A prognostic index model for predicting overall survival in patients with metastatic castration-resistant prostate cancer treated with abiraterone acetate after docetaxel.

BACKGROUND: Few prognostic models for overall survival (OS) are available for patients with metastatic castration-resistant prostate cancer (mCRPC) treated with recently approved agents. We developed a prognostic index model using readily available clinical and laboratory factors from a phase III trial of abiraterone acetate (hereafter abiraterone) in combination with prednisone in post-docetaxel mCRPC. PATIENTS AND METHODS: Baseline data were available from 762 patients treated with abiraterone-prednisone. Factors were assessed for association with OS through a univariate Cox model and used in a multivariate Cox model with a stepwise procedure to identify those of significance. Data were validated using an independent, external, population-based cohort. RESULTS: Six risk factors individually associated with poor prognosis were included in the final model: lactate dehydrogenase > upper limit of normal (ULN) [hazard ratio (HR) = 2.31], Eastern Cooperative Oncology Group performance status of 2 (HR = 2.19), presence of liver metastases (HR = 2.00), albumin ≤4 g/dl (HR = 1.54), alkaline phosphatase > ULN (HR = 1.38) and time from start of initial androgen-deprivation therapy to start of treatment ≤36 months (HR = 1.30). Patients were categorized into good (n = 369, 46%), intermediate (n = 321, 40%) and poor (n = 107, 13%) prognosis groups based on the number of risk factors and relative HRs. The C-index was 0.70 ± 0.014. The model was validated by the external dataset (n = 286). CONCLUSION: This analysis identified six factors used to model survival in mCRPC and categorized patients into three distinct risk groups. Prognostic stratification with this model could assist clinical practice decisions for follow-up and monitoring, and may aid in clinical trial design. TRIAL REGISTRATION NUMBERS: NCT00638690.

Imaging yield from 133 consecutive patients with prostate cancer and low trigger PSA from a single institution.

AIM: To investigate the yield of imaging in patients with relapsed prostate cancer (PC) with a low trigger prostate-specific antigen (PSA). MATERIALS AND METHODS: This institutional review board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant retrospective study included all 133 patients (mean age 68 years; range 45-88; median 69 months since original diagnosis; interquartile range [IQR]: 32-139) with hormone-sensitive PC (HSPC, n=28) or castration-resistant PC (CRPC, n=105) and trigger PSA <4 ng/ml, who underwent same-day bone scintigraphy and computed tomography (CT; total 224 time points) at Dana-Farber Cancer Institute from January to December 2013. Clinical and pathological data were obtained by manual review of the electronic medical records. All the included bone scintigraphs and CT images were reviewed by a fellowship-trained oncoradiologist to record the metastatic pattern and any clinically significant non-metastatic findings. RESULTS: Ninety-four of the 133 (71%) patients had metastatic disease (18/28 [64%] with HSPC, 76/105 [72%] with CRPC). Forty-one of the 133 (31%) patients developed new metastatic disease and 23/133 (17%) developed new clinically significant non-metastatic findings. The incidence of osseous, nodal, and visceral metastases, and clinically significant non-metastatic findings was similar across the HSPC and CRPC groups (p>0.05 for all). Fifty-seven of the 133 (43%) patients had findings seen only at CT, of which 37 had new extra-osseous findings. Only 2/133 (2%) had findings at bone scintigraphy not seen at CT, both in areas not covered on CT. CONCLUSION: Imaging frequently demonstrated new metastatic and non-metastatic findings in patients with a low trigger PSA. CT is valuable in these patients because extra-osseous findings not visible at bone scintigraphy are frequently seen.

Multicenter phase II study of trabectedin in patients with metastatic castration-resistant prostate cancer.

