Screening PROMPTS.

Top Line: Does screening MRI reduce the risk of symptomatic spinal cord compression among men with metastatic, castration resistant prostate cancer (mCRPC)?

The Study: The spine is a common site of mCRPC bone metastases, and some spine mets can lead to spinal cord compression (SCC). We know that early treatment of SCC is more likely to preserve neurological function. PROMPTS was a large, multicenter randomized trial in the UK designed to determine whether an MRI could identify those at risk of developing clinically significant SCC. Men with mCRPC and asymptomatic spine metastases (n=420) were randomized to have a screening MRI of the spine, which included imaging of the entire spine. Radiologists used a 7-point scale (based on Bilsky scale) to determine the presence of radiographic SCC (basically any extension to the epidural space). Radiographic SCC was found in nearly a third of men (31%), and most of those (70%) had relatively limited epidural extension (grade 1a or 1b with no abutment of the cord). They were offered preemptive treatment with radiation or surgical decompression, and 82% of them received radiation (most commonly 20Gy in 5 fractions). Even though nearly a third of men had radiographic SCC, a smaller proportion actually developed clinically symptomatic SCC in follow-up. In the control group, the rate of symptomatic SCC at 12 and 24 months was 6.7% and 12.6%. Screening MRI and pre-emptive treatment did not significantly reduce the rate of symptomatic SCC at 12 (4.3%) or 24 months (9.2%).

TBL: Screening MRI of the spine for men with asymptomatic spine metastases from mCRPC does not significantly reduce the rate of clinically symptomatic spinal cord compression at 12 or 24 months. | Dearnaley, Lancet Oncol 2022