Radiol Oncol 2020; 54(2): 194-200. doi: 10.2478/raon-2020-0019
194
research article
Significance of nuclear factor - kappa beta 
activation on prostate needle biopsy samples 
in the evaluation of Gleason score 6 prostatic 
carcinoma indolence
Marko Zupancic1, Boris Pospihalj2, Snezana Cerovic3, Barbara Gazic4, Primoz Drev4, 
Marko Hocevar5, Andraz Perhavec5
1 Department of Urology, General Hospital Slovenj Gradec, Slovenj Gradec, Slovenia
2 Department of Pathology, General Hospital Slovenj Gradec, Slovenj Gradec, Slovenia
3 Institute of Pathology and Forensic Medicine, Military Medical Academy Belgrade, Belgrade, Serbia
4 Department of Pathology, Institute of Oncology Ljubljana, Ljubljana, Slovenia
5 Department of Surgical Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia
Radiol Oncol 2020; 54(2): 194-200.
Received 3 January 2020
Accepted 24 March 2020
Correspondence to: Marko Zupančič, M.D., M.Sc., Department of Urology, General Hospital Slovenj Gradec, Gosposvetska cesta 1, 
SI-2380 Slovenj Gradec, Slovenia. E-mail: marko.zupancic@sb-sg.si
Disclosure: No potential conflicts of interest were disclosed. 
Background. The goal of our study was to find out whether the immunohistochemical expression of nuclear factor-
kappa beta (NF-κB) p65 in biopsy samples with Gleason score 3 + 3 = 6 (GS 6) can be a negative predictive factor 
for Prostate cancer (PCa) indolence. 
Patients and methods. Study was conducted on a retrospective cohort of 123 PCa patients with initial total PSA ≤ 
10 ng/ml, number of needle biopsy specimens ≥ 8, GS 6 on biopsy and T1/T2 estimated clinical stage who underwent 
laparoscopic radical prostatectomy and whose archived formalin-fixed and paraffin-embedded (FFPE) prostate 
needle biopsy specimens were used for additional immunohistochemistry staining for detection of NF-κB p65. Both 
cytoplasmic and nuclear NF-κB p65 expression in biopsy cores with PCa were correlated with postoperative pathologi-
cal stage, positive surgical margins, GS and biochemical progression of disease. 
Results. After follow-up of 66 months, biochemical progression (PSA ≥ 0.2 ng/ml) occurred in 6 (5.1%) patients, 3 (50%) 
with GS 6 and 3 (50%) with GS 7 after radical prostatectomy. Both cytoplasmic and nuclear NF-κB p65 expressions 
were not significantly associated with pathological stage, positive surgical margin and postoperative GS. Patients with 
positive cytoplasmic NF-kB reaction had significantly more frequent biochemical progression than those with nega-
tive cytoplasmic NF-kB reaction with PSA 0.2 ng/ml as cutoff point (p = 0.015) and a trend towards more biochemical 
progression with PSA ≥ 0.05 ng/ml as cutoff point (p = 0.068).
Conclusions. Cytoplasmic expression of NF-κB is associated with more biochemical progression and might be an 
independent prognostic factor for recurrence-free survival (RFS), but further studies including larger patient cohorts 
are needed to confirm these initial results.
Key words: nuclear factor-kappa beta; prostatic cancer; Gleason 6; needle biopsy sample
Introduction
Prostate cancer (PCa) is the most common cancer in 
men in developed European countries, particularly 
those with a high proportion of elderly population, 
with incidence rate up to 189 per 100.000.1 In last 
two decades the disease has emerged as the most 
frequent cancer amongst men following rapid in-
creases in the detection of a substantial number of 
early-stage PCa, particularly due to the increased 
Radiol Oncol 2020; 54(2): 194-200.
