International Society of Urological Pathology (ISUP) Gleason Grade Groups stratify outcomes in the CHHiP Phase 3 prostate radiotherapy trial

OBJECTIVES

To compare the results of Gleason Grade Group (GGG) classification following central pathology review with previous local pathology assessment, and to examine the difference between using overall and worst GGG in a large patient cohort treated with radiotherapy and short-course hormone therapy.

PATIENTS AND METHODS

Patients with low- to high-risk localized prostate cancer were randomized into the multicentre CHHiP fractionation trial between 2002 and 2011. Patients received short-course hormone therapy (≤6 month) and radical intensity-modulated radiotherapy (IMRT). Of 2749 consented patients, 1875 had adequate diagnostic biopsy tissue for blinded central pathology review. The median follow-up was 9.3 years. Agreement between local pathology and central pathology-derived GGG and between central pathology-derived overall and worst GGG was assessed using kappa (κ) statistics. Multivariate Cox regression and Kaplan-Meier methods were used to compare the biochemical/clinical failure (BCF) and distant metastases (DM) outcomes of patients with GGG 1-5.

RESULTS

There was poor agreement between local pathology- and central pathology-derived GGG (κ = 0.19) but good agreement between overall and worst GGG on central pathology review (κ = 0.89). Central pathology-derived GGG stratified BCF and DM outcomes better than local pathology, while overall and worst GGG on central pathology review performed similarly. GGG 3 segregated with GGG 4 for BCF, with BCF-free rates of 90%, 82%, 74%, 71% and 58% for GGGs 1-5, respectively, at 8 years when assessed using overall GGG. There was a progressive decrease in DM-free rates from 98%, 96%, 92%, 88% and 83% for GGGs 1-5, respectively, at 8 years with overall GGG. Patients (n = 57) who were upgraded from GGG 2-3 using worst GS had BCF-free and DM-free rates of 74% and 92% at 8 years. CHHiP eligibility criteria limit the interpretation of these results.

CONCLUSION

Contemporary review of International Society of Urological Pathology GGG successfully stratified patients treated with short-course hormone therapy and IMRT with regard to both BCF-free and DM-free outcomes. Patients upgraded from GGG 2 to GGG 3 using worst biopsy GS segregate with GGG 3 on long-term follow-up. We recommend that both overall and worst GS be used to derive GGG.

Gastrointestinal Toxicity Prediction Not Influenced by Rectal Contour or Dose-Volume Histogram Definition

PURPOSE

Rectal dose delivered during prostate radiation therapy is associated with gastrointestinal toxicity. Treatment plans are commonly optimized using rectal dose-volume constraints, often whole-rectum relative-volumes (%). We investigated whether improved rectal contouring, use of absolute-volumes (cc), or rectal truncation might improve toxicity prediction.

METHODS AND MATERIALS

Patients from the CHHiP trial (receiving 74 Gy/37 fractions [Fr] vs 60 Gy/20 Fr vs 57 Gy/19 Fr) were included if radiation therapy plans were available (2350/3216 patients), plus toxicity data for relevant analyses (2170/3216 patients). Whole solid rectum relative-volumes (%) dose-volume-histogram (DVH), as submitted by treating center (original contour), was assumed standard-of-care. Three investigational rectal DVHs were generated: (1) reviewed contour per CHHiP protocol; (2) original contour absolute volumes (cc); and (3) truncated original contour (2 versions; ±0 and ±2 cm from planning target volume [PTV]). Dose levels of interest (V30, 40, 50, 60, 70, 74 Gy) in 74 Gy arm were converted by equivalent-dose-in-2 Gy-Fr (EQD2α/β= 3 Gy) for 60 Gy/57 Gy arms. Bootstrapped logistic models predicting late toxicities (frequency G1+/G2+, bleeding G1+/G2+, proctitis G1+/G2+, sphincter control G1+, stricture/ulcer G1+) were compared by area-undercurve (AUC) between standard of care and the 3 investigational rectal definitions.

RESULTS

The alternative dose/volume parameters were compared with the original relative-volume (%) DVH of the whole rectal contour, itself fitted as a weak predictor of toxicity (AUC range, 0.57-0.65 across the 8 toxicity measures). There were no significant differences in toxicity prediction for: (1) original versus reviewed rectal contours (AUCs, 0.57-0.66; P = .21-.98); (2) relative- versus absolute-volumes (AUCs, 0.56-0.63; P = .07-.91); and (3) whole-rectum versus truncation at PTV ± 2 cm (AUCs, 0.57-0.65; P = .05-.99) or PTV ± 0 cm (AUCs, 0.57-0.66; P = .27-.98).

CONCLUSIONS

We used whole-rectum relative-volume DVH, submitted by the treating center, as the standard-of-care dosimetric predictor for rectal toxicity. There were no statistically significant differences in prediction performance when using central rectal contour review, with the use of absolute-volume dosimetry, or with rectal truncation relative to PTV. Whole-rectum relative-volumes were not improved upon for toxicity prediction and should remain standard-of-care.

One versus three weeks hypofractionated whole breast radiotherapy for early breast cancer treatment: the FAST-Forward phase III RCT

Background

FAST-Forward aimed to identify a 5-fraction schedule of adjuvant radiotherapy delivered in 1 week that was non-inferior in terms of local cancer control and as safe as the standard 15-fraction regimen after primary surgery for early breast cancer. Published acute toxicity and 5-year results are presented here with other aspects of the trial.

Design

Multicentre phase III non-inferiority trial. Patients with invasive carcinoma of the breast (pT1-3pN0-1M0) after breast conservation surgery or mastectomy randomised (1 : 1 : 1) to 40 Gy in 15 fractions (3 weeks), 27 Gy or 26 Gy in 5 fractions (1 week) whole breast/chest wall (Main Trial). Primary endpoint was ipsilateral breast tumour relapse; assuming 2% 5-year incidence for 40 Gy, non-inferiority pre-defined as < 1.6% excess for 5-fraction schedules (critical hazard ratio = 1.81). Normal tissue effects were assessed independently by clinicians, patients and photographs.

Sub-studies

Two acute skin toxicity sub-studies were undertaken to confirm safety of the test schedules. Primary endpoint was proportion of patients with grade ≥ 3 acute breast skin toxicity at any time from the start of radiotherapy to 4 weeks after completion. Nodal Sub-Study patients had breast/chest wall plus axillary radiotherapy testing the same three schedules, reduced to the 40 and 26 Gy groups on amendment, with the primary endpoint of 5-year patient-reported arm/hand swelling.

Limitations

A sequential hypofractionated or simultaneous integrated boost has not been studied.

Participants

Ninety-seven UK centres recruited 4096 patients (1361:40 Gy, 1367:27 Gy, 1368:26 Gy) into the Main Trial from November 2011 to June 2014. The Nodal Sub-Study recruited an additional 469 patients from 50 UK centres. One hundred and ninety and 162 Main Trial patients were included in the acute toxicity sub-studies.

Results

Acute toxicity sub-studies evaluable patients: (1) acute grade 3 Radiation Therapy Oncology Group toxicity reported in 40 Gy/15 fractions 6/44 (13.6%); 27 Gy/5 fractions 5/51 (9.8%); 26 Gy/5 fractions 3/52 (5.8%). (2) Grade 3 common toxicity criteria for adverse effects toxicity reported for one patient. At 71-month median follow-up in the Main Trial, 79 ipsilateral breast tumour relapse events (40 Gy: 31, 27 Gy: 27, 26 Gy: 21); hazard ratios (95% confidence interval) versus 40 Gy were 27 Gy: 0.86 (0.51 to 1.44), 26 Gy: 0.67 (0.38 to 1.16). With 2.1% (1.4 to 3.1) 5-year incidence ipsilateral breast tumour relapse after 40 Gy, estimated absolute differences versus 40 Gy (non-inferiority test) were -0.3% (-1.0-0.9) for 27 Gy (p = 0.0022) and -0.7% (-1.3-0.3) for 26 Gy (p = 0.00019). Five-year prevalence of any clinician-assessed moderate/marked breast normal tissue effects was 40 Gy: 98/986 (9.9%), 27 Gy: 155/1005 (15.4%), 26 Gy: 121/1020 (11.9%). Across all clinician assessments from 1 to 5 years, odds ratios versus 40 Gy were 1.55 (1.32 to 1.83; p < 0.0001) for 27 Gy and 1.12 (0.94-1.34; p = 0.20) for 26 Gy. Patient and photographic assessments showed higher normal tissue effects risk for 27 Gy versus 40 Gy but not for 26 Gy. Nodal Sub-Study reported no arm/hand swelling in 80% and 77% in 40 Gy and 26 Gy at baseline, and 73% and 76% at 24 months. The prevalence of moderate/marked arm/hand swelling at 24 months was 10% versus 7% for 40 Gy compared with 26 Gy.

Interpretation

Five-year local tumour incidence and normal tissue effects prevalence show 26 Gy in 5 fractions in 1 week is a safe and effective alternative to 40 Gy in 15 fractions for patients prescribed adjuvant local radiotherapy after primary surgery for early-stage breast cancer.

Future work

Ten-year Main Trial follow-up is essential. Inclusion in hypofractionation meta-analysis ongoing. A future hypofractionated boost trial is strongly supported.

Trial registration

FAST-Forward was sponsored by The Institute of Cancer Research and was registered as ISRCTN19906132.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 09/01/47) and is published in full in Health Technology Assessment; Vol. 27, No. 25. See the NIHR Funding and Awards website for further award information.

Acute Toxicity of Hypofractionated and Conventionally Fractionated (Chemo)Radiotherapy Regimens for Bladder Cancer: An Exploratory Analysis from the RAIDER Trial

AIMS

Adding concurrent (chemo)therapy to radiotherapy improves outcomes for muscle-invasive bladder cancer patients. A recent meta-analysis showed superior invasive locoregional disease control for a hypofractionated 55 Gy in 20 fractions schedule compared with 64 Gy in 32 fractions. In the RAIDER clinical trial, patients undergoing 20 or 32 fractions of radical radiotherapy were randomised (1:1:2) to standard radiotherapy or to standard-dose or escalated-dose adaptive radiotherapy. Neoadjuvant chemotherapy and concomitant therapy were permitted. We report exploratory analyses of acute toxicity by concomitant therapy-fractionation schedule combination.

MATERIALS AND METHODS

Participants had unifocal bladder urothelial carcinoma staged T2-T4a N0 M0. Acute toxicity was assessed (Common Terminology Criteria for Adverse Events) weekly during radiotherapy and at 10 weeks after the start of treatment. Within each fractionation cohort, non-randomised comparisons of the proportion of patients reporting treatment emergent grade 2 or worse genitourinary, gastrointestinal or other adverse events at any point in the acute period were carried out using Fisher's exact tests.

RESULTS

Between September 2015 and April 2020, 345 (163 receiving 20 fractions; 182 receiving 32 fractions) patients were recruited from 46 centres. The median age was 73 years; 49% received neoadjuvant chemotherapy; 71% received concomitant therapy, with 5-fluorouracil/mitomycin C most commonly used: 44/114 (39%) receiving 20 fractions; 94/130 (72%) receiving 32 fractions. The acute grade 2+ gastrointestinal toxicity rate was higher in those receiving concomitant therapy compared with radiotherapy alone in the 20-fraction cohort [54/111 (49%) versus 7/49 (14%), P < 0.001] but not in the 32-fraction cohort (P = 0.355). Grade 2+ gastrointestinal toxicity was highest for gemcitabine, with evidence of significant differences across therapies in the 32-fraction cohort (P = 0.006), with a similar pattern but no significant differences in the 20-fraction cohort (P = 0.099). There was no evidence of differences in grade 2+ genitourinary toxicity between concomitant therapies in either the 20- or 32-fraction cohorts.

CONCLUSION

Grade 2+ acute adverse events are common. The toxicity profile varied by type of concomitant therapy; the gastrointestinal toxicity rate seemed to be higher in patients receiving gemcitabine.

Dose-escalated simultaneous integrated boost radiotherapy in early breast cancer (IMPORT HIGH): a multicentre, phase 3, non-inferiority, open-label, randomised controlled trial

BACKGROUND

A tumour-bed boost delivered after whole-breast radiotherapy increases local cancer-control rates but requires more patient visits and can increase breast hardness. IMPORT HIGH tested simultaneous integrated boost against sequential boost with the aim of reducing treatment duration while maintaining excellent local control and similar or reduced toxicity.

