Complications following surgery with or without radiotherapy or radiotherapy alone for prostate cancer.

BACKGROUND: Men undergoing treatment of clinically localised prostate cancer may experience a number of treatment-related complications, which affect their quality of life. METHODS: On the basis of population-based retrospective cohort of men undergoing surgery, with or without subsequent radiotherapy, or radiotherapy alone for prostate cancer in Ontario, Canada, we measured the incidence of treatment-related complications using administrative and billing data. RESULTS: Of 36 984 patients, 15 870 (42.9%) underwent surgery alone, 4519 (12.2%) underwent surgery followed by radiotherapy, and 16 595 (44.9%) underwent radiotherapy alone. For all end points except urologic procedures, the 5-year cumulative incidence rates were lowest in the surgery only group and highest in the radiotherapy only group. Intermediary rates were seen in the surgery followed by radiotherapy group, except for urologic procedures where rates were the highest in this group. Although age and comorbidity were important predictors, radiotherapy as the primary treatment modality was associated with higher rates for all complications (adjusted hazard ratios 1.6-4.7, P=0.002 to <0.0001). CONCLUSIONS: In patients treated for prostate cancer, radiation after surgery increases the rate of complications compared with surgery alone, though these rates remain lower than patients treated with radiation alone. This information may inform patient and physician decision making in the treatment of prostate cancer.

Patient selection for prostate focal therapy in the era of active surveillance: an International Delphi Consensus Project.

BACKGROUND: Whole-gland extirpation or irradiation is considered the gold standard for curative oncological treatment for localized prostate cancer, but is often associated with sexual and urinary impairment that adversely affects quality of life. This has led to increased interest in developing therapies with effective cancer control but less morbidity. We aimed to provide details of physician consensus on patient selection for prostate focal therapy (FT) in the era of contemporary prostate cancer management. METHODS: We undertook a four-stage Delphi consensus project among a panel of 47 international experts in prostate FT. Data on three main domains (role of biopsy/imaging, disease and patient factors) were collected in three iterative rounds of online questionnaires and feedback. Consensus was defined as agreement in ⩾80% of physicians. Finally, an in-person meeting was attended by a core group of 16 experts to review the data and formulate the consensus statement. RESULTS: Consensus was obtained in 16 of 18 subdomains. Multiparametric magnetic resonance imaging (mpMRI) is a standard imaging tool for patient selection for FT. In the presence of an mpMRI-suspicious lesion, histological confirmation is necessary prior to FT. In addition, systematic biopsy remains necessary to assess mpMRI-negative areas. However, adequate criteria for systematic biopsy remains indeterminate. FT can be recommended in D'Amico low-/intermediate-risk cancer including Gleason 4+3. Gleason 3+4 cancer, where localized, discrete and of favorable size represents the ideal case for FT. Tumor foci <1.5 ml on mpMRI or <20% of the prostate are suitable for FT, or up to 3 ml or 25% if localized to one hemi-gland. Gleason 3+3 at one core 1mm is acceptable in the untreated area. Preservation of sexual function is an important goal, but lack of erectile function should not exclude a patient from FT. CONCLUSIONS: This consensus provides a contemporary insight into expert opinion of patient selection for FT of clinically localized prostate cancer.

Novel antiproliferative flavonoids induce cell cycle arrest in human prostate cancer cell lines.

