1. Urologist’s Impact on Extended Needle Core Prostate Biopsy Histopathologic Variables within a Single Institution
Kashika G. Goyal B.S.1, Joshua J. Ebel M.D.2, Soud A. Sediqe B.S.1, David S. Sharp M.D.2, Debra L. Zynger M.D.1
Department of Pathology1, Department of Urology2
The Ohio State University Medical Center
Background:
Prostate needle core biopsy is a critical procedure to diagnose and manage prostatic adenocarcinoma.
There is a lack of understanding of how the submitting urologist impacts histopathologic metrics within prostate needle core biopsies.
Our study aimed to elucidate the relationship between submitting urologist, number of containers in which cores are submitted, longest core length, total core length, and individual core length threshold values on cancer detection rate per case within extended core biopsies.
Results:
Cohort characteristics are shown in Figure 1 and Table 1.
Total core length (mean cm, p<0.001) and longest core length (mean cm, p<0.001) significantly varied by submitting urologist but these variables did not impact cancer detection rate per case (p=0.88, p=0.41, respectively) (Table 2, Table 4, Figure 2 A and B).
For the single urologist with a change in his submission protocol during the study period, the cancer detection rate was no different comparing containers versus 6-9 containers (p=0.64) (Table 3, Figure 2 C and D).
Number of individual cores that met threshold values of 0.5 cm, 1.0 cm, and 1.5 cm, and container number significantly varied by submitting urologist (p<0.001) but did not impact cancer detection rate per case (p=0.60, 0.84, 0.50, 0.12 respectively) (Table 4).
Core length per container significantly impacted the cancer detection per container (p<0.001) (Table 4 and Figure 2 E).
Figure 1: Percentage of prostate needle core biopsy cases by diagnosis
Table 4: Significance of variables included in study
Variable
Urologist’s Impact
(p value)
Impact on Cancer Detection
Total Core Length
<0.001
0.88
Longest Core Length
0.41
Number of Cores > 0.5 cm in length
0.60
Number of Cores > 1.0 cm in length
0.84
Number of Cores > 1.5 cm in length
0.50
Container Number
0.12
Core Length Per Container
Figure 2: Representative cases demonstrating variation in core length and container number
Table 1: Number and diagnosis of prostate biopsies per urologist
Diagnosis
Carcinoma
Negative
HGPIN
ASAP
HGPIN/ASAP
Urologist 1 (n=432)
54.9%
37.5%
2.8%
3.9%
0.9%
Urologist 2 (n=347)
50.7%
37.2%
4.9%
4.3%
2.9%
Urologist 3 (n=302)
44.7%
45.0%
6.0%
3.0%
1.3%
Urologist 4 (n=261)
55.2%
34.5%
7.3%
1.5%
Urologist 5 (n=134)
59.0%
32.8%
0.7%
Urologist 6-15 (n=192)
43.2%
43.8%
3.6%
2.1%
Total (n=1668)
51.2%
38.7%
5.3%
3.2%
1.6%
Design:
A retrospective search was performed to identify pathology reports from patients who had an extended transrectal ultrasound guided prostate needle core biopsy at our institution between
1,668 prostate biopsies included in this 5 year study were submitted by 15 urologists.
Reports were analyzed for submitting urologist, number of containers submitted, total number of cores, individual core lengths, and diagnosis of cancer within a case and per container (carcinoma, negative, high grade prostatic intraepithelial neoplasia (HGPIN), atypical small acinar proliferation (ASAP), or HGPIN and ASAP (HGPIN/ASAP).
Within the time period of the study, 1 urologist decreased the number of submitted containers from to 6-9 for the sole purpose of reducing patient expenditures, with no other changes to his biopsy strategy. Results from these 2 subgroups were compared. A B
A and B: Total core length varied significantly with urologist. The above cases demonstrate total core length per case >25 cm (A) vs <15 cm (B).
Table 2: Average container number, total core length, and average longest core length varies significantly per urologist
Average Container Number
Average Total Core Length (cm)
Average Longest Core Length (cm)
Urologist 1
7.9
12.7
1.7
Urologist 2
12.0
15.5
Urologist 3
14.0
22.3
1.9
Urologist 4
8.9
18.9
Urologist 5
23.3
2.1
Conclusion:
Submitting urologist significantly impacted all variables included in this study.
These variables did not impact overall cancer detection per case, although core length per container did correlate with a diagnosis of cancer per container and therefore may be a quality assurance metric.
Reduction of the number of containers utilized in prostate biopsy submission is an opportunity for cost control. C D
C and D: Urologist 4 reduced container number from 14 to 8 during study period with no change in cancer detection rate. Case submitted in 14 containers (C) and 8 containers (D).
Table 3: Prostate core characteristics of the versus 6-9 container groups submitted by Urologist 4
12-14 Containers
6-9 Containers
Total Case Number 60
158
Average Container Number
13.9 8
Average Total Core Length
20.1 cm
18.4 cm
Average Longest Core Length
2.1 cm
1.9 cm E
Acknowledgement:
Funding provided by The Ohio State University Roessler Medical Student Scholarship and Medical Alumni Society Grant.
E: Longest individual core length varied significantly by urologist. The above images of slides from 2 separate cases demonstrate the variation in core lengths per container with a 0.2 cm core in the top slide and a 1.7 cm core in the bottom slide.