Three junior residents were trained through the mentioned training mode for 2-week in advance by the same consultant before performing the biopsy independently. Biopsies were performed by one consultant and three junior residents independently every quarter from August 2018 to July 2019. In total, 343 patients were identified as suitable for inclusion in the study. 25 patients were excluded for general anesthesia. 31 patients were excluded for prior therapy for PCa.
1 Patient characteristics
The median age of the entire cohort was 67.25 years, and the median PSA was 11.89 ng/ml. Consultant and three residents performed 90, 85, 88 and 80 transperineal prostate biopsies respectively. Clinical characteristics of the patients in each group were shown in Table 1. There were no significant differences amongst groups in terms of age, PSA levels, the rate of patients underwent the mpMRI, and the comorbidity.
Table 1
|
Resident A
|
Resident B
|
Resident C
|
Consultant
|
P
|
Sample size
|
85
|
88
|
80
|
90
|
|
Body mass index
|
24.61 ± 3.09
|
23.98 ± 2.93
|
24.58 ± 2.74
|
24.33 ± 2.68
|
0.440
|
Age, year (range)
|
67.32 ± 9.18(39–89)
|
67.51 ± 7.44(45–84)
|
66.54 ± 7.84(47–84)
|
67.57 ± 9.87(41–87)
|
0.792
|
Median PSA, ng/ml (IQR)
|
10.97(7.37–24.21)
|
12.76(7.55–31.37)
|
11.92(7.86–32.71)
|
16.28(8.40–51.00)
|
0.311
|
Cases had mpMRI (n%)
|
33(38.8%)
|
32(36.4%)
|
26(32.5%)
|
46(51.1%)
|
0.071
|
Number of positive mpMRI (n%)
|
17(20.0%)
|
19(21.6%)
|
16(20.0%)
|
28(31.1%)
|
0.239
|
Hypertension (n%)
|
35(41.2%)
|
29(32.95%)
|
33(41.25%)
|
31(34.4%)
|
0.551
|
Coronary heart disease (n%)
|
2(2.4%)
|
4(4.55%)
|
1(1.25%)
|
2(2.2%)
|
0.629
|
Diabetes (n%)
|
5(5.9%)
|
7(7.95%)
|
9(11.25%)
|
7(7.8%)
|
0.653
|
IQR: Interquartile range; PSA: Prostate‑specific antigen; mpMRI: Multi-parametric magnetic resonance imaging. |
2 Detection rates of prostate cancer
As shown in Table 2, procedural time was significantly shorter for consultant versus residents (mean 16 min versus 19.7 to 20.1 min, P < 0.001). The proportions of PCa-positive biopsy were similar among the consultant and three residents. The detection rates of PCa were 61.1%, 54.1%, 58.0% and 52.5% for consultant and three residents, respectively (P = 0.733). Specifically, when stratified the approach of biopsy as SB and TB, no statistically significant differences for PCa detection rate for consultant and three residents. As for the number of TB cores, consultant had performed more TB cores compared with residents (175 cores versus 86 to 114 cores, P = 0.043), because more suspected lesions by mpMRI or ultrasound in the consultant group. However, there were no significant differences in the rates of PCa-positive TB cores between consultant and residents (43.4% versus 47.4–55.8%, P = 0.224). As for TB for lesions suspected by the urologists but with PI-RADS < 3, the positive rates were 1/6 (16.7%), 0/2 (0.0%), 1/4 (25.0%), 2/6 (33.3%), for A to C residents and consultant, respectively. The biopsy results of Gleason scores were summarized in Table 3. No obvious difference in Gleason scores was identified between the consultant and residents. Biopsies performed by consultant yielded the rates of Gleason ≥ 3 + 4 of 55.6%, and the rates of residents ranged from 46.3–53.4% (P = 0.568).
