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stringent criteria. Particularly, we included only studies
that: (1) had biopsy protocols with at least 10 cores, since it
is no longer recommended to obtain less than 10 cores per
biopsy; (2) used DWI, which is the most informative
technique, at least for cancers in the peripheral zone
[60] ;and (3) reported mpMRI findings using a five-level score, so
that negative findings could be better defined. We accepted
studies using a subjective (Likert) scale because experi-
enced readers obtained equivalent
[45,61,62]or better
[63]results with the Likert score than with the PI-RADS v1 score.
Table 4 – Prebiopsy multiparametric MRI results in the series selected for the meta-analysis
Study
Prevalence
a (%)
Neg MRI (%)
NPV (%)
PPV (%)
Spe (%)
Se (%)
All PCa
Score 3/5 Grenabo Bergdahl (2016)
[22]31.3
66.9
83.7
47.5
63.2
73.1
Numao (2013)
[38]45
29.4
70.6
64.3
71.0
63.9
Hauth (2015)
[25]45.7
14.3
85.7
48.3
11.8
97.7
Vinet (2013)
[57]49.3
24.6
64.7
53.8
31.4
82.4
Radtke (2015)
[46]51
27
73
73.2
71.5
74.7
Thompson (2014)
[56]61.3
31.4
68.6
76.8
60.3
82.6
Pokorny (2014)
[43]63.7
30.9
69.1
82.4
69.1
82.4
Score 4/5 Pepe (2015)
[41]37
31
74.2
42
36.5
78.4%
Vinet (2013)
[57]49.3
47.8
66.7
63.9
62.9
67.6%
Radtke (2015)
[46]51
73.5
63.9
92.3
95.8
48%
Gleason 7 PCa Score 3/5 Radtke (2015)
[46]29.3
27
87.9
45.1
59.6
80.2%
PCa = prostate cancer; MRI = magnetic resonance imaging; Neg MRI = proportion of negative magnetic resonance imaging; NPV = negative predictive value;
PPV = positive predictive value; Se = sensitivity; Spe = specificity.
a
Prevalence of overall prostate cancers (10 first lines) or Gleason 7 cancers (last line).
[(Fig._4)TD$FIG]
Fig. 4 – Forest plot showing the (A) NPV and (B) PPV of prebiopsy multiparametric MRI for overall prostate cancer in the seven studies selected for
meta-analysis that used a cut-off score of
I
3/5 for defining positive MRI. Studies have been ranked according to cancer prevalence (left column).
Intervals in the right column are 95% CIs of the (A) NPV or (B) PPV. As NPV and PPV vary with cancer prevalence, combined estimates of NPV and PPV
have not been provided. (C) Conditional probability plot showing the estimation of the combined NPV and PPV in the seven studies, as a function of
the prevalence of overall prostate cancer. The
x
axis (prior probability) indicates the overall prostate cancer prevalence. The
y
axis (posterior
probability) indicates either PPV (dashed line, upper quadrant) or 1 – NPV (dotted line, lower quadrant). CI = confidence interval; MRI = magnetic
resonance imaging; NPV = negative predictive value; PPV = positive predictive value.
E U R O P E A N U R O L O G Y 7 2 ( 2 0 1 7 ) 2 5 0 – 2 6 6
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