Zupancic M et al. / Nuclera factor-kappa beta activation in Gleason 6 prostatic cancer 195
number of PSA t esting. Re cognizing that the ex-
pected men’s life is obviously increasing, PCa also 
means increasing financial burden for individual 
countries.2 Majority of men newly diagnosed with 
PCa will be candidates for primary curative thera-
py, either with radical prostatectomy or radiation, 
but many PCa, however, are low-grade, even indo-
lent and the number of newly diagnosed PCa far 
outnumbers the number of lethal cases. Indolent 
PCa may exist for a long period without causing 
any symptoms or death, so the prediction of low 
risk and indolent PCa is needed to avoid overtreat-
ment by unnecessary invasive therapies, and select 
men for active surveillance (AS).3-5 
The nuclear factor-kappa beta (NF-κB) family of 
transcription factors plays a crucial role in inflam-
mation as well as in the development and progres-
sion of cancer. Extensive evidence indicates that 
the NF-κB pathway is implicated in controlling the 
expression of genes involved in cell survival, pro-
liferation, angiogenesis, and invasion.6 Many stud-
ies indicate that activation of NF-κB signaling in 
PCa cells correlates with PCa progression, includ-
ing chemoresistance, advanced stage, biochemical 
progression, and metastatic spread.7-11 NF-κB is 
critical for human health, and aberrant NF-κB ac-
tivation contributes to development of various au-
toimmune, inflammatory and malignant disorders 
including rheumatoid arthritis, atherosclerosis, in-
flammatory bowel diseases, multiple sclerosis and 
malignant tumors.12 Despite the growing evidence 
for a role of NF-κB in prostate tumorigenesis and 
resistance to therapy, the mechanisms underlying 
the activation of NF-κB in PCa remain only par-
tially understood.
The main goal of our study was to find out 
whether the immunohistochemical expression of 
NF-κB p65 in biopsy samples with Gleason score 3 
+ 3 = 6 (GS 6) is inversely correlated with prostatic 
carcinoma indolence.
Patients and methods
Patients
Our study was based on a retrospective cohort 
of 178 consecutive PCa patients whose archived 
formalin-fixe d and paraffin-embedded (FFPE) 
prostate needle biopsy specimens were used for 
additional immunohistochemistry staining. All 
 consecutive patients underwent the extraperito-
neal laparoscopic radical prostatectomy (ELRP) 
or “nerve-sparing” extraperitoneal laparoscopic 
radical prostatectomy (N-S ELRP) without lymph 
node dissection between 2006 and 2012 as a first 
treatment of PCa. All patients were followed-up 
for at least five years after surgery at Department 
of Urology in General Hospital Slovenj Gradec. 
Hospital patient’s files were used for clinical data.
The inclusion criteria were total PSA ≤ 10 ng/ml, 
number of biopsy specimen ≥ 8, histopathological 
result of prostate cancer GS 6 on biopsy and T1/T2 
estimated clinical stage, based on clinical examina-
tion only. The exclusion criterion was the presence 
of chronical diseases in which the activation of NF-
kB is common. After the screening review of the 
clinical data and histopathological revision of pros-
tate needle biopsy specimens, done by two unrelat-
ed pathologists with extensive experience in PCa, 
15 patients were excluded from the study, as they 
did not meet the criterion of GS. During the addi-
tional microtome cutting of archived FFPE prostate 
needle biopsy specimens for immunohistochemis-
try due to the lack of the tissue, another 40 patients 
were excluded. The final analysis in this study was 
performed on 123 patients. Based on a PSA levels, 
two biochemical progression were defined, at PSA 
cutoff point ≥ 0.05 ng/ml and ≥ 0.2 ng/ml, 6 months 
or more after radical prostatectomy. Recurrence-
free survival (RFS) was defined as the period be-
tween the surgery and biochemical progression 
(i.e. first increase of PSA above one or both PSA 
cutoff points). 5 patients were excluded due to the 
initiation of hormonal treatment immediately after 
surgery, so regarding the biochemical progression 
118 patients were analyzed 
For control group archived FFPE prostate nee-
dle biopsy specimens from 60 patients with PCa GS 
7, 30 with 3 + 4 and 30 with 4 + 3, were used.
