Oncology patients were found to understand and accept the Trials within Cohorts design.

BACKGROUND AND OBJECTIVE: The Trials within Cohorts design aims to reduce recruitment difficulties and disappointment bias in pragmatic trials. On cohort enrollment, broad informed consent for randomization is asked, after which cohort participants can be randomized to interventions or serve as controls without further notification. We evaluated patients' recollection, understanding, and acceptance of broad consent in a clinical oncology setting. METHODS: We surveyed 610 patients with cancer participating in ongoing TwiCs; 482 patients (79%) responded, of which 312 patients shortly after cohort enrollment, 108 patients after randomization to an intervention (12-18 months after cohort enrollment), and a random sample of 62 cohort participants who had not been selected for interventions (1-6 months after cohort enrollment). RESULTS: Shortly after providing cohort consent, 76% of patients (238/312) adequately remembered whether they had given broad consent for randomization. Of patients randomly offered interventions, 76% (82/108) remembered giving broad consent for randomization; 41% (44/108) understood they were randomly selected, 44% (48/108) were not interested in selection procedures, and 10% (11/108) did not understand selection was random. Among patients not selected for interventions, 42% (26/62) understood selection was random; 89% felt neutral regarding the scenario of "not being selected for an intervention while your data were being used in comparison with patients receiving interventions," 10% felt reassured (6/62) and 2% scared/insecure (2/62). CONCLUSION: Patients adequately remember giving broad consent for randomization shortly after cohort enrollment and after being offered an intervention, but recollection is lower in those never selected for interventions. Patients are acceptant of serving as control without further notifications.

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.

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

OBJECTIVES: The trials within cohorts (TwiCs) design aims to improve recruitment efficiency. We conducted the first TwiCs in radiation oncology and described efficiency of the design and generalizability of the results. STUDY DESIGN AND SETTING: In two radiotherapy centers, patients with rectal cancer were asked to participate in a prospective cohort study and to provide broad consent for randomization and patient-reported outcomes (PROs). Consenting patients who met the trial criteria were randomized directly after cohort enrollment. The intervention arm was offered a radiotherapy boost. We evaluated acceptance rate, its impact on sample size, and compared clinical characteristics between trial participants and patients of the Dutch national cancer registry. RESULTS: 128 of the 200 eligible patients (64%) were randomized. Sixty-two patients did not consent (in time) to cohort participation, to broad randomization, or to PROs. Of the 64 patients in the intervention arm, 52 (81%) accepted the intervention. During the trial, the acceptance rate dropped temporarily, after which sample size was adapted. Trial patients were comparable in age, comorbidity, and disease stage to the national rectal cancer population. CONCLUSIONS: The TwiCs design is feasible, allows enrollment of a high proportion of randomizable patients, with positive impact on trial efficiency and generalizability of results in a clinical oncology setting.

Health-related quality of life in rectal cancer patients undergoing neoadjuvant chemoradiation with delayed surgery versus short-course radiotherapy with immediate surgery: a propensity score-matched cohort study.

BACKGROUND: Neoadjuvant chemoradiation with delayed surgery (CRT-DS) and short-course radiotherapy with immediate surgery (SCRT-IS) are two commonly used treatment strategies for rectal cancer. However, the optimal treatment strategy for patients with intermediate-risk rectal cancer remains a discussion. This study compares quality of life (QOL) between SCRT-IS and CRT-DS from diagnosis until 24 months after treatment. METHODS: In a prospective colorectal cancer cohort, rectal cancer patients with clinical stage T2-3N0-2M0 undergoing SCRT-IS or CRT-DS between 2013 and 2017 were identified. QOL was assessed using EORTC-C30 and EORTC-CR29 questionnaires before the start of neoadjuvant treatment (baseline) and at 3, 6, 12, 18 and 24 months after. Patients were 1:1 matched using propensity sore matching. Between- and within-group differences in QOL domains were analyzed with linear mixed-effects models. Symptoms and sexual interest at 12 and 24 months were compared using logistic regression models. RESULTS: 156 of 225 patients (69%) remained after matching. The CRT-DS group reported poorer emotional functioning at 3, 6, 12, 18 and 24 months (mean difference with SCRT-IS: -9.4, -12.1, -7.3, -8.0 and -7.9 respectively), and poorer global health, physical-, role-, social- and cognitive functioning at 6 months (mean difference with SCRT-IS: -9.1, -9.8, -14.0, -9.2 and -12.6, respectively). Besides emotional functioning, all QOL domains were comparable at 12, 18 and 24 months. Within-group changes showed a significant improvement of emotional functioning after baseline in the SCRT-IS group, whereas only a minor improvement was observed in the CRT-DS group. Symptoms and sexual interest in male patients at 12 and 24 months were comparable between the groups. CONCLUSIONS: In rectal cancer patients, CRT-DS may induce a stronger decline in short-term QOL than SCRT-IS. From 12 months onwards, QOL domains, symptoms and sexual interest in male patients were comparable between the groups. However, emotional functioning remained higher after SCRT-IS than after CRT-DS.

