A total of 444 patients with gray-zone PSA were included in this study. Of these enrolled patients, 228 (51.4%) were patients in the TRB group, and 216 (48.6%) were patients in the TPB group (Table 1, Fig. 1). Of these 216 patients, 110 (50.9%) were patients who also underwent magnetic resonance imaging-transrectal ultrasound (MRI-TRUS) fusion-guided targeted biopsy following the systematic biopsy due to the suspected lesions (Fig. 2). After PSM, there were 113 patients in the TRB group and 113 in the TPB group (Table 1, Fig. 1).
Table 1
Baseline characteristics, biopsy results, and comparison between the TRB and TPB groups before and after PSM.
Parameters | Before PSM | After PSM |
Total (n = 444) # | TRB (n = 228) # | TPB (n = 216) # | P | | Total (n = 226) # | TRB (n = 113) # | TPB (n = 113) # | P |
Age (yrs) | 66 (61–72) | 66 (65–68) | 65 (65–67) | 0.545 | | 65 (61–72) | 66 (65–68) | 65 (64–67) | 0.275 |
tPSA (ng/ml) | 5.84 (7.26–8.67) | 7.32 (6.97–7.42) | 7.16 (6.91–7.35) | 0.674 | | 7.16 (5.87–8.56) | 6.97 (6.71–7.37) | 7.17 (6.92–7.52) | 0.389 |
fPSA (ng/ml) | 1.01 (0.72–1.38) | 1.05 (1.11–1.29) | 0.97 (0.98–1.11) | 0.075 | | 0.94 (0.67–1.30) | 0.89 (0.91–1.16) | 0.99 (0.97–1.13) | 0.112 |
(f/t)PSA | 0.15 (0.10–0.20) | 0.15 (0.16–0.18) | 0.14 (0.14–0.16) | 0.096 | | 0.13 (0.10–0.19) | 0.13 (0.13–0.17) | 0.14 (0.14–0.16) | 0.487 |
PV (ml) | 43.47 (30.33–65.15) | 47.14 (50.02–58.33) | 40.09 (43.77–50.70) | 0.020 | | 38.33 (27.14–55.18) | 36.59 (37.36–45.70) | 39.91 (42.06–50.23) | 0.080 |
PSAD (ng/ml2) | 0.16 (0.10–0.24) | 0.14 (0.16–0.19) | 0.17 (0.18–0.21) | 0.038 | | 0.18 (0.12–0.25) | 0.18 (0.19–0.24) | 0.17 (0.17–0.21) | 0.289 |
Needle cores | 13.00 (12.00–14.00) | 12 (12.50-12.81) | 14.00 (14.44–15.42) | < 0.001 | | 13.00 (12.00–14.00) | 13.00 (12.58–13.03) | 13.00 (12.67–13.14) | 0.587 |
CDR, No. (%) | | | | | | | | | |
Any PCa | 159 (35.8) | 51 (22.4) | 108 (50.0) | < 0.001 | | 88 (38.9) | 32 (28.3) | 56 (49.6) | 0.001 |
CSPCa* | 119 (74.8) | 34 (66.7) | 85 (78.8) | 0.103 | | 66 (75.0) | 22 (68.8) | 44 (78.6) | 0.306 |
TRB: transrectal prostate biopsy; TPB: transperineal prostate biopsy; PSM: propensity score matching; tPSA: total PSA; fPSA: free PSA; (f/t)PSA: free PSA/total PSA; PV: prostate volume; PSAD: PSA density; CDR: cancer detection rate; PCa: prostate cancers; CSPCa: clinically significant prostate cancers; #: Data are presented as median (interquartile range); *: International Society of Uropathology grade 2 or higher. |
Baseline characteristics and the stratified CDR before PSM.
The CDR of the TRB group was lower than that of the TPB group (22.4% vs. 50.0%, P < 0.001). The detection rate of CSPCa showed no significant difference between the TRB and the TPB groups (66.7% vs. 78.8%, P = 0.103) (Table 1). The median age, tPSA, fPSA, and (f/t)PSA were 66 years (interquartile range, IQR: 61–72), 5.84 ng/ml (IQR: 7.26–8.67), 1.01 ng/ml (IQR: 0.72–1.38), and 0.15 (IQR: 0.10–0.20), respectively. The TRB and the TPB groups did not differ in age (P = 0.545), tPSA (P = 0.674), fPSA (P = 0.075), and (f/t)PSA (P = 0.096) (Table 1). The median PV, PSAD, and needle cores were 43.47 ml (IQR: 30.33–65.15), 0.16 ng/ml2 (IQR: 0.10–0.24), and 13 (IQR: 12–14), respectively. The PV of the TRB group was more incremental than that of the TPB group (P = 0.020). In contrast, the PSAD and needle cores of the TRB group were lower than that of the TPB group (P = 0.020 and P < 0.001, respectively) (Table 1). In stratified analysis, the CDR of the TRB group was lower than that of the TPB group for patients aged 56–65 years (21.5% vs. 47.4%, P < 0.001) and aged 66–75 years (17.8% vs. 55.8%, P < 0.001). The CDR of the TRB group was lower than that of the TPB group when PV was 25-50ml (27.2% vs. 61.4%, P < 0.001). The CDR of the TRB group was lower than that of the TPB group no matter what the number of needle cores was (no less than 12 cores: 27.3% vs. 60.0%, P < 0.001; less than 12 cores: 17.1% vs. 45.7%, P < 0.001) (Table 2).