BACKGROUND: This multicenter phase II trial evaluated the efficacy and safety of trabectedin in metastatic castration-resistant prostate cancer (CRPC). PATIENTS AND METHODS: Two schedules were evaluated in three cohorts: weekly as 3-h i.v. infusion at 0.58 mg/m(2) for 3 out of 4 weeks (Cohort A, n = 33), and every 3 weeks (q3wk) as 24-h infusion at 1.5 mg/m(2) (Cohort B1, n = 5) and 1.2 mg/m(2) (Cohort B2, n = 20). The primary end point was prostate-specific antigen (PSA) response; secondary end points included safety, tolerability and time to progression (TTP). RESULTS: Trabectedin resulted in PSA declines ≥ 50% in 12.5% (Cohort A) and 10.5% (Cohort B2) of patients. Among men pretreated with taxane-based chemotherapy, PSA response was 13.6% (Cohort A) and 15.4% (Cohort B2). PSA responses lasted 4.1-8.6 months, and median TTP was 1.5 months (Cohort A) and 1.9 months (Cohort B2). The dose of 1.5 mg/m(2) (approved for soft tissue sarcoma) given as 24-h infusion q3wk was not tolerable in these patients. At 1.2 mg/m(2) q3wk and 0.58 mg/m(2) weekly, the most common adverse events were nausea, fatigue and transient neutropenia and transaminase increase. CONCLUSIONS: Two different trabectedin schedules showed modest activity in metastatic CRPC. Further studies may require identification of predictive factors of response in prostate cancer.

Expression of human adenosine deaminase in nonhuman primates after retrovirus-mediated gene transfer.

Primate bone marrow cells were infected with a retroviral vector carrying the genes for human adenosine deaminase (h-ADA) and bacterial neomycin resistance (neor). The infected cells were infused back into the lethally irradiated donor animals. Several monkeys fully reconstituted and were shown to express the h-ADA and neor genes at low levels in their recirculating hematopoietic cells for short periods of time.

Phase II study of sunitinib in men with advanced prostate cancer.

BACKGROUND: This study explored the efficacy and tolerability of sunitinib, an inhibitor of tyrosine kinase receptors, in men with castration-resistant prostate cancer (CRPC). METHODS: Men with no prior chemotherapy (group A) and men with docetaxel (Taxotere)-resistant prostate cancer (group B) were treated with sunitinib. The primary end point was confirmed 50% prostate-specific antigen (PSA) decline. Secondary end points included objective response rate and safety. Serum-soluble biomarkers were measured. RESULTS: Seventeen men were enrolled in each group. One confirmed PSA response was observed in each group, and an additional eight men and seven men had stable PSA at week 12 in groups A and B, respectively. Improvements in imaging were observed in the absence of post-treatment PSA declines. Common adverse effects included fatigue, nausea, diarrhea, myelosuppression and transaminase elevation. Significant changes following sunitinib treatment were observed in serum-soluble biomarkers including soluble vascular endothelial growth factor receptor-2, platelet-derived growth factor aa, placental growth factor and leptin. CONCLUSIONS: Sunitinib monotherapy resulted in few confirmed 50% post-treatment declines in PSA in men with CRPC. Serum markers of angiogenesis confirmed on-target effects of sunitinib. Assessments of radiographic disease status were often discordant with changes in PSA, indicating that alternate end points are important in future trials.

High-level recombinant gene expression in rabbit endothelial cells transduced by retroviral vectors.

By virtue of its immediate contact with the circulating blood, the endothelium provides an attractive target for retroviral vector transduction for the purpose of gene therapy. To see whether efficient gene transfer and expression was feasible, rabbit aortic endothelial cells were infected with three Moloney murine leukemia virus-derived retroviral vectors. Two of these vectors carry genes encoding products that are not secreted: N2, containing only the selectable marker gene neoR, and SAX, containing both neoR gene and an SV40-promoted adenosine deaminase (ADA) gene. The third vector, G2N, contains a secretory rat growth hormone (rGH) gene and an SV40-promoted neoR gene. Infection with all three vectors resulted in expression of the respective genes. A high level of human ADA expression was observed in infected endothelial cell populations both before and after selection in G418. G2N-infected rabbit aortic endothelial cells that were grown on a synthetic vascular graft continued to secrete rGH into the culture medium. These studies suggest that endothelial cells may serve as vehicles for the introduction in vivo of functioning recombinant genes.

TMPRSS2:ERG gene fusion associated with lethal prostate cancer in a watchful waiting cohort.