Study was approved by the Slovene National 
Medical Ethics Committee No 109/14.
Tissue preparation and immuno-
histochemical staining
IHC staining for detection of NF-κβ p65 was per-
formed on 2-4 μm FFPE tissue sections, dried at 
56⁰C for 2 hours, using fully automated IHC system 
Ventana Benchmark XT (manufacturer Ventana 
ROCHE inc.). Epitope was retrieved on board em-
ploying heat-mediated epitope retrieval using high 
pH Cell Conditioning Solution 1 (cat No 950-124, 
manufacturer Ventana ROCHE inc.) for 88 minutes 
at 100⁰C. Epitope was detected using commercially 
available mouse monoclonal antibody NF-κβ p65 
(clone F-6; cat No sc-8008; manufacturer Santa 
Cruz Biotechnology inc.) directed against amino 
acids 1-286 of NF-κβ p65 of human origin. Primary 
Radiol Oncol 2020; 54(2): 194-200.
Zupancic M et al. / Nuclera factor-kappa beta activation in Gleason 6 prostatic cancer196
antibody was diluted 1:200 using DAKO REAL™ 
antibody diluent (cat No S2022; manufacturer 
DAKO Agilent technologies inc.) and incubated 
on board for 60 minutes at 37⁰C. Primary antibody 
was visualized using 3–step multimer detection 
system OptiView DAB IHC Detection Kit (cat No 
TABLE 1. Patient characteristics
General, N = 123
Mean Age, year, (range)  63.6 (50–75)
Mean init. PSA, ng/ml, (range)  5.32 (1,32–9,51)
Mean Prostate V, ml, (range)  38.3 (14–97)
Mean Biopsy cores, n, (range)  9.6 (8–10)
Total Biopsy cores, n 1.180
Clinical stage
 T1, n, (%)  113 (91.9)
 T2, n, (%)  10 (8.1)
Biopsy GS 3+3=6, n, (%)  123 (100)
Surgery
 ELRP, n, (%)  87 (70.7)
 N-S ELRP, n, (%)  36 (29.3)
Pathological result after RP
N = 123 N of total P % of total P
pT classification
 T2  96 78.0
 T3a
 T3b
 23
 4
18.7
 3.3
Surgical margins
 Positive  13 10.6
 Negative 110 89.4
Gleason score
 3+3=6  79 64.2
 3+4=7  37 30.1
 4+3=7  7  5.7
Biochemical progression after RP
N = 118 N (%) GS 6 GS 7
BP N( %) N( %)
PSA 0,05–0.19 ng/ml 14 (11.8) 8(57.1) 6(42.9)
 PSA ≥ 0,2 ng/ml 6 (5.1) 3(50) 3(50)
BP = biochemical progression; ELRP = laparoscopic radical prostatectomy; GS = Gleason score; 
N-S ELRP = “nerve-sparing” extraperitoneal laparoscopic radical prostatectomy; PSA = Prostate-
specific antigen; RP = radical prostatectomy; V = volume 
760-700; manufacturer Ventana ROCHE inc.) ac-
cording to manufacturer’s instructions.
The staining was analysed by pathologist with 
extensive experience in PCa who was not familiar 
with patient’s clinical data. For nuclear staining, 
positive result was reported when at least 5% nu-
clei of cancer cells showed unequivocal brown col-
oration.13 To consider reaction as positive, nuclear 
brown coloration should exceed the effect of cyto-
plasmic overlapping. The intensity of cytoplasmic 
staining was assessed as negative, weak, moderate 
and strong, and for statistical analysis grouped as 
negative (negative, weak) and positive (moderate, 
strong).14
Statistical analyses
Clinical, laboratory and pathological characteris-
tics were summarized using frequency and per-
centage for categorical variables, and mean and 
range for continuous variables. RFS was calcu-
lated from the time of primary tumour excision, 
and was censored at the last contact date if there 
were no events. Association of NF-kB expression 
status with pathological findings was tested using 
Chi-square test. Survival curves were calculated by 
Kaplan-Meier’s method and tested for statistical 
significance using log-rank test. Multivariate Cox 
regression model was used to test whether NF-
kB expression status is an independent predictor 
of RFS; other covariates included in the model are 
known prognostic factors in prostate cancer: final 
Gleason score, surgical margin status and patho-
logic stage. The differences were considered sta-
tistically significant if the p values were less than 
0.05. Software package SPSS 22.0 for Windows was 
used.