Epidemiologic studies have demonstrated an inverse association between flavonoid intake and prostate cancer (PCa) risk. The East Asian diet is very high in flavonoids and, correspondingly, men in China and Japan have the lowest incidence of PCa worldwide. There are thousands of different naturally occurring and synthetic flavonoids. However, only a few have been studied in PCa. Our aim was to identify novel flavonoids with antiproliferative effect in PCa cell lines, as well as determine their effects on cell cycle. We have screened a representative subgroup of 26 flavonoids for antiproliferative effect on the human PCa (LNCaP and PC3), breast cancer (MCF-7), and normal prostate stromal cell lines (PrSC). Using a fluorescence-based cell proliferation assay (Cyquant), we have identified five flavonoids, including the novel compounds 2,2'-dihydroxychalcone and fisetin, with antiproliferative and cell cycle arresting properties in human PCa in vitro. Most of the flavonoids tested exerted antiproliferative effect at lower doses in the PCa cell lines compared to the non-PCa cells. Flow cytometry was used as a means to determine the effects on cell cycle. PC3 cells were arrested in G2/M phase by flavonoids. LNCaP cells demonstrated different cell cycle profiles. Further studies are warranted to determine the molecular mechanism of action of 2,2'-DHC and fisetin in PCa, and to establish their effectiveness in vivo.

Telomerase activity in prostate cancer, prostatic intraepithelial neoplasia, and benign prostatic epithelium.

Telomerase is a ribonucleoprotein that synthesizes telomeric DNA on chromosomal ends. Telomerase activation has been seen in many immortal cell lines and cancers. Telomerase activity was analyzed in prostate carcinoma; in coexistent prostatic intraepithelial neoplasia (PIN), benign prostatic hyperplasia (BPH), atrophy and normal tissue; and in benign prostate glands. Telomerase activity was detected in 80 of 87 (92%) prostate cancers. Forty-one matched samples (from a total of 32 cases) were available for comparative analysis. The presence of telomerase activity in adjacent PIN, BPH, and normal tissue was correlated with telomerase activity in the malignant epithelium. In these adjacent tissues, telomerase activity was found in 11 of 15 (73%) PINs, 13 of 26 (50%) BPHs, and 1 of 6 (16%) atrophy and 4 of 11 (36%) normal tissues. In contrast to the BPH tissue from cancer-bearing glands, all 16 BPH specimens from patients only diagnosed with BPH were telomerase activity negative. In cancer samples, there was no correlation between telomerase activity and Gleason grade or preoperation prostate-specific antigen level. Our data indicate that telomerase activity is present in most prostate cancers. The high rate of telomerase activity in the benign-appearing areas of these glands may be attributed either to the presence of occult cancer cells or to early molecular alterations of cancer that were histologically inapparent.

Loss of cyclin-dependent kinase inhibitor p27Kip1 is a novel prognostic factor in localized human prostate adenocarcinoma.

p27Kip1 is a cyclin-dependent kinase inhibitor that negatively regulates cell proliferation by mediating cell cycle arrest in G1. This study was undertaken to assess the prognostic value of p27Kip1 in localized human prostate cancer. Archival material from 113 radical prostatectomy specimens obtained between 1985 and 1993 was stained immunohistochemically for p27Kip1 protein using a commercially available antibody. Patient charts were reviewed for preoperative serum prostate-specific antigen, clinical and pathological staging, Gleason tumor grade, time to biochemical and clinical recurrence, and survival. Strong p27Kip1 staining was uniformly seen in benign prostatic epithelial components in all tumor sections. p27Kip1 staining was reduced in most prostate cancers and was variable in prostatic intraepithelial neoplasia. Decreased p27Kip1 staining (<25% of nuclei stained positive for p27Kip1) correlated with seminal vesicle involvement (P = 0.0032) and with higher Gleason grade (P = 0.0114). On univariate analysis, low p27Kip1 predicted an increased risk of treatment failure in the node-negative cohort (P = 0.0037) and in the subset who did not receive neoadjuvant hormonal therapy (P = 0.049). Low p27Kip1 expression was an independent predictor of treatment failure on multivariate analysis of lymph node negative prostate cancers following radical retropubic prostatectomy (n = 102; P = 0.047). Seminal vesicle involvement (P = 0.034) and positive surgical margins (P = 0.047) were also independent prognostic factors for disease recurrence. In patients who received preoperative neoadjuvant hormonal therapy, low p27Kip1 in the pathological specimen was an even stronger predictor of outcome than it was in the entire group (n = 23, P = 0.015).