The identification of the TMPRSS2:ERG fusion in prostate cancer suggests that distinct molecular subtypes may define risk for disease progression. In surgical series, TMPRSS2:ERG fusion was identified in 50% of the tumors. Here, we report on a population-based cohort of men with localized prostate cancers followed by expectant (watchful waiting) therapy with 15% (17/111) TMPRSS2:ERG fusion. We identified a statistically significant association between TMPRSS2:ERG fusion and prostate cancer specific death (cumulative incidence ratio=2.7, P<0.01, 95% confidence interval=1.3-5.8). Quantitative reverse-transcription-polymerase chain reaction demonstrated high ets-related [corrected] gene (ERG) expression to be associated with TMPRSS2:ERG fusion (P<0.005). These data suggest that TMPRSS2:ERG fusion prostate cancers may have a more aggressive phenotype, possibly mediated through increased ERG expression.

Duration of the anti-androgen in men undergoing 6 months of an LHRH agonist and radiation therapy for unfavorable-risk prostate cancer and the risk of death.

BACKGROUND: Whether adding a first-generation anti-androgen (AA) to a luteinizing hormone-releasing hormone agonist in the radiotherapeutic management of unfavorable-risk prostate cancer (PC) reduces the risk of all-cause and PC-specific mortality (ACM and PCSM) among men within differing comorbidity subgroups is unknown. METHODS: Between 1995 and 2001, 206 men with unfavorable-risk PC were enrolled in a randomized trial comparing radiation with or without 6 months of androgen-deprivation therapy (ADT). Partial AA use (median: 4.2 months) occurred in 29 of the 102 men randomized to ADT. Cox, and Fine and Gray's regressions were used to evaluate the impact of full versus partial AA use on PCSM and ACM-risk within comorbidity subgroups. RESULTS: After a median follow-up of 16.62 years, 156 men died. In men with moderate to severe comorbidity increasing death was observed as treatment transitioned from no to partial to full ADT (P=0.02) with an increased ACM-risk with full versus partial AA use (adjusted hazard ratio (AHR), 2.25 (95% confidence interval (CI), 0.94-5.41); P=0.07); whereas only 1 and no PC deaths occurred in men receiving a partial versus full AA course, respectively. Among men with no or minimal comorbidity there was no decrease in ACM (AHR, 0.97 (95% CI, 0.49-1.91); P=0.92) or PCSM-risk (AHR 0.39 (95% CI 0.07-52.18); P=0.28) in comparing full versus partial AA use. CONCLUSION: Increasing AA use by 2 months does not appear to impact survival in men with localized unfavorable-risk PC and no or minimal comorbidity, but may shorten survival in men with moderate to severe comorbidity, raising concern regarding in whom and for how long the AA should be prescribed.

The impact of comorbidity and PSA doubling time on the risk of death in men experiencing PSA failure following radiation therapy with or with androgen deprivation therapy for unfavorable-risk prostate cancer.

BACKGROUND: The optimal management of men with PSA failure following initial prostate cancer (PC) therapy stratified by comorbidity is unknown. We investigated the impact that PSA doubling time (DT) and comorbidity had on the risk of all-cause mortality (ACM), prostate cancer-specific mortality (PCSM) and other-cause mortality (OCM) following PSA failure. METHODS: Between 1995 and 2001, 206 men with unfavorable-risk PC were randomized to receive radiation therapy alone or in combination with 6 months of androgen deprivation therapy (ADT); 108 men experienced PSA failure and formed the study cohort. Cox and Fine-Gray regression analysis was used to determine whether PSA DT was associated with the risk of ACM and PCSM/OCM, respectively, stratified by comorbidity status using a validated metric. RESULTS: After a median follow-up of 13.71 years following PSA failure, 81 of the 108 men (75%) died. Longer PSA DT was associated with a decreased risk of PCSM in men with no/minimal (adjusted hazard ratio (AHR) 0.33, 95% confidence interval (CI) 0.17-0.65, P=0.001) and moderate/severe comorbidity (AHR 0.014, 95% CI 0.002-0.129, P=0.0002). However, because of the different contributions of the risk of OCM to risk of ACM within comorbidity subgroups, increasing PSA DT was only associated with a decreased risk of ACM in men with no/minimal (AHR 0.69, 95% CI 0.50-0.96, P=0.03) but not moderate/severe comorbidity (AHR 0.95, 95% CI 0.51-1.78, P=0.87). CONCLUSIONS: Both the extent of comorbidity and the PSA DT should be taken into consideration when deciding on appropriate management and/or clinical trial eligibility at the time of PSA failure.

Racial variation in prostate cancer incidence and in hormonal system markers among male health professionals.