Results
Table 1 shows patients characteristics and bio-
chemical progression in patients after radical pros-
tatectomy. Postoperative pathological stage 3 was 
noticed in 27 (22%) and positive surgical margins 
were detected in 13 patients (10.6%). biochemi-
cal progression (PSA ≥ 0.05 ng/ml) occurred in 20 
(16.9%) patients (11 with GS 6 after radical pros-
tatectomy and 9 with GS 7). Among 118 patients, 
clinically significant postoperative PSA ≥ 0.2 ng/ml 
was detected in six patients (5.1%), with GS 6 in 3 
and GS 7 in 3. Positive cytoplasmic NF-κB staining 
was detected in 173 (56.9%) and positive nuclear 
Radiol Oncol 2020; 54(2): 194-200.
Zupancic M et al. / Nuclera factor-kappa beta activation in Gleason 6 prostatic cancer 197
NF-κB p65 expression was significantly more 
common in biochemical progression with PSA cut 
off point ≥ 0.2 ng/ml (P = 0.015) and there was a 
trend towards biochemical progression with PSA 
cut off point ≥ 0.05 ng/ml (P = 0.068) (Figure 1). 
Cytoplasmic NF-κB p65 expression was positive 
in 57/60 control group patients with GS 7 (Table 3).
In multivariate analysis only positive surgical 
margin was significantly associated with worse 
RFS with a PSA cut off point ≥ 0.05 ng/ml, while 
postoperative Gleason score 7 and pathologic stage 
of the disease were not significantly associated 
with RFS (Table 4). Positive cytoplasmic NF-κB p65 
expression negatively affects RFS with borderline 
statistical significance (p = 0.078). When PSA cut off 
point was set to ≥ 0.2 ng/ml, none of the prognos-
tic factors was significantly associated with RFS in 
multivariate analysis.
Nuclear NF-κB staining
Nuclear NF-κB p65 expression was not associated 
with pathological stage, positive surgical margins 
and postoperative GS (Table 5), neither with bio-
chemical progression (Figure 2) and did not differ 
from control group patients with GS 7 (Table 6).
TABLE 2. Association of nuclear factor-kappa beta (NF-κB) p65 
expression status in cytoplasm with pathological findings
N = 123 N 
NF-κB p65 expression
P
negative positive
pT status
pT2 96 48  48
pT3 27 12  15 0.667*
Surg. m.
Negative 110 53  7
Positive  13  7  6 0.774**
GS
3 + 3 = 6 79 39  40
3 + 4 = 7 37 17  20
4 + 3 = 7 7  5  2 0.465***
* pT2 versus pT3, **negative versus positive surgical margin, ***3 + 3 = 6 
versus 3 + 4 = 7 versus 4 + 3 = 7
GS = Gleason score; Surg. M. = surgical margin
TABLE 3. Cytoplasmic nuclera factor-kappa beta (NF-κB) p65 
expression status in biopsy group postoperative Gleason score 
(GS) 6 and control biopsy group p ostoperative GS 7
N 
NF-κB p65 expression
P
negative positive
3 + 3 = 6 123 60  63
3 + 4 = 7 30  3  27 <0.001*
4 + 3 = 7 30  0  30 <0.001**
* 3 + 3 = 6 versus 3 + 4 = 7, **3 + 3 = 6 versus 4 + 3 = 7
FIGURE 1. Recurrence-free survival (RFS) in patients with positive and negative nuclear factor-kappa beta (NF-κB) p65 expression 
status in cytoplasm (N = 118).
NF-κB staining in 57 (18.7%) of the 304 analyzed 
biopsy cores with GS 6. 