Table 2
The outcome of prostate biopsies between groups of residents and consultant
|
|
Resident A
|
Resident B
|
Resident C
|
Consultant
|
P
|
Time of PB(min)
|
|
20.1 ± 2.7
|
19.7 ± 3.1
|
20.0 ± 2.9
|
16.0 ± 2.6
|
< 0.0001
|
Overall positive rates of PB
|
|
54.1% (46/85)
|
58.0% (51/88)
|
53.8% (43/80)
|
61.1% (55/90)
|
0.733
|
|
Positive rates of SB
|
54.1% (46/85)
|
58.0% (51/88)
|
52.5% (42/80)
|
61.1% (55/90)
|
0.666
|
|
Positive rates of TB
|
52.9% (18/34)
|
64.3% (18/28)
|
57.1% (16/28)
|
51.0% (25/49)
|
0.707
|
Positive rates of TB cores
|
|
47.4% (54/114)
|
55.8% (48/86)
|
52.9% (46/87)
|
43.4% (76/175)
|
0.224
|
Positive rates of TB with different MRI approach
|
With mpMRI
|
52.2% (12/23)
|
66.7% (12/18)
|
64.7% (11/17)
|
55.6% (20/36)
|
0.736
|
|
With regular MRI
|
54.5% (6/11)
|
60.0% (6/10)
|
45.5% (5/11)
|
38.5% (5/13)
|
0.740
|
Positive rates of TB with PI-RADS stratification
|
|
64.7% (11/17)
|
75.0% (12/16)
|
76.9% (10/13)
|
75.0% (18/24)
|
0.886
|
|
3
|
66.7% (2/3)
|
40.0% (2/5)
|
60.0% (3/5)
|
33.3% (2/6)
|
0.805
|
|
4
|
55.6% (5/9)
|
83.3% (5/6)
|
83.3% (5/6)
|
88.9% (8/9)
|
0.442
|
|
5
|
80.0% (4/5)
|
100.0% (5/5)
|
100.0% (2/2)
|
88.9% (8/9)
|
1.000
|
Positive rates of TB with PI-RADS < 3
|
|
16.7% (1/6)
|
0.0% (0/2)
|
25.0% (1/4)
|
33.3% (2/6)
|
|
Median NRS (IQR)
|
|
2.00 (0.00–3.00)
|
2.00 (1.00–3.00)
|
1.50 (0.25-2.00)
|
2.00 (1.00–3.00)
|
0.085
|
PB: Prostate biopsy; SB: Systematic biopsy; TB: Targeted biopsy; PI-RADS: Prostate imaging |
reporting and data system; mpMRI: Multi-parametric magnetic resonance imaging; NRS: numeric rating scale; IQR: Interquartile range. |
Table 3
The Gleason Scores of biopsies with prostate cancer
Gleason Scores
|
6
|
3 + 4
|
4 + 3
|
8 or higher
|
Consultant (n%)
|
5(9.1%)
|
12(21.8%)
|
10(18.2%)
|
28(50.9%)
|
Resident A(n%)
|
5(10.9%)
|
12(26.1%)
|
8(17.4%)
|
21(45.7%)
|
Resident B(n%)
|
1(2.1%)
|
15(31.3%)
|
11(22.9%)
|
21(43.8%)
|
Resident C(n%)
|
4(9.8%)
|
10(24.4%)
|
5(12.2%)
|
22(53.7%)
|
Table 4 presented the PCa-detection rates of systemic and targeted biopsy further stratified by PSA value, and there was no statistical difference in the detection rate for PCa in different levels of PSA between consultant and residents. The only significant difference was captured for SB at PSA value between 20 to 100 ng/ml between resident A and resident C (94.4% versus 66.7%, P = 0.049). Further analysis revealed more patients underwent mpMRI at PSA value of 20 to 100 ng/ml in resident A group compared with resident B group (5 versus 2, P < 0.001), which suggested mpMRI might contributed to the detection of suspected lesions in SB. There was no significant difference in the rate of PCa-detection for TB of lesions with PI-RADS score ≥ 3 in mpMRI between consultant and residents (75.0% versus 64.7–76.9%, P = 0.886). The PCa-detection rates of TB with different PI-RADS scores of mpMRI were also examined, there was also no statistical difference among the consultant and residents (Table 4).
