Accuracy of multiparametric magnetic resonance imaging in confirming eligibility for active surveillance for men with prostate cancer

Abstract

BACKGROUND: Active surveillance (AS) is an attempt to avoid overtreatment of clinically insignificant prostate cancer (PCa); however, patient selection remains controversial. Multiparametric prostate magnetic resonance imaging (MP-MRI) may help better select AS candidates. METHODS: We reviewed a cohort of men who underwent MP-MRI with MRI=Ultrasound fusion-guided prostate biopsy and selected potential AS patients at entry using Johns Hopkins criteria. MP-MRI findings were assessed, including number of lesions, dominant lesion diameter, total lesion volume, prostate volume, and lesion density (calculated as total lesion volume=prostate volume). Lesions were assigned a suspicion score for cancer by MRI. AS criteria were reapplied based on the confirmatory biopsy, and accuracy of MP-MRI in predicting AS candidacy was assessed. Logistic regression modeling and chi-square statistics were used to assess associations between MP-MRI interpretation and biopsy results. RESULTS: Eighty-five patients qualified for AS with a mean age of 60.2 years and mean prostate-specific antigen level of 4.8 ng=mL. Of these, 25 patients (29%) were reclassified as not meeting AS criteria based on confirmatory biopsy. Number of lesions, lesion density, and highest MRI lesion suspicion were significantly associated with confirmatory biopsy AS reclassification. These MRI-based factors were combined to create a nomogram that generates a probability for confirmed AS candidacy. CONCLUSION: As clinicians counsel patients with PCa, MP-MRI may contribute to the decision-making process when considering AS. Three MRI-based factors (number of lesions, lesion suspicion, and lesion density) were associated with confirmatory biopsy outcome and reclassification. A nomogram using these factors has promising predictive accuracy for which future validation is necessary.

Multiparametric Magnetic Resonance Imaging and Image-Guided Biopsy to Detect Seminal Vesicle Invasion by Prostate Cancer

“…Given the large number of recent studies that have demonstrated the utility of targeted biopsy for intraprostatic lesions, this technique is likely to become increasingly widespread. 8,10,[22][23][24] The present study supports targeted biopsy of the SVs when indicated by imaging. It should be noted that the targeted biopsies performed in this study were based on diagnostic MRIs obtained on a 3-Tesla magnet with an endorectal coil and MP-MRI sequences, including T2-weighted, DCE, DWI, and MRS.…”

Novel Tools to Improve Patient Selection and Monitoring on Active Surveillance for Low-risk Prostate Cancer: A Systematic Review

“…The literature search identified 30 original articles that were included for review: 14 on magnetic resonance imaging (MRI) [8][9][10][11][12][13][14][15][16][17][18][19][20][21], 5 on serum markers [22][23][24][25][26], 5 on urinary markers [27][28][29][30][31], 4 on histopathology markers [32][33][34][35], and 2 on germline genetic markers [36,37]. Figure 1 presents the search strategy and study selection flowchart.…”

“…Stamatakis et al reported the findings of 3-T MP-MRI in AS patients according to the Johns Hopkins criteria (n = 85) [15]. The number of lesions on MRI, rate of suspicion of lesions (number of positive sequences), and lesion density (lesion volume divided by prostate volume) were associated with findings at confirmatory biopsy, including MRItransrectal ultrasound (TRUS) fusion-guided biopsies.…”

Active Surveillance of Prostate Cancer: Use, Outcomes, Imaging, and Diagnostic Tools

“…61 The National Cancer Institute nomogram, which uses only mpMRI criteria, generated an AUC of 0.71 for predicting candidates for AS in a cohort of 85 patients, 60 of whom had very low-risk disease (≤cT1c, PSA density <0.15, biopsy Gleason score ≤6, ≤ 2 positive biopsy cores, and ≤50% cancer involvement in any biopsy core). 62 This nomogram was developed with biopsy pathology as an endpoint, which is a method that has not been validated. Thus, while mpMRI appears to provide some incremental value in selecting candidates for AS, it is far from perfect and remains limited by an inability to consistently detect clinically significant lesions, with reported false-negative rates of up to 16%.…”

“…Performing mpMRI prior to entering AS can reduce the number of inappropriate AS candidates by 29% (Figures 1 and 2). 62 Once a patient has initiated AS, mpMRI can be useful in demonstrating lesion stability (Figure 3) but currently lacks the sensitivity to reliably detect higher-risk lesions during follow-up. As such, continued serial biopsies are recommended until mature data indicate that a stable mpMRI may in fact preclude subsequent biopsy.…”