BACKGROUND: Racial variation in prostate cancer incidence in the United States is pronounced, with African-American men having the highest rates. Whether differences in the distribution of known or suspected risk factors among racial groups explain this variation is unknown. METHODS: We evaluated prospectively the relation between prostate cancer and race among 45 410 U.S. male health professionals aged 40--75 years in 1986. We used multivariable, pooled logistic regression to adjust the rate ratio (RR) for potential dietary and lifestyle risk factors. We also measured circulating levels of steroid hormones, sex hormone-binding globulin, and vitamin D metabolites and length of the androgen receptor gene CAG repeat in a sample of African-American (n = 43), Asian (n = 52), and white (n = 55) participants and assessed variation by race in these possible prostate epithelial cell growth mediators by use of analysis of variance. Statistical tests were two-sided. RESULTS: The age-adjusted RR for prostate cancer was 1.73 (95% confidence interval [CI] = 1.23--2.45) for African-American men compared with white men. After multivariate adjustment, the RR increased to 1.81 (95% CI = 1.27--2.58). The rate of prostate cancer did not differ between Asians and whites. Steroid hormone and 1,25-dihydroxyvitamin D levels did not vary appreciably by race. However, the mean number of androgen receptor gene CAG repeats was lower among African-Americans (mean +/- standard deviation = 20.1 +/- 3.5) than among whites (22.1 +/- 3.1; P =.007) and Asians (22.1 +/- 3.9; P =.009). CONCLUSIONS: Our results confirm the elevated incidence of prostate cancer among African Americans and show that it is not explained by differences in the distribution of possible dietary and lifestyle risk factors in this cohort. Racial variation in length of the androgen receptor gene CAG repeat may explain a small part of the excess risk of prostate cancer among African-American men in this cohort.

Expression of a human complementary DNA for the multidrug resistance gene in murine hematopoietic precursor cells with the use of retroviral gene transfer.

In multidrug resistance, cells become simultaneously resistant to anthracyclines, vinca alkaloids, epipodophyllotoxins, and certain other natural product cytotoxic drugs. Resistance results from synthesis of a multidrug transporter (P-glycoprotein) encoded by the MDR1 gene (also known as the PGY1 gene). In the present study, a retrovirus vector containing a complementary DNA for the human multidrug resistance gene HaMDR1/A was used to transfer the multidrug resistance phenotype to bone marrow cells of the DBA/2J mouse. A high proportion of transduced bone marrow cells showed resistance to both colchicine and vinblastine, as determined by in vitro colony formation of hematopoietic precursor cells. In addition, brief culturing of the cells in a cytotoxic drug following exposure to the retrovirus vector could be used to increase the proportion of bone marrow cell colonies that were resistant. These results may serve as a model for the generation and selection of bone marrow cells resistant to the toxic effects of chemotherapeutic agents in vivo.

Patient-reported impotence and incontinence after nerve-sparing radical prostatectomy.

BACKGROUND: The age-adjusted rate of radical prostatectomy, the most common treatment of early (nonmetastatic) prostate cancer, increased almost sixfold between 1984 and 1990. This increase was due in part to reported improvements in postoperative sexual potency after the use of newly developed "nerve-sparing" procedures. However, published estimates from physicians of impotence following various types of radical prostatectomy may be low, since not all patients may report treatment-related complications accurately and completely to their doctors. In contrast, direct surveys of patients indicate much higher rates of postoperative sexual and urinary dysfunction. One problem with most physician and patient surveys is that they have been performed retrospectively, and pretreatment impotence and incontinence prevalent in older men cannot be assessed accurately in retrospective studies. PURPOSE: This study was initiated in a cohort of men before they underwent radical prostatectomy to assess treatment-related effects on impotence and incontinence. METHODS: The study population consisted of 94 men enrolled in a cohort study of treatment for early prostate cancer. The patients completed questionnaires about sexual and urinary functions before surgery and at 3 and 12 months after surgery and had adequate information to assess the type of surgical technique used (non-nerve-sparing, unilateral nerve-sparing, or bilateral nerve-sparing). Because items assessing sexual function were inadvertently omitted from the questionnaire in the initial months of the study, information on sexual function for all time periods was available for only 49 men. RESULTS: Compared with men who had not been treated with a nerve-sparing procedure, men who underwent nerve-sparing radical prostatectomy, particularly of the bilateral type, were younger and had better prognostic features, indicating less advanced cancers. Before surgery, nine (75%) of 12 men not treated with a nerve-sparing procedure reported erections that were usually inadequate for sexual intercourse compared with six (33%) of 18 men and one (5%) of 19 men who underwent unilateral and bilateral nerve-sparing prostatectomies, respectively. At 12 months after surgery, most men reported inadequate erections, including 15 (79%) of the 19 men who had bilateral nerve-sparing surgery; unilateral nerve preservation provided no apparent benefit. In general, nerve-sparing surgery was associated with more use of absorbent pads at 3 and 12 months following treatment, and this approach was associated with substantial urinary incontinence at 3 months but not at 12 months following surgery. CONCLUSIONS: Nerve-sparing prostatectomy, particularly when performed unilaterally, improves postoperative sexual function to a lesser extent than previously reported. Because men with preoperative impotence and more advanced cancers receive nerve-sparing surgery less often, some of the previously reported benefit of nerve preservation may be the result of patient selection and not of the technique per se.