METHODS

IMPORT HIGH is a phase 3, non-inferiority, open-label, randomised controlled trial that recruited women after breast-conserving surgery for pT1-3pN0-3aM0 invasive carcinoma from radiotherapy and referral centres in the UK. Patients were randomly allocated to receive one of three treatments in a 1:1:1 ratio, with computer-generated random permuted blocks used to stratify patients by centre. The control group received 40 Gy in 15 fractions to the whole breast and 16 Gy in 8 fractions sequential photon tumour-bed boost. Test group 1 received 36 Gy in 15 fractions to the whole breast, 40 Gy in 15 fractions to the partial breast, and 48 Gy in 15 fractions concomitant photon boost to the tumour-bed volume. Test group 2 received 36 Gy in 15 fractions to the whole breast, 40 Gy in 15 fractions to the partial breast, and 53 Gy in 15 fractions concomitant photon boost to the tumour-bed volume. The boost clinical target volume was the clip-defined tumour bed. Patients and clinicians were not masked to treatment allocation. The primary endpoint was ipsilateral breast tumour relapse (IBTR) analysed by intention to treat; assuming 5% 5-year incidence with the control group, non-inferiority was predefined as 3% or less absolute excess in the test groups (upper limit of two-sided 95% CI). Adverse events were assessed by clinicians, patients, and photographs. This trial is registered with the ISRCTN registry, ISRCTN47437448, and is closed to new participants.

FINDINGS

Between March 4, 2009, and Sept 16, 2015, 2617 patients were recruited. 871 individuals were assigned to the control group, 874 to test group 1, and 872 to test group 2. Median boost clinical target volume was 13 cm3 (IQR 7 to 22). At a median follow-up of 74 months there were 76 IBTR events (20 for the control group, 21 for test group 1, and 35 for test group 2). 5-year IBTR incidence was 1·9% (95% CI 1·2 to 3·1) for the control group, 2·0% (1·2 to 3·2) for test group 1, and 3·2% (2·2 to 4·7) for test group 2. The estimated absolute differences versus the control group were 0·1% (-0·8 to 1·7) for test group 1 and 1·4% (0·03 to 3·8) for test group 2. The upper confidence limit for test group 1 versus the control group indicated non-inferiority for 48 Gy. Cumulative 5-year incidence of clinician-reported moderate or marked breast induration was 11·5% for the control group, 10·6% for test group 1 (p=0·40 vs control group), and 15·5% for test group 2 (p=0·015 vs control group).

INTERPRETATION

In all groups 5-year IBTR incidence was lower than the 5% originally expected regardless of boost sequencing. Dose-escalation is not advantageous. 5-year moderate or marked adverse event rates were low using small boost volumes. Simultaneous integrated boost in IMPORT HIGH was safe and reduced patient visits.

FUNDING

Cancer Research UK.

Randomised phase II trial of adaptive image guided radiotherapy in muscle invasive bladder cancer: Late toxicity and cancer outcomes

446

Background: The bladder is a mobile, deformable structure which makes radiotherapy (RT) delivery challenging. Plan of the day (POD) adaptive image guided RT and tumour boost dose escalation can optimise treatment. We aimed to define a feasible, safe schedule for muscle invasive bladder cancer (BC) using these techniques. Methods: RAIDER (ISRCTN 26779187) is a 3-arm, international phase II trial. Participants (pts) had unifocal T2-T4a urothelial BC and were randomized (1:1:2) to: standard whole bladder RT (WBRT), standard dose adaptive tumour focused RT (SART) or dose escalated adaptive tumour boost RT (DART). Two fractionation (f) schedules recruited independently. WBRT and SART dose was 64Gy/32f or 55Gy/20f and DART was 70Gy/32f or 60Gy/20f. For SART and DART, POD (small, medium, large) was chosen daily. Neoadjuvant chemotherapy (NAC) and concomitant radiosensitising therapy (CTh) were permitted. Primary endpoint is proportion of pts with RT related CTCAE grade≥3 (G≥3) toxicity 6-18 months (m) after RT. A non-comparative design to rule out >20% G≥3 toxicity in DART pts required 57 evaluable DART pts in each fractionation cohort (90% power, 5% 1-sided alpha). Adverse events (AE) are treatment emergent with RT relatedness assessed blind to treatment allocation. In each fractionation cohort, toxicity analysis is by treatment received in the evaluable population (pts with at ≥1 toxicity assessment between 6-18m). 3m local control was assessed by cystoscopic biopsy. Cancer outcomes are analysed by intention-to-treat with fractionation cohorts combined. Results: 345 pts were randomised (Oct 2015 - Apr 2020): 46/41 WBRT, 46/41 SART and 90/81 DART pts in 32f/20f cohorts respectively. Baseline characteristics for 32f/20f were median age 73 years (IQR 67, 79)/ 72 (67, 79); 83%/ 78% T2; 46%/ 52% had NAC and 71%/ 70% CTh. Median follow-up was 32f: 38.2m (IQR 26.2, 50.2), 20f: 42.1m (35.6, 50.1). 3588/6222 (58%) fractions delivered to SART and DART pts used small or large POD. Late toxicity outcomes are shown in table. RT related G≥3 in 20f DART was 1/58 (90% CI 0.1, 7.9) and in 32f DART was 0/57. 3m local control was achieved in 44/51 (86%) WBRT, 45/53 (85%) SART and 82/92(89%) DART. 2 year survival was 79% (95% CI: 69, 86) WBRT, 74% (63, 82) SART and 80% (73, 85) DART. Conclusions: Late G≥3 toxicity was low in all treatment groups. 20f and 32f DART was safe and feasible to deliver with toxicity rates below predefined thresholds. Local control for image guided (chemo)RT was good. CTCAE G≥3 and G≥2 treatment emergent toxicity 6-18m after RT. Clinical trial information: 26779187 . [Table: see text]

10-Year efficacy and co-morbidity outcomes of a phase III randomised trial of conventional vs. hypofractionated high dose intensity modulated radiotherapy for prostate cancer (CHHiP; CRUK/06/016)

304

Background: Five-year results from the CHHiP trial indicated that moderate hypofractionation of 60 Gray (Gy)/20 fractions (f) was non-inferior to 74Gy/37f (Lancet Oncology, 2016). Reporting of long-term efficacy and side effects is essential in a patient population that remain at risk of recurrence years after treatment. Here we report specific co-morbidity data collected at 10 years and an update of efficacy. Methods: Between October 2002 and June 2011, 3216 men with node negative T1b-T3a localised prostate cancer with risk of seminal vesical involvement ≤30% were randomised (1:1:1 ratio) to 74Gy/37f (control), 60Gy/20f or 57Gy/19f. Patients received 3-6 months of androgen deprivation prior to radiotherapy. The primary endpoint was time to biochemical failure (Phoenix consensus guidelines) or clinical failure (BCF). The non-inferiority design specified a critical hazard ratio (HR) of 1.208 for each hypofractionated schedule compared to control. Data on specific radiotherapy related co-morbidities were collected at 10-year follow-up and are presented as frequency and percentages. Analysis was by intention-to-treat; HRs quoted are unadjusted. Results: With a median follow up of 12.1 years, 10-year BCF-free rates (95% CI) were 74Gy: 76.0% (73.1%, 78.6%); 60Gy: 79.8% (77.1%, 82.3%) and 57Gy: 73.4% (70.5%, 76.1%). For 60Gy/20f, non-inferiority was confirmed: HR60=0.84 (90% CI 0.72, 0.97) with borderline significance for superiority (HR=0.84 (95% CI 0.70, 1.00). As in the primary analysis, for 57Gy/19f, non-inferiority could not be declared: HR57=1.13 (90% CI 0.98, 1.30). 10-year overall survival (95% CI) was 78.5% (75.9%, 81.0%), 82.9% (80.4%, 85.0%) and 79.9% (77.3%, 82.2%) in the 74Gy, 60Gy and 57Gy groups. Bone fractures were reported in 2% (15/700), 2% (19/771) and 3% (22/719) of patients in the 74Gy, 60Gy and 57Gy groups respectively at 10 years. The most common intervention reported was a sigmoidoscopy with 12% (79/681), 8% (60/739) and 9% (65/702) in the 74Gy, 60Gy and 57Gy groups respectively. Of those patients who underwent a sigmoidoscopy it was due to symptoms for 81% (63/78) 81% (48/59) and 85% (55/65) of patients in the 74Gy, 60Gy and 57Gy group respectively. Frequencies of all other pre-specified co-morbidities or related interventions (ureteric obstruction, bowel strictures, trans-urethral resection of prostate, urethrotomy, urethral dilatation or long term catheterisation or treatment of proctopathy with steroid, sucralfate, formalin, laser coagulation or rectal diversion) were <1% in all groups. Conclusions: With a median follow-up of 12 years, oncological outcomes following 60Gy/20f continue to be non-inferior to those with 74Gy/37f. Late co-morbidities were very low across all treatment groups. These data support the long-term safety of moderate hypofractionation. Clinical trial information: 97182923 .

Sequencing of Androgen-Deprivation Therapy of Short Duration With Radiotherapy for Nonmetastatic Prostate Cancer (SANDSTORM): A Pooled Analysis of 12 Randomized Trials

PURPOSE

The sequencing of androgen-deprivation therapy (ADT) with radiotherapy (RT) may affect outcomes for prostate cancer in an RT-field size-dependent manner. Herein, we investigate the impact of ADT sequencing for men receiving ADT with prostate-only RT (PORT) or whole-pelvis RT (WPRT).

MATERIALS AND METHODS

Individual patient data from 12 randomized trials that included patients receiving neoadjuvant/concurrent or concurrent/adjuvant short-term ADT (4-6 months) with RT for localized disease were obtained from the Meta-Analysis of Randomized trials in Cancer of the Prostate consortium. Inverse probability of treatment weighting (IPTW) was performed with propensity scores derived from age, initial prostate-specific antigen, Gleason score, T stage, RT dose, and mid-trial enrollment year. Metastasis-free survival (primary end point) and overall survival (OS) were assessed by IPTW-adjusted Cox regression models, analyzed independently for men receiving PORT versus WPRT. IPTW-adjusted Fine and Gray competing risk models were built to evaluate distant metastasis (DM) and prostate cancer-specific mortality.

RESULTS

Overall, 7,409 patients were included (6,325 neoadjuvant/concurrent and 1,084 concurrent/adjuvant) with a median follow-up of 10.2 years (interquartile range, 7.2-14.9 years). A significant interaction between ADT sequencing and RT field size was observed for all end points (P interaction < .02 for all) except OS. With PORT (n = 4,355), compared with neoadjuvant/concurrent ADT, concurrent/adjuvant ADT was associated with improved metastasis-free survival (10-year benefit 8.0%, hazard ratio [HR], 0.65; 95% CI, 0.54 to 0.79; P < .0001), DM (subdistribution HR, 0.52; 95% CI, 0.33 to 0.82; P = .0046), prostate cancer-specific mortality (subdistribution HR, 0.30; 95% CI, 0.16 to 0.54; P < .0001), and OS (HR, 0.69; 95% CI, 0.57 to 0.83; P = .0001). However, in patients receiving WPRT (n = 3,049), no significant difference in any end point was observed in regard to ADT sequencing except for worse DM (HR, 1.57; 95% CI, 1.20 to 2.05; P = .0009) with concurrent/adjuvant ADT.

CONCLUSION

ADT sequencing exhibits a significant impact on clinical outcomes with a significant interaction with field size. Concurrent/adjuvant ADT should be the standard of care where short-term ADT is indicated in combination with PORT.

The Fraction Size Sensitivity of Late Genitourinary Toxicity: Analysis of Alpha/Beta (α/β) Ratios in the CHHiP Trial

PURPOSE

Moderately hypofractionated external beam intensity modulated radiation therapy (RT) for prostate cancer is now standard-of-care. Normal tissue toxicity responses to fraction size alteration are nonlinear: the linear-quadratic model is a widely used framework accounting for this, through the α/β ratio. Few α/β ratio estimates exist for human late genitourinary endpoints; here we provide estimates derived from a hypofractionation trial.

METHODS AND MATERIALS

The CHHiP trial randomized 3216 men with localized prostate cancer 1:1:1 between conventionally fractionated intensity modulated RT (74 Gy/37 fractions (Fr)) and 2 moderately hypofractionated regimens (60 Gy/20 Fr and 57 Gy/19 Fr). RT plan and suitable follow-up assessment was available for 2206 men. Three prospectively assessed clinician-reported toxicity scales were amalgamated for common genitourinary endpoints: dysuria, hematuria, incontinence, reduced flow/stricture, and urine frequency. Per endpoint, only patients with baseline zero toxicity were included. Three models for endpoint grade ≥1 (G1+) and G2+ toxicity were fitted: Lyman Kutcher-Burman (LKB) without equivalent dose in 2 Gy/Fr (EQD2) correction [LKB-NoEQD2]; LKB with EQD2-correction [LKB-EQD2]; LKB-EQD2 with dose-modifying-factor (DMF) inclusion [LKB-EQD2-DMF]. DMFs were age, diabetes, hypertension, pelvic surgery, prior transurethral resection of prostate (TURP), overall treatment time and acute genitourinary toxicity (G2+). Bootstrapping generated 95% confidence intervals and unbiased performance estimates. Models were compared by likelihood ratio test.

