Nathalie Nicolaiew

Prostate Cancer Antigen 3 Score Accurately Predicts Tumour Volume and Might Help in Selecting Prostate Cancer Patients for Active Surveillance

BACKGROUND The optimal selection of prostate cancer (PCa) patients for active surveillance (AS) is currently being debated. OBJECTIVE To assess the impact of urinary prostate cancer antigen 3 (PCA3) score as an AS criterion instead of and in addition to the current criteria. DESIGN, SETTING, AND PARTICIPANTS We prospectively studied 106 consecutive low-risk PCa patients (prostate-specific antigen [PSA] ≤10 ng/ml, clinical stage T1c-T2a, and biopsy Gleason score 6) who underwent a PCA3 urine test before radical prostatectomy (RP). MEASUREMENTS Performance of AS criteria (biopsy criteria, PCA3 score, PSA density, and magnetic resonance imaging [MRI] findings) was tested in predicting four prognostic pathologic findings in RP specimens: (1) pT3-4 disease; (2) overall unfavourable disease (OUD) defined by pT3-4 disease and/or pathologic primary Gleason pattern 4; (3) tumour volume <0.5 cm(3); and (4) insignificant PCa. RESULTS AND LIMITATIONS The PCA3 score was strongly correlated with the tumour volume in a linear regression analysis (p<0.001, r=0.409). The risk of having a cancer ≥0.5 cm(3) and a significant PCa was increased three-fold in men with a PCA3 score of ≥25 compared with men with a PCA3 score of <25 with most AS biopsy criteria used. There was a trend towards higher PCA3 scores in patients with unfavourable and non-organ-confined disease and Gleason >6 cancers. In a multivariate analysis taking into account each AS criterion, a high PCA3 score (≥25) was an important predictive factor for tumour volume ≥0.5 cm(3) (odds ratio [OR]: 5.4; p=0.010) and significant PCa (OR: 12.7; p=0.003). Biopsy criteria and MRI findings were significantly associated with OUD (OR: 3.9 and 5.0, respectively; p=0.030 and p=0.025, respectively). CONCLUSIONS PCA3 score may be a useful marker to improve the selection for AS in addition to the current AS criteria. With a predictive cut-off of 25, PCA3 score is strongly indicative for tumour volume and insignificant PCa.

Prostate Cancer Detection Rate in Patients with Repeated Extended 21-Sample Needle Biopsy

BACKGROUND Prevalence of prostate cancer (PCa) after a negative first extended prostate needle biopsy protocol is unknown. OBJECTIVE To evaluate the prevalence of significant PCa in patients who have had a negative first extended prostate biopsy protocol. DESIGN, SETTING, AND PARTICIPANTS Between March 2001 and May 2007, 2500 consecutive patients underwent an extended protocol of 21 biopsies. Of 953 patients who had a negative first extended prostate biopsy procedure, 231 patients underwent a second or more set of 21-core biopsies. Indications for repeated biopsies were persistently elevated prostate-specific antigen (PSA), PSA increase during the follow-up, or prior prostatic intraepithelial neoplasia (PIN), or atypical small acinar proliferation (ASAP). INTERVENTION All participants underwent at least two extended prostate needle biopsy protocols. MEASUREMENTS Clinical and pathologic factors (age, PSA, PSA doubling time, PIN, ASAP, digital rectal exam [DRE]) were analyzed for their ability to predict positive biopsy, and tumour parameters were assessed in patients undergoing radical prostatectomy. RESULTS AND LIMITATIONS Second, third, and fourth extended 21-sample biopsy procedures yielded a diagnosis of PCa in 18%, 17%, and 14% of patients respectively. Patients with prior PIN had 16% risk of prostate cancer; patients with ASAP had a 42% risk. The mean number of positive cores was 2.19. Prostate volume and PSA density were statistically significant predictors of positive biopsy (p<0.05). For the 43 patients who underwent radical prostatectomy, pathologic findings revealed mean Gleason score of 6.7 (6-8), pT2a-c in 72%, pT3a in16%, and pT4 in 7%. Mean cancer volume was 1.15 cc and 85.2% of tumours were clinically significant (tumour volume > 0.5 cc, Gleason > or = 7 and/or pT3). CONCLUSIONS Negative first extended biopsies should not reassure a patient of not having PCa. However, prostate cancers detected after two or more sets of extended procedures, appear to be localized (intracapsular disease) and well-differentiated prostate cancers, although they are still clinically significant.