Two differentially expressed genes in normal human prostate tissue and in carcinoma.

Alterations in transcriptional control may contribute directly to carcinogenesis. Using the differential display technique in prostate cancer cells compared to normal prostate epithelial cells, we identified a down-regulated gene and an up-regulated gene in cancer cells. The down-regulated gene encodes human epithelial tropomyosin (TMe1), a member of the family of actin filament-binding proteins. The up-regulated gene encodes cytochrome c oxidase subunit VIc (COSVIc), a protein of the respiration chain in the mitochondrial inner membrane. The differential display pattern was confirmed by Northern hybridization in both prostate tissue and cell lines. In situ hybridization of malignant prostate epithelial tissue using a digoxigenin-labeled antisense riboprobe detected strong staining for mRNA of COSVIc, as opposed to very weak staining in normal prostate epithelium. The expression pattern of COSVIc may be a useful marker for studying the alteration of energy metabolism in cancer cells and for the diagnosis of prostate cancer.

The V89L polymorphism in the 5alpha-reductase type 2 gene and risk of prostate cancer.

5alpha-Reductase type 2, the predominant prostatic isozyme of this protein, converts testosterone to dihydrotestosterone. It has been hypothesized that individuals with greater 5alpha-reductase activity are at increased risk for prostate cancer (CaP). A single nucleotide polymorphism of the 5alpha-reductase type 2 gene (SRD5A2) gives rise to a substitution of leucine (leu) for valine (val) at codon 89 (V89L), the presence of which may affect serum androstanediol glucuronide (AAG) levels. We studied the effect of this polymorphism on the risk of prostate cancer in a prospective, nested, case-control design within the Physicians' Health Study. In all controls (n = 799), the leu allele frequency was 0.30. Among the 386 controls with plasma AAG levels available, there was no significant association between AAG levels and V89L genotype. We also detected no significant association between risk for CaP and genotype [odds ratio: val/val = 1.0 (reference), leu/val = 0.96 (95% confidence interval, 0.76-1.20), and leu/ leu = 0.84 (95% confidence interval, 0.57-1.24)]. These data do not support a moderate to large effect of the SRD5A2 V89L polymorphism on plasma AAG levels or CaP risk in this predominantly Caucasian cohort, although a small effect cannot be completely excluded.

Modification of BRCA1- and BRCA2-associated breast cancer risk by AIB1 genotype and reproductive history.

Women who have inherited a germ-line mutation in the BRCA1 or BRCA2 (BRCA1/2) genes have a greatly increased risk of developing breast cancer compared with the general population. However, there is also substantial interindividual variability in the occurrence of breast cancer among BRCA1/2 mutation carriers. We hypothesize that genes involved in endocrine signaling may modify the BRCA1/2-associated age-specific breast cancer penetrance. We studied the effect of alleles at the AIB1 gene using a matched case-control sample of 448 women with germ-line BRCA1/2 mutations. We found that these women were at significantly higher breast cancer risk if they carried alleles with at least 28 or 29 polyglutamine repeats at AIB1, compared with women who carried alleles with fewer polyglutamine repeats [odds ratio (OR), 1.59; 95% confidence interval (CI), 1.03-2.47 and OR, 2.85; 95% CI, 1.64-4.96, respectively]. Late age at first live birth and nulliparity have been associated with increased breast cancer risk. We observed increases in BRCA1/2-associated breast cancer risk in women who were either nulliparous or had their first live birth after age 30 (OR, 3.06; 95% CI, 1.52-6.16). Women were at significantly increased risk if they were nulliparous or had a late age at first live birth and had AIB1 alleles no shorter than 28 or 29 or more AIB1 polyglutamine repeats (OR, 4.62; 95% CI, 2.02-10.56 and OR, 6.97; 95% CI, 1.71-28.43, respectively) than women with none of these risk factors. Our results support the hypothesis that pathways involving endocrine signaling, as measured through AIB1 genotype and reproductive history, may have a substantial effect on BRCA1/2-associated breast cancer risk.

