| Abstract | Uvod: Rak prostate je među najčešćim zloćudnim bolestima u muškaraca i jedan je od vodećih
zdravstvenih problema muškaraca starije životne dobi. Hrvatski registar za rak svrstao je
karcinom prostate na prvo mjesto po učestalosti te drugo mjesto po smrtnosti od malignih bolesti
muškaraca. Jedan od preferiranih standardnih oblika liječenja lokaliziranog karcinoma prostate je
radikalna radioterapija. Učinkovitost liječenja radioterapijom ograničena je toksičnim
nuspojavama. Osim toga stanice raka razvijaju mehanizme radiorezistencije povezane s
popravkom DNA, inhibicijom apoptoze ili promjenama u staničnom ciklusu. Biomarkeri koji
sudjeluju u spomenutim staničnim mehanizmima (p53, bcl-2, NF-kb, Cripto-1), slabo su
izučavani u dosadašnjoj literaturi, u korelaciji s kliničko-patološkim parametrima (vrijednost
PSA, Gleason zbroj, gradusna i prognostička grupa, stadij bojesti, indeks proliferativne
akitvnosti-Ki67) u bolesnika s radiorezistentnim tumorima
Cilj: Validirati imunohistokemijsku ekspresiju: p53, bcl-2, NF κB, Cr -1 u tkivnim mikroarejama
karcinoma prostate bolesnika liječenih radikalnom radioterapijom. Odrediti međusobnu
povezanost imunohistokemijskih parametara s kliničko-patološkim karakteristikama te
povezanost kliničko-patoloških karakteristika i imunohistokemijskih biomarkera s ishodima
liječenja radioterapijom, u vidu progresije bolesti (pojava metastaza), preživljenja bez bolesti i
ukupnoga preživljenja.
Materijal i postupci: Pregledom medicinskih podataka Klinike za tumore KBC Rijeka izabrano
je 90 bolesnika s karcinom prostate liječenih radikalnom radioterapijom (ukupna doza 64 Gy) i
praćeni najmanje 48 mjeseci. Pacijenti uključeni u ovu retrospektivnu studiju imali su tumore
ograničene na prostatu ili lokalno uznapredovalu bolest koji su imali patohistološki uzorak
adekvatan za imunohistokemijsku analizu te oni s potpunim medicinskim podacima.
Za navedene bolesnike odabran je patohistološki materijal na Zavodu za patologiju KBC Rijeka
za izradu tkivnih mikroareja koji su potom imunohistokemijski obojani protutijelima za p53,
bcl-2, NFκB i Cr -1. Progresija bolesti se određivala pojavom metastaza, a podatci dobiveni
očitanjem u vidu postotka pozitivnog imunohistokemijskog obojenja na 500 stanica obrađeni su
standardnim statističkim metodama.
Rezultati: Potvrdili smo već dobro poznatu statistički značajnu povezanost stadija bolesti s
Gleason zbrojem i prognostičkom grupom. Viši stadij bolesti u prosjeku znači i povećani Gleason zbroj te višu prognostičku grupu. Gradus grupa nije bila povezana samo sa stadijem,
dok se kod ostalih parametara našla statististički značajna pozitivna korelacija. Izražaj p53
statistički je bio značajno povezan sa stadijem bolesti i gradus grupom, pri čemu je izražaj u
prvom stadiju i nižoj gradus grupi bio niži od izražaja u trećem stadiju. Izražaj nfκb bio je
povezan je samo s prognostičkom grupom, pri čemu se kod prognostičkih grupa 1 i 2 nalazio
statistički značajno manji izražaj nego kod grupa 4 i 5. Logrank test je pokazao da je gradus
grupa povezana s preživljenjem, a analiza omjera rizika statistički značajnu razliku između prve i
druge te prve i pete gradus grupe . Također, statistički značajna povezanost progresije bolesti i
izražaja nfκb i Ki67 je utvrdila najbolji prediktivni potencijal, pri čemu je kod nfκB naglasak
bio na osjetljivosti, a kod Ki67 na specifičnosti. Izražaj Cr-1 nije bio statistički značajno povezan
niti s jednim od promatranih parametara iako je u analizi progresije bolesti pokazao visoku
osjetljivost, dok su p53 i bcl2 imali visoku specifičnost. Multivarijatna analiza u odnosu na
petogodišnji period bez progresije bolesti je pokazala je značajnu prediktivnu vrijednost
imunohistokemijskih parametara p53, Nfkb, bcl procjenom razina ova tri biomarkera zajedno,
ali ne i pojedinačno. Preživljenje je očekivano bilo povezano s kliničko patološkim parametrima
te s proliferativnom aktivnošću tumora tj.Ki67 imunoizražajem.
Zaključak: Rezultati studije su potvrdili utjecaj izražaja p53, bcl-2, nfκb, Cr -1 na ishod
liječenja radioterapijom. Biomarkeri nfκb i Ki67 su pokazali najbolji prediktivni potencijal
progresije bolesti. Svi validirani imuohistokemijski parametri su potvrdili određenu povezanost s
preživljenjem, ali je samo Ki67 indeks proliferacije bio statistički značajan. Konstruiranjem
numeričkog indeksa utemeljenog na svim kliničko-patološkim i imunohistokemijskim
parametrima, utvrđen je granični rezultat >21 ili više kao pokazatelj značajnog rizika za
progresiju. U slučaju numeričkog indeksa većeg od 21 bolesnik je u većem riziku od progresije
bolesti nakon završetka liječenja radioterapijom te bi se trebali pažljivije pratiti. |
| Abstract (english) | Introduction: Prostate cancer is among the most common malignant diseases in men and is one
of the leading health problems of older men. The Croatian Cancer Registry ranked prostate
cancer first in terms of frequency and second in terms of mortality from malignant diseases in
men. One of the preferred standard forms of treatment for localized prostate cancer is radical
radiotherapy. The effectiveness of radiotherapy treatment is limited by toxic side effects. In
addition, cancer cells develop mechanisms of radioresistance associated with DNA repair,
inhibition of apoptosis or changes in the cell cycle. In the literature biomarkers that participate
in those cellular mechanisms (p53, bcl-2, NF-kb, Cripto-1) have been poorly correlated with
clinical and pathological parameters (PSA value, Gleason score, grade and prognostic group,
stage bojesti, proliferative activity index-Ki67) in patients treated with radiotherapy.