RESULTS

The LKB-EQD2 model significantly improved performance over LKB-NoEQD2 for just 3 endpoints: dysuria G1+ (α/β = 2.0 Gy; 95% confidence interval [CI], 1.2-3.2 Gy), hematuria G1+ (α/β = 0.9 Gy; 95% CI, 0.1-2.2 Gy) and hematuria G2+ (α/β = 0.6 Gy; 95% CI, 0.1-1.7 Gy). For these 3 endpoints, further incorporation of 2 DMFs improved on LKB-EQD2: acute genitourinary toxicity and prior TURP (hematuria G1+ only), but α/β ratio estimates remained stable.

CONCLUSIONS

Inclusion of EQD2-correction significantly improved model fitting for dysuria and hematuria endpoints, where fitted α/β ratio estimates were low: 0.6 to 2 Gy. This suggests therapeutic gain for clinician-reported GU toxicity, through hypofractionation, might be lower than expected by typical late α/β ratio assumptions of 3 to 5 Gy.

Local Failure Events in Prostate Cancer Treated with Radiotherapy: A Pooled Analysis of 18 Randomized Trials from the Meta-analysis of Randomized Trials in Cancer of the Prostate Consortium (LEVIATHAN)

CONTEXT

The prognostic importance of local failure after definitive radiotherapy (RT) in National Comprehensive Cancer Network intermediate- and high-risk prostate cancer (PCa) patients remains unclear.

OBJECTIVE

To evaluate the prognostic impact of local failure and the kinetics of distant metastasis following RT.

EVIDENCE ACQUISITION

A pooled analysis was performed on individual patient data of 12 533 PCa (6288 high-risk and 6245 intermediate-risk) patients enrolled in 18 randomized trials (conducted between 1985 and 2015) within the Meta-analysis of Randomized Trials in Cancer of the Prostate Consortium. Multivariable Cox proportional hazard (PH) models were developed to evaluate the relationship between overall survival (OS), PCa-specific survival (PCSS), distant metastasis-free survival (DMFS), and local failure as a time-dependent covariate. Markov PH models were developed to evaluate the impact of specific transition states.

EVIDENCE SYNTHESIS

The median follow-up was 11 yr. There were 795 (13%) local failure events and 1288 (21%) distant metastases for high-risk patients and 449 (7.2%) and 451 (7.2%) for intermediate-risk patients, respectively. For both groups, 81% of distant metastases developed from a clinically relapse-free state (cRF state). Local failure was significantly associated with OS (hazard ratio [HR] 1.17, 95% confidence interval [CI] 1.06-1.30), PCSS (HR 2.02, 95% CI 1.75-2.33), and DMFS (HR 1.94, 95% CI 1.75-2.15, p < 0.01 for all) in high-risk patients. Local failure was also significantly associated with DMFS (HR 1.57, 95% CI 1.36-1.81) but not with OS in intermediate-risk patients. Patients without local failure had a significantly lower HR of transitioning to a PCa-specific death state than those who had local failure (HR 0.32, 95% CI 0.21-0.50, p < 0.001). At later time points, more distant metastases emerged after a local failure event for both groups.

CONCLUSIONS

Local failure is an independent prognosticator of OS, PCSS, and DMFS in high-risk and of DMFS in intermediate-risk PCa. Distant metastasis predominantly developed from the cRF state, underscoring the importance of addressing occult microscopic disease. However a "second wave" of distant metastases occurs subsequent to local failure events, and optimization of local control may reduce the risk of distant metastasis.

PATIENT SUMMARY

Among men receiving definitive radiation therapy for high- and intermediate-risk prostate cancer, about 10% experience local recurrence, and they are at significantly increased risks of further disease progression. About 80% of patients who develop distant metastasis do not have a detectable local recurrence preceding it.

PEARLS - A multicentre phase II/III trial of extended field radiotherapy for androgen sensitive prostate cancer patients with PSMA-avid pelvic and/or para-aortic lymph nodes at presentation

PEARLS is a multi-stage randomised controlled trial for prostate cancer patients with pelvic and/or para-aortic PSMA-avid lymph node disease at presentation. The aim of the trial is to determine whether extending the radiotherapy field to cover the para-aortic lymph nodes (up to L1/L2 vertebral interspace) can improve outcomes for this patient group.

Chemoradiotherapy in Muscle-invasive Bladder Cancer: 10-yr Follow-up of the Phase 3 Randomised Controlled BC2001 Trial

BACKGROUND

BC2001, the largest randomised trial of bladder-sparing treatment for muscle-invasive bladder cancer (MIBC), demonstrated improvement in locoregional control by adding fluorouracil and mitomycin C to radiotherapy (James ND, Hussain SA, Hall E, et al. Radiotherapy with or without chemotherapy in muscle-invasive bladder cancer. N Engl J Med 2012;366:1477-88). There are limited data on long-term recurrence risk.

OBJECTIVE

To determine whether benefit of adding chemotherapy to radiotherapy for MIBC is maintained in the long term.

DESIGN, SETTING, AND PARTICIPANTS

A phase 3 randomised controlled 2 × 2 factorial trial was conducted. Between 2001 and 2008, 458 patients with T2-T4a N0M0 MIBC were enrolled; 360 were randomised to radiotherapy (178) or chemoradiotherapy (182), and 218 were randomised to standard whole-bladder radiotherapy (108) or reduced high-dose-volume radiotherapy (111). The median follow-up time was 9.9 yr. The trial is registered (ISRCTN68324339).

INTERVENTION

Radiotherapy: 55 Gy in 20 fractions over 4 wk or 64 Gy in 32 fractions over 6.5 wk; concurrent chemotherapy: 5-fluorouracil and mitomycin C.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Locoregional control (primary endpoint), invasive locoregional control, toxicity, rate of salvage cystectomy, disease-free survival (DFS), metastasis-free survival (MFS), bladder cancer-specific survival (BCSS), and overall survival. Cox regression was used. The analysis of efficacy outcomes was by intention to treat.

RESULTS AND LIMITATIONS

Chemoradiotherapy improved locoregional control (hazard ratio [HR] 0.61 [95% confidence interval {CI} 0.43-0.86], p = 0.004) and invasive locoregional control (HR 0.55 [95% CI 0.36-0.84], p = 0.006). This benefit translated, albeit nonsignificantly, for disease-related outcomes: DFS (HR 0.78 [95% CI 0.60-1.02], p = 0.069), MFS (HR 0.78, [95% CI 0.58-1.05], p = 0.089), overall survival (HR = 0.88 [95% CI 0.69-1.13], p = 0.3), and BCSS (HR 0.79 [95% CI 0.59-1.06], p = 0.11). The 5-yr cystectomy rate was 14% (95% CI 9-21%) with chemoradiotherapy versus 22% (95% CI 16-31%) with radiotherapy alone (HR 0.54, [95% CI 0.31-0.95], p = 0.034). No differences were seen between standard and reduced high-dose-volume radiotherapy.

CONCLUSIONS

Long-term findings confirm the benefit of adding concomitant 5-fluorouracil and mitomycin C to radiotherapy for MIBC.

PATIENT SUMMARY

We looked at long-term outcomes of a phase 3 clinical trial testing radiotherapy with or without chemotherapy for patients with invasive bladder cancer. We concluded that the benefit of adding chemotherapy to radiotherapy was maintained over 10 yr.

Abiraterone acetate plus prednisolone for metastatic patients starting hormone therapy: 5-year follow-up results from the STAMPEDE randomised trial (NCT00268476)

Abiraterone acetate plus prednisolone (AAP) previously demonstrated improved survival in STAMPEDE, a multiarm, multistage platform trial in men starting long-term hormone therapy for prostate cancer. This long-term analysis in metastatic patients was planned for 3 years after the first results. Standard-of-care (SOC) was androgen deprivation therapy. The comparison randomised patients 1:1 to SOC-alone with or without daily abiraterone acetate 1000 mg + prednisolone 5 mg (SOC + AAP), continued until disease progression. The primary outcome measure was overall survival. Metastatic disease risk group was classified retrospectively using baseline CT and bone scans by central radiological review and pathology reports. Analyses used Cox proportional hazards and flexible parametric models, accounting for baseline stratification factors. One thousand and three patients were contemporaneously randomised (November 2011 to January 2014): median age 67 years; 94% newly-diagnosed; metastatic disease risk group: 48% high, 44% low, 8% unassessable; median PSA 97 ng/mL. At 6.1 years median follow-up, 329 SOC-alone deaths (118 low-risk, 178 high-risk) and 244 SOC + AAP deaths (75 low-risk, 145 high-risk) were reported. Adjusted HR = 0.60 (95% CI: 0.50-0.71; P = 0.31 × 10^-9 ) favoured SOC + AAP, with 5-years survival improved from 41% SOC-alone to 60% SOC + AAP. This was similar in low-risk (HR = 0.55; 95% CI: 0.41-0.76) and high-risk (HR = 0.54; 95% CI: 0.43-0.69) patients. Median and current maximum time on SOC + AAP was 2.4 and 8.1 years. Toxicity at 4 years postrandomisation was similar, with 16% patients in each group reporting grade 3 or higher toxicity. A sustained and substantial improvement in overall survival of all metastatic prostate cancer patients was achieved with SOC + abiraterone acetate + prednisolone, irrespective of metastatic disease risk group.

High-dose Radiotherapy or Androgen Deprivation Therapy (HEAT) as Treatment Intensification for Localized Prostate Cancer: An Individual Patient-data Network Meta-analysis from the MARCAP Consortium

BACKGROUND

The relative benefits of radiotherapy (RT) dose escalation and the addition of short-term or long-term androgen deprivation therapy (STADT or LTADT) in the treatment of prostate cancer are unknown.

OBJECTIVE

To perform a network meta-analysis (NMA) of relevant randomized trials to compare the relative benefits of RT dose escalation ± STADT or LTADT.

DESIGN, SETTING, AND PARTICIPANTS

An NMA of individual patient data from 13 multicenter randomized trials was carried out for a total of 11862 patients. Patients received one of the six permutations of low-dose RT (64 to <74 Gy) ± STADT or LTADT, high-dose RT (≥74 Gy), or high-dose RT ± STADT or LTADT.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

Metastasis-free survival (MFS) was the primary endpoint. Frequentist and Bayesian NMAs were performed to rank the various treatment strategies by MFS and biochemical recurrence-free survival (BCRFS).

RESULTS AND LIMITATIONS

Median follow-up was 8.8 yr (interquartile range 5.7-11.5). The greatest relative improvement in outcomes was seen for addition of LTADT, irrespective of RT dose, followed by addition of STADT, irrespective of RT dose. RT dose escalation did not improve MFS either in the absence of ADT (hazard ratio [HR] 0.97, 95% confidence interval [CI] 0.80-1.18) or with STADT (HR 0.99, 95% CI 0.8-1.23) or LTADT (HR 0.94, 95% CI 0.65-1.37). According to P-score ranking and rankogram analysis, high-dose RT + LTADT was the optimal treatment strategy for both BCRFS and longer-term outcomes.

CONCLUSIONS

Conventionally escalated RT up to 79.2 Gy, alone or in the presence of ADT, does not improve MFS, while addition of STADT or LTADT to RT alone, regardless of RT dose, consistently improves MFS. RT dose escalation does provide a high probability of improving BCRFS and, provided it can be delivered without compromising quality of life, may represent the optimal treatment strategy when used in conjunction with ADT.

PATIENT SUMMARY

Using a higher radiotherapy dose when treating prostate cancer does not reduce the chance of developing metastases or death, but it does reduce the chance of having a rise in prostate-specific antigen (PSA) signifying recurrence of cancer. Androgen deprivation therapy improves all outcomes. A safe increase in radiotherapy dose in conjunction with androgen deprivation therapy may be the optimal treatment.

Nonrandomized Comparison of Efficacy and Side Effects of Bicalutamide Compared With Luteinizing Hormone-Releasing Hormone (LHRH) Analogs in Combination With Radiation Therapy in the CHHiP Trial

PURPOSE

CHHiP is a randomized trial evaluating moderately hypofractionated radiation therapy for treatment of localized prostate cancer. Of all participants, 97% of them had concurrent short-course hormone therapy (HT), either luteinizing hormone-releasing hormone analog (LHRHa) or 150 mg of bicalutamide daily. This exploratory analysis compares efficacy and side effects in a nonrandomized comparison.

METHODS AND MATERIALS

In our study, 2700 patients received LHRHa and 403 received bicalutamide. The primary endpoint was biochemical/clinical failure. Groups were compared with Cox regression adjusted for various prognostic factors and stratified by radiation therapy dose. A key secondary endpoint was erectile dysfunction (ED) assessed by clinicians (using scores from Late Effects on Normal Tissues: Subjective/Objective/Management [LENT-SOM] subjective erectile function for vaginal penetration) and patients (single items within the University of California-Los Angeles Prostate Cancer Index [UCLA PCI] and Expanded Prostate Cancer Index Composite [EPIC]-50 questionnaires) at 2 years and compared between HT regimens by χ2 trend test.

