two year follow-up of the randomized RECTAL-BOOST trial

BACKGROUND

Dose-escalated chemoradiation (CRT) for locally advanced rectal cancer (LARC) did not result in higher complete response rates, but initiated more tumor regression in the randomized XXXXX trial (Clinicaltrials.gov XXXXX). This study compared patient reported outcomes (PROs) between patients who received dose-escalated CRT (5 × 3Gy boost + CRT) or standard CRT for two years following randomization.

METHODS

Patients with LARC, participating in the XXXXX trial, filled out EORTC QLQ-C30 and CR29 questionnaires on quality of life (QoL) and symptoms at baseline, 3, 6, 12, 18 and 24 months following start of treatment. Between-group differences in functional QoL domains were estimated using a linear mixed-effects model and expressed as effect size (ES). Symptom scores were compared using Mann-Whitney U test.

RESULTS

Patients treated with dose-escalated CRT (boost group, n=51) experienced a significantly stronger decline in global health at 3 and 6 months (ES -0,4 and ES -0,4), physical functioning at 6 months (ES -1,1), role functioning at 3 and 6 months (ES -0,8 and ES -0,6) and social functioning at 6 months (ES -0,6) compared to patients treated with standard CRT (control group, n=64). The boost group reported significantly more fatigue at 3 and 6 months (83% vs. 66% resp. 89% vs. 76%), pain at 3 and 6 months (67% vs. 36% resp. 80% vs. 44%) and diarrhea at 3 months (45% vs. 29%) compared to the control group. From 12 months onwards, QoL and symptoms were similar between groups, apart from more blood/mucus in stool in the boost group.

CONCLUSION

In patients with LARC, dose-escalated CRT resulted in a transient deterioration in global health, physical, role, and social functioning and more pain, fatigue and diarrhea at 3 and 6 months following start of treatment compared to standard CRT. From 12 months onwards, the impact of dose-escalated CRT on QoL largely resolved.

Learning healthcare systems and rapid learning in radiation oncology: Where are we and where are we going?

Learning health systems and rapid-learning are well developed at the conceptual level. The promise of rapidly generating and applying evidence where conventional clinical trials would not usually be practical is attractive in principle. The connectivity of modern digital healthcare information systems and the increasing volumes of data accrued through patients' care pathways offer an ideal platform for the concepts. This is particularly true in radiotherapy where modern treatment planning and image guidance offers a precise digital record of the treatment planned and delivered. The vision is of real-world data, accrued by patients during their routine care, being used to drive programmes of continuous clinical improvement as part of standard practice. This vision, however, is not yet a reality in radiotherapy departments. In this article we review the literature to explore why this is not the case, identify barriers to its implementation, and suggest how wider clinical application might be achieved.

Effects of exercise in breast cancer patients: implications of the trials within cohorts (TwiCs) design in the UMBRELLA Fit trial

Purpose

The Trials within Cohorts (TwiCs) design aims to overcome problems faced in conventional RCTs. We evaluated the TwiCs design when estimating the effect of exercise on quality of life (QoL) and fatigue in inactive breast cancer survivors.

Methods

UMBRELLA Fit was conducted within the prospective UMBRELLA breast cancer cohort. Patients provided consent for future randomization at cohort entry. We randomized inactive patients 12–18 months after cohort enrollment. The intervention group (n = 130) was offered a 12-week supervised exercise intervention. The control group (n = 130) was not informed and received usual care. Six-month exercise effects on QoL and fatigue as measured in the cohort were analyzed with intention-to-treat (ITT), instrumental variable (IV), and propensity scores (PS) analyses.

Results

Fifty-two percent (n = 68) of inactive patients accepted the intervention. Physical activity increased in patients in the intervention group, but not in the control group. We found no benefit of exercise for dimensions of QoL (ITT difference global QoL: 0.8, 95% CI = − 2.2; 3.8) and fatigue, except for a small beneficial effect on physical fatigue (ITT difference: − 1.1, 95% CI = − 1.8; − 0.3; IV: − 1.9, 95% CI = − 3.3; − 0.5, PS: − 1.2, 95% CI = − 2.3; − 0.2).

