Fluorine-18 prostate-specific membrane antigen (PSMA)-1007 PET/CT was superior to multiparametric MRI for main locoregional staging of prostate most cancers, in accordance with outcomes from a part II paired-cohort research.
Amongst 134 males present process radical prostatectomy, PSMA PET precisely recognized pathological tumor stage in 45% of sufferers in contrast with 28% of sufferers with MRI (P=0.003), reported Adam Kinnaird, MD, PhD, of the College of Alberta in Edmonton, Canada, and colleagues.
PSMA PET was additionally superior to MRI for the correct identification of the dominant nodule (94% vs 83%, P=0.01), laterality (64% vs 44%, P=0.001), and extracapsular extension (75% vs 63%, P=0.01), however not for seminal vesicle invasion (91% vs 85%, P=0.07), they wrote in JAMA Oncology.
Of observe, PSMA PET and MRI underestimated the tumor stage in 41% and 64% of sufferers, respectively.
“These findings help PSMA PET within the preoperative workflow of intermediate-risk and high-risk tumors,” Kinnaird and colleagues wrote.
In explaining the rationale behind the so-called Subsequent Technology trial, the authors famous that whereas PSMA PET has been proven to be superior to standard imaging (CT and bone scan) for nodal and metastatic staging, present pointers advocate using multiparametric MRI for locoregional staging of prostate most cancers earlier than radical prostatectomy.
“For a number of components, reminiscent of urinary accumulation of PSMA radioligands excreted by the kidneys, low-grade background prostatic exercise, and decrease decision of PET in comparison with MRI, the accuracy of prostate most cancers tumor staging has been restricted,” they added.
Fluorine-18 PSMA-1007 “is exclusive from different radioligands utilized in prostate most cancers in that it’s hepatically excreted,” Kinnaird advised MedPage At the moment. “This implies considerably much less background noise exercise within the urinary bladder, which due to this fact improves that skill to discern true exercise within the prostate gland, because the prostate is instantly adjoining to the bladder.”
On this potential research, the members underwent each fluorine-18 PSMA-1007 PET/CT and multiparametric MRI inside 2 weeks of each other and earlier than radical prostatectomy. The 134 sufferers within the ultimate evaluation had a imply age of 62 years; 95% had Gleason grade group 2 or 3 illness, and 49% had extraprostatic extension (T3a or T3b).
Whereas PSMA PET outperformed MRI in precisely figuring out tumor stage, Kinnaird and colleagues acknowledged that correct staging was noticed in lower than half of PSMA PET scans and barely greater than one-quarter of MRI scans.
“One clarification for this comparatively low diploma of general accuracy is that blinding the radiologists and nuclear medication physicians to biopsy outcomes and different imaging knowledge impaired the flexibility to make a prognosis that will be doable exterior of the trial in an ordinary scientific setting,” they wrote.
Kinnaird and colleagues urged that the research’s findings have vital implications for therapy selections, mentioning that PSMA PET’s superiority to MRI in detecting high-risk options reminiscent of extracapsular extension is “crucial,” since its presence alters surgical method.
“As an illustration, preoperative data of extracapsular extension might alter the choice to carry out nerve-sparing methods on the facet with anticipated tumor extension,” they wrote. “Equally, it might alter the extent of margin that’s sought throughout pericapsular dissection.”
As well as, the authors famous that the prevalence of PSMA PET in figuring out unilateral versus bilateral illness is vital for novel therapies — reminiscent of focal therapies — for prostate most cancers sufferers.
“The premise of focal remedy is to ablate solely the facet of the prostate the place the most cancers is current, thereby sparing the contralateral facet from dangerous therapy results,” they defined. “Due to this fact, the presence of bilateral illness is a contraindication to focal remedy.”
As for security, not one of the sufferers skilled an hostile occasion associated to both imaging modality.
The authors mentioned that future analysis ought to deal with the accuracy of mixing PET/CT and MRI, in addition to the cost-effectiveness of PET/CT for the first staging of prostate most cancers.
Disclosures
The trial was supported by the Canadian Urological Affiliation and collectively by the College Hospital Basis and Royal Alexandra Hospital Basis.
The research authors reported no conflicts of curiosity.
Major Supply
JAMA Oncology
Supply Reference: Mookerji N, et al “Fluorine-18 prostate-specific membrane antigen-1007 PET/CT vs multiparametric MRI for locoregional staging of prostate most cancers” JAMA Oncol 2024; DOI: 10.1001/jamaoncol.2024.3196.