RESULTS

Bicalutamide patients were significantly younger (median 67 vs 69 years LHRHa). Median follow-up was 9.3 years. There was no difference in biochemical or clinical failure with an adjusted hazard ratio or 0.97 (95% confidence interval, 0.77-1.23; P = .8). At 2 years, grade ≥2 LENT-SOM ED was reported in significantly more LHRHa patients (313 out of 590; 53%) versus bicalutamide (17 out of 68; 25%) (P < .0001). There were no differences in ED seen with UCLA-PCI and EPIC-50 questionnaires.

CONCLUSIONS

In this nonrandomized comparison, there was no evidence of a difference in efficacy according to type of HT received. Bicalutamide preserved clinician assessed (LENT-SOM) erectile function at 2 years but patient-reported outcomes were similar between groups.

Mogamulizumab for Previously Treated Mycosis Fungoides and Sézary Syndrome: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Kyowa Kirin) of mogamulizumab (Poteligeo®), as part of the single technology appraisal process, to submit evidence for its clinical and cost-effectiveness for previously treated mycosis fungoides (MF) and Sézary syndrome (SS). Kleijnen Systematic Reviews Ltd, in collaboration with Maastricht University Medical Centre, was commissioned to act as the independent evidence review group (ERG). This paper summarises the company submission (CS), presents the ERG's critical review of the clinical and cost-effectiveness evidence in the CS, highlights the key methodological considerations and describes the development of the NICE guidance by the Appraisal Committee. Based on a systematic literature review, one randomised controlled trial, MAVORIC, was identified showing favourable results in patients with MF and SS. However, MAVORIC compared mogamulizumab to vorinostat, which is not standard care in the NHS, and there is uncertainty due to the study design, specifically crossover of patients. Based on a "naïve comparison of results from the vorinostat arm of the MAVORIC study and the physician's choice arm (methotrexate or bexarotene i.e. United Kingdom [UK] standard treatments) of the ALCANZA study as well as comparison to Phase II bexarotene data", the company considered vorinostat to be "a reasonable proxy for current standard of care in the NHS". The ERG considered, based on the limited data available, that the comparability of vorinostat (MAVORIC) and physician's choice (ALCANZA) could not be established. In response to the Appraisal Consultation Document, the company provided an unanchored matched adjusted indirect comparison (MAIC) of mogamulizumab with UK standard care by analysing Hospital Episode Statistics (HES) data. However, given the high risk of bias of an unanchored MAIC, these results needed to be regarded with a considerable degree of caution. The economic analysis suffered from uncertainty because there was no trial evidence on the comparator in the England and Wales National Health Service (NHS), and it was unclear to what extent the trial (MAVORIC) comparator (vorinostat) was comparable to standard care, referred to as established clinical management (ECM) in the NHS. The evidence for overall survival had not reached maturity and was confounded by treatment switching, for which different crossover adjustment methods produced large variations in life years. Caregiver utilities were applied in the analysis, but there was a lack of guidance on their application and whether these were indicated in this appraisal. After consultation, the company updated the economic analysis with the MAIC. Incremental cost-effectiveness ratios comparing mogamulizumab against ECM were (depending on whether the HES or MAVORIC comparison were used) £31,030 or £32,634 per quality-adjusted life years (QALYs) gained according to the company's base case and £38,274 or £80,555 per QALY gained according to the ERG's base case. NICE did not recommend mogamulizumab for treating MF or SS in adults who have had at least one previous systemic treatment. This decision was subsequently appealed, and an appeal decision has been reached.

PEARLS: A multicenter phase II/III trial of extended field radiotherapy for androgen-sensitive prostate cancer patients with PSMA‐avid pelvic and para-aortic lymph nodes at presentation

TPS199

Background: Optimal management for lymph node (LN) positive prostate cancer has not yet been determined. With the emerging role of PSMA-PET/CT in diagnostic staging, identification of this disease status is increasing. The superior border for prostate nodal radiotherapy is variable across different centres. PEARLS (CRUK/19/016) aims to show that extending the radiotherapy field to cover the para-aortic LN (up to L1/L2 vertebral interspace) can improve outcomes for prostate cancer patients with PSMA-avid pelvic LN at presentation. The trial is registered: ISRCTN36344989. Methods: PEARLS is a multi‐stage randomised controlled trial. Men with histologically confirmed prostate cancer with PSMA‐avid nodal disease within the pelvis +/‐ para‐aortic region receiving androgen deprivation therapy +/‐ androgen receptor targeted therapy or docetaxel chemotherapy are eligible. Two cohorts defined by extent of LN disease determined by PSMA‐PET/CT will be recruited: cohort A (pelvic LN at or below the L4/L5 vertebral interspace) and cohort B (para-aortic LN below L1/L2 vertebral interspace). Patients are randomly allocated (1:1) to standard field (dependent on cohort) intensity modulated radiotherapy (IMRT) (control) or extended-field IMRT (experimental) in 20 fractions over 4 weeks. In the control group, cohort A will receive 60Gy to the prostate and 44Gy to the pelvis with an integrated boost of 51Gy to PSMA-avid LN and cohort B will receive 60Gy to the prostate only. In the experimental group, participants in both cohorts will receive 60Gy to the prostate and 44Gy to the pelvis and para‐aortic region with an integrated boost of 51Gy to involved LN. In phase II, the primary endpoint is lower gastrointestinal RTOG grade 2+ toxicity at week 18 from start of radiotherapy. Assuming acceptable toxicity in the first 75 participants receiving extended-field IMRT, the study will move to phase III where the primary endpoint is metastasis‐free survival. The trial aims to recruit 714 patients with pelvic LN to detect a hazard ratio of 0.62 in favour of extended-field IMRT and a further 179 patients with para‐aortic LN disease. The trial was launched in the UK on 25 June 2021. Phase II will be conducted in 20 NHS Trusts across the UK. Clinical trial information: ISRCTN36344989.

Abiraterone acetate and prednisolone with or without enzalutamide for high-risk non-metastatic prostate cancer: a meta-analysis of primary results from two randomised controlled phase 3 trials of the STAMPEDE platform protocol

BACKGROUND

Men with high-risk non-metastatic prostate cancer are treated with androgen-deprivation therapy (ADT) for 3 years, often combined with radiotherapy. We analysed new data from two randomised controlled phase 3 trials done in a multiarm, multistage platform protocol to assess the efficacy of adding abiraterone and prednisolone alone or with enzalutamide to ADT in this patient population.

METHODS

These open-label, phase 3 trials were done at 113 sites in the UK and Switzerland. Eligible patients (no age restrictions) had high-risk (defined as node positive or, if node negative, having at least two of the following: tumour stage T3 or T4, Gleason sum score of 8-10, and prostate-specific antigen [PSA] concentration ≥40 ng/mL) or relapsing with high-risk features (≤12 months of total ADT with an interval of ≥12 months without treatment and PSA concentration ≥4 ng/mL with a doubling time of <6 months, or a PSA concentration ≥20 ng/mL, or nodal relapse) non-metastatic prostate cancer, and a WHO performance status of 0-2. Local radiotherapy (as per local guidelines, 74 Gy in 37 fractions to the prostate and seminal vesicles or the equivalent using hypofractionated schedules) was mandated for node negative and encouraged for node positive disease. In both trials, patients were randomly assigned (1:1), by use of a computerised algorithm, to ADT alone (control group), which could include surgery and luteinising-hormone-releasing hormone agonists and antagonists, or with oral abiraterone acetate (1000 mg daily) and oral prednisolone (5 mg daily; combination-therapy group). In the second trial with no overlapping controls, the combination-therapy group also received enzalutamide (160 mg daily orally). ADT was given for 3 years and combination therapy for 2 years, except if local radiotherapy was omitted when treatment could be delivered until progression. In this primary analysis, we used meta-analysis methods to pool events from both trials. The primary endpoint of this meta-analysis was metastasis-free survival. Secondary endpoints were overall survival, prostate cancer-specific survival, biochemical failure-free survival, progression-free survival, and toxicity and adverse events. For 90% power and a one-sided type 1 error rate set to 1·25% to detect a target hazard ratio for improvement in metastasis-free survival of 0·75, approximately 315 metastasis-free survival events in the control groups was required. Efficacy was assessed in the intention-to-treat population and safety according to the treatment started within randomised allocation. STAMPEDE is registered with ClinicalTrials.gov, NCT00268476, and with the ISRCTN registry, ISRCTN78818544.

FINDINGS

Between Nov 15, 2011, and March 31, 2016, 1974 patients were randomly assigned to treatment. The first trial allocated 455 to the control group and 459 to combination therapy, and the second trial, which included enzalutamide, allocated 533 to the control group and 527 to combination therapy. Median age across all groups was 68 years (IQR 63-73) and median PSA 34 ng/ml (14·7-47); 774 (39%) of 1974 patients were node positive, and 1684 (85%) were planned to receive radiotherapy. With median follow-up of 72 months (60-84), there were 180 metastasis-free survival events in the combination-therapy groups and 306 in the control groups. Metastasis-free survival was significantly longer in the combination-therapy groups (median not reached, IQR not evaluable [NE]-NE) than in the control groups (not reached, 97-NE; hazard ratio [HR] 0·53, 95% CI 0·44-0·64, p<0·0001). 6-year metastasis-free survival was 82% (95% CI 79-85) in the combination-therapy group and 69% (66-72) in the control group. There was no evidence of a difference in metatasis-free survival when enzalutamide and abiraterone acetate were administered concurrently compared with abiraterone acetate alone (interaction HR 1·02, 0·70-1·50, p=0·91) and no evidence of between-trial heterogeneity (I2 p=0·90). Overall survival (median not reached [IQR NE-NE] in the combination-therapy groups vs not reached [103-NE] in the control groups; HR 0·60, 95% CI 0·48-0·73, p<0·0001), prostate cancer-specific survival (not reached [NE-NE] vs not reached [NE-NE]; 0·49, 0·37-0·65, p<0·0001), biochemical failure-free-survival (not reached [NE-NE] vs 86 months [83-NE]; 0·39, 0·33-0·47, p<0·0001), and progression-free-survival (not reached [NE-NE] vs not reached [103-NE]; 0·44, 0·36-0·54, p<0·0001) were also significantly longer in the combination-therapy groups than in the control groups. Adverse events grade 3 or higher during the first 24 months were, respectively, reported in 169 (37%) of 451 patients and 130 (29%) of 455 patients in the combination-therapy and control groups of the abiraterone trial, respectively, and 298 (58%) of 513 patients and 172 (32%) of 533 patients of the combination-therapy and control groups of the abiraterone and enzalutamide trial, respectively. The two most common events more frequent in the combination-therapy groups were hypertension (abiraterone trial: 23 (5%) in the combination-therapy group and six (1%) in control group; abiraterone and enzalutamide trial: 73 (14%) and eight (2%), respectively) and alanine transaminitis (abiraterone trial: 25 (6%) in the combination-therapy group and one (<1%) in control group; abiraterone and enzalutamide trial: 69 (13%) and four (1%), respectively). Seven grade 5 adverse events were reported: none in the control groups, three in the abiraterone acetate and prednisolone group (one event each of rectal adenocarcinoma, pulmonary haemorrhage, and a respiratory disorder), and four in the abiraterone acetate and prednisolone with enzalutamide group (two events each of septic shock and sudden death).

INTERPRETATION

Among men with high-risk non-metastatic prostate cancer, combination therapy is associated with significantly higher rates of metastasis-free survival compared with ADT alone. Abiraterone acetate with prednisolone should be considered a new standard treatment for this population.

FUNDING

Cancer Research UK, UK Medical Research Council, Swiss Group for Clinical Cancer Research, Janssen, and Astellas.

Efficacy and safety of erdafitinib in patients with locally advanced or metastatic urothelial carcinoma: long-term follow-up of a phase 2 study

BACKGROUND

Erdafitinib, a pan-fibroblast growth factor receptor (FGFR) tyrosine kinase inhibitor, was shown to be clinically active and tolerable in patients with advanced urothelial carcinoma and prespecified FGFR alterations in the primary analysis of the BLC2001 study at median 11 months of follow-up. We aimed to assess the long-term efficacy and safety of the selected regimen of erdafitinib determined in the initial part of the study.

METHODS

The open-label, non-comparator, phase 2, BLC2001 study was done at 126 medical centres in 14 countries across Asia, Europe, and North America. Eligible patients were aged 18 years or older with locally advanced and unresectable or metastatic urothelial carcinoma, at least one prespecified FGFR alteration, an Eastern Cooperative Oncology Group performance status of 0-2, and progressive disease after receiving at least one systemic chemotherapy or within 12 months of neoadjuvant or adjuvant chemotherapy or were ineligible for cisplatin. The selected regimen determined in the initial part of the study was continuous once daily 8 mg/day oral erdafitinib in 28-day cycles, with provision for pharmacodynamically guided uptitration to 9 mg/day (8 mg/day UpT). The primary endpoint was investigator-assessed confirmed objective response rate according to Response Evaluation Criteria In Solid Tumors version 1.1. Efficacy and safety were analysed in all treated patients who received at least one dose of erdafitinib. This is the final analysis of this study. This study is registered with ClinicalTrials.gov, NCT02365597.