Combination of Polymorphisms From Genes Related to Estrogen Metabolism and Risk of Prostate Cancers: The Hidden Face of Estrogens

PURPOSE The association between common functional polymorphisms from the CYP17, CYP19, CYP1B1, and COMT genes involved in the estrogen metabolism and the risk of prostate carcinoma was evaluated. PATIENTS AND METHODS The study investigated 1,983 white French men (1,101 patients with prostate cancer and 882 healthy controls) aged between 40 and 98 years. The different alleles and genotypes were analyzed according to case-control status, aggressiveness pattern of the tumors, age at onset, and family history of cancers. RESULTS The VV (high activity) genotype of the V432L polymorphism from CYP1B1 (odds ratio [OR] = 1.36; 95% CI, 1.03 to 1.79; P = .031), and the long allele (> 175 bp) of the TTTA repeat from CYP19 (OR, 1.26; 95% CI, 1.08 to 1.47; P = .003) were significantly associated with the risk of prostate cancer. An additive effect was observed when we combined the two at-risk alleles (OR = 1.63; 95% CI, 1.24 to 2.13; P < .001). The association was stronger for the CYP1B1 VV genotype (OR = 1.55; 95% CI, 1.13 to 2.13; P = .007) among the group of patients with highly aggressive disease. Stratification by age at onset showed that the associations of CYP1B1 and CYP19 variants were largely confined to the younger prostate cancer patients. CONCLUSION This association between polymorphisms from genes related to estrogen metabolism and prostate cancer risk suggest new clinical considerations in the management of prostate cancer: the development of new prevention trials based on genetic profiling and the evaluation of specific inhibitors involving the estrogen pathways.

Class III beta-tubulin expression predicts prostate tumor aggressiveness and patient response to docetaxel-based chemotherapy.

Expression of class III β-tubulin (βIII-tubulin) correlates with tumor progression and resistance to taxane-based therapies for several human malignancies, but its use as a biomarker of tumor behavior in prostate cancer (PCa) remains largely unexplored. Here, we describe βIII-tubulin immunohistochemical staining patterns of prostate tumors obtained from a broad spectrum of PCa patients, some of whom subsequently received docetaxel therapy for castration-resistant PCa (CRPC). Elevated βIII-tubulin expression was significantly associated with tumor aggressiveness in PCa patients with presumed localized disease, as it was found to be an independent marker of biochemical recurrence after treatment. Additionally, βIII-tubulin expression in tumor cells was an independent predictor of lower overall survival for patients receiving docetaxel-based chemotherapy for CRPC. Manipulation of βIII-tubulin expression in human PCa cell lines using a human βIII-tubulin expression vector or βIII-tubulin small interfering RNA altered cell survival in response to docetaxel treatment in a manner that supports a role for βIII-tubulin expression as a mediator of PCa cell resistance to docetaxel therapy. Our findings suggest a role for βIII-tubulin as candidate theranostic biomarker to predict the response to docetaxel-based chemotherapy as well as to target for treatment of docetaxel-resistant CRPC.

Risk of repeat biopsy and prostate cancer detection after an initial extended negative biopsy: longitudinal follow‐up from a prospective trial

Even after a negative set of prostate biopsies, the risk of undetected prostate cancer remains clinically significant. Predictive markers of such a risk are undefined. In addition to PSA and PSAD, low prostate volume and %fPSA are interesting time‐varying risk factors and are relevant in biopsy decision‐making.

Association between estrogen and androgen receptor genes and prostate cancer risk

OBJECTIVE Prostate cancer (PC) is one of the principal causes of death among men. Steroid hormones are involved in normal prostate growth and carcinogenesis. The purpose of our study was to investigate the effects on PC risk of polymorphisms from three steroid hormone receptor genes: the androgen (AR), and the alpha (ESR1) and beta (ESR2) estrogen receptors. DESIGN AND METHODS The study was performed on a Caucasian population of 1045 PC patients and 814 controls. Using a logistic regression model, the different alleles and genotypes from those polymorphisms were analyzed according to case/control status, the tumor aggressiveness, and the age at onset. RESULTS A significant association between PC risk and the pooled 4/5, 5/6, and 6/6 genotypes of the GGGA repeat located in the first intron of ESR1 (odds ratio (OR)=3.00, 95% CI=1.32-6.82, P=0.008) was observed. When we stratified the cases, this association was confined to patients with a Gleason score of 2-4 (OR=8.34, 95% CI=2.91-23.91, P<0.0001) or late onset PC (OR=2.91, 95% CI=1.22-6.93, P=0.016). An association between a short AR CAG repeat (less than 17 repeats) was also observed among patients with late onset PC (OR=2.34, 95% CI=1.15-4.76, P=0.019). CONCLUSIONS These findings suggest that the GGGA repeat from ESR1 and the CAG repeat from AR may be associated with risk of late onset PC.

