Population.
A total of 201 biopsy-naïve patients were found to be eligible for the study, with 95 (47.26%) undergoing TB and 106 (52.74%) undergoing TSB. No significant differences were observed between the two groups in terms of age at the time of surgery, Body Mass Index (BMI), pre-surgery tPSA levels, age-adjusted Charlson Comorbidity Index (aaCCI), DRE findings, and smoking habits (Table I: Pre-Surgery Demographic and Clinical Characteristics of the Patients).
Spatial correlation with whole-mount analysis of mpMRI and Prostate Biopsy.
As expected, the best location agreement was found between mpMRI lesions and TB, with a Pearson’s correlation coefficient (R) of 0.778 (p < 0.001). In contrast, a moderate correlation was observed when comparing TB with WMA and mpMRI with WMA in the same group, with Pearson’s correlation coefficients of 0.515 (p = 0.01) and 0.446 (p = 0.01), respectively.
In the TSB group, a lower correlation was found when comparing mpMRI suspicious lesions and TSB positive cores (R = 0.425, p = 0.01), suggesting that this biopsy approach may detect some disease foci that remain undetected by mpMRI. A moderate correlation (R = 0.401, p = 0.02) was observed between mpMRI and WMA, while a fairly strong correlation was found between TSB and WMA, with an R of 0.704 (p < 0.001).
Notably, in 9 (8.5%) patients within the TSB group, the systematic biopsy was essential for diagnosing csPCA, as TB had not detected the presence of the disease.
Similar results were observed when stratifying by PI-RADS score, particularly for PI-RADS scores of 4 and 5. The TB showed the strongest correlation with mpMRI for PI-RADS 5 lesions (R = 0.815, p < 0.001). However, for PI-RADS 3 ROIs, TB did not achieve a statistically significant correlation with WMA (R = 0.267, p = 0.218). Results are summarized in Table II.
A moderate correlation was found between the mpMRI report, PB, and WMA analysis, with TB showing a stronger correlation with mpMRI than TSB. Conversely, TSB performed better when compared to WMA. This can be explained by the fact that systematic samples may detect some prostate cancer foci that are not identified by mpMRI.
When stratified by PI-RADS score, the results remained consistent, except for the comparison between TB and WMA for PI-RADS 3 lesions, where no statistically significant correlation was observed.
Comparison between mpMRI, PB and WMA concerning csPCa areas.
A paired data Student's t-test was performed to compare the average number of positive areas detected by mpMRI, PB, and WMA in both groups. As shown in Table III, mpMRI detected fewer lesions than those later identified by PB and WMA. This was consistent for both TB and TSB groups.
In the TB group, mpMRI detected an average of 2.03 ± 1.22 lesions, PB detected 2.50 ± 1.34 positive areas, and WMA identified 4.00 ± 1.53 positive areas (p < 0.001 for all comparisons). Similarly, in the TSB group, mpMRI detected 1.90 ± 1.29 lesions, PB identified 3.35 ± 1.60 positive areas, and WMA detected 4.27 ± 1.62 positive areas (p < 0.001 for all comparisons). These findings remained significant even when stratified by PI-RADS score (Table III).
The average percentage of mpMRI-detected lesions compared to WMA was similar between the two groups: mpMRI identified 50.8% of the lesions later confirmed by WMA in the TB group and 44.8% in the TSB group (p = 0.139). A significant difference was found when comparing the two biopsy approaches: TB identified 62.5% of the csPCa lesions, while TSB identified 79% of the lesions (p < 0.001).
Our results suggest that mpMRI can identify less than 50% of csPCa lesions, consistent across both groups. However, there is a significant difference between the two biopsy techniques when compared to WMA. This implies that the addition of systematic sampling may lead to better local staging and spatial assessment of the disease.
Correlation between PCa Gleason Score and mpMRI PI-RADS score.
Among patients who underwent TB, a weak but significant correlation was found between mpMRI lesion PI-RADS scores and Gleason scores from both PB and WMA (R = 0.341, p = 0.01 and R = 0.323, p = 0.01, respectively). In contrast, a moderate correlation was observed between PB and WMA GS within the same group, with a Pearson’s correlation coefficient of 0.511 (p < 0.001).
Similar outcomes were observed in the TSB group. There was a weak correlation between mpMRI PI-RADS scores and WMA GS (R = 0.233, p = 0.025), and a moderate correlation between PB and WMA GS (R = 0.526, p < 0.001). However, in the TSB group, the correlation between mpMRI PI-RADS scores and PB GS did not reach statistical significance (R = 0.125, p = 0.235) (Table IV).
Similar rates of upgrading and downgrading were found (p = 0.78 and p = 0.43, respectively). In particular, in TB group 20 (21.1%) patients had a GS upgrade at WMA. Similarly, in TSB group 24 (22.6%) patients had a higher reported GS at WMA than at PB. Downgrading was less frequent, occurring in 13.6% of patients in the TB group and 14.3% of patients in the TSB group.
Our results suggest that while mpMRI can provide some indication of tumor aggressiveness, the correlation between PI-RADS scores and Gleason Scores (GS) from both PB and WMA was found to be weak.