The aim of this study was to generate an objective method to describe MRI data to assess response in the vertebrae of patients with metastatic hormone sensitive prostate cancer (mHSPC), treated with external beam radiation therapy and systemic therapy with Radium-223 and to correlate changes with clinical outcomes.
Three sets of whole-body MRI (WBMRI) images were utilized from 25 patients from the neo-adjuvant Androgen Deprivation Therapy pelvic Radiotherapy and RADium-223 (ADRRAD) clinical trial: MRI1 (up to 28 days before Radium-223), MRI2 and MRI3 (2 and 6 months post completion of Radium-223). Radiological response was assessed based on post baseline MRI images. Vertebrae were semi-automatically contoured in the sagittal T1-weighted(T1w) acquisitions, MRI intensity was measured, and spinal cord was used to normalise the measurements. The relationship between MRI intensity vs time to biochemical progression and radiology response was investigated. Survival curves were generated and splitting measures for survival and biochemical progression investigated.
Using a splitting measure of 1.8, MRI1 was found to be a reliable quantitative indicator correlating with overall survival (p = 0.023) and biochemical progression (p = 0.014). MRI(3-1) and MRI(3-2) were found to be significant indicators for patients characterised by progressive/non-progressive disease (p = 0.021, p = 0.004) and biochemical progression within/after 12 months (p = 0.007, p = 0.001).
We have identified a potentially useful objective measure of response on WBMRI of vertebrae containing bone metastases in mHSPC which correlates with survival/progression (prognostic) and radiology response (predictive).
Measurements of T1w WBMRI normalised intensity may allow identifying potentially useful response biomarkers correlating with survival, radiological response and biochemical progression.
The British journal of radiology. 2024 Jan 24 [Epub ahead of print]
Valentina Giacometti, Arthur C Grey, Aaron J McCann, Kevin M Prise, Alan R Hounsell, Conor K McGarry, Joe M O'Sullivan
Patrick G. Johnston Centre for Cancer Research, Queen's University Belfast, UK., Department of Imaging Services, Belfast Health & Social Care Trust, UK., Radiological Imaging & Protection Service, Regional Medical Physics Service, Belfast Health & Social Care Trust, UK.