Prediction of the Risk of Harboring Prostate Cancer by a Prebiopsy Nomogram Based on Extended Biopsy Protocol

Objective: We aimed to build a nomogram allowing to predict the probability of prostate cancer (PC) after an initial 21-core biopsy and with readily available clinical data. Methods: 1,490 screened men who underwent an initial 21-core biopsy protocol were included. A multivariate logistic regression was realized including age, prostate volume, prostate-specific antigen (PSA) level, digital rectal examination (DRE) and transrectal ultrasonography (TRUS). Receiver-operating characteristic estimates were used to quantify accuracy of each model. Results: PC was detected in 41.3% of the patients. Median PSA, age and prostate volume were 6.2 ng/ml (range 0.2-50), 64.6 years (range 33-87) and 40 ml (range 10-270), respectively. Abnormal TRUS findings were detected in 14.7% of patients. Age, PSA level, prostate volume, DRE and TRUS were significantly associated with PC (all p ≤ 0.004) in univariable logistic regression analysis. In multivariate logistic regression analysis, significant associations were found for age, PSA level, prostate volume and DRE. Predictive accuracy estimate of this model was equal to 0.70. TRUS was not an independent predictor of PC. Conclusions: We constructed the first prebiopsy predictive nomogram based on an extended 21-core biopsy procedure with age, PSA level, DRE and prostate volume which are readily available clinical data to urologists.

Abstract 5472: Class III beta-tubulin in castration resistant human prostate cancer

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC BACKGROUND: Class III β-tubulin (βIII-tubulin) is expressed in tissues of neuronal lineage but it is also expressed in several human malignancies including non small cell lung carcinoma, breast and ovarian cancer. Overexpression of βIII-tubulin in these tumors is associated with an unfavorable outcome and resistance to taxane-based therapies. βIII-tubulin deregulation however is still poorly documented in prostate cancer. Previously, we reported that βIII-tubulin expression is increased in prostate cancer (PCa) cells by androgen ablation. Here we sought to better characterize the contribution of βIII-tubulin to castration resistant PCa, the stage of the tumor most responsible for mortality from PCa. METHODS: βIII-tubulin expression was assayed by immunohistochemistry in prostate tumors obtained from patients with castration resistant PCa. Protein expression was scored as null (0), weak (1), moderate (2) and strong (3) and considered significant when the score was 2 or more in more than 10% of cancer cells. Consecutive sections were also immunostained for neuroendocrine biomarkers, neuron specific enolase (NSE) and chromogranin A (CgA). An androgen independent (AI) variant of LNCaP cells (AI-LNCaP) was assessed for the effects of docetaxel treatment on βIII-tubulin expression. Finally, DU145 cells stably overexpressing βIII-tubulin were tested for their sensitivity to docetaxel relative to control vector-transfected cells. RESULTS: 24/40 specimens of castration resistant tumors were found to express significant levels of βIII-tubulin. In 6 out of 22 cases analyzed, regions of the tumor positively co-stained for both βIII tubulin and NSE, however none of 8 evaluated cases showed co-staining for βIII-tubulin and CgA. AI-LNCaP cells treated with 5 to 10 nM docetaxel showed a time dependent increase in βIII-tubulin expression. DU145 cells stably overexpressing βIII-tubulin were found to be more resistant to docetaxel than the parental counterpart with a 2-fold increase in the IC50. CONCLUSION: Our data indicate that βIII-tubulin is expressed in the majority of castration resistant prostate tumors. Although βIII-tubulin immunostaining of prostate tumor cells sometimes coincides with staining for neuroendocrine markers, most βIII-tubulin positive tumor cells examined did not show coincidental staining so increased βIII-tubulin expression may occur independently of NE differentiation. Regardless, our in vitro studies support a role for βIII-tubulin in the emergence of doxetaxel resistance by androgen independent human PCa cells. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5472.