FINDINGS

Between May 25, 2015, and Aug 9, 2018, 2328 patients were screened, of whom 212 were enrolled and 101 were treated with the selected erdafitinib 8 mg/day UpT regimen. The data cutoff date for this analysis was Aug 9, 2019. Median efficacy follow-up was 24·0 months (IQR 22·7-26·6). The investigator-assessed objective response rate for patients treated with the selected erdafitinib regimen was 40 (40%; 95% CI 30-49) of 101 patients. The safety profile remained similar to that in the primary analysis, with no new safety signals reported with longer follow-up. Grade 3-4 treatment-emergent adverse events of any causality occurred in 72 (71%) of 101 patients. The most common grade 3-4 treatment-emergent adverse events of any cause were stomatitis (in 14 [14%] of 101 patients) and hyponatraemia (in 11 [11%]). There were no treatment-related deaths.

INTERPRETATION

With longer follow-up, treatment with the selected regimen of erdafitinib showed consistent activity and a manageable safety profile in patients with locally advanced or metastatic urothelial carcinoma and prespecified FGFR alterations.

FUNDING

Janssen Research & Development.

Impact of Hypofractionated Radiotherapy on Patient-reported Outcomes in Prostate Cancer: Results up to 5 yr in the CHHiP trial (CRUK/06/016)

BACKGROUND

Moderate hypofractionation is the recommended standard of care for localised prostate cancer following the results of trials including Conventional or Hypofractionated High Dose Intensity Modulated Radiotherapy in Prostate Cancer (CHHiP). Evaluation of long-term patient-reported outcomes (PROs) is important to confirm safety and enhance patient information.

OBJECTIVE

To determine whether 5-yr PROs from the CHHiP quality of life (QoL) substudy confirm 2-yr findings and assess patterns over follow-up.

DESIGN, SETTING, AND PARTICIPANTS

A phase III randomised controlled trial recruited from 2002 to 2011. The QoL substudy completed accrual in 2009; participants were followed up to 5 yr after radiotherapy. Analyses used data snapshot taken on August 26, 2016. A total of 71 radiotherapy centres were included in the study (UK, Republic of Ireland, Switzerland, and New Zealand); all 57 UK centres participated in the QoL substudy. CHHiP recruited 3216 men with localised prostate cancer (cT1b-T3aN0M0).

INTERVENTION

Conventional (74 Gy/37 fractions/7.4 wk) or hypofractionated radiotherapy (60 Gy/20 fractions/4 wk or 57 Gy/19 fractions/3.8 wk) was delivered with intensity-modulated techniques.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

University of California Los Angeles Prostate Cancer Index, Short Form 36 and Functional Assessment of Cancer Therapy-Prostate, or Expanded Prostate Cancer Index Composite and Short Form 12 questionnaires were administered at baseline, before radiotherapy, at 10 wk, and at 6, 12, 18, 24, 36, 48, and 60 mo after radiotherapy. The QoL primary endpoint was overall bowel bother.

RESULTS AND LIMITATIONS

The QoL substudy recruited 2100 patients; 1141 5-yr forms were available from 1957 patients still alive (58%). There were no statistically significant differences in 5-yr prevalence of overall "moderate or big" bowel bother: 19/349 (5.4%), 29/381 (7.6%), and 21/393 (5.3%) for 74, 60, and 57 Gy, respectively; overall urinary or sexual bother at 5 yr was similar between schedules. Bowel and urinary symptoms remained stable from 2 to 5 yr for all schedules. Some evidence of worsening overall sexual bother from baseline to 5 yr was less likely in the hypofractionated schedules compared with 74 Gy (odds ratios for increase in bother score vs 74 Gy: 0.55 [0.30-0.99], p = 0.009 for 60 Gy, and 0.52 [0.29-0.94], p = 0.004 for 57 Gy). General QoL scores were similar between schedules at 5 yr.

CONCLUSIONS

Longer follow-up confirms earlier findings, with similar patient-reported bowel, urinary, and sexual problems between schedules overall. The continued low incidence of moderate or high bother confirms that moderate hypofractionation should be the standard of care for intermediate-risk localised prostate cancer.

PATIENT SUMMARY

We looked at patient-reported outcomes up to 5 yr after treatment in a trial of different radiotherapy schedules for prostate cancer. The findings confirmed that shorter radiotherapy schedules were as safe as standard radiotherapy in terms of bowel, urinary, and sexual problems. TAKE  HOME MESSAGE: Bowel, urinary, and sexual symptoms were similar between schedules up to 5 yr. The continued low incidence of moderate/high bother confirms that moderate hypofractionated radiotherapy should be considered the standard of care for men with intermediate-risk prostate cancer.

Estimates of Alpha/Beta (α/β) Ratios for Individual Late Rectal Toxicity Endpoints: An Analysis of the CHHiP Trial

PURPOSE

Changes in fraction size of external beam radiation therapy exert nonlinear effects on subsequent toxicity. Commonly described by the linear-quadratic model, fraction size sensitivity of normal tissues is expressed by the α/β ratio. We sought to study individual α/β ratios for different late rectal effects after prostate external beam radiation therapy.

METHODS AND MATERIALS

The CHHiP trial (ISRCTN97182923) randomized men with nonmetastatic prostate cancer 1:1:1 to 74 Gy/37 fractions (Fr), 60 Gy/20 Fr, or 57 Gy/19 Fr. Patients in the study had full dosimetric data and zero baseline toxicity. Toxicity scales were amalgamated to 6 bowel endpoints: bleeding, diarrhea, pain, proctitis, sphincter control, and stricture. Lyman-Kutcher-Burman models with or without equivalent dose in 2 Gy/Fr correction were log-likelihood fitted by endpoint, estimating α/β ratios. The α/β ratio estimate sensitivity was assessed using sequential inclusion of dose modifying factors (DMFs): age, diabetes, hypertension, inflammatory bowel or diverticular disease (IBD/diverticular), and hemorrhoids. 95% confidence intervals (CIs) were bootstrapped. Likelihood ratio testing of 632 estimator log-likelihoods compared the models.

RESULTS

Late rectal α/β ratio estimates (without DMF) ranged from bleeding (G1 + α/β = 1.6 Gy; 95% CI, 0.9-2.5 Gy) to sphincter control (G1 + α/β = 3.1 Gy; 95% CI, 1.4-9.1 Gy). Bowel pain modelled poorly (α/β, 3.6 Gy; 95% CI, 0.0-840 Gy). Inclusion of IBD/diverticular disease as a DMF significantly improved fits for stool frequency G2+ (P = .00041) and proctitis G1+ (P = .00046). However, the α/β ratios were similar in these no-DMF versus DMF models for both stool frequency G2+ (α/β 2.7 Gy vs 2.5 Gy) and proctitis G1+ (α/β 2.7 Gy vs 2.6 Gy). Frequency-weighted averaging of endpoint α/β ratios produced: G1 + α/β ratio = 2.4 Gy; G2 + α/β ratio = 2.3 Gy.

CONCLUSIONS

We estimated α/β ratios for several common late adverse effects of rectal radiation therapy. When comparing dose-fractionation schedules, we suggest using late a rectal α/β ratio ≤ 3 Gy.

4 Gy versus 24 Gy radiotherapy for follicular and marginal zone lymphoma (FoRT): long-term follow-up of a multicentre, randomised, phase 3, non-inferiority trial

BACKGROUND

The optimal radiotherapy dose for indolent non-Hodgkin lymphoma is uncertain. We aimed to compare 24 Gy in 12 fractions (representing the standard of care) with 4 Gy in two fractions (low-dose radiation).

METHODS

FoRT (Follicular Radiotherapy Trial) is a randomised, multicentre, phase 3, non-inferiority trial at 43 study centres in the UK. We enrolled patients (aged >18 years) with indolent non-Hodgkin lymphoma who had histological confirmation of follicular lymphoma or marginal zone lymphoma requiring radical or palliative radiotherapy. No limit on performance status was stipulated, and previous chemotherapy or radiotherapy to another site was permitted. Radiotherapy target sites were randomly allocated (1:1) either 24 Gy in 12 fractions or 4 Gy in two fractions using minimisation and stratified by histology, treatment intent, and study centre. Randomisation was centralised through the Cancer Research UK and University College London Cancer Trials Centre. Patients, treating clinicians, and investigators were not masked to random assignments. The primary endpoint was time to local progression in the irradiated volume based on clinical and radiological evaluation and analysed on an intention-to-treat basis. The non-inferiority threshold aimed to exclude the chance that 4 Gy was more than 10% inferior to 24 Gy in terms of local control at 2 years (HR 1·37). Safety (in terms of adverse events) was analysed in patients who received any radiotherapy and who returned an adverse event form. FoRT is registered with ClinicalTrials.gov, NCT00310167, and the ISRCTN Registry, ISRCTN65687530, and this report represents the long-term follow-up.

FINDINGS

Between April 7, 2006, and June 8, 2011, 614 target sites in 548 patients were randomly assigned either 24 Gy in 12 fractions (n=299) or 4 Gy in two fractions (n=315). At a median follow-up of 73·8 months (IQR 61·9-88·0), 117 local progression events were recorded, 27 in the 24 Gy group and 90 in the 4 Gy group. The 2-year local progression-free rate was 94·1% (95% CI 90·6-96·4) after 24 Gy and 79·8% (74·8-83·9) after 4 Gy; corresponding rates at 5 years were 89·9% (85·5-93·1) after 24 Gy and 70·4% (64·7-75·4) after 4 Gy (hazard ratio 3·46, 95% CI 2·25-5·33; p<0·0001). The difference at 2 years remains outside the non-inferiority margin of 10% at -13·0% (95% CI -21·7 to -6·9). The most common events at week 12 were alopecia (19 [7%] of 287 sites with 24 Gy vs six [2%] of 301 sites with 4 Gy), dry mouth (11 [4%] vs five [2%]), fatigue (seven [2%] vs five [2%]), mucositis (seven [2%] vs three [1%]), and pain (seven [2%] vs two [1%]). No treatment-related deaths were reported.

INTERPRETATION

Our findings at 5 years show that the optimal radiotherapy dose for indolent lymphoma is 24 Gy in 12 fractions when durable local control is the aim of treatment.

FUNDING

Cancer Research UK.

Brentuximab Vedotin for Treating Relapsed or Refractory CD30-Positive Cutaneous T-Cell Lymphoma: An Evidence Review Group Perspective of a NICE Single Technology Appraisal

As part of the single technology appraisal process, the National Institute for Health and Care Excellence invited Takeda UK Ltd to submit clinical- and cost-effectiveness evidence for brentuximab vedotin (BV) for treating relapsed or refractory CD30-positive (CD30+) cutaneous T-cell lymphoma (CTCL). The Liverpool Reviews and Implementation Group at the University of Liverpool was commissioned to act as the evidence review group (ERG). This article summarises the ERG's review of the company's submission for BV and the appraisal committee (AC) decision. The principal clinical evidence was derived from a subgroup of patients with advanced-stage CD30+ mycosis fungoides (MF) or primary cutaneous anaplastic large-cell lymphoma (pcALCL) in the phase III ALCANZA randomised controlled trial (RCT). This trial compared BV versus physician's choice (PC) of methotrexate or bexarotene. Evidence from three observational studies was also presented, which included patients with other CTCL subtypes. The ERG's main concerns with the clinical evidence were the lack of RCT evidence for CTCL subtypes other than MF or pcALCL, lack of robust overall survival data (data were immature and confounded by subsequent treatment and treatment crossover on disease progression) and lack of conclusive results from analyses of health-related quality-of-life data. The ERG noted that many areas of uncertainty in the cost-effectiveness analysis were related to the clinical data, arising from the rarity of the condition and its subtypes and the complexity of the treatment pathway. The ERG highlighted that the inclusion of allogeneic stem-cell transplant (alloSCT) as an option in the treatment pathway was based on weak evidence and generated more uncertainty in a disease area that, because of its rarity and diversity, was already highly uncertain. The ERG also lacked confidence in the company's modelling of the post-progression pathway and was concerned that it may not produce reliable results. Results from the company's base-case comparison (including a simple discount patient access scheme [PAS] for BV) showed that treatment with BV dominated PC. The ERG's revisions and scenario analyses highlighted the high level of uncertainty around the company base-case cost-effectiveness results, ranging from BV dominating PC to an incremental cost-effectiveness ratio per quality-adjusted life-year gained of £494,981. The AC concluded that it was appropriate to include alloSCT in the treatment pathway even though data were limited. The AC recommended BV as an option for treating CD30+ CTCL after at least one systemic therapy in adults if they have MF, stage IIB or higher pcALCL or Sézary syndrome and if the company provides BV according to the commercial arrangement (i.e. simple discount PAS).

Prostate Cancer Radiation Therapy Recommendations in Response to COVID-19

PURPOSE

During a global pandemic, the benefit of routine visits and treatment of patients with cancer must be weighed against the risks to patients, staff, and society. Prostate cancer is one of the most common cancers radiation oncology departments treat, and efficient resource utilization is essential in the setting of a pandemic. Herein, we aim to establish recommendations and a framework by which to evaluate prostate radiation therapy management decisions.