MRI-based tumor inter-fraction motion statistics for rectal cancer boost radiotherapy.

BACKGROUND: In patients diagnosed with rectal cancer, dose escalation is currently being investigated in a large number of studies. Since there is little known on gross tumor volume (GTV) inter-fraction motion for rectal cancer, a wide variety in margins is used. Purpose of this study is to quantify GTV inter-fraction motion statistics on different timescales and to give estimates of planning target volume (PTV) margins. MATERIAL AND METHODS: Thirty-two patients, diagnosed with rectal cancer, were included. To investigate motion from week-to-week, 16 patients underwent a pretreatment and five weekly MRIs, prior to a radiotherapy (RT) fraction of the chemoradiotherapy treatment. To investigate motion from day-to-day, the remaining 16 patients underwent five daily MRIs before each fraction in one week of RT. GTV was delineated on all scans according to guidelines. Scans were aligned on bony anatomy with the first MRI. For both datasets separately, GTV inter-fraction motion was determined based on center-of-gravity displacement. Therefrom, systematic and random errors were determined in left/right (LR), anterior/posterior and cranial/caudal (CC) direction. PTV margin estimates were calculated and evaluated on GTV coverage. RESULTS: Systematic and random errors were found in the range of 2.3-4.8 mm and 1.5-3.3 mm from week-to-week, and 1.8-4.5 mm and 1.8-4.0 mm from day-to-day, respectively. On both timescales, similar motion patterns were found; the most motion was observed in CC whilst the least motion was observed in LR. On the week-to-week data more systematic and less random motion was observed compared to the day-to-day data. Overall, only slight differences in margin estimates were found. Derived PTV margin estimates were found to give adequate GTV coverage. CONCLUSION: GTV inter-fraction motion, on a week-to-week and day-to-day timescale, can be accounted for using motion statistics presented in this study.

Does setup on rectal wall improve rectal cancer boost radiotherapy?

BACKGROUND: Rectal cancer patients that show a pathological complete response (pCR) after neo-adjuvant chemo-radiotherapy, have better prognosis. To increase pCR rates several studies escalate the tumor irradiation dose. However, due to lacking tumor contrast on online imaging techniques, no direct tumor setup can be performed and large boost margins are needed to ensure tumor coverage. The purpose of this study was to evaluate the feasibility of performing a setup on rectal wall for rectal cancer boost radiotherapy, thereby using rectal wall nearby the tumor as tumor position surrogate. METHODS: For sixteen patients, daily MRI's were performed during 1 week of radiotherapy. On each of these images, tumor and rectum were delineated. Residual displacements were determined per surface voxel after setup on bony anatomy or nearby rectal wall and setup errors for both setups were compared. Furthermore for every rectal wall voxel nearby the tumor, displacement was compared with the closest tumor point and correlation was determined. RESULTS: Mean (SD) setup error was 2.7 mm (3.3 mm) and 2.2 mm (3.2 mm) after setup on bony anatomy and rectal wall respectively. Nevertheless, similar PTV-margin estimates i.e. 95th percentile distances, were found; 8.0 mm. Also, a merely moderate correlation; ρ = 0.66 was found between rectal wall and tumor displacement. Further investigation into tumor and rectal mobility differences showed that the rectal wall lacks appropriate anatomical landmarks to find true displacements, especially to capture motion along the rectal wall. CONCLUSIONS: Setup on rectal wall slightly reduces mean setup errors but requires a similar PTV-margin as compared to setup on bony anatomy. Rectal mobility might be similar to tumor mobility, but due the absence of anatomical landmarks in the rectum, displacements along the rectal wall are not detected on current online imaging. Therefore, to further reduce tumor position uncertainties, direct or indirect online tumor visualization is needed.

