STAMPEDE2 trial: A site survey of current patterns of care, access to imaging and treatment
HODA ABDEL-ATY,
United Kingdom
PO-1534
Abstract
STAMPEDE2 trial: A site survey of current patterns of care, access to imaging and treatment
Authors: Hoda Abdel-Aty1, Lorna O'Shea2, Claire Amos2, Louise C Brown2, Emily Grist2, Gerhardt Attard2, Noel Clarke3, William Cross4, Nicholas vas As1, Nicholas James1
1Institute of Cancer Research. The Royal Marsden NHS Foundation Trust, Radiotherapy and Imaging, London, United Kingdom; 2Institute of Clinical Trials & Methodology, MRC Clinical Trials Unit at UCL , London, United Kingdom; 3The Christie and Salford Royal NHS Foundation Trusts, Department of Urology, Manchester, United Kingdom; 4St James University Hospital, Leeds, Department of Urology , Leeds, United Kingdom
Show Affiliations
Hide Affiliations
Purpose or Objective
The STAMPEDE trial is a multi-arm multi-stage trial platform testing treatments in hormone-sensitive prostate cancer (HSPC). STAMPEDE2 trial has new comparisons investigating stereotactic ablative body radiotherapy (SABR), 177Lutetium-PSMA-617, and Abiraterone + Niraparib. We aim to determine current practice in relation to imaging and treatment, and explore the interest of STAMPEDE investigators to participate in STAMPEDE2.
Material and Methods
The survey was developed and circulated to 120 UK STAMPEDE sites in May 2022. Questions on access to SABR, 177Lutetium-PSMA-617, choice of systemic therapies and use of novel imaging (PET/CT and Whole-body MRI) were included. Sites were given 3 weeks to complete the survey.
Results
A total of 64 respondents from 58/120 (48%) sites completed the survey. 55/64 (86%) respondents were interested to participate in the SABR comparison, 44/64 (69%) in the 177Lutetium-PSMA-617 comparison, and 56/64 (87.5%) in the Abiraterone + Niraparib comparison. Access to treatment and novel imaging is summarised in table 1.
| Treatment | n/N | % [95% CI] |
| SABR (bone, spine, and nodes) | 45/64 | 70 [58-81] |
| 177Lutetium-PSMA-617 | 7/64 | 11 [5-21] |
| Novel imaging |
|
|
| PET/CT | 62/64 | 97 [89-99] |
| 18F-PSMA PET/CT | 36/62 | 58 [45-70] |
| 18F-Choline PET/CT | 25/62 | 40 [28-54] |
| 68Ga-PSMA PET/CT | 23/62 | 37 [25-50] |
| Whole-body MRI | 24/64 | 38 [26-50] |
Table 1. Access to treatment and novel imaging.
45/64 (70%) respondents requested PET/CT for disease uncertainty on conventional imaging, and 39/64 (61%) at disease relapse. 13/64 (20%) respondents requested Whole-body MRI in highly selected patients, and 7/64 (11%) for disease uncertainty on conventional imaging.
38/64 (59%) respondents requested scans at baseline and disease relapse in ‘low volume’ metastatic disease, and 29/64 (45%) requested scans at baseline, best response (corresponding to PSA nadir), and at disease relapse in ‘high volume’ metastatic disease. 54/64 (84%) respondents requested a CT and bone scan for best response assessment.
60/64 (94%) respondents used androgen receptor signalling inhibitors (ARSI), and 46/64 (72%) respondents used docetaxel in addition to androgen deprivation therapy (ADT). 29/64 (45%) respondents would consider docetaxel in addition to ADT and ARSI as part of ‘triple therapy’, if available. 46/64 (72%) respondents commenced ARSI with ADT.
Conclusion
The STAMPEDE2 trial will open with three investigative treatment arms in the HSPC setting. Currently, there is significant variation in practice across study sites in access and application of novel imaging, and therapeutic combinations at treatment initiation. Despite this, the majority of existing trial centres have expressed an interest to participate in STAMPEDE2.