The role of lifestyle characteristics on prostate cancer progression in two active surveillance cohorts.

BACKGROUND: Although much research has examined the relationship between lifestyle and prostate cancer (PCa) risk, few studies focus on the relationship between lifestyle and PCa progression. The present study examines this relationship among men initially diagnosed with low- to intermediate-risk PCa and managed with active surveillance (AS). METHODS: Men enrolled in two separate AS programs were recruited for this study. Data regarding clinical, demographic and lifestyle characteristics were collected. Results were then compared between men whose disease remained low- to intermediate-risk and men whose disease progressed. RESULTS: Demographic, clinical and physical characteristics were similar between comparative groups and cohorts, with the exception that age at the time of diagnosis and questionnaire was increased among men whose disease progressed. Lifestyle scores among men who remained low- to intermediate-risk were higher than those whose risk progressed; however, scores were only significant in one cohort on univariable analysis. On multivariable analysis, the only predictor of progression was age at diagnosis. Physical activity was consistently higher in both low risk groups, although this difference was insignificant. Consistent differences in other lifestyle variables were not observed. CONCLUSIONS: Age remains an important predictor of PCa progression. Improving lifestyle characteristics among men initially managed with AS might help to reduce the risk of progression. Given the limitations of this study, more rigorous investigation is required to confirm whether lifestyle characteristics influence the progression of low- to intermediate-risk PCa.

Metformin and prostate cancer stem cells: a novel therapeutic target.

Prostate cancer is the second most frequently diagnosed cancer in the world. Localized disease can be effectively treated with radiation therapy or radical prostatectomy. However, advanced prostate cancer is more difficult to treat and if metastatic, is incurable. There is a need for more effective therapy for advanced prostate cancer. One potential target is the cancer stem cell (CSC). CSCs have been described in several solid tumors, including prostate cancer, and contribute to therapeutic resistance and tumor recurrence. Metformin, a common oral biguanide used to treat type 2 diabetes, has been demonstrated to have anti-neoplastic effects. Specifically, metformin targets CSCs in breast cancer, pancreatic cancer, glioblastoma and colon cancer. Metformin acts directly on the mitochondria to inhibit oxidative phosphorylation and reduce mitochondrial ATP production. This forces tumor cells to compensate by increasing the rate of glycolysis. CSCs rely heavily on mitochondrial oxidative phosphorylation for energy production. The glycolytic switch results in an energy crisis in these cells. Metformin could be used to exploit this metabolic weakness in CSCs. This would increase CSC sensitivity to conventional cancer therapies, circumventing treatment resistance and enhancing treatment efficacy. This review will explore the characteristics of prostate CSCs, their role in tumor propagation and therapeutic resistance and the role of metformin as a potential prostate CSC sensitizer to current anticancer therapies.

Megestrol acetate plus minidose diethylstilbestrol in the treatment of carcinoma of the prostate.

A multicenter randomized trial comparing megestrol acetate 120 mg/d, plus diethylstilbestrol (DES) 0.1 to 3 mg/d in patients with stage D2 prostate cancer was undertaken to compare the efficacy and toxicity of these two regimens. Pretreatment characteristics, including pathologic grade, performance status, age, and disease-related symptoms were similar in the two groups. Of 81 patients who have been entered in the study, 77 are evaluable for response and toxicity at a mean follow-up of 13.3 months. Using National Prostate Cancer Project (NPCP) criteria, no difference in response rate is noted (73% v 76%) or in disease-free survival and overall survival. The ability to suppress serum testosterone to castration levels and to maintain this suppression is equivalent in both treatment groups. However, treatment-related toxicity, including edema, hypertension, and gynecomastia, occurred at a significantly greater frequency, severity, and after a shorter treatment period in the DES-treated group. No difference in major cardiovascular events was noted. Since megestrol acetate plus minidose DES is equivalent to DES in achieving treatment responses in patients with carcinoma of the prostate, it is a preferable treatment because of its improved side-effect profile.

