Overall and worst gleason scores are equally good predictors of prostate cancer progression.

BACKGROUND: Gleason scoring has experienced several modifications during the past decade. So far, only one study has compared the prognostic abilities of worst (WGS) and overall (OGS) modified Gleason scores after the ISUP 2005 conference. Prostatic needle biopsies are individually paraffin-embedded in 57% of European pathology laboratories, whereas the rest of laboratories embed multiple (2 - 6) biopsies per one paraffin-block. Differences in the processing method can have a far-reaching effect, because reporting of the Gleason score (GS) is different for individually embedded and pooled biopsies, and GS is one of the most important factors when selecting treatment for patients. METHODS: The study material consisted of needle biopsies from 236 prostate cancer patients that were endocrine-treated in 1999-2003. Biopsies from left side and right side were embedded separately. Haematoxylin-eosin-stained slides were scanned and analyzed on web-based virtual microscopy. Worst and overall Gleason scores were assessed according to the modified Gleason score schema after analyzing each biopsy separately. The compound Gleason scores (CGS) were obtained from the original pathology reports. Two different grade groupings were used: GS 6 or less vs. 7 vs. 8 or above; and GS 7(3 + 4) or less vs. 7(4 + 3) and 8 vs. 9-10. The prognostic ability of the three scoring methods to predict biochemical progression was compared with Kaplan-Meier survival analysis and univariate and multivariate Cox regression analyses. RESULTS: The median follow-up time of the patients was 64.5 months (range 0-118). The modified GS criteria led to upgrading of the Gleason sums compared to the original CGS from the pathology reports 1999-2003 (mean 7.0 for CGS, 7.5 for OGS, 7.6 for WGS). In 43 cases WGS was > OGS. In a univariate analysis the relative risks were 2.1 (95%-confidence interval 1.8-2.4) for CGS, 2.5 (2.1-2.8) for OGS, and 2.6 (2.2-2.9) for WGS. In a multivariate analysis, OGS was the only independent prognostic factor. CONCLUSIONS: All of the three Gleason scoring methods are strong predictors of biochemical recurrence. The use of modified Gleason scoring leads to upgrading of GS, but also improves the prognostic value of the scoring. No significant prognostic differences between OGS and WGS could be shown, which may relate to the apparent narrowing of the GS scale from 2-10 to 5-10 due to the recent modifications.

Histopathological variables and biomarkers enhancer of zeste homologue 2, Ki-67 and minichromosome maintenance protein 7 as prognosticators in primarily endocrine-treated prostate cancer.

OBJECTIVE: • To evaluate the prognostic value of histopathological variables and immunostainings of biomarkers enhancer of zeste homologue 2 (EZH2), Ki-67 and minichromosome maintenance protein 7 (MCM7) from core biopsies of hormonally treated patients with prostate cancer. PATIENTS AND METHODS: • Biopsies of 247 primarily endocrine-treated patients were analysed for histopathological characteristics and Gleason scores (GS) according to the revised guidelines of International Society of Urologic Pathology (ISUP) consensus conference 2005. • Immunohistochemical stainings were analysed with the aid of digital image analysis. • The prognostic value of the histopathological variables and the biomarkers was analysed with univariate and multivariate Cox regression analysis, with biochemical recurrence as an endpoint. RESULTS: • Biomarkers EZH2 (relative risk [RR] 2.0, 95% confidence interval 1.2-3.3), Ki-67 (3.4, 2.1-5.5) and MCM7 (2.4, 1.5-3.9) were significantly associated with progression-free survival in a univariate analysis. • Ki-67 immunostaining index detected high-risk patients with GS of 7 (9.1, 8.0-10.3). • In a multivariate analysis with non-conventional GS groups 5-7 (3 + 4), 7(4 + 3)-8, and 9-10, the independent prognostic markers were pretreatment GS (2.2, 1.5-3.2), prostate-specific antigen (PSA) level (2.1, 1.1-4.2), perineural invasion (PNI) (1.6, 1.2-2.2), and clinical T-stage (cT) (1.9, 1.0-3.7). • Combination of the independent markers (PSA level > 20 ng/mL or GS >3 + 4 or PNI >3 or cT >2) yielded best risk stratification (RR 11.6, 10.4-12.7). CONCLUSIONS: • GS remains one of the most important prognostic factors in prostate cancer. However, the refined guidelines by ISUP 2005 might have shifted the threshold between low-grade and high-grade cancers from GS 6 vs 7 to GS 3 + 4 vs 4 + 3. • PNI is an independent prognostic marker superior to cT. • Ki-67 is the most useful biomarker in detecting patients with GS = 7 at high risk for progression.

Expression of ERalpha and ERbeta in prostate cancer.

BACKGROUND: It has been suggested that estrogens and their receptors (ERs) may be involved in the development and progression of prostate cancer. To elucidate the significance of these receptors, expression of both ERalpha and ERbeta was measured in benign and malignant prostate tumors, as well as in cell lines. METHODS: Expression of ERalpha and ERbeta was measured in prostate hyperplasia (BPH, n = 7), androgen-dependent (n = 30) as well as hormone-refractory (n = 12) prostate carcinomas, and in four prostate cancer cell lines (LNCaP, DU145, PC-3, and 22Rv1) using real-time quantitative RT-PCR. RESULTS: Only low-level expression of ERalpha was found in all tumor types and cell lines. The level of expression was similar to that observed in breast carcinomas found to be negative for ERalpha by immunohistochemistry. All cell lines showed low, but detectable, levels of ERbeta expression. The mean expression of ERbeta in the hormone-refractory carcinomas was about half that seen in BPH or the androgen-dependent carcinomas; however, the difference was not statistically significant. CONCLUSIONS: The data suggest it is unlikely that alterations in the expression of either ER are commonly involved in the progression of prostate cancer.

Expression and gene copy number analysis of ERBB2 oncogene in prostate cancer.

An anti-ERBB2 antibody, trastuzumab, has been shown to be highly efficient in the treatment of metastatic breast cancers overexpressing the ERBB2 gene. It has been suggested that overexpression and even amplification of ERBB2 may play a role in the development of prostate cancer. Here, we have analyzed gene copy number and expression of the ERBB2 gene in both androgen-dependent primary and metastatic tumors, as well as recurrent hormone-refractory tumors. The expression levels were compared to the expression of ERBB2 in breast cancers with or without ERBB2 gene amplification. Of 126 prostate tumors, chromogenic in situ hybridization (CISH) revealed only 1 case containing borderline (six to eight copies) amplifications of ERBB2. This hormone-refractory tumor, however, did not express ERBB2 protein. Immunohistochemical staining of ERBB2 protein was negative (0 or 1+ intensity) in all prostate samples (n = 124) analyzed. To quantitate the level of ERBB2 mRNA expression in prostate tumors (n = 34) and cell lines (n = 3), as well as in breast tumors (n = 30) and cell lines (n = 16), real-time reverse transcriptase-polymerase chain reaction (LightCycler) methodology was used. The expression level was similar in all prostate tumor types and corresponded to the level of expression in breast carcinomas without ERBB2 amplification. Breast tumors with ERBB2 amplification expressed, on average, approximately 20 times (P < 0.001) higher mRNA levels than prostate tumors or breast carcinomas without the gene amplification. In conclusion, the expression of ERBB2 in prostate cancer is relatively low, and is not altered during disease progression. Thus, it is unlikely that treatment modalities relying on the overexpression of ERBB2 gene will be useful in treating prostate cancer.