Balancing the benefits and harms of MRI-directed biopsy pathways.

KEY POINTS: • Before a prostate biopsy, the likely benefits and the harms emanating from true and false test MRI results need to be balanced. Prioritizing patients' preferences and their tolerance to potential harms are essential to assess.• The decision curve analysis method is an analytical framework where the net clinical benefit is plotted against a range of risk thresholds of having important cancers, helping patients and their physicians to decide between cancer averse (important cancers being detected) and biopsy averse (biopsies avoided) strategies.• The decision curve analysis method showed that the incorporation of clinical risk factors with MRI findings optimizes biopsy outcomes over a range of clinically relevant risk thresholds, compared to other biopsy strategies.

Contrast Medium or No Contrast Medium for Prostate Cancer Diagnosis. That Is the Question.

The benefits and drawbacks of the dynamic contrast-enhanced MRI sequence for prostate cancer diagnosis are increasingly being recognized, with many centers adopting the biparametric (bp) MRI approach as the default initial approach. The abandonment of the routine use of contrast medium requires an assessment of the loss of diagnostic power against the gains in operational logistics, costs, time, capacity, and side effects. It is the balance of these factors weighted against the clinical priorities of patients that determines which patient groups can safely avoid dynamic contrast enhancement. Although systematic reviews and individual studies are broadly supportive of the bpMRI approach, the pathway impacts for men with suspected cancer using the bpMRI approach are still not well documented for clinical practice. Robust prospectively acquired data for bpMRI regarding biopsy avoidance, detection of clinically significant and insignificant cancers, and for increasing the precision of tumor grade and volume are needed. There is a requirement for prospective, randomized, or blinded head-to-head, multicenter studies, addressing the noninferiority of biopsy yields prompted by bpMRI and multiparametric MRI approaches. These studies should more precisely define patient groups where the benefits and harms of contrast enhancement are aligned to their clinical priorities. Only then can we be confident in recommending bpMRI as an initial diagnostic approach for prostate cancer diagnosis. Level of Evidence 1 Technical Efficacy Stage 5.

Comparison of biopsy strategies for prostate biopsy according to lesion size and PSA density in MRI-directed biopsy pathway.

PURPOSE: To investigate whether the detection of clinically significant prostate cancer (csPCa) and the added value of focal saturation biopsy and systematic biopsy (SBx) differ according to index lesion size, and to compare the current guidelines for csPCa detection. METHODS: This retrospective study included consecutive men who underwent MRI and subsequent SBx and MRI-targeted biopsy (TBx) for a suspicious lesion between April 2019 and February 2020. Lesion visibility on transrectal ultrasound (US) and added value of focal saturation biopsy and SBx were compared according to index lesion size using chi-square and McNemar tests. csPCa detection rates and the proportion of biopsy-indicated men were compared among four biopsy strategies based on current guidelines. RESULTS: Of 313 men evaluated (median age, 65; interquartile range 60‒71), csPCa was detected in 110 (35%). In lesions < 10 mm, greater US invisibility (42.7% of lesions < 10 mm versus 20.0% of lesions ≥ 10 mm; p < 0.001) and higher added value of focal saturation biopsy and SBx (11.1% and 17.1% in lesions < 10 mm versus 4.2% and 6.3% in lesions ≥ 10 mm) were observed, compared with lesions ≥ 10 mm. Consideration of prostate-specific antigen (PSA) density > 0.15 ng/mL/mL as a cutoff in unsuspicious MRI led to a 14% reduction (44/313) in men who needed biopsy. CONCLUSION: Determination of the biopsy strategy in terms of the need for focal saturation biopsy or SBx should be made considering lesion size. The use of PSA density in non-suspicious MRI can lead to a reduction in biopsy-indicated men.