Conclusion

TwiCs gave insight into exercise intervention acceptance: about half of inactive breast cancer survivors accepted the offer and increased physical activity levels. The offer resulted in no improvement on QoL, and a small beneficial effect on physical fatigue.

Trial registration

Netherlands Trial Register (NTR5482/NL.52062.041.15), date of registration: December 07, 2015.

Pain Response After Stereotactic Body Radiation Therapy Versus Conventional Radiation Therapy in Patients With Bone Metastases-A Phase 2 Randomized Controlled Trial Within a Prospective Cohort

PURPOSE

Pain response after conventional external beam radiation therapy (cRT) in patients with painful bone metastases is observed in 60% to 70% of patients. The aim of the VERTICAL trial was to investigate whether stereotactic body radiation therapy (SBRT) improves pain response.

METHODS AND MATERIALS

This single-center, phase 2, randomized controlled trial was conducted within the PRESENT cohort, which consists of patients referred for radiation therapy of bone metastases to our tertiary center. Cohort participants with painful bone metastases who gave broad informed consent for randomization were randomly assigned to cRT or SBRT. Only patients in the intervention arm received information about the trial and were offered SBRT (1 × 18 Gy, 3 × 10 Gy, or 5 × 7 Gy), which they could accept or refuse. Patients who refused SBRT underwent standard cRT (1 × 8 Gy, 5 × 4 Gy, or 10 × 3 Gy). Patients in the control arm were not informed. Primary endpoint was pain response at 3 months after radiation therapy. Secondary outcomes were pain response at any point within 3 months, mean pain scores, and toxicity. Data were analyzed intention to treat (ITT) and per protocol (PP). This trial was registered with Clinicaltrials.gov, NCT02364115.

RESULTS

Between January 29, 2015, and March 20, 2019, 110 patients were randomized. ITT analysis included 44 patients in the cRT arm and 45 patients in the SBRT arm. In the intervention arm, 12 patients (27%) declined SBRT, and 7 patients (16%) were unable to complete the SBRT treatment. In ITT, 14 of 44 patients (32%; 95% confidence interval [CI], 18%-45%) in the control arm and 18 of 45 patients (40%; 95% CI, 26%-54%) in the SBRT arm reported a pain response at 3 months (P = .42). In PP, these proportions were 14 of 44 (32%; 95% CI, 18%-45%) and 12 of 23 patients (46%; 95% CI, 27%-66%), respectively (P = .55). In ITT, a pain response within 3 months was reported by 30 of 44 control patients (82%; 95% CI, 68%-90%) and 38 of 45 patients (84%; 95% CI, 71%-92%) in the SBRT arm (P = .12). In PP, these proportions were 36 of 44 (82%; 95% CI, 68%-90%) and 26 of 27 patients (96%; 95% CI; 81%-100%), respectively (P = .12). No grade 3 or 4 toxicity was observed in either arm.

CONCLUSIONS

SBRT did not significantly improve pain response in patients with painful bone metastases. One in 4 patients preferred to undergo cRT over SBRT, and 1 in 5 patients starting SBRT was unable to complete this treatment. Because of this selective dropout, which can be attributed to the character of the intervention, the trial was underpowered to detect the prespecified difference in pain response.

Circulating tumor DNA guided adjuvant chemotherapy in stage II colon cancer (MEDOCC-CrEATE): study protocol for a trial within a cohort study

BACKGROUND

Accurate detection of patients with minimal residual disease (MRD) after surgery for stage II colon cancer (CC) remains an urgent unmet clinical need to improve selection of patients who might benefit form adjuvant chemotherapy (ACT). Presence of circulating tumor DNA (ctDNA) is indicative for MRD and has high predictive value for recurrent disease. The MEDOCC-CrEATE trial investigates how many stage II CC patients with detectable ctDNA after surgery will accept ACT and whether ACT reduces the risk of recurrence in these patients.