METHODS AND MATERIALS

Radiation oncologists from the United States and the United Kingdom rapidly conducted a systematic review and agreed upon recommendations to safely manage patients with prostate cancer during the COVID-19 pandemic. A RADS framework was created: remote visits, and avoidance, deferment, and shortening of radiation therapy was applied to determine appropriate approaches.

RESULTS

Recommendations were provided by the National Comprehensive Cancer Network risk group regarding clinical node-positive, postprostatectomy, oligometastatic, and low-volume M1 disease. Across all prostate cancer stages, telemedicine consultations and return visits were recommended when resources/staff available. Delays in consultations and return visits of between 1 and 6 months were deemed safe based on stage of disease. Treatment can be avoided or delayed until safe for very low, low, and favorable intermediate-risk disease. Unfavorable intermediate-risk, high-risk, clinical node-positive, recurrence postsurgery, oligometastatic, and low-volume M1 disease can receive neoadjuvant hormone therapy for 4 to 6 months as necessary. Ultrahypofractionation is preferred for localized, oligometastatic, and low-volume M1, and moderate hypofractionation is preferred for postprostatectomy and clinical node positive disease. Salvage is preferred to adjuvant radiation.

CONCLUSIONS

Resources can be reduced for all identified stages of prostate cancer. The RADS (remote visits, and avoidance, deferment, and shortening of radiation therapy) framework can be applied to other disease sites to help with decision making in a global pandemic.

PIVOTALboost: A phase III randomised controlled trial of prostate and pelvis versus prostate alone radiotherapy with or without prostate boost (CRUK/16/018)

•PIVOTALboost evaluates benefits/toxicity of pelvic node RT and focal boost dose escalation.•Unfavourable intermediate/high risk and bulky local disease are most likely to benefit.•Functional MRI imaging is used to select patients for different types of dose escalation.•HDR brachytherapy or focal dose escalation with IMRT are used as options.•Training and support is provided to reduce variations of contouring and radiotherapy planning.•The trial is recruiting patients in 38 radiotherapy centres through the UK.

Ten-Year Results of FAST: A Randomized Controlled Trial of 5-Fraction Whole-Breast Radiotherapy for Early Breast Cancer

PURPOSE

Previous studies of hypofractionated adjuvant whole-breast radiotherapy for early breast cancer established a 15- or 16-fraction (fr) regimen as standard. The FAST Trial (CRUKE/04/015) evaluated normal tissue effects (NTE) and disease outcomes after 5-fr regimens. Ten-year results are presented.

METHODS

Women ≥ 50 years of age with low-risk invasive breast carcinoma (pT1-2 pN0) were randomly assigned to 50 Gy/25 fr (5 weeks) or 30 or 28.5 Gy in 5 once-weekly fr of 6.0 or 5.7 Gy. The primary end point was change in photographic breast appearance at 2 and 5 years; secondary end points were physician assessments of NTE and local tumor control. Odds ratios (ORs) from longitudinal analyses compared regimens.

RESULTS

A total of 915 women were recruited from 18 UK centers (2004-2007). Five-year photographs were available for 615/862 (71%) eligible patients. ORs for change in photographic breast appearance were 1.64 (95% CI, 1.08 to 2.49; P = .019) for 30 Gy and 1.10 (95% CI, 0.70 to 1.71; P = .686) for 28.5 Gy versus 50 Gy. α/β estimate for photographic end point was 2.7 Gy (95% CI, 1.5 to 3.9 Gy), giving a 5-fr schedule of 28 Gy (95% CI, 26 to 30 Gy) estimated to be isoeffective with 50 Gy/25 fr. ORs for any moderate/marked physician-assessed breast NTE (shrinkage, induration, telangiectasia, edema) were 2.12 (95% CI, 1.55 to 2.89; P < .001) for 30 Gy and 1.22 (95% CI, 0.87 to 1.72; P = .248) for 28.5 Gy versus 50 Gy. With 9.9 years median follow-up, 11 ipsilateral breast cancer events (50 Gy: 3; 30 Gy: 4; 28.5 Gy: 4) and 96 deaths (50 Gy: 30; 30 Gy: 33; 28.5 Gy: 33) have occurred.

CONCLUSION

At 10 years, there was no significant difference in NTE rates after 28.5 Gy/5 fr compared with 50 Gy/25 fr, but NTE were higher after 30 Gy/5 fr. Results confirm the published 3-year findings that a once-weekly 5-fr schedule of whole-breast radiotherapy can be identified that appears to be radiobiologically comparable for NTE to a conventionally fractionated regimen.

Prostate Cancer Radiation Therapy Recommendations in Response to COVID-19

PURPOSE

During a global pandemic, the benefit of routine visits and treatment of patients with cancer must be weighed against the risks to patients, staff, and society. Prostate cancer is one of the most common cancers radiation oncology departments treat, and efficient resource utilization is essential in the setting of a pandemic. Herein, we aim to establish recommendations and a framework by which to evaluate prostate radiation therapy management decisions.

METHODS AND MATERIALS

Radiation oncologists from the United States and the United Kingdom rapidly conducted a systematic review and agreed upon recommendations to safely manage patients with prostate cancer during the COVID-19 pandemic. A RADS framework was created: remote visits, and avoidance, deferment, and shortening of radiation therapy was applied to determine appropriate approaches.

RESULTS

Recommendations were provided by the National Comprehensive Cancer Network risk group regarding clinical node-positive, postprostatectomy, oligometastatic, and low-volume M1 disease. Across all prostate cancer stages, telemedicine consultations and return visits were recommended when resources/staff available. Delays in consultations and return visits of between 1 and 6 months were deemed safe based on stage of disease. Treatment can be avoided or delayed until safe for very low, low, and favorable intermediate-risk disease. Unfavorable intermediate-risk, high-risk, clinical node-positive, recurrence postsurgery, oligometastatic, and low-volume M1 disease can receive neoadjuvant hormone therapy for 4 to 6 months as necessary. Ultrahypofractionation is preferred for localized, oligometastatic, and low-volume M1, and moderate hypofractionation is preferred for postprostatectomy and clinical node positive disease. Salvage is preferred to adjuvant radiation.

CONCLUSIONS

Resources can be reduced for all identified stages of prostate cancer. The RADS (remote visits, and avoidance, deferment, and shortening of radiation therapy) framework can be applied to other disease sites to help with decision making in a global pandemic.

Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial

BACKGROUND

We aimed to identify a five-fraction schedule of adjuvant radiotherapy (radiation therapy) delivered in 1 week that is non-inferior in terms of local cancer control and is as safe as an international standard 15-fraction regimen after primary surgery for early breast cancer. Here, we present 5-year results of the FAST-Forward trial.

METHODS

FAST-Forward is a multicentre, phase 3, randomised, non-inferiority trial done at 97 hospitals (47 radiotherapy centres and 50 referring hospitals) in the UK. Patients aged at least 18 years with invasive carcinoma of the breast (pT1-3, pN0-1, M0) after breast conservation surgery or mastectomy were eligible. We randomly allocated patients to either 40 Gy in 15 fractions (over 3 weeks), 27 Gy in five fractions (over 1 week), or 26 Gy in five fractions (over 1 week) to the whole breast or chest wall. Allocation was not masked because of the nature of the intervention. The primary endpoint was ipsilateral breast tumour relapse; assuming a 2% 5-year incidence for 40 Gy, non-inferiority was predefined as ≤1·6% excess for five-fraction schedules (critical hazard ratio [HR] of 1·81). Normal tissue effects were assessed by clinicians, patients, and from photographs. This trial is registered at isrctn.com, ISRCTN19906132.

FINDINGS

Between Nov 24, 2011, and June 19, 2014, we recruited and obtained consent from 4096 patients from 97 UK centres, of whom 1361 were assigned to the 40 Gy schedule, 1367 to the 27 Gy schedule, and 1368 to the 26 Gy schedule. At a median follow-up of 71·5 months (IQR 71·3 to 71·7), the primary endpoint event occurred in 79 patients (31 in the 40 Gy group, 27 in the 27 Gy group, and 21 in the 26 Gy group); HRs versus 40 Gy in 15 fractions were 0·86 (95% CI 0·51 to 1·44) for 27 Gy in five fractions and 0·67 (0·38 to 1·16) for 26 Gy in five fractions. 5-year incidence of ipsilateral breast tumour relapse after 40 Gy was 2·1% (1·4 to 3·1); estimated absolute differences versus 40 Gy in 15 fractions were -0·3% (-1·0 to 0·9) for 27 Gy in five fractions (probability of incorrectly accepting an inferior five-fraction schedule: p=0·0022 vs 40 Gy in 15 fractions) and -0·7% (-1·3 to 0·3) for 26 Gy in five fractions (p=0·00019 vs 40 Gy in 15 fractions). At 5 years, any moderate or marked clinician-assessed normal tissue effects in the breast or chest wall was reported for 98 of 986 (9·9%) 40 Gy patients, 155 (15·4%) of 1005 27 Gy patients, and 121 of 1020 (11·9%) 26 Gy patients. Across all clinician assessments from 1-5 years, odds ratios versus 40 Gy in 15 fractions were 1·55 (95% CI 1·32 to 1·83, p<0·0001) for 27 Gy in five fractions and 1·12 (0·94 to 1·34, p=0·20) for 26 Gy in five fractions. Patient and photographic assessments showed higher normal tissue effect risk for 27 Gy versus 40 Gy but not for 26 Gy versus 40 Gy.

INTERPRETATION

26 Gy in five fractions over 1 week is non-inferior to the standard of 40 Gy in 15 fractions over 3 weeks for local tumour control, and is as safe in terms of normal tissue effects up to 5 years for patients prescribed adjuvant local radiotherapy after primary surgery for early-stage breast cancer.

FUNDING

National Institute for Health Research Health Technology Assessment Programme.

Evaluation of erectile potency and radiation dose to the penile bulb using image guided radiotherapy in the CHHiP trial

BACKGROUND AND PURPOSE

The penile bulb (PB) dose may be critical in development of post prostate radiotherapy erectile dysfunction (ED). This study aimed to generate PB dose constraints based on dose-volume histograms (DVHs) in patients treated with prostate radiotherapy, and to identify clinical and dosimetric parameters that predict the risk of ED post prostate radiotherapy.

MATERIALS AND METHODS

Penile bulb DVHs were generated for 276 patients treated within the randomised IGRT substudy of the multicentre randomised trial, CHHiP. Incidence of ED in relation to dose and randomised IGRT groups were evaluated using Wilcoxon rank sum, Chi-squared test and atlases of complication incidence. Youden index was used to find dose-volume constraints that discriminated for ED. Multivariate analysis (MVA) of effect of dosimetry, clinical and patient-related variables was performed.

RESULTS

Reduced treatment margins using IGRT (IGRT-R) produced significantly reduced mean PB dose compared with standard margins (IGRT-S) (median: 25 Gy (IGRT-S) versus 11 Gy (IGRT-R); p < 0.0001). Significant difference in both mean (median: 23 Gy (ED) vs. 18 Gy (no ED); p = 0.011) and maximum (median: 59 Gy (ED) vs. 52 Gy (no ED); p = 0.018) PB doses between those with and without clinician reported ED were identified. Mean PB dose cut-point for ED was derived at around 20 Gy. On MVA, PB mean dose and age predicted for impotence.

CONCLUSION

PB dose appears predictive of post-radiotherapy ED with calculated threshold mean dose of around 20 Gy, substantially lower than published recommendations. IGRT-R enables favourable PB dosimetry and can be recommended provided prostate coverage is not compromised.

PIVOTALboost Trial contouring RTQA

373

Background: The PIVOTALboost trial (ISRCTN80146950) recruits patients with intermediate and high risk, localised prostate cancer; it tests the role of pelvic node radiotherapy and the effectiveness of a focal intra-prostate IMRT boost. Prior to opening to recruitment a contouring QA program was designed aiming to improve consistency in clinical outlining. Methods: Intra-prostatic boosting was a new treatment method for all but 3 trial centers. Guidelines for boost contouring and pelvic node outlining were circulated. Clinicians were sent two different cases with the clinical case description, biopsy details, the diagnostic pre-biopsy multi-parametric MRI (T2W and DWI sequences) and planning CT and MRI scans. They were asked to contour prostate, seminal vesicle (CTVp, CTVpsv), lymph node (CTVn) for 1 case and boost volume (GTVpb) for both cases. The 3 lead trial clinicians contoured the cases independently, agreed on gold standard outlines and criteria for failing the submission. Center’ benchmark case submissions were reviewed and standardized feedback forms returned to each clinician. General issues were addressed during a trial launch workshop. Results: There was good agreement of the contours for CTVp, CTVpsv and CTVn between the 3 lead clinicians for the gold standard; more discussions were required to agree GTVpb. Criteria for re-submission were: contours >6mm beyond or >3mm inside the superior and inferior level, included OARs, excluded SV base or extracapsular extension. In addition, for GTVpb, the wrong segment, extension outside CTVp, outlining abnormalities <5mm in diameter or a volume > or < 50% of the gold standard. 35 center and 54 clinicians submitted outlines: for CTVp/psv 24/54 failed, CTVn 14/54 failed, GTVpb 23/48 failed (6 investigators did not submit a volume). All center passed the re-submission; for the on trial outlining review, 9 centres have not recruited a patient for the on trial review process, 18 passed and 8 failed. Conclusions: Errors and inconsistencies were common in the benchmark outlining exercises for the trial. Individual feedback, guidelines and clinical support has reduced outlining variations without delaying the opening of the trial; it has helped to standardize contouring and engage clinicians in the trial process. Clinical trial information: 80146950.