Cytoplasmic NF-κB staining
Cytoplasmic NF-κB p65 expression was not corre-
lated with pathologic al stage, positive surgical mar-
gin and postope rative GS (Table 2). Cytoplasmic 
TABLE 4. Multivariate analysis of cytoplasmic nuclear factor-
kappa beta (NF-κB) p65 expression and other clinicopathologic 
variables associated with recurrence-free survival (RFS)
Hazard ratio 
(95% CI) P
Cytoplasmic 
NF-κB p65 expression 
(negative vs. positive)
2.367 (0.908–6.170) 0.078
Postoperative 
Gleason score (6 vs. 7) 1.105 (0.406–3.008) 0.845
Surgical margin 
(negative vs. positive) 4.845 (1.646–14.260) 0.004
Pathologic stage 
(T2 vs. T3) 1.041 (0.339–3.194) 0.944
Radiol Oncol 2020; 54(2): 194-200.
Zupancic M et al. / Nuclera factor-kappa beta activation in Gleason 6 prostatic cancer198
In multivariate analysis only positive surgical 
margin was significantly associated with worse 
RFS with a PSA cut off point ≥ 0.05 ng/ml, while 
positive nuclear NF-κB p65 expression, postopera-
tive Gleason score 7 and pathologic stage of the 
disease were not significantly associated with RFS 
(Table 7). When PSA cut off point was set to ≥ 0.2 
ng/ml, none of the prognostic factors was signifi-
cantly associated with RFS in multivariate analysis. 
Figure 3 shows difference in positive cytoplasmic 
and nuclear staining in patient with GS 6 and GS 7.
Discussion
Increase in incidence of PCa since 1990s mostly 
starts with PSA testing, either in the form of all 
types of screening or on the basis of a suspicious 
digital rectal examination. Nevertheless, the most 
important part of diagnostic procedure is accurate 
histopathologic diagnosis, particularly in low-risk 
PCa where AS could be an option.15 Despite the fact 
that in our study biopsy samples were evaluated 
by two experienced uropathologists, we recorded 
the postoperative upgrade of GS 6 to GS 7 in 44 
patients (3 + 4 in 37 and 4 + 3 in 7), so biopsy under-
grading was present in 35.8%. This is in concord-
ance with literature reports where GS from needle 
biopsies underestimates the GS of the radical pros-
tatectomy specimen in 28% to 57%.16 Postoperative 
pathological stage 3 was noticed in 27 (22%), posi-
tive surgical margins were detected in 13 (10.6%) 
FIGURE 2. Recurrence-free survival (RFS)  in patients with positive and negative nuclear factor-kappa beta (NF-κB) p65 expression 
status in nucleus (N = 118).
TABLE 5. Association of nuclear factor-kappa beta (NF-κB) p65 
expression status in nucleus with pathological findings
N = 123 N 
NF-κB p65 expression
P
negative positive
pT status
pT2 96 81 15
pT3 27 22 5 0.769*
Surg. m.
Negative 110 92 18
Positive  13 11  2 1**
GS
3 + 3 = 6 79 66 13
3 + 4 = 7 37 31  6
4 + 3 = 7 7  6  1 0.989***
* pT2 versus pT3, **negative versus positive surgical margin, *** 3 + 3 = 6 
versus 3 + 4 = 7 versus 4 + 3 = 7
GS = Gleason score; Surg. M. = surgical margin
TABLE 6. Nuclear factor-kappa beta (NF-κB) p65 expression 
status in biopsy group GS 6 and control biopsy group GS 7
N 
NF-κB p65 expression
P
negative positive
3+3=6 123 103 20
3+4=7 30 24 6  0.596*
4+3=7 30 17 13  0.003**
* 3+3=6 versus 3+4=7, **3+3=6 versus 4+3=7
TABLE 7. Multivariate analysis of nuclear factor-kappa beta 
(NF-κB) p65 expression and other clinicopathologic variables 
associated with recurrence-free survival (RFS; recurrence 
defined as PSA ≥ 0.05)
Hazard ratio
(95% CI) P
NF-κB p65 expression
(negative vs. positive) 0.254 (0.034–1.915) 0.184
Postoperative Gleason 
score (6 vs. 7) 1.078 (0.400–2.907) 0.882
Surgical margin 
(negative vs. positive) 4.838 (1.674–13.983) 0.004
Pathologic stage 
(T2 vs. T3) 1.232 (0.409–3.705) 0.711
Radiol Oncol 2020; 54(2): 194-200.