Predictors of duration of abiraterone acetate in men with castration-resistant prostate cancer.

BACKGROUND: Androgen receptor signaling remains important in castration-resistant prostate cancer (CRPC) as demonstrated by the efficacy of abiraterone acetate (henceforth abiraterone) in phase III trials. Given that heterogeneous patient responses are observed, we sought to identify clinical factors associated with duration of abiraterone. METHODS: We retrospectively identified patients with CRPC treated with abiraterone in our database. Patient characteristics and types and duration of prostate cancer (PC) therapies were analyzed. These parameters were analyzed with duration of abiraterone in univariate and multivariable analyses. RESULTS: We identified 161 patients who had received abiraterone. All had received primary androgen-deprivation therapy (ADT), 86% prior secondary hormone therapy (SHT) and 33% prior chemotherapy. The median duration of primary ADT was 23 months, duration of SHT (excluding abiraterone) was 17 months and duration of chemotherapy was 8 months. We demonstrated that lower PSA at abiraterone initiation, longer primary ADT duration, no prior ketoconazole, no prior chemotherapy and longer chemotherapy duration were associated with a longer duration on abiraterone in univariate analysis. In multivariable analysis, duration of primary ADT (duration of abiraterone 9 versus 13 months for ⩽12 versus >12 months, P=0.03) and no use of prior chemotherapy (duration of abiraterone 16 versus 7 months for no versus yes prior chemotherapy, P<0.01) were associated with duration of abiraterone. CONCLUSIONS: Several clinical parameters, including type and duration of prior therapy, are predictive of responsiveness to abiraterone. These parameters are logical and correlate with smaller disease burden or less exposure to PC therapies. This information can help physicians counsel patients about the potential durability of efficacy of abiraterone. Identifying predictive biomarkers that inform patient selection for therapy is critical to optimizing treatment outcomes.

Is adjuvant chemotherapy necessary for patients with stage B1 testicular cancer?

Controversy exists concerning the role of adjunctive chemotherapy in patients with regional nodal involvement. A randomized study reported a 48% relapse rate for patients with positive nodes (stage B1 or stage B2), all of whom were salvaged by full-dose platinum-based chemotherapy. In a series of patients with positive nodes who received two cycles of adjunctive chemotherapy postoperatively, the relapse rate was only 2%. In order to evaluate the effect of retroperitoneal lymph node dissection on relapse rates in patients with stage B1 testicular cancer, a retrospective review of a series of 39 patients was performed. Criteria for inclusion included pathologic stage B1 (less than six positive nodes, located in the primary landing site, with no node greater than 2 cm in diameter and no extracapsular lymph node extension). Patients who fulfilled the criteria along with normalization of tumor markers were followed-up expectantly after retroperitoneal lymph node dissection. Thirty-nine patients were followed from 1 to 10 years with the median duration of follow-up of 3.5 years. Ten of the 39 patients had modified retroperitoneal lymph node dissections with preservation of antegrade ejaculation. The other 29 had full retroperitoneal lymph node dissections. Three relapses were seen, one patient with retrocrural and pulmonary metastases and two patients with pulmonary metastases only for a relapse rate of 8% (three of 39). Patients with stage B2 disease received adjunctive chemotherapy with two or three cycles of platinum-based chemotherapy. We conclude that retroperitoneal lymph node dissection alone is adequate treatment for the majority of patients with pathologic stage B1 testicular cancer. In that subset of patients, adjunctive chemotherapy should be reserved for relapse.

Treatment of locally advanced prostate cancer: is chemotherapy the next step?