METHODS/DESIGN

MEDOCC-CrEATE follows the 'trial within cohorts' (TwiCs) design. Patients with colorectal cancer (CRC) are included in the Prospective Dutch ColoRectal Cancer cohort (PLCRC) and give informed consent for collection of clinical data, tissue and blood samples, and consent for future randomization. MEDOCC-CrEATE is a subcohort within PLCRC consisting of 1320 stage II CC patients without indication for ACT according to current guidelines, who are randomized 1:1 into an experimental and a control arm. In the experimental arm, post-surgery blood samples and tissue are analyzed for tissue-informed detection of plasma ctDNA, using the PGDx elio™ platform. Patients with detectable ctDNA will be offered ACT consisting of 8 cycles of capecitabine plus oxaliplatin while patients without detectable ctDNA and patients in the control group will standard follow-up according to guideline. The primary endpoint is the proportion of patients receiving ACT when ctDNA is detectable after resection. The main secondary outcome is 2-year recurrence rate (RR), but also includes 5-year RR, disease free survival, overall survival, time to recurrence, quality of life and cost-effectiveness. Data will be analyzed by intention to treat.

DISCUSSION

The MEDOCC-CrEATE trial will provide insight into the willingness of stage II CC patients to be treated with ACT guided by ctDNA biomarker testing and whether ACT will prevent recurrences in a high-risk population. Use of the TwiCs design provides the opportunity to randomize patients before ctDNA measurement, avoiding ethical dilemmas of ctDNA status disclosure in the control group.

TRIAL REGISTRATION

Netherlands Trial Register: NL6281/NTR6455 . Registered 18 May 2017, https://www.trialregister.nl/trial/6281.

Efficacy of Dose-Escalated Chemoradiation on Complete Tumor Response in Patients with Locally Advanced Rectal Cancer (RECTAL-BOOST): A Phase 2 Randomized Controlled Trial

PURPOSE

Pathologic complete tumor response after chemoradiation in patients with locally advanced rectal cancer (LARC) is associated with a favorable prognosis and allows organ-sparing treatment strategies. In the RECTAL-BOOST trial, we aimed to investigate the effect of an external radiation boost to the tumor before chemoradiation on pathologic or sustained clinical complete tumor response in LARC.

METHODS AND MATERIALS

This multicenter, nonblinded, phase 2 randomized controlled trial followed the trials-within-cohorts design, which is a pragmatic trial design allowing cohort participants to be randomized for an experimental intervention. Patients in the intervention group are offered the intervention (and can either accept or refuse this), whereas patients in the control group are not notified about the randomization. Participants of a colorectal cancer cohort referred for chemoradiation of LARC to either of 2 radiation therapy centers were eligible. Patients were randomized to no boost or an external radiation boost (5 × 3 Gy) without concurrent chemotherapy, directly followed by standard pelvic chemoradiation (25 × 2 Gy with concurrent capecitabine). The primary outcome was pathologic complete response (ie, ypT0N0) in patients with planned surgery at 12 weeks, or, as surrogate for pathologic complete response, a 2-year sustained clinical complete response for patients treated with an organ preservation strategy. Analyses were intention to treat. The study was registered with ClinicalTrials.gov, number NCT01951521.

RESULTS

Between September 2014 and July 2018, 128 patients were randomized. Fifty-one of the 64 (79.7%) patients in the intervention group accepted and received a boost. Compared with the control group, fewer patients in the intervention group had a cT4 stage and a low rectal tumor (31.3% vs 17.2% and 56.3% vs 45.3%, respectively), and more patients had a cN2 stage (59.4% vs 70.3%, respectively). Rate of pathologic or sustained clinical complete tumor response was similar between the groups: 23 of 64 (35.9%; 95% confidence interval [CI], 24.3-48.9) in the intervention group versus 24 of 64 (37.5%; 95% CI, 25.7-50.5) in the control group (odds ratio [OR] = 0.94; 95% CI, 0.46-1.92). Near-complete or complete tumor regression was more common in the intervention group (34 of 49; 69.4%) than in the control group (24 of 53; 45.3%; (OR = 2.74, 95% CI 1.21-6.18). Grade ≥3 acute toxicity was comparable: 6 of 64 (9.4%) in the intervention group versus 5 of 64 (7.8%) in the control group (OR = 1.22; 95% CI, 0.35-4.22).

CONCLUSIONS

Dose escalation with an external radiation therapy boost to the tumor before neoadjuvant chemoradiation did not increase the pathologic or sustained clinical complete tumor response rate in LARC.