CUOG randomized trial of neoadjuvant androgen ablation before radical prostatectomy: 36-month post-treatment PSA results. Canadian Urologic Oncology Group.

OBJECTIVES: To test the hypothesis that neoadjuvant androgen ablation before radical prostatectomy reduces the likelihood of biochemical progression at 36 months. METHODS: Two hundred thirteen patients with localized prostate cancer were randomized to radical prostatectomy alone (Sx, n = 101) or a 12-week course of 300 mg of cyproterone acetate daily followed by surgery (CPA, n = 112). Biochemical progression (two consecutive detectable prostate-specific antigen [PSA] values) was determined for the entire group and by baseline PSA, Gleason score, clinical stage, and pathologic stage. RESULTS: The probability of biochemical progression at 36 months was similar in both groups (CPA 40.2%, Sx 30.1%; P = 0.3233). CPA patients with baseline serum PSA between 25 and 50 ng/mL had a lower probability of biochemical progression (CPA 63.5%, Sx 84.6%; P = 0.0038). No difference in the probability of biochemical progression was seen between groups when analyzed by clinical stage or Gleason score. When analyzed by pathologic margin status, no difference was observed in the probability of biochemical progression in patients with organ-confined disease (P = 0.4484). There was a trend for a higher probability of progression in the neoadjuvant arm in patients with positive and negative surgical margins (P = 0.0105, P = 0.0459; alpha = 0.005 with Bonferroni adjustment). CONCLUSIONS: Neoadjuvant androgen ablation with CPA reduces the positive margin rate significantly but does not result in a difference in biochemical progression at 3 years. This may be due to a lack of sufficient follow-up, insufficient power of the trial to demonstrate a small benefit, or a true lack of benefit of neoadjuvant androgen ablation before radical prostatectomy.

A multicenter, randomized, double-blind, placebo-controlled study to evaluate the safety and efficacy of terazosin in the treatment of benign prostatic hyperplasia.

OBJECTIVES: This study was designed to evaluate the safety and efficacy of the selective alpha 1-adrenoceptor blocker terazosin in the treatment of benign prostatic hyperplasia (BPH). METHODS: Two hundred twenty-four patients aged 50 to 80 years, who had a diagnosis of BPH based on medical history, physical examination, and digital palpation, were recruited from 11 different sites between January 1992 and January 1994. The study consisted of a screening phase, a placebo phase, a double-blind dose-titration phase, and a double-blind maintenance phase. RESULTS: Of the patients recruited, 164 entered the double-blind phase and of these 134 were evaluable. Only 11 patients withdrew because of an adverse event, 7 in the terazosin and 4 in the placebo group. Compared to placebo, terazosin significantly increased peak and mean urine flow rates without significantly affecting voided volume or postvoid residual volume. It significantly improved both the obstructive and irritative symptoms associated with BPH. Fifty-one patients from the terazosin group reported a total of 120 adverse events compared with 83 reported by 42 patients in the placebo group. The majority of these events were mild to moderate. Seventeen terazosin-treated patients reported hypotension-related adverse events and 4 withdrew from the study. However, concurrent treatment with antihypertensive agents did not affect the blood pressure response of the terazosin group. CONCLUSIONS: Overall, this study showed terazosin to be safe and effective in relieving the signs and symptoms of BPH and should be considered as a treatment alternative.

Synergistic effect of vitamin E and selenium in human prostate cancer cell lines.

