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PURPOSE: Although predicting outcome for men with clinically localized prostate cancer (PC) has improved, the staging system and nomograms used to do this are based on results from the North American health system. To be internationally applicable, these models require testing in cohorts from a variety of different health systems based on the predominant PC case identification methods used. PATIENTS AND METHODS: We studied 732 men with localized PC treated with radical prostatectomy and no preoperative therapy between 1986 and 1999 at one Australian institution to determine the effect of clinicopathologic features on disease-free survival. RESULTS: Preoperative serum prostate-specific antigen (PSA) concentration, Gleason score, pathologic stage, and year of surgery were independent predictors of outcome. Although margin status demonstrated only a trend toward significance in multivariate modeling overall, it proved to be independent in subgroups based on later year of surgery (1986 to 1994 v 1995 to 1998), preoperative PSA of less than 10 ng/mL, and Gleason score > or = 7. Adjuvant radiation therapy improved disease-free survival rates in patients with multiple surgical margin involvement. CONCLUSION: This work confirms the prognostic significance of pathologic stage, Gleason score, and preoperative serum PSA. In the context of a contemporaneous screening effect in Australia, these findings may have implications for methods that predict outcome following surgery as screening becomes more prevalent in a population. The independent prognostic effect of margin status may alter with an increase in the proportion of screening-identified PCs. Staging systems and nomograms that predict outcome following surgery require validation in cohorts with different health practices before being universally applied.

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The role of estrogen and its receptors in the etiology and progression of prostate cancer (PC) is poorly understood. In normal and malignant human prostate, estrogen receptor-alpha is expressed only in the stroma, whereas estrogen receptor-beta (ERbeta) is present in both normal stroma and epithelium. Because loss of ERbeta expression is associated with prostate hyperplasia in ERbeta-null mice, this study determined patterns of ERbeta expression in normal, hyperplastic, and malignant human prostate and associations with clinical outcome. Five normal prostates from organ donors and 159 radical prostatectomy specimens from patients with clinically localized PC were assessed for ERbeta expression using immunohistochemistry. ERbeta-positivity was defined as > or =5% of cells demonstrating nuclear immunoreactivity. All of the five normal prostates showed strong ERbeta-nuclear staining in >95% of the epithelium and 35% of the stromal cells. The number of ERbeta-positive cases declined to 24.2% (38/157) in hyperplasia adjacent to carcinoma and 11.3% (18/159) in PCs. ERbeta-positivity was related to decreased relapse-free survival (log-rank P = 0.04). Thus, loss of ERbeta expression is associated with progression from normal prostate epithelium to PC, whereas those cancers that retained ERbeta expression were associated with a higher rate of recurrence. These data identify the need to further investigate the potential role of ERbeta in the regulation of prostate epithelial cell proliferation and the functional consequences of decreased ERbeta expression in the evolution of PC.

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Prostate cancer (PC) is the most commonly diagnosed male cancer in industrialized societies. No molecular markers of PC progression or outcome with proven clinical utility have been described. Because the loss of normal cell cycle control is an early event in the evolution of cancer, we sought to determine whether changes in expression of the cyclin-dependent kinase inhibitor, p16INK4A, predicted outcome in this disease. We