Zupancic M et al. / Nuclera factor-kappa beta activation in Gleason 6 prostatic cancer 199
and clinically significant biochemical progression 
(PSA ≥ 0.2 ng/ml) in 6 (5.1%) patients. 
Molecular biomarkers offer the possibility to 
further stratify patients with similar clinicopatho-
logical parameters. Domingo-Domenech et al.9 and 
Ross et al.10 reported that tumors with nuclear NF-
κB expression and no additional risk factors (i.e. 
low GS and low preoperative PSA) had the lowest 
rate of biochemical recurrence in the nuclear NF-
κB positive group. In addition to nuclear staining, 
we included also the NF-κB cytoplasmic staining 
and contrary to reported results found that only 
the cytoplasmic NF-κB variable was associated 
with worse RFS. This association was statistically 
significant when PSA cut-off point for recurrence 
was set to ≥ 0.2 ng/ml (p = 0.013) and borderline sig-
nificant when PSA cut-off point was set to ≥ 0.05 (p 
= 0.057). In multivariate analysis positive cytoplas-
mic NF-κB p65 expression remained negatively as-
sociated with RFS (PSA cut-off point ≥ 0.05) with 
borderline statistical significance (p = 0.078). 
The p65 subunit of NF-κB was expressed in the 
cytoplasm of 173 (56.9%) biopsy cores with GS 6. 
Only 57 (18.7%) biopsy samples also showed a 
nuclear staining of NF-κB p65, suggesting a con-
stitutive activation of NF-κB in these tissues. Our 
results showed a positive correlation between 
NF-κB cytoplasmic staining and biochemical pro-
gression. The main differences with other studies 
relate to tissue sample type and biochemical pro-
gression definition. Unlike Domingo-Domenech 
et al.9 and Ross et al.10 the studies that used tissue 
samples from radical prostatectomy, our analysis 
is preoperative and is based on diagnostic biopsies 
and their predictive significance. Also, we used 
more stringent parameters for the determination of 
biochemical progression, which in previous works 
was only determined as a value of 0.4 ng/ml in two 
consecutive measurements. In the present study, 
NF-κB expression and its subcellular localization 
were highly variable among different specimens. 
In another study, nuclear NF-κB was found in 40% 
of PCa.8-13 As in the current study, nuclear NF-κB 
did not significantly correlate with GS. The func-
tional relevance of this immunoreactivity on NF-
κB activation is not known. This limitation is based 
on the fact that p65/NF-κB nuclear translocation 
is necessary but not sufficient for NF-κB induced 
transcriptional activity, since both recruitment of 
NF-κB to target genes and NF-κB-induced tran-
scriptional events after recruitment are needed 
for this to occur. Furthermore, the minimum per-
centage of tumor cells with nuclear p65 staining 
required to potentially result in detectable NF-κB-
induced transcriptional activity remains uncharac-
terized. An important limitation of our study is a 
significant reduction in the size of diagnostic biop-
sies during microscopic reevaluation and diagno-
sis of PCa with GS 6.13,14
In our group of 20 patients who developed the 
biochemical progression with PSA cutoff point 
≥ 0.05 ng/ml cytoplasmic NF-κB staining was de-
tected in 14 (70%) and nuclear NF-κB staining in 
only 1 (5%), while among those 6 patients who 
had the biochemical progression with PSA cutoff 
point ≥ 0.2 ng/ml cytoplasmic NF-κB staining was 
noticed in all 6 (100%) and nuclear NF-κB staining 
in 1 (16.7%). Among several available selection cri-
teria for AS worldwide, at our institution the EAU 