Vitamin E and selenium are the two most popular dietary supplements used to prevent prostate cancer. The hypothesis that these antioxidants reduce prostate risk is being tested in the selenium and vitamin E chemoprevention trial (SELECT). We hypothesize that selenium potentiates vitamin E-induced inhibition of prostate cancer cell growth in vitro. Prostate cancer cell populations growing asynchronously were treated with a combination of vitamin E and selenium and processed for flow cytometric analysis. Prostate cancer cells treated with a combination of the antioxidants revealed that selenium potentiates vitamin E-induced inhibition of LNCaP cells in vitro. This was demonstrated by a reduction in the percentage of cells in the S phase. This crucial finding confirms our previous observations that antioxidant molecules act via distinct mechanistic pathways. These independent biological effects can be exploited in order to augment the anticancer properties of individual agents. These data also validate the two factorial design of the SELECT trial, permitting pairwise comparisons between agents in combination and alone.

Telomerase assay in renal cancer.

Telomeres are repeating sequences located at each end of eukaryotic chromosomes. These sequences function to protect chromosome positioning and replication (1-3). In vertebrates, telomere DNA consists of tandem repeats of TTAGGG, 10-15 kb pairs long (4). In most normal cells, DNA replication during mitosis results in the loss of telomere sequences 50-100 bp at the 5' ends of DNA termini (1,5). This sequence loss is mandated by the end-replication-splicing problem (Fig. 1). Thus, telomeres progressively shorten with age in somatic cells in culture and in vivo. In contrast, cancer cells and malignant cell lines retain telomere length despite repeated mitosis (6). This is believed to be an essential component of immortalization for most cells. Fig. 1. End-replication problem. As the replication fork proceeds from left to right, the leading strand proceeds to replicate one strand of original DNA (see B). The direction of the lagging strand is opposite to the direction of the replication fork and relies on the ligation of Okazaki fragments, which are primed with short stretches. Most RNA primer is never replaced with DNA (see C). Consequently, each round of replication produced a daughter chromosome. These are deficient in the sequences corresponding to the original 3' ends.

Randomized controlled trials in urologic oncology: a demographic analysis.

We examined randomized controlled trials in urologic oncology published in 1992. Particular emphasis was placed on the contribution of urologists and studies with a surgical arm. Randomized controlled trials in bladder, prostate, testis and renal carcinoma were identified by a structured MEDLINE search. Results were analyzed to determine modality of treatment, disease site, principal author, country of origin, cohort size, number of participating centers, source of funding and type of journal. MEDLINE retrieved 162 references of which 126 were excluded by title (10), abstracts (105) or articles (11) as not urologic oncology (7) or not a randomized controlled trials (119). Of the qualifying 36 randomized controlled trials, the site of the disease was bladder (44%), prostate (39%) renal (14%) and testis (3%). All except six randomized controlled trials compared medical therapies. Only five had a surgical arm and one had a radiation arm. Cohort size was > 100 in 67% of randomized controlled trials with most (56%) being multicenter trials. Participating countries were Europe, excluding the UK (35%), the US (23%), Japan (20%), Canada (13%), and the UK (10%). Urologists were the principal authors of 67% of the papers describing randomized controlled trials. The majority of trials were published in nonsurgical journals (50%). Funding for randomized controlled trials was from government (28%), pharmaceutical companies (19%), private sources (3%) and not stated (50%). Although randomized controlled trials are being conducted in urologic oncology, there are relatively few compared with trials using inferior study designs. A still smaller proportion of randomized controlled trials contain a surgical arm.

Bladder adenocarcinoma: 31 reported cases.

UNLABELLED: Retrospective review of 31 cases of bladder adenocarcinoma. METHODS: All patients diagnosed with adenocarcinoma of the bladder at the second affiliated hospital and commercial worker's hospital in Shanxi between 1985 and 1999 were reviewed. RESULTS: The cohort consisted of 31 patients, 25 with primary bladder adenocarcinoma, and 6 patients with urachal adenocarcinoma. Compared to the patients with primary adenocarcinoma, the urachal group were younger (67 versus 56 years), and more likely to be female (M:F 3:1 versus 1:2), and had a worse survival (45% versus 20% at 3 years). In the primary bladder adenocarcinoma group, the 3-year survival rate was 45% after radical cystectomy, and 33% after partial cystectomy. Local tumor recurrence after partial cystectomy was 25%. CONCLUSION: Urachal adenocarcinoma occurred in a younger age group with a female predominance compared to primary adenocarcinoma. Partial cystectomy was associated with a relatively high rate of local tumor recurrence.

