A comparison of the biological features between prostate cancers arising in the transition and peripheral zones.
OBJECTIVE
To investigate differences in the biological features of prostate cancer according to the zonal origin.


METHODS
Among 172 consecutive patients who had a radical prostatectomy (RP), the study included 124 diagnosed as having either transition zone (TZ) or peripheral zone (PZ) cancer, defined according to whether there was > 70% of the cancer area in the TZ or PZ, respectively. The clinicopathological features were then compared between these groups. In addition, the RP specimens were stained immunohistochemically with antibodies to Ki-67, Bcl-2, matrix metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF).


RESULTS
Twenty-four patients were diagnosed as having TZ cancer and the remaining 100 as having PZ cancer. Prostate specific antigen (PSA) values in patients with TZ cancer were significantly higher than in those with PZ cancer. Tumour volume in TZ cancer was significantly greater than that in PZ cancer, but there was no significant difference in biochemical recurrence-free survival between the groups. Immunohistochemistry showed that despite there being no differences in Bcl-2 and VEGF expression between TZ and PZ cancers, there was significantly greater expression of Ki-67, MMP-2 and MMP-9 in PZ than TZ cancers.


CONCLUSIONS
Despite there being no significant difference in biochemical recurrence-free survival after RP between patients with TZ and PZ cancers, there was less cell proliferation and biomarker levels related to invasive potential in TZ than in PZ cancers.
Sakai
Iori
I
Department of Urology, Hyogo Medical Center for Adults, Akashi, Japan.
Harada
Ken-Ichi
K
Hara
Isao
I
Eto
Hiroshi
H
Miyake
Hideaki
H
D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis / Q000097:blood; D016009:Chi-Square Distribution; D018572:Disease-Free Survival; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000032:analysis; D020780:Matrix Metalloproteinase 9 / Q000032:analysis; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D018709:Statistics, Nonparametric; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis
D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D019253:Proto-Oncogene Proteins c-bcl-2; D042461:Vascular Endothelial Growth Factor A; D017430:Prostate-Specific Antigen; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9