Eight-year outcomes of a phase III randomized trial of conventional versus hypofractionated high-dose intensity modulated radiotherapy for prostate cancer (CRUK/06/016): Update from the CHHiP Trial

325

Background: CHHiP is a non-inferiority trial to determine efficacy and safety of hypofractionated radiotherapy for localised prostate cancer (PCa). Five year results indicated that moderate hypofractionation of 60 Gray (Gy)/20 fractions (f) was non-inferior to 74Gy/37f (Lancet Oncology, 2016). Moderate hypofractionation is now an international standard of care but with patients remaining at risk of recurrence for many years, information on long-term outcomes is important. Here we report pre-planned analysis of 8 year outcomes. Methods: Between October 2002 and June 2011, 3216 men with node negative T1b-T3a localised PCa with risk of seminal vesical involvement ≤30% were randomised (1:1:1 ratio) to 74Gy/37f (control), 60Gy/20f or 57Gy/19f. Androgen deprivation began at least 3 months prior to radiotherapy (RT) and continued until end of RT. The primary endpoint was time to biochemical failure (Phoenix consensus guidelines) or clinical failure (BCF). The non-inferiority design specified a critical hazard ratio (HR) of 1.208 for each hypofractionated schedule compared to 74Gy/37f. Late toxicity was assessed at 5 years by RTOG and LENT-SOM scales. Analysis was by intention-to-treat. Results: With a median follow up of 9.2 years, 8 year BCF-free rates (95% CI) were 74Gy: 80.6% (77.9%, 83.0%); 60Gy: 83.7% (81.2%, 85.9%) and 57Gy: 78.5% (75.8%, 81.0%). For 60Gy/20f, non-inferiority was confirmed: HR60=0.84 (90% CI 0.71, 0.99). For 57Gy/19f, non-inferiority could not be declared: HR57=1.17 (90% CI 1.00, 1.37). Clinician assessments of late toxicity were similar across groups. At 5 years, RTOG grade≥2 (G2+) bowel toxicity was observed in 14/879 (1.6%), 18/908 (2.0%) and 17/904 (1.9%) of the 74Gy, 60Gy and 57Gy groups respectively. RTOG G2+ bladder toxicity was observed in 17/879 (1.9%), 14/908 (1.5%) and 17/904 (1.9%) of the 74Gy, 60Gy and 57Gy groups respectively. Conclusions: With BCF rates over 80%, long-term follow-up confirms that 60Gy/20f is non-inferior to 74Gy/37f. Late side effects were very low across all groups. These results support the continued use of 60Gy/20f as standard of care for men with localised PCa. Clinical trial information: 97182923.

Patterns of use of chemotherapy with radiotherapy in the treatment of muscle-invasive bladder cancer: Data from the RAIDER randomized trial of adaptive radiotherapy

503

Background: Level 1 evidence exists for the use of both neoadjuvant chemotherapy (NAC) and concomitant radiosensitization (CRS) to improve outcomes in patients receiving radical radiotherapy (RT) for muscle invasive bladder cancer, but uptake has been patchy. We report here the current patterns of usage in an ongoing trial of adaptive radiotherapy. Methods: RAIDER is an international randomized phase II trial recruiting patients with unifocal T2-T4a urothelial carcinoma of the bladder suitable for RT (ISCRTN:26779187). Patients are randomized in a 1:1:2 ratio to one of 3 arms: Standard whole bladder RT (control); Standard dose adaptive tumour focused RT; Dose escalated (DE) adaptive tumour boost RT. Standard dose patients are treated to either 64Gy/32f or 55Gy/20f and DE patients to 70Gy in 32f or 60Gy in 20f. Patients are encouraged to receive NAC and CRS. The primary endpoint is the rate of late toxicity 6-18 months post treatment in arm 3, with secondary endpoints of patient reported and disease related outcomes. Results: To August 2019, 285 patients had been recruited. Median age is 72 years (IQR 67-79). Stage of disease is T2 79%, T3 19%, T4 2%; 19% have hydronephrosis. Patients receiving NAC were more likely to be PS 0 at trial entry (70% v 45%). Variation in frequency of CRS use is seen across sites, with some offering to >90% of participants and some <50%. Data on NAC and CRS use is available for 249 patients recruited to date is shown in table. Conclusions: In this ongoing clinical trial the majority of patients are receiving NAC and/or CRS. However, uptake is not universal with ~30% of patients not receiving low dose CRS, including some who have received NAC. Clinical trial information: 26779187. [Table: see text]

Fragmentation of Single-Particle Strength around the Doubly Magic Nucleus ^{132}Sn and the Position of the 0f_{5/2} Proton-Hole State in ^{131}In

Spectroscopic factors of neutron-hole and proton-hole states in ^{131}Sn and ^{131}In, respectively, were measured using one-nucleon removal reactions from doubly magic ^{132}Sn at relativistic energies. For ^{131}In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5/2^{-} state at 3275(50) keV to the known 1/2^{-} level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of single-hole strength in ^{131}Sn and ^{131}In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling model and to experimental information for single-hole states in the stable doubly magic nucleus ^{208}Pb.

Olaparib in patients with metastatic castration-resistant prostate cancer with DNA repair gene aberrations (TOPARP-B): a multicentre, open-label, randomised, phase 2 trial

BACKGROUND

Metastatic castration-resistant prostate cancer is enriched in DNA damage response (DDR) gene aberrations. The TOPARP-B trial aims to prospectively validate the association between DDR gene aberrations and response to olaparib in metastatic castration-resistant prostate cancer.

METHODS

In this open-label, investigator-initiated, randomised phase 2 trial following a selection (or pick-the-winner) design, we recruited participants from 17 UK hospitals. Men aged 18 years or older with progressing metastatic castration-resistant prostate cancer previously treated with one or two taxane chemotherapy regimens and with an Eastern Cooperative Oncology Group performance status of 2 or less had tumour biopsies tested with targeted sequencing. Patients with DDR gene aberrations were randomly assigned (1:1) by a computer-generated minimisation method, with balancing for circulating tumour cell count at screening, to receive 400 mg or 300 mg olaparib twice daily, given continuously in 4-week cycles until disease progression or unacceptable toxicity. Neither participants nor investigators were masked to dose allocation. The primary endpoint of confirmed response was defined as a composite of all patients presenting with any of the following outcomes: radiological objective response (as assessed by Response Evaluation Criteria in Solid Tumors 1.1), a decrease in prostate-specific antigen (PSA) of 50% or more (PSA50) from baseline, or conversion of circulating tumour cell count (from ≥5 cells per 7·5 mL blood at baseline to <5 cells per 7·5 mL blood). A confirmed response in a consecutive assessment after at least 4 weeks was required for each component. The primary analysis was done in the evaluable population. If at least 19 (43%) of 44 evaluable patients in a dose cohort responded, then the dose cohort would be considered successful. Safety was assessed in all patients who received at least one dose of olaparib. This trial is registered at ClinicalTrials.gov, NCT01682772. Recruitment for the trial has completed and follow-up is ongoing.

FINDINGS

711 patients consented for targeted screening between April 1, 2015, and Aug 30, 2018. 161 patients had DDR gene aberrations, 98 of whom were randomly assigned and treated (49 patients for each olaparib dose), with 92 evaluable for the primary endpoint (46 patients for each olaparib dose). Median follow-up was 24·8 months (IQR 16·7-35·9). Confirmed composite response was achieved in 25 (54·3%; 95% CI 39·0-69·1) of 46 evaluable patients in the 400 mg cohort, and 18 (39·1%; 25·1-54·6) of 46 evaluable patients in the 300 mg cohort. Radiological response was achieved in eight (24·2%; 11·1-42·3) of 33 evaluable patients in the 400 mg cohort and six (16·2%; 6·2-32·0) of 37 in the 300 mg cohort; PSA50 response was achieved in 17 (37·0%; 23·2-52·5) of 46 and 13 (30·2%; 17·2-46·1) of 43; and circulating tumour cell count conversion was achieved in 15 (53·6%; 33·9-72·5) of 28 and 13 (48·1%; 28·7-68·1) of 27. The most common grade 3-4 adverse event in both cohorts was anaemia (15 [31%] of 49 patients in the 300 mg cohort and 18 [37%] of 49 in the 400 mg cohort). 19 serious adverse reactions were reported in 13 patients. One death possibly related to treatment (myocardial infarction) occurred after 11 days of treatment in the 300 mg cohort.

INTERPRETATION

Olaparib has antitumour activity against metastatic castration-resistant prostate cancer with DDR gene aberrations, supporting the implementation of genomic stratification of metastatic castration-resistant prostate cancer in clinical practice.

FUNDING

Cancer Research UK, AstraZeneca, Prostate Cancer UK, the Prostate Cancer Foundation, the Experimental Cancer Medicine Centres Network, and the National Institute for Health Research Biomedical Research Centres.

A randomised assessment of image guided radiotherapy within a phase 3 trial of conventional or hypofractionated high dose intensity modulated radiotherapy for prostate cancer

BACKGROUND AND PURPOSE

Image-guided radiotherapy (IGRT) improves treatment set-up accuracy and provides the opportunity to reduce target volume margins. We introduced IGRT methods using standard (IGRT-S) or reduced (IGRT-R) margins in a randomised phase 2 substudy within CHHiP trial. We present a pre-planned analysis of the impact of IGRT on dosimetry and acute/late pelvic side effects using gastrointestinal and genitourinary clinician and patient-reported outcomes (PRO) and evaluate efficacy.

MATERIALS AND METHODS

CHHiP is a randomised phase 3, non-inferiority trial for men with localised prostate cancer. 3216 patients were randomly assigned to conventional (74 Gy in 2 Gy/fraction (f) daily) or moderate hypofractionation (60 or 57 Gy in 3 Gy/f daily) between October 2002 and June 2011. The IGRT substudy included a second randomisation assigning to no-IGRT, IGRT-S (standard CTV-PTV margins), or IGRT-R (reduced CTV-PTV margins). Primary substudy endpoint was late RTOG bowel and urinary toxicity at 2 years post-radiotherapy.

RESULTS

Between June 2010 to July 2011, 293 men were recruited from 16 centres. Median follow-up is 56.9(IQR 54.3-60.9) months. Rectal and bladder dose-volume and surface percentages were significantly lower in IGRT-R compared to IGRT-S group; (p < 0.0001). Cumulative proportion with RTOG grade ≥ 2 toxicity reported to 2 years for bowel was 8.3(95% CI 3.2-20.7)%, 8.3(4.7-14.6)% and 5.8(2.6-12.4)% and for urinary 8.4(3.2-20.8)%, 4.6(2.1-9.9)% and 3.9(1.5-9.9)% in no IGRT, IGRT-S and IGRT-R groups respectively. In an exploratory analysis, treatment efficacy appeared similar in all three groups.

CONCLUSION

Introduction of IGRT was feasible in a national randomised trial and IGRT-R produced dosimetric benefits. Overall side effect profiles were acceptable in all groups but lowest with IGRT and reduced margins.

ISRCTN

97182923.

TOPARP-B: A phase II randomized trial of the poly(ADP)-ribose polymerase (PARP) inhibitor olaparib for metastatic castration resistant prostate cancers (mCRPC) with DNA damage repair (DDR) alterations

5005

Background: We previously reported the antitumor activity of olaparib (400mg BID) against molecularly unselected mCRPC (TOPARP-A; Mateo et al NEJM 2015). We now report TOPARP-B, a phase II trial for patients with mCRPC preselected for putatively pathogenic DDR alterations. Methods: Patients with mCRPC progressing after ≥ 1 taxane chemotherapy underwent targeted sequencing of tumor biopsies and were deemed eligible when alterations (germline or somatic; mono- or bi-allelic) in any DDR gene were detected. Patients were randomized 1:1 under a “pick-the-winner” design to 400mg or 300mg of olaparib BID, aiming to exclude ≤30% response rate (RR) in either arm. The primary endpoint RR was defined as radiological response (RECIST 1.1) and/or PSA50% fall and/or CTC count conversion (Cellsearch; ≥5 to < 5), confirmed after 4-weeks. Analyses of RR per gene alteration subgroup was pre-planned. Secondary endpoints included progression-free survival (PFS), tolerability. Results: Overall, 98 patients (median age 67.6y) were randomized, with 92 patients treated and evaluable for the primary endpoint (70 RECIST-evaluable; 89 PSA50%-evaluable; 55 CTC-evaluable). All had progressed on ADT; 99% were post-docetaxel, 90% post-abiraterone/enzalutamide, 38% post-cabazitaxel. The overall RR was 54% (95%CI 39-69%, meeting threshold for primary endpoint) in the 400mg cohort and 37% (95%CI 23-53%) in the 300mg cohort. With a median follow-up of 17.6 months (mo), the overall median PFS (mPFS) was 5.4 mo. Subgroup analyses per altered gene identified indicated response rates for: BRCA1/2 of 80% (24/30; mPFS 8.1mo); PALB2 57% (4/7; mPFS 5.3mo); ATM 37% (7/19; mPFS 6.1mo); CDK12 25% (5/20; mPFS 2.9mo); others [ATRX, CHEK1, CHEK2, FANCA, FANCF, FANCG, FANCI, FANCM, RAD50, WRN] 20% (4/20; mPFS 2.8mo). The highest PSA50% response rates were observed in the BRCA1/2 (22/30; 73%) and PALB2 (4/6; 67%) subgroups. Conclusions: Olaparib has antitumor activity against heavily pre-treated mCRPC with DDR gene defects, with BRCA1/2 aberrant tumors being most sensitive but with confirmed responses in patients with other DDR alterations. Clinical trial information: NCT01682772.

