TMPRSS2-ERG gene fusion in Turkish patients with localized prostate cancer: results of radical prostatectomy specimens.
OBJECTIVE
Our aim was to evaluate and determine the frequency of Transmembrane protease, serine 2 (TMPRSS2)-ERG fusion in Turkish patients with clinically localized prostate cancer by using immunohistochemistry and reveal its relationship with clinicopathologic variables.


METHODS
Radical prostatectomy specimens of 99 patients, who underwent radical retropubic prostatectomy for localized cancer, between January 2002 and December 2011 were analyzed in the study. To detect ERG fusions, monoclonal ERG antibodyclone ID: EPR3864 (Epitomics, San Diego, CA, USA) and monoclonal anti-ERG antibody (9FY) (BiocareMedical, LLC, USA) were used. The immunistochemical expression of ERG protein was assessed as positive or negative regardless of stain intensity. Patients' age, total and primary Gleason scores, PSA levels, prostate volumes, tumor volumes, tumor stages and perineural invasion status were analysed retrospectively. Total fusion rate and correlation between the variables and fusion were evaluated.


RESULTS
Mean age, prostate volume, tumor volume, PSA value of 99 patients were 62.02 years (±5.93), 50.02 cc (±20.67), 3.19 cc (±4.16), and 9.34 ng/mL (±3.37) respectively. TMPRSS2-ERG fusion was seen in 46 (46.5%) of 99 patients. When the variables analysed with independent samples t test to predict fusion (+) status, none of them was found to be statistically significant. When evaluated by logistic regression analysis for (+) or (-) status, only tumor stage was found to be statistically significantly correlated with fusion (p=0.049).


CONCLUSIONS
The incidence of TMPRSS-ERG fusion in patients with localised prostate cancer in our study with Turkish population was found as 46.5%. Only tumor stage correlated with TMPRSS2-ERG fusion.
Department of Urology, Gülhane Military Medical Academy Haydarpasa Training and Research Hospital, İstanbul, Turkey.
Ömer
Ö
Yılmaz
Department of Pathology, Gülhane Military Medical Academy Haydarpasa Training and Research Hospital, İstanbul, Turkey.
Ufuk
U
Berber
Clinic of Urology, Beytepe Military Hospital, Ankara, Turkey.
Sezgin
S
Okçelik
Department of Urology, Gülhane Military Medical Academy Haydarpasa Training and Research Hospital, İstanbul, Turkey.
Hasan
H
Soydan
Department of Urology, Gülhane Military Medical Academy Haydarpasa Training and Research Hospital, İstanbul, Turkey.
Ferhat
F
Ateş
Department of Urology, Gülhane Military Medical Academy Haydarpasa Training and Research Hospital, İstanbul, Turkey.
Kenan
K
Karademir
Prostate Ca; TMPRSS-ERG fusion gene; tumor stage