Results
Data from 457 patients who underwent RP after the diagnosis of PCa in
127 patients with combined TBx + SBx and 330 with conventional TRUS-Bx
method were evaluated. Patient demographics of the study cohort
stratiļ¬ed by biopsy approach are depicted in Table 1. Mean age and PSA
values between the groups were similar. The median number of targeted
biopsy cores sampled per region of interest (ROI) was 4 (range 2-7).
In the comparison of biopsy ISUP grades between TRUS-Bx and targeted
biopsies, higher ISUP grades were detected by combined TBx+SBx.
Significant cancer detection was 49.5 % for SBx, 67% for TBx and
highest 75.7% for Combination TBx+SBx. There was significant difference
in missed cancer ratio between TBx and SBx (10.2% vs 24.4%) that any
grade cancer detection by SBx alone was significantly lower than TBx
alone.
ISUP distributions and upgrade / downgrade ratios of the methods are
also given in Figures 1,2 and Tables 1. Overall Biopsy and surgical
pathologic ISUP Grade were concordant in 50% men of the TRUS-Bx and in
57.5 % of the combined TBX+SBx group (p=0.152). Gleason upgrading /
downgrading of at least one Gleason Grade Group (GGG) was recorded in
43.3% / 6.7 % patients of the TRUS-Bx, and in 20.5% / 22% of the
TBX+SBx group, respectively (all p <0.001).
In the evaluation of conventional TRUS-Bx method according to ISUP
grades, concordance achieved in 37.9%, 70%, and 56.1%, in ISUP 1, 2
and 3 grades respectively, at RP pathology. In the TRUS-Bx group, after
prostatectomy significant upgrading of 62.1% was detected in ISUP 1
grade.
For ISUP 1 grade, TBx+SBx and TBx showed significantly higher
concordance over SBx at RP (Figure 2). Concordance level was
significantly higher for ISUP 1 in combined TBx + SBx method compared to
conventional TRUS-Bx (61.3% vs 37.9%, p=0.014). In patients with
biopsy ISUP 1 exclusively, significant upgrading was seen in TRUS-Bx
(62.1%) and SBx (55.5%) when compared to TBx (41.4%) and TBx+SBx
(38.7%). Upgrading rates for ISUP 2 were similar in SBx, TBx, TBx+SBx.
However, for ISUP 2 downgrading rates were significantly higher in TBx
and TBx+SBx when compared to SBx alone. For ISUP Grade 2, SBx and
TRUS-Bx showed similar upgrading and downgrading rates. In ISUP 2, all
biopsy methods showed similar upgrading but downgrading was higher in
TBx and TBx+SBx probably due to over sampling tersiyer 4 pattern in
biopsy. Combined TBx+SBx showed significant downgrading in 47.8 % and
54.6 % for ISUP 3 and 4 respectively. For ISUP 3, 4, and 5 groups TBx,
SBx, and TBx+SBx showed similar concordances. No upgrading was detected
in SBx group for ISUP 3, 4 but downgrading was higher in SBx group when
compared to TBx and TBx+SBx . For ISUP grade 2, TRUS-Bx showed the
highest concordance among all biopsy methods (70%) with less
downgrading. For ISUP 2 and 3 TRUS-Bx showed superior but not
significant concordance than combined TBx + SBx method (70% vs 64.7%
p=0.509 and 56.1% vs 43.5%, p=0.332). For ISUP 3 and 4, TRUS-Bx showed
higher upgrading and less downgrading when compared to TBx+SBx.
Conventional TRUS-Bx showed the worst concordance with 17.6% at ISUP
Grade 4 with an upgrading rate of 47.1% which might be a reflection of
inadequate sampling.