Effect of Neoadjuvant Therapy and Rectal Surgery on Health-related Quality of Life in Patients With Rectal Cancer During the First 2 Years After Diagnosis.

INTRODUCTION: Rectal cancer surgery with neoadjuvant therapy is associated with substantial morbidity. The present study describes the course of quality of life (QOL) in rectal cancer patients in the first 2 years after the start of treatment. PATIENTS AND METHODS: We performed a prospective study within a colorectal cancer cohort including rectal cancer patients who were referred for neoadjuvant chemoradiation or short-course radiotherapy and underwent rectal surgery. QOL was assessed using the European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30) and colorectal cancer questionnaire (EORTC QLQ-CR29) before treatment and after 3, 6, 12, 18, and 24 months. The outcomes were compared with the QOL scores from the Dutch general population and stratified by low anterior resection and abdominoperineal resection. Postoperative bowel dysfunction after low anterior resection was measured using the low anterior resection syndrome score. RESULTS: Of the 324 patients, 272 (84%) responded to at least 2 questionnaires and were included in the present study. Compared with pretreatment levels, the strongest decline was observed in physical, role, and social functioning at 3 and 6 months after the start of treatment. Global health and cognitive functioning declined to a lesser extend, and emotional functioning gradually improved over the time. Within 24 months, the QOL scores had recovered toward the pretreatment levels in most patients. Compared with the general population, physical, role, social, and cognitive functioning and symptoms of fatigue and insomnia remained significantly worse in patients on longer-term. After low anterior resection, major bowel dysfunction was reported by 44% to 60% of the patients. Increasing urinary incontinence and severe complaints of impotence were observed in patients who had undergone abdominoperineal resection. CONCLUSION: Rectal cancer treatment is associated with a significant decline in QOL during the first 6 months after the diagnosis. Within 2 years, most patients return toward pretreatment functioning but could still experience poorer functioning and treatment-related symptoms compared with the general population. These findings support shared decision-making and emphasize the need for postoperative supportive care and novel treatment approaches.

Utility Scores and Preferences for Surgical and Organ-Sparing Approaches for Treatment of Intermediate and High-Risk Rectal Cancer.

BACKGROUND: Organ-sparing approaches, including wait-and-see and local excision, are increasingly being offered to patients with rectal cancer following a good response to neoadjuvant therapy. Preferences regarding these treatment strategies are yet unknown. OBJECTIVE: This study aimed to determine the preferences and utility scores for rectal cancer treatment approaches. DESIGN: This is a cross-sectional study. SETTING: This study was conducted at the Radiation-Oncology Department of the University Medical Center Utrecht. PATIENTS: Fifty-seven patients with a history of rectal cancer and 38 volunteers were included. MAIN OUTCOME MEASURES: Participants assessed 6 hypothetical treatment-outcome scenarios, including short-course radiotherapy or chemoradiation followed by abdominoperineal resection, low anterior resection, local excision, or a wait-and-see approach. The hierarchy in preferences between scenarios was assessed by using ranking. Utilities were estimated with a visual analog scale and time trade-off. RESULTS: Organ-sparing approaches were ranked as the first preferred treatment option by 51% of the participants. Among all scenarios, wait-and-see was most often ranked highest by patients and volunteers (36% and 50%). Meanwhile, a substantial proportion ranked wait-and-see as their lowest preference (38% in patients and 35% in volunteers). Utility scores differed significantly between scenarios. Wait-and-see received a significantly higher score on the visual analog scale than the scenarios including abdominoperineal resection and the scenario including chemoradiation with low anterior resection, and a score similar to the scenarios including local excision and short-course radiotherapy with low anterior resection. LIMITATIONS: The study population consisted of patients with a history of rectal cancer treatment and volunteers related to patients. This may have influenced preferences. CONCLUSIONS: This study suggests that there is a wide disparity in preferences concerning organ-sparing approaches for rectal cancer in both patients with a history of rectal cancer and volunteers. Wait-and-see is often the highest preferred treatment, but it is also among the least preferred treatment options. These findings give insights into how patients may value the current rectal cancer treatment options. See Video Abstract at http://links.lww.com/DCR/A521.