Objective: To validate the immunohistochemical expression of: p53, bcl-2, NF κB, Cr -1 in
tissue microarrays of prostate cancer patients treated with radical radiotherapy. To determine the
relationship between immunohistochemical parameters and clinical-pathological characteristics
and the relationship between clinical-pathological characteristics and immunohistochemical
biomarkers with radiotherapy treatment outcomes, in the form of disease progression
(appearance of metastases), disease-free survival and overall survival.
Material and procedures: 90 patients with prostate cancer treated with radical radiotherapy
(total dose 64 Gy) and followed for at least 48 months, were selected by reviewing the medical
data of the KBC Rijeka Tumor Clinic. Patients included in this retrospective study had tumors
confined to the prostate or locally advanced disease who had a pathohistological specimen
adequate for immunohistochemical analysis and those with complete medical data.
Pathohistological material of those patients was selected at the Department of Pathology of KBC
Rijeka for the creation of tissue microarrays, which were then immunohistochemically stained
with antibodies for p53, bcl-2, NFκB and Cr-1. The progression of the disease was determined
by the appearance of metastases, and the data obtained from the pathologist by analizing the
percentage of positive immunohistochemical staining on 500 cells were processed using standard
statistical methods.
Results: We confirmed the already well-known statistically significant association of disease
stage with Gleason score and prognostic group. A higher stage of the disease means, on average,an increased Gleason score and a higher prognostic group. Gradus group was not only related to
stage, while a statistically significant positive correlation was found with other parameters. The
expression of p53 was statistically significantly related to the stage of the disease and the grade
group, whereby the expression in the first stage and the lower grade group was lower than the
expression in the third stage. The expression of nfκb was only related to the prognostic group,
where in prognostic groups 1 and 2 there was a statistically significantly lower expression than in
groups 4 and 5. The logrank test showed that the grade group was associated with survival, and
the risk ratio analysis was statistically significant the difference between the first and second and
first and fifth grade groups. Also, the statistically significant association between disease
progression and the expression of nfκb and Ki67 determined the best predictive potential, with
nfκB emphasizing sensitivity and Ki67 specificity. The expression of Cr-1 was not statistically
significantly related to any of the observed parameters, although in the analysis of disease
progression it showed high sensitivity, while p53 and bcl2 had high specificity. Multivariate
analysis in relation to the five-year period without disease progression showed a significant
predictive value of the immunohistochemical parameters p53, Nfkb, bcl by assessing the levels
of these three biomarkers together, but not individually. As expected, survival was related to
clinicopathological parameters and tumor proliferative activity, i.e. Ki67 immunoexpression.
Conclusion: The results of the study confirmed the impact of the expression of p53, bcl-2, nfκb,
Cr -1 on the outcome of radiotherapy treatment. Biomarkers nfκb and Ki67 showed the best
predictive potential of disease progression. All validated immunohistochemical parameters
confirmed a certain association with survival, but only the Ki67 proliferation index was
statistically significant. By constructing a numerical index based on all clinical-pathological and
immunohistochemical parameters, a threshold score of >21 or more was established as an
indicator of a significant risk for progression. In the case of a numerical index greater than 21,
the patient is at greater risk of disease progression after completion of radiotherapy treatment and
should be monitored more carefully.
Key words: an increased Gleason score and a higher prognostic group. Gradus group was not only related to
stage, while a statistically significant positive correlation was found with other parameters. The
expression of p53 was statistically significantly related to the stage of the disease and the grade
group, whereby the expression in the first stage and the lower grade group was lower than the
expression in the third stage. The expression of nfκb was only related to the prognostic group,
where in prognostic groups 1 and 2 there was a statistically significantly lower expression than in
groups 4 and 5. The logrank test showed that the grade group was associated with survival, and
the risk ratio analysis was statistically significant the difference between the first and second and
first and fifth grade groups. Also, the statistically significant association between disease
progression and the expression of nfκb and Ki67 determined the best predictive potential, with
nfκB emphasizing sensitivity and Ki67 specificity. The expression of Cr-1 was not statistically
significantly related to any of the observed parameters, although in the analysis of disease
progression it showed high sensitivity, while p53 and bcl2 had high specificity. Multivariate
analysis in relation to the five-year period without disease progression showed a significant
predictive value of the immunohistochemical parameters p53, Nfkb, bcl by assessing the levels
of these three biomarkers together, but not individually. As expected, survival was related to
clinicopathological parameters and tumor proliferative activity, i.e. Ki67 immunoexpression.
Conclusion: The results of the study confirmed the impact of the expression of p53, bcl-2, nfκb,
Cr -1 on the outcome of radiotherapy treatment. Biomarkers nfκb and Ki67 showed the best
predictive potential of disease progression. All validated immunohistochemical parameters
confirmed a certain association with survival, but only the Ki67 proliferation index was
statistically significant. By constructing a numerical index based on all clinical-pathological and
immunohistochemical parameters, a threshold score of >21 or more was established as an
indicator of a significant risk for progression. In the case of a numerical index greater than 21,
the patient is at greater risk of disease progression after completion of radiotherapy treatment and
should be monitored more carefully. |
