Emerging Research in Prostate Cancer Imaging — October 2024
Diagnostic Imaging®
The latest news and commentary for radiologists and medical imaging professionals.
Touching on a variety of topics in prostate cancer imaging, ranging from new research comparing PSMA PET/CT and PSA response after mCRPC treatment to AI advances for PCa detection on mpMRI, here are the top five most well-viewed prostate imaging content from Diagnostic Imaging for October 2024.
By Diagnostic Imaging Staff
New Study Assesses Long-Term Outcomes of PSMA PET Use in PCa Recurrence Cases
A recent study in JAMA Network Open found that prostate-specific membrane antigen positron emission tomography (PSMA PET) significantly improves metastasis detection, quality-adjusted life years (QALYs), and reduces mortality compared to conventional imaging in patients with prostate cancer (PCa) recurrence. Researchers simulated outcomes for 1,000 patients with biochemical recurrence (BCR), comparing immediate PSMA PET use, combined computed tomography and bone scan (CTBS) with PSMA PET for inconclusive CTBS, and CTBS alone. Immediate PSMA PET detected metastasis in 611 patients, compared to 297 with CTBS alone. PSMA PET yielded 8,741 QALYs versus 7,917 with CTBS alone. Additionally, PSMA PET reduced PCa-specific deaths by 75 per 1,000 patients compared to CTBS alone. Benefits were more pronounced for patients with PSA levels >5 ng/mL
Emerging AI Platform Shows Promise for Prostate Cancer Detection on mpMRI
In a recent study published in the European Journal of Radiology, researchers evaluated the AI-based mdprostate software for prostate cancer detection using multiparametric MRI (mpMRI) in 123 men. With 100% sensitivity and negative predictive value at a PI-RADS > 2 cutoff for clinically significant prostate cancer (csPCa), mdprostate showed potential for reducing unnecessary biopsies and associated healthcare costs. However, specificity at this threshold was low (7.5%). At higher PI-RADS cutoffs, sensitivity and specificity improved, with 85.5% sensitivity and 60.3% specificity at PI-RADS > 3.
Can 18F-Flotufolastat Bolster Detection of PCa Recurrence in Patients with Low PSA Levels After Radical Prostatectomy?
The PET agent 18F-flotufolastat shows a promising detection rate for recurrent prostate cancer in patients with PSA levels below 1 ng/mL, as highlighted in findings from the SPOTLIGHT trial presented at ASTRO. In a recent interview, Bridget Koontz, M.D., noted that delayed renal clearance of 18F-flotufolastat reduces urinary bladder uptake, which can often obscure imaging, providing clearer results in low PSA patients likely to have prostate bed recurrence rather than metastasis. Detection rates were impressive: 74% in patients with PSA between 0.5–1 ng/mL, 67% in those with PSA between 0.3–0.5 ng/mL, and 68% for PSA levels between 0.2–0.3 ng/mL.
Study Shows Discordance Between PSMA PET/CT and PSA Response in 47 Percent of Patients Treated for mCRPC
A recent retrospective study, published in the European Journal of Radiology, compared prostate-specific membrane antigen (PSMA) PET/CT using (18F)PSMA-1007 with prostate-specific antigen (PSA) response in evaluating treatment efficacy for metastatic castration-resistant prostate cancer (mCRPC). In a cohort of 60 patients treated with either androgen receptor-targeted agents (ARTAs) or chemotherapy, PSMA PET/CT and PSA response provided discordant results in 47% of cases. In 89% of these, PSMA PET/CT indicated worse treatment response than PSA levels suggested. Notably, 31% of patients with a PSA decrease >50% still exhibited disease progression on PSMA PET/CT.
AI Segmentation, Intraprostatic Tumor Volume and Metastases: What a New mpMRI Study Reveals
A recent study published in Radiology highlights the potential of AI-based tumor segmentation using multiparametric MRI (mpMRI) for predicting metastasis in patients with localized prostate cancer (PCa). Researchers developed an AI algorithm for segmenting Prostate Imaging Reporting and Data System (PI-RADS) 3-5 lesions to calculate total intraprostatic tumor volume (VAI) and compared its predictive performance to the National Comprehensive Cancer Network (NCCN) risk classification in 732 patients undergoing radical prostatectomy (RP) or radiotherapy (RT). Results showed VAI had higher predictive accuracy for metastasis than NCCN classification, achieving an AUC of 84% in RT patients and 89% in RP patients.