Surveillance programs for early stage non-seminomatous testicular cancer: a practice guideline.

BACKGROUND AND PURPOSE: To identify an appropriate surveillance program for men with clinical stage I non-seminomatous germ cell tumors of the testis (NSGCT). MATERIALS AND METHODS: A systematic review of the published literature was combined with a consensus process, around the interpretation of the evidence in the context of conventional practice, to develop an evidence-based practice guideline. RESULTS: No randomized controlled trials (RCTs) comparing surveillance schedules were found, but data from 12 case series and one RCT which compared radiotherapy with surveillance were reviewed. Variations in the schedules were not associated with observed variations in relapse, salvage, or survival rates. CONCLUSIONS: Men with clinical stage I testicular cancer, as defined by a normal physical examination, normal radiological scans (computed tomography [CT]) and serum markers (alpha-fetoprotein [AFP] and beta-subunit of human chorionic gonadotropin (betaHCG) which are normal or fall within normal limits during their expected half-lives, are eligible for surveillance. A recommended surveillance schedule is as follows: 1) Physical examination, blood serum marker tests (AFP and HCG), and chest x-rays should be conducted every month in the first year, every 2 months in the second year, every 3 months in the third year, and every 6 months in the fourth and fifth years; and 2) CT scans of the abdomen and pelvis should be conducted every 3 months in the first year, every 4 to 6 months in the second year and every 6 months in the third year, and once a year in the fourth and fifth year.

Metformin enhances the antiproliferative and apoptotic effect of bicalutamide in prostate cancer.

BACKGROUND: Prostate cancer incidence and mortality vary dramatically by geographical location. Both are higher in developed countries. Some attribute this to westernized lifestyles of high-energy diets and limited physical activity with consequent obesity. Obesity and obesity-related diseases like diabetes cause hyperinsulinaemia, which upregulates pro-survival cell signalling. Previous work revealed diet-induced hyperinsulinaemia enhances prostate cancer xenograft growth in vivo. Metformin, an antidiabetic medication, reduces hyperinsulinaemia and also exhibits antineoplastic properties. Herein, we assess the potential additive benefit of combining bicalutamide antiandrogen therapy with metformin, in vitro and in vivo. METHODS: Using clonogenic assays, we assessed the effect of bicalutamide and/or metformin on clonogenicity in prostate cancer cell lines. Western blot and cell cycle analyses were used to elucidate mechanisms of interaction between the drugs in androgen receptor (AR)-positive (LNCaP) and AR-negative (PC3) cell lines. The combination treatment regimen was assessed in vivo using an LNCaP murine xenograft model. RESULTS: Micromolar bicalutamide or millimolar metformin caused a significant dose-dependent reduction in clonogenicity (P<0.001). Combination treatment further significantly reduced clonogenicity (P<0.005) with greater effects in AR-positive cells. Western blot and cell cycle analyses suggested differing mechanisms of interaction in AR-positive and -negative cell lines. Following combination treatment, LNCaP cells exhibited an altered cell proliferation (decreased phospho mammalian target of rapamycin expression) and perturbed cell cycle kinetics (G1/S cell cycle arrest). PC3 cells showed evidence of enhanced apoptosis (increased Bcl-2-associated X protein and decreased total caspase 3 expression). Markedly diminished tumour growth occurred following combination treatment in vivo (P<0.001). CONCLUSIONS: Combining bicalutamide and metformin significantly reduces prostate cancer cell growth further than either monotherapy. In AR-positive cells, this effect appeared to be mediated by reducing proliferation rates, whereas in AR-negative cells the combination treatment appeared to promote apoptosis. This combination drug regimen may improve prostate-cancer-specific survival by the direct antineoplastic properties outlined.