Radical prostatectomy after cancer confirmation via two advanced imaging techniques without biopsy is feasible, according to a retrospective study of 25 patients who refused biopsies.
âThe results of our case series may trigger the discussion on [radical prostatectomy] without prior biopsy as a possible option in well-selected patients, âwrite Valentin H. Meissner, MD, and colleagues at the Technical University of Munich, Germany.
Current guidelines call for a prostate biopsy if an elevated prostate specific antigen or abnormal digital rectal examination suggests cancer. But biopsies can lead to complications, such as sepsis, urinary retention, and hematuria requiring catheterization.
However, the use of multiparametric magnetic resonance imaging (mpMRI) alone may not be sufficient to diagnose patients. Studies show that pMRI misses about 10% of significant prostate cancers and has low positive predictive value.
In the current case series, the authors reported their experience combining two advanced imaging modalities – pMRI and prostate specific membrane antigen (PET) positron emission tomography (PSMA) – as the primary diagnostic tool. to detect and treat prostate cancer in patients who have refused biopsy.
“Improving the accuracy of prostate specific membrane antigen (PSMA) positron emission tomography (PET) scanning raises the question of whether this imaging modality can complement mpMRI to safely avoid biopsy. before radical prostatectomy, “Meissner and colleagues write in their review, published Dec. 6. in European urology.
Recent studies have already suggested that the two combined imaging techniques are more precise than mp MRI alone, suggesting that “men with suspicious results from PSMA-PET and mpMRI could potentially avoid the biopsy and undergo definitive treatment” , write the authors.
In the current case series, Meissner and colleagues followed 25 patients who elected to undergo radical prostatectomy based on the results of mpMRI and PSMA-PET imaging without biopsy, despite the surgeon’s recommendation to undergo a biopsy.
The men had a median PSA level at diagnosis of 7.3 ng / mL and a median age of 71 years. ) score of at least 4 and a PET score of at least 4 (with a median standardized absorption value [SUVmax] of 9.5).
After undergoing radical prostatectomy, all patients had significant prostate cancer greater than grade 1 on histopathological assessment, as defined using the International Society of Urological Pathology (ISUP). Specifically, eight of the 25 patients were ISUP grade 2, 15 were ISUP grade 3, and two were ISUP grade 5.
MpMRI and PSMA-PET had a sensitivity of 100% and a positive predictive value of 100%. PSMA-PET and mpMRI successfully identified four cases of seminal vesicle invasion, 4 of 6 cases of extracapsular extension, and 13 cases of locally contained disease. In four patients, researchers found lymph node invasion in the final pathology, and PSMA-PET correctly identified one of them preoperatively.
However, two patients whose cancer was suspected of extracapsular extension on mpMRI and PSMA-PET showed a disease locally confined to histopathology. Conversely, two patients with cancer suspected of a disease locally confined in these imaging studies showed extracapsular extension in histopathology.
The authors recognize “a risk of false positive results leading to unnecessary surgery”. But they argue that the risk could be minimized by experienced nuclear physicians using a validated SUVmax threshold.
âThe results of the current retrospective case series were promising and showed that in patients with a strong suspicion of [prostate cancer] in mpMRI and PSMA-PET, avoidance of prostate biopsy before [radical prostatectomy] could represent a valid option in well advised and selected patients â, write the authors.
However, they caution, “our case series is limited by retrospective design and small sample size. We want to make it clear that this practice should not be viewed as standard procedure at this time.”
As such, the authors requested a clinical trial with a larger patient population to validate the results.
Although Scott Eggener, MD, a urologist oncologist at the University of Chicago, Illinois, found the study stimulating and believes that a radical prostatectomy without a biopsy is worth considering, this option remains an academic question only at this stage. .
In Eggener’s experience, the only men who had radical prostatectomy without a biopsy sought prophylaxis because so many men in their families had died of prostate cancer.
But if enough men skip the biopsies, some will inevitably have surgery they didn’t need, he said. Medscape Medical News.
âIt absolutely can fall in the trash of the history of prostate cancer. But if more studies are done thoughtfully, the combination of PSA, MRI and PET may someday help. ‘avoid biopsies for some men,’ said Eggener, who was not involved in the research.
A co-author, Matthias Eiber, reported consulting activities for Blue Earth Diagnostics, Progenics Pharmaceuticals, Keosys, Novartis, Telix Pharma, Amgen and Point Biopharma, as well as a patent application for rhPSMA. The other authors had nothing to disclose. Eggener did not report any relevant financial interest.
Eur Urol. Published online December 6, 2021. Summary
Laird Harrison writes on science, health and culture. His work has been published in magazines, newspapers, public radio and on websites. He is working on a novel on alternative realities in physics. Harrison teaches writing at Writers Grotto. Visit him on lairdharrison.com or follow him on Twitter: @LairdH.
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