AS guidelines were used.17 According to them all 
patients in our cohort had initial PSA below 10 ng/
ml, biopsy GS 6, estimated clinical stage T1c-T2 
and 82 of them (66.7%) had ≤ 2 positive cores on 
biopsy. From clinical point of view the biochemical 
progression of PCa after radical prostatectomy is 
defined with PSA ≥ 0.2 ng/ml.18 In our group of 6 
patients with biochemical progression at PSA cut-
off point ≥ 0.2 ng/ml, positive cytoplasmic NF-κB 
staining was present in all 6 and all AS criteria were 
met in 5 (83.3%) patients. There was no positive nu-
clear NF-κB staining in any of these 5 patients. As 
a control group we used 60 patients with biopsy 
GS 7 and positive cytoplasmic NF-κB staining was 
present in 57 (95%) of them. Since patients with bi-
FIGURE 3. Immunohistochemistry of nuclear factor-kappa beta (NF-κB) p65. (A) 
Positive cytoplasmic staining (GS 6). (B) Positive nuclear staining. (C) Positive 
cytoplasmic staining (GS 7). (D) Positive nuclear staining.
A B
C D
Radiol Oncol 2020; 54(2): 194-200.
Zupancic M et al. / Nuclera factor-kappa beta activation in Gleason 6 prostatic cancer200
opsy GS 7 are not candidates for AS according to 
EAU AS guidelines there is no need for additional 
prognostic factor (i.e. positive cytoplasmic NF-κB 
staining). However, in patients with biopsy GS 6, 
an additional prognostic factor is needed in order 
to stratify these patients to a group where only AS 
is enough. According to our results, positive cyto-
plasmic NF-κB staining could be a negative predic-
tive factor for the GS 6 PCa indolence and these pa-
tients are candidates for primary curative therapy.
There are several limitations of our study. Most 
importantly, all patients underwent surgical treat-
ment, so the significance of NF-κB activation on 
prostate needle biopsy samples for disease pro-
gression was found only indirectly, based on bio-
chemical progression and is most probably under-
estimated. Another important limitation is a small 
number of patients and single institution results.
Conclusions
Cytoplasmic expression of NF-κB is associated 
with worse RFS, while it is not significantly associ-
ated with standard prognostic factors and remains 
an independent prognostic factor for RFS in multi-
variate analysis with borderline statistical signifi-
cance. However, further studies, including larger 
patient cohorts are needed to confirm these initial 
results.
References
1. Ferlay J, Colombet M, Soerjomataram I, Dyba T, Randi G, Bettio M, et al. 
Cancer incidence and mortality patterns in Europe: Estimates for 40 coun-
tries and 25 major cancers in 2018. Eur J Cancer 2018; 103: 356-87. doi: 
10.1016/j.ejca.2018.07.005.
2. Luengo-Fernandez R, Leal J, Gray A, Sullivan R. Economic burden of cancer 
across the European Union: a population-based cost analysis. Lancet Oncol 
2013; 14: 1165-74. doi: 10.1016/S1470-2045(13)70442-X.
3. Cooperberg MR, Broering JM, Litwin MS, Lubeck DP, Mehta SS, Henning 
JM, et al. The contemporary management of prostate cancer in the United 
States: lessons from the cancer of the prostate strategic urologic research 
endeavor (CapSURE), a national disease registry. J Urol 2004; 171: 1393-401. 
doi: 10.1097/01.ju.0000107247.81471.06
4. Albertsen PC, Hanley JA, Fine J. 20-year outcomes following conservative 
management of clinically localized prostate cancer. JAMA 2005; 293: 2095-
101. doi: 10.1001/jama.293.17.2095
5. Bangma CH, Roobol MJ. Defining and predicting indolent and low risk 
prostate cancer. Crit Rev Oncol Hematol 2012; 83: 235-41. doi: 10.1016/j.