The impact of postoperative complications on health-related quality of life in older patients with rectal cancer; a prospective cohort study.

OBJECTIVES: As result of the aging population and increasing rectal cancer incidence, more older patients undergo treatment for rectal cancer. This study compares treatment course, postoperative complications, and quality of life (QOL) between older and younger patients with rectal cancer and evaluates the impact of postoperative complications on QOL in the elderly. MATERIALS AND METHODS: Patients with rectal cancer participating in a prospective colorectal cancer cohort and referred for radiotherapy between 2013 and 2016 were included. QOL was assessed with the cancer questionnaire of the European Organisation for Research and Treatment of Cancer (EORTC QLQ-C30) before treatment and at three, six, and twelve months. Outcomes were compared between older patients (≥70years) and younger patients (<70years) and stratified by presence of postoperative complications. RESULTS: In total, 115 (33%) older patients and 230 (67%) younger patients were included. Compared to younger patients, older patients underwent significantly more often short-course radiation with delayed surgery (6.1% and 19.1% respectively) and less often chemoradiation (62.6% and 39.1% respectively), and were more likely to undergo a Hartmann procedure with permanent stoma (3.5% and 13.0% respectively) instead of sphincter-sparing surgery (43.9% and 29.6% respectively). Postoperative complication rates were similar (38.5% in older patients versus 34.7% in younger patients). Older patients had worse physical functioning at six and twelve months after diagnosis compared to younger patients. Presence of postoperative complications had a significant stronger impact on physical- and role functioning in older patients. CONCLUSION: Older patients undergo more often a tailored treatment approach for rectal cancer than younger patients. With this tailored approach, similar postoperative complication rates and QOL are achieved. However, postoperative complications have a larger negative impact on physical- and role functioning in older patients which indicates a need for better prediction of postoperative complications in the elderly.

Evolution of motion uncertainty in rectal cancer: implications for adaptive radiotherapy.

Reduction of motion uncertainty by applying adaptive radiotherapy strategies depends largely on the temporal behavior of this motion. To fully optimize adaptive strategies, insight into target motion is needed. The purpose of this study was to analyze stability and evolution in time of motion uncertainty of both the gross tumor volume (GTV) and clinical target volume (CTV) for patients with rectal cancer. We scanned 16 patients daily during one week, on a 1.5 T MRI scanner in treatment position, prior to each radiotherapy fraction. Single slice sagittal cine MRIs were made at the beginning, middle, and end of each scan session, for one minute at 2 Hz temporal resolution. GTV and CTV motion were determined by registering a delineated reference frame to time-points later in time. The 95th percentile of observed motion (dist95%) was taken as a measure of motion. The stability of motion in time was evaluated within each cine-MRI separately. The evolution of motion was investigated between the reference frame and the cine-MRIs of a single scan session and between the reference frame and the cine-MRIs of several days later in the course of treatment. This observed motion was then converted into a PTV-margin estimate. Within a one minute cine-MRI scan, motion was found to be stable and small. Independent of the time-point within the scan session, the average dist95% remains below 3.6 mm and 2.3 mm for CTV and GTV, respectively 90% of the time. We found similar motion over time intervals from 18 min to 4 days. When reducing the time interval from 18 min to 1 min, a large reduction in motion uncertainty is observed. A reduction in motion uncertainty, and thus the PTV-margin estimate, of 71% and 75% for CTV and tumor was observed, respectively. Time intervals of 15 and 30 s yield no further reduction in motion uncertainty compared to a 1 min time interval.