Table 4
PCa-detection rates of systemic and targeted biopsies stratified by PSA value
|
|
Resident A
|
Resident B
|
Resident C
|
Consultant
|
P
|
Positive cases of SB stratified by PSA value/total(n%)
|
0–10
|
10/40(25.0%)
|
12/35(34.3%)
|
10/32(31.3%)
|
10/36(27.8%)
|
0.832
|
|
10–20
|
10/18(55.6%)
|
15/24(62.5%)
|
11/20(55.0%)
|
13/19(68.4%)
|
0.807
|
|
20–100
|
17/18(94.4%)
|
15/20(75.0%)
|
14/21(66.7%)
|
19/22(86.4%)
|
0.135
|
|
> 100
|
9/9
|
9/9
|
7/7
|
13/13
|
|
Positive cases of TB stratified by PSA value/total(n%)
|
0–10
|
5/18(27.8%)
|
8/15(53.3%)
|
7/11(63.6%)
|
9/27(33.3%)
|
0.295
|
|
10–20
|
7/10(70.0%)
|
6/9(66.7%)
|
4/8(50.0%)
|
10/13(76.9%)
|
0.787
|
|
20–100
|
6/6(100.0%)
|
4/4(100.0%)
|
5/9(55.6%)
|
6/9(66.7%)
|
0.191
|
|
> 100
|
0
|
0
|
0
|
0
|
-
|
SB: systematic biopsy; PI-RADS: Prostate Imaging Reporting and Data System. |
3 Complications of prostate biopsy
As shown in Table 5, the complications were hematuria, fever, urinary retention and vaso-vagal reactions. The overall complication rate for consultant was 6.7%, and 5–8.2% for residents (P = 0.875). Notably, the most frequent collateral event was hematuria of varied degrees, which occurs for nearly all patients at the first urination after biopsy and could resolve spontaneously. Only those patients with obvious gross hematuria after biopsy and managed with placement of catheter at the discretion of urologists to prevent formation of blood clot in bladder were recorded. Two patients had fever over 38.5℃ within 24 hours after biopsy, and were treated with intravenous antibiotics. Three patients suffered urinary retention, and managed with indwelling catheter for 5 to 7 days and taken tamsulosin orally once a day. There were 13 patients experienced vaso-vagal reactions with symptoms of low blood pressure within 30 min after biopsy, and all of them recovered with continuous blood pressure monitoring and rest on bed. In terms of self-reported pain scale, there was no significant difference in NRS between the consultant and residents’ groups (P = 0.085).
Table 5
Complications after prostate biopsies
|
Resident A
|
Resident B
|
Resident C
|
Consultant
|
P
|
Overall complications(n%)
|
7(8.2%)
|
6(6.8%)
|
4(5.0%)
|
6(6.7%)
|
0.875
|
Hematuria(n%)┼
|
2(2.4%)
|
1(1.1%)
|
1(1.3%)
|
1(1.1%)
|
0.877
|
Fever(n%)
|
1(1.2%)
|
0(0.0%)
|
0(0.0%)
|
1(1.1%)
|
1.000*
|
Urinary retention(n%)
|
1(1.2%)
|
0(0.0%)
|
0(0.0%)
|
2(2.2%)
|
1.000*
|
Vaso-vagal reactions(n%)
|
3(3.5%)
|
5(5.7%)
|
3(3.8%)
|
2(2.2%)
|
0.687
|
*We just compared resident A and consultant in “fever” and “urinary retention” for no cases in these complications. |
┼Patients with obvious gross hematuria and managed with placement of catheter at the discretion of urologists to prevent formation of blood clot in bladder were recorded. |