critrevonc.2011.10.003
6. Karin M, Lin A. NF-κB at the crossroads of life and death. Nat. Immunol 
2002; 3: 221-7. doi: 10.1038/ni0302-221
7. May MJ, Ghosh S. Rel/NF-kappa B and I kappa B proteins: an overview. 
Semin Cancer Biol 1997; 8: 63-73. doi: 10.1006/scbi.1997.0057
8. Lessard L, Karakiewicz PI, Bellon-Gagnon P, Alam-Fahmy M, Ismail HA, 
Mes-Masson AM, et al. Nuclear localization of nuclear factor-kappaB p65 in 
primary prostate tumors is highly predictive of pelvic lymph node metasta-
ses. Clin Cancer Res 2006; 12: 5741-5. doi: 10.1158/1078-0432.CCR-06-0330
9. Domingo-Domenech J, Mellado B, Ferrer B, Truan D, Codony-Servat J, 
Sauleda S, et al. Activation of nuclear factor-kappaB in human prostate 
carcinogenesis and association to biochemical relapse. Br J Cancer 2005; 93: 
1285-94. doi: 10.1038/sj.bjc.6602851
10. Ross JS, Kallakury BV, Sheehan CE, Fisher HA, Kaufman RP Jr, Kaur P, et 
al. Expression of nuclear factor-kappa B and I kappa B alpha proteins in 
prostatic adenocarcinomas: correlation of nuclear factor-kappa B immuno-
reactivity with disease recurrence. Clin Cancer Res 2004; 10: 2466-72. doi: 
10.1158/1078-0432.ccr-0543-3
11. Setlur SR, Royce TE, Sboner A, Mosquera JM, Demichelis F, Hofer MD, et 
al. Integrative microarray analysis of pathways dysregulated in metastatic 
prostate cancer. Cancer Res 2007; 67: 10296-303. doi: 10.1158/1078-0432.
ccr-0543-3
12. Park MH, Hong JT. Roles of NF-κB in cancer and inflammatory diseases and 
their therapeutic approaches. Cells 2016; 5: E15. doi: 10.3390/cells5020015.
13. Lessard L, Begin LR, Gleave ME, Mes-Masson AM, Saad F. Nuclear localisa-
tion of nuclear factor-kappaB transcription factors in prostate cancer: an 
immunohistochemical study. Br J Cancer 2005; 93: 1019-23. doi: 10.1038/
sj.bjc.6602796
14. Gannon PO, Lessard L, Stevens LM, Forest V, Bégin LR, Minner S, et al. Large-
scale independent validation of the nuclear factor-kappa B p65 prognostic 
biomarker in prostate cancer. Eur J Cancer 2013; 49: 2441-8. doi: 10.1016/j.
ejca.2013.02.026
15. Ganz PA, Barry JM, Burke W, Col NF, Corso PS, Dodson E, et al. NIH State-
of-the-Science Conference Statement: role of active surveillance in the 
management of men with localized prostate cancer. NIH Consens State Sci 
Statements 2011; 28: 1-27. PMID: 23392076
16. Lucia MS, Bostwick DG, Somerville MC, Fowler IL, Rittmaster RS. Comparison 
of classic and international society of urological pathology 2005 modified 
Gleason grading using needle biopsies from the reduction by dutasteride 
of prostate cancer events (REDUCE) trial. Arch Pathol Lab Med 2013; 137: 
1740-6. doi: 10.5858/arpa.2012-0447-OA
17. Komisarenko M, Martin LJ, Finelli A. Active surveillance review: contempo-
rary selection criteria, follow-up, compliance and outcomes. Transl Androl 
Urol 2018; 7: 243-55. doi: 10.21037/tau.2018.03.02
18. McCormick BZ, Mahmoud AM, Williams SB, Davis JW. Biochemical recur-
rence after radical prostatectomy: Current status of its use as a treatment 
endpoint and early management strategies. Indian J Urol 2019; 35: 6-17. 
doi: 10.4103/iju.IJU_355_18