PURPOSE: Management of locally advanced prostate cancer remains controversial. Various single and combination modality approaches have been advocated, but an accepted standard of care remains undefined. The purpose of this review is to define the current knowledge in managing locally advanced prostate cancer and to propose new treatment approaches based on current knowledge. MATERIALS AND METHODS: A MEDLINE search to detect all relevant articles on the management of locally advanced prostate cancer was performed. A review of the staging, natural history, and prognosis of this disease was also performed. RESULTS: The lack of a clearly defined treatment approach to patients with locally advanced prostate cancer stems from multiple factors, including ambiguities in clinical staging, inadequate knowledge of the natural history of the cancer, and a dearth of comparative randomized trials evaluating efficacy of different therapies. Single modality treatment, including radical prostatectomy (RP) or external-beam radiotherapy alone, is associated with high rates of failure. The use of adjuvant hormonal ablation therapy in combination with external-beam radiotherapy has shown improvement in progression-free and overall survival, although similar improvements have not been clearly demonstrated for surgical patients treated with hormonal therapy. New advances in chemotherapy for hormone-refractory prostate cancer suggest that response rates may be as high as 50% or more, and current trials are evaluating the addition of chemotherapy to hormonal ablation in either surgery or radiation therapy in locally advanced prostate cancer. CONCLUSION: Optimal management of locally advanced prostate cancer remains undefined. Standard treatment options include RP, external-beam radiotherapy, or hormonal ablation therapy, alone or in combination. New approaches being tested include improved methods for delivering radiation or combining hormonal ablation with surgery or radiation. It is possible that other forms of systemic therapy, including chemotherapy, may become important components of multimodality treatment. Clinical trials designed to test this hypothesis are ongoing.

Prognostic significance of reverse transcriptase polymerase chain reaction for prostate-specific antigen in men with hormone-refractory prostate cancer.

PURPOSE: To evaluate the prognostic significance of reverse transcriptase polymerase chain reaction (RT-PCR) detection of prostate-specific antigen (PSA) mRNA in the blood of men with hormone-refractory prostate cancer (HRPC). PATIENTS AND METHODS: Peripheral blood was obtained from 193 men enrolled on Cancer and Leukemia Group B Study 9480, a prospective randomized comparison of three doses of suramin. RNA was isolated from the samples and assayed for the presence of PSA transcripts by RT-PCR. RESULTS: RNA could be isolated in 156 (83%) of samples. PSA transcripts as measured by RT-PCR were detectable in 75 (48%) of the 156 patients. The median survival for those patients in whom no transcripts were detectable was 18 months (95% confidence interval [CI], 14 to 22 months) compared with 13 months (95% CI, 11 to 15 months) (P =.004) for those in whom transcripts were detectable. In a multivariate analysis in which other factors predictive of survival were used, RT-PCR for PSA provided independent prognostic information. CONCLUSION: RT-PCR for PSA predicts survival duration in a population of men with HRPC.

Detection of circulating tumor cells in men with localized prostate cancer.

PURPOSE: Using prostate-specific antigen (PSA) mRNA as a marker for prostatic epithelial cells, we have developed a sensitive technique that involves reverse transcription and polymerase chain reaction (RT-PCR) to detect circulating tumor cells in the peripheral blood of men with prostatic carcinoma (CaP). PATIENTS AND METHODS: A sensitive RT-PCR assay was used to evaluate the peripheral blood of 135 men with a history of CaP. Fourteen men with benign prostate disease, many of whom had elevated serum PSA levels, were used as a control group. RESULTS: All patients with benign prostate disease had a negative result in the RT-PCR assay. Of particular interest was a subgroup of 65 patients with clinically localized CaP evaluated before definitive local therapy. Five of these patients had detectable PSA mRNA by RT-PCR, suggesting circulating tumor cells. Within this group, systemic disease was detected by RT-PCR in some men with PSA levels less than 10 ng/mL and clinical stage B disease. Blood from men with hormone-refractory and progressive CaP demonstrated a higher frequency of PSA mRNA detectable by RT-PCR (10 of 20 patients). In contrast, none of seven patients with newly diagnosed metastatic prostate cancer and only one of seven patients with metastatic, hormone-responsive disease had blood that was positive for PSA mRNA by RT-PCR. CONCLUSION: Circulating tumor cells can be detected in the blood of a subset of patients with clinically localized CaP and a larger subset of patients with progressive metastatic disease.