Toxicity and Patient-Reported Outcomes of a Phase 2 Randomized Trial of Prostate and Pelvic Lymph Node Versus Prostate only Radiotherapy in Advanced Localised Prostate Cancer (PIVOTAL)

PURPOSE

To establish the toxicity profile of high-dose pelvic lymph node intensity-modulated radiation therapy (IMRT) and to assess whether it is safely deliverable at multiple centers.

METHODS AND MATERIALS

In this phase 2 noncomparative multicenter trial, 124 patients with locally advanced, high-risk prostate cancer were randomized between prostate-only IMRT (PO) (74 Gy/37 fractions) and prostate and pelvic lymph node IMRT (P&P; 74 Gy/37 fractions to prostate, 60 Gy/37 fractions to pelvis). The primary endpoint was acute lower gastrointestinal (GI) Radiation Therapy Oncology Group (RTOG) toxicity at week 18, aiming to exclude a grade 2 or greater (G2+) toxicity-free rate of 80% in the P&P group. Key secondary endpoints included patient-reported outcomes and late toxicity.

RESULTS

One hundred twenty-four participants were randomized (62 PO, 62 P&P) from May 2011 to March 2013. Median follow-up was 37.6 months (interquartile range [IQR], 35.4-38.9 months). Participants had a median age of 69 years (IQR, 64-74 years) and median diagnostic prostate-specific androgen level of 21.6 ng/mL (IQR, 11.8-35.1 ng/mL). At week 18, G2+ lower GI toxicity-free rates were 59 of 61 (96.7%; 90% confidence interval [CI], 90.0-99.4) for the PO group and 59 of 62 (95.2%; 90% CI, 88.0-98.7) for the P&P group. Patients in both groups reported similarly low Inflammatory Bowel Disease Questionnaire symptoms and Vaizey incontinence scores. The largest difference occurred at week 6 with 4 of 61 (7%) and 16 of 61 (26%) PO and P&P patients, respectively, experiencing G2+ toxicity. At 2 years, the cumulative proportion of RTOG G2+ GI toxicity was 16.9% (95% CI, 8.9%-30.9%) for the PO group and 24.0% (95% CI, 8.4%-57.9%) for the P&P group; in addition, RTOG G2+ bladder toxicity was 5.1% (95% CI, 1.7%-14.9%) for the PO group and 5.6% (95% CI, 1.8%-16.7%) for the P&P group.

CONCLUSIONS

PIVOTAL demonstrated that high-dose pelvic lymph node IMRT can be delivered at multiple centers with a modest side effect profile. Although safety data from the present study are encouraging, the impact of P&P IMRT on disease control remains to be established.

Hypofractionated dose painting IMRT using 20 fractions for intermediate to high-risk localized prostate cancer: Two-year outcome data (BIOPROP20, NCT02125175)

59

Background: Prostate dose painting (boosting intra-prostatic tumour volumes) may improve biochemical relapse-free survival similar to whole organ dose-escalation without the associated increased toxicity. We present a pre-defined secondary endpoint of 2 year outcome for patients at one of two UK centres in a phase II trial (BIOPROP20) on dose-painting radiotherapy for intermediate to high risk patients treated with 60Gy/20# and concurrent 68Gy boost. Methods: Pinnacle software was used for VMAT planning and boost volumes were outlined by18F choline PET/CT and mpMRI. Patients with positive lymph nodes also had concurrent pelvic radiotherapy of 45Gy with boost to 50Gy. Patients were followed up until year 2 with PSA and toxicity scores. Results: Overall 56 patients were treated, 5 with pelvic radiotherapy. Median age and PSA was 67.5 years (range 50 - 77) and 10.0ng/ml (3.9 - 39.4). All patients had tumour volumes > 10mm diameter on pre-biopsy mpMRI. 13 and 43 patients had intermediate and high risk disease. Median % LN risk was 18% (15 - 40). ADT duration was 6 months, 2 years, and 3 years for 42, 5, and 9 patients. At the 2 year follow up review, no grade 3 late toxicity was observed. For prostate only dose painting, grade 2 GU and GI toxicity was noted in 6% and 2% respectively. For prostate and nodal dose painting, no grade 2 toxicity was noted. Median IPSS score was 5 and 9, and median PSA was 0.3 and 0.1, in the two groups respectively. 1 patient had biochemical and metastatic relapse at 18 months (prostate, pelvic nodes and bone metastasis) and 1 patient had died of unrelated disease. Conclusions: Prostate radiotherapy with hypofractionated dose painting schedule of 60Gy/20# with 68Gy boost to intra-prostatic lesions was well tolerated at 2 years follow up. Clinical trial information: NCT02125175. [Table: see text]

Pretrial outlining quality assurance in PIVITOLBoost

50

Background: PIVOTALBoost is a Phase III randomised controlled trial (CRUK/16/018) of radiotherapy to prostate and pelvic nodes versus prostate alone with or without prostate boost. To minimise impact of target volume delineation (TVD) variation on trial outcome, pre-trial radiotherapy quality assurance (RTQA) was implemented to identify and correct potential variations. Methods: Participating centres offering a prostate boost submitted two pre-accrual outlining benchmark cases: one with a central zone boost (GTVpb) only and another with GTVpb (peripheral zone), CTVp/psv and CTVn. A detailed outlining protocol and diagnostic information were provided to centres. Submitted outlines were compared to consensus volumes created by the trial management group (TMG). The TMG deemed the volumes acceptable or as having acceptable or unacceptable variation. Detailed feedback was provided for each submission. Unacceptable variations required resubmission. Results: 32 investigators submitted pre-trial outlines. GTVpb was the most incorrectly outlined volume; 22 (69%) outliners had unacceptable errors for case 2 GTVpb, 17 (53%) for case 1 GTVpb. Most common GTVpb error was inferior extent of lesion followed by incorrect lesion outlined. 12 (38%) of outliners had unacceptable errors for CTVp/psv, most commonly due to delineation at the prostate apex. 8 (25%) outliners had unacceptable CTVn mostly due to incorrect vessel delineation. Of 26 (81%) outliners required to resubmit at least 1 case, 3(12%) required a second resubmission due to unacceptable errors on first resubmission. Conclusions: The majority of pre-trial outlining submissions had unacceptable errors requiring resubmission of at least one case. This was predominantly due to boost delineation error which is a relatively new skill for prostate clinical oncologists in the UK. This suggests robust on-trial RTQA is imperative to minimise further variation. Clinical trial information: ISRCTN80146950.

Abstract GS4-05: Dose escalated simultaneous integrated boost radiotherapy for women treated by breast conservation surgery for early breast cancer: 3-year adverse effects in the IMPORT HIGH trial (CRUK/06/003)

Background

IMPORT HIGH is a randomised, multi-centre phase III trial testing dose escalated simultaneous integrated boost (SIB) against sequential boost each delivered by intensity modulated radiotherapy (IMRT) for early stage breast cancer with higher risk of local relapse. The primary endpoint was initially breast induration at 3 years, requiring 840 patients; accrual was extended (target 2568) with the new primary endpoint of local relapse. We report adverse effects (AE) at 3 years.

Methods

Women age ≥18 after breast conservation surgery for pT1-3 pN0-pN3a M0 invasive carcinoma were eligible. Randomisation was 1:1:1 between 40Gy/15F to whole breast (WB) + 16Gy/8F sequential photon boost to tumour bed (40+16Gy), 36Gy/15F to WB, 40Gy to partial breast + 48Gy (48Gy) or + 53Gy (53Gy) in 15F SIB to tumour bed. AEs were assessed annually by clinicians in all patients and in a planned sub-set (840) of patients by photographs at 3 years and by patients at 6 months, 1 and 3 years. AE scores were dichotomised as none/mild vs marked for photographs and none/mild vs moderate/marked for patients and clinicians. Fisher's exact tests compared groups; principal comparison (protocol-specified) between 53Gy and 48Gy (p&lt;0.01 defined as statistical significance).

Results

2617 women consented between 03/2009 and 09/2015 from 39 UK radiotherapy centres. Median follow-up was 49.1 (IQR 36.8-63.2) months. Median age was 49 (IQR 44-56); 9%, 38% & 53% were tumour grade 1, 2 & 3 respectively; 30% were node positive. 66% received chemotherapy and 73% endocrine therapy. 3-year AE data were available for 2017 clinician assessments, 641 photographs and 842 patient assessments. Proportions of patients with marked AEs were low overall. Rates of moderate/marked AEs at 3 years were broadly similar between the randomised groups; with a suggestion of a slightly increased risk for breast induration in 53Gy compared with control (borderline significance).

AE at 3 years 40+16Gy n(%)48Gy n(%)53Gy n(%)ClinicianBreast induration;N656668654None451 (69)483 (72)445 (68)Mild167 (25)141 (21)146 (22)Moderate32 (5)42 (6)56 (9)Marked6 (1)2 (1)7 (1)P-value 0.57010.0102  0.0443Breast shrinkage;N655669654None442 (68)472 (71)448 (69)Mild167 (26)161 (24)166 (25)Moderate40 (6)33 (5)35 (5)Marked6 (1)3 (1)5 (1)P-value 0.25410.5772  0.6373Breast distortion;N656669654None451 (69)464 (69)442 (68)Mild169 (26)170 (25)170 (26)Moderate33 (5)32 (5)38 (6)Marked3 (1)3 (1)4 (1)P-value 0.90310.4862  0.4113PatientChange in breast appearance;N287264285None38 (13)50 (19)58 (20)Mild164 (57)151 (57)142 (50)Moderate57 (20)45 (17)54 (19)Marked28 (10)18 (7)31 (11)P-value 0.14910.9992  0.1243PhotographChange in breast appearance;N218210213None183 (84)185 (88)177 (83)Mild25 (11)23 (11)32 (15)Marked10 (5)2 (1)4 (2)P-value 0.03610.1732  0.6853148Gy v 40+16Gy; 253Gy v 40+16Gy; 353Gy v 48Gy

Conclusions

These results represent the largest and most mature reported AE outcomes of breast SIB within a clinical trial. At 3 years, rates of moderate/marked AEs were similar between SIB IMRT and WB + sequential boost IMRT delivered over 3 and 4.5 weeks respectively.

Citation Format: Coles CE, Griffin CL, Kirby AM, Haviland JS, Titley JC, Benstead K, Brunt AM, Chan C, Ciurlionis L, Din OS, Donovan EM, Eaton DJ, Harnett AN, Hopwood P, Jefford ML, Jenkins PJ, Lee CE, McCormack M, Sherwin L, Syndikus I, Tsang Y, Twyman NI, Ventikaraman R, Wickers S, Wilcox MH, Bliss JM, Yarnold JR. Dose escalated simultaneous integrated boost radiotherapy for women treated by breast conservation surgery for early breast cancer: 3-year adverse effects in the IMPORT HIGH trial (CRUK/06/003) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS4-05.

Enhanced Electric Dipole Strength for the Weakly Bound States in ^{27}Ne

An enhanced low-energy electric dipole (E1) strength is identified for the weakly bound excited states of the neutron-rich isotope ^{27}Ne. The Doppler-shift lifetime measurements employing a combination of the γ-ray tracking array GRETINA, the plunger device, and the S800 spectrograph determine the lower limit of 0.030  e^{2} fm^{2} or 0.052 W.u. for the 1/2^{+}→3/2^{-}  E1 transition in ^{27}Ne, representing one of the strongest E1 strengths observed among the bound discrete states in this mass region. This value is at least 30 times larger than that measured for the 3/2^{-} decay to the 3/2_{gs}^{+} ground state. A comparison of the present results to large-scale shell-model calculations points to an important role of core excitations and deformation in the observed E1 enhancement, suggesting a novel example of the electric dipole modes manifested in weakly bound deformed systems.