Table 2
Prostate cancer detection rate stratified by age, PV, and needle cores before and after PSM.
Parameters | Before PSM | | After PSM |
Total (n = 444) | TRB (n = 228) | TPB (n = 216) | P | | TRB (n = 113) | TPB (n = 113) | P |
Age (yrs), No. (%) | | | | | | | | |
≤55 | 8 (19.5) | 3 (12.5) | 5 (29.4) | 0.344 | | 2 (15.4) | 4 (36.4) | 0.357 |
56–65 | 62 (35.6) | 17 (21.5) | 45 (47.4) | < 0.001 | | 11 (27.5) | 21 (38.9) | 0.175 |
66–75 | 59 (35.3) | 16 (17.8) | 43 (55.8) | < 0.001 | | 9 (22.0) | 23 (59.0) | < 0.001 |
> 75 | 30 (48.4) | 15 (42.9) | 15 (55.6) | 0.321 | | 10 (52.6) | 8 (66.7) | 0.484 |
PV (ml), No. (%) | | | | | | | | |
<25 | 38 (66.7) | 16 (55.2) | 22 (78.6) | 0.061 | | 12 (50.0) | 12 (80.0) | 0.093 |
25 ≤ PV < 50 | 95 (46.1) | 25 (27.2) | 70 (61.4) | < 0.001 | | 17 (28.3) | 36 (63.2) | < 0.001 |
50 ≤ PV < 75 | 13 (12.2) | 5 (7.7) | 8 (19.5) | 0.071 | | 3 (13.6) | 5 (20.0) | 0.849 |
≥75 | 13 (17.3) | 5 (11.9) | 8 (24.2) | 0.161 | | 0 (0.0) | 3 (18.8) | 0.526 |
Needle cores, No. (%) | | | | | | | | |
≤12 | 71 (39.0) | 32 (27.3) | 39 (60.0) | < 0.001 | | 17 (31.5) | 31 (58.5) | 0.005 |
>12 | 88 (33.6) | 19 (17.1) | 69 (45.7) | < 0.001 | | 15 (25.4) | 25 (41.7) | 0.061 |
PV: prostate volume; PSM: propensity score matching; TRB: transrectal prostate biopsy; TPB: transperineal prostate biopsy; CDR: cancer detection rate. |
Baseline characteristics and the stratified CDR after PSM.
The CDR of the TRB group was lower than that of the TPB group (28.3% vs. 49.6%, P = 0.001). The detection rate of CSPCa still showed no significant difference between the TRB and the TPB groups (68.8% vs. 78.6%, P = 0.306) (Table 1). The median age, tPSA, fPSA, (f/t)PSA, PV, PSAD, and needle cores were 65 years (IQR: 61–72), 7.16 ng/ml (IQR: 5.87–8.56), 0.94 ng/ml (IQR: 0.67–1.30), 0.13 (IQR: 0.10–0.30), 38.33 ml (IQR: 27.14–55.18), 0.18 ng/ml2 (IQR: 0.19–0.24), and 13 (IQR: 12–14), respectively. The TRB and the TPB groups did not differ in these parameters (P = 0.275, 0.389, 0.112, 0.487, 0.080, 0.289, 0.587, respectively) (Table 1). In stratified analysis, the CDR of the TRB group was lower than that of the TPB group when the age of patients was 65–75 years (22.0% vs. 59.0%, P < 0.001) when PV was 25-50ml (28.3% vs. 63.2%, P < 0.001), and when the number of needles was no more than 12 cores (31.4% vs. 58.5%, P = 0.005) (Table 2).
The effect of different biopsy strategies on CDR.
A total of 110 patients with gray-zone PSA received MRI-TRUS fusion-guided targeted transperineal biopsy following the systematic biopsy due to the suspected lesions. The CDR of the systematic, targeted, and combined biopsy groups were 49.1%, 45.4%, and 50.9%, respectively. The detection rate of CSPCa of the systematic, targeted, and combined biopsy groups were 85.2%, 86.0%, and 83.9%, respectively. The CDR (P = 0.712) and the detection rate of CSPCa (P = 0.993) showed no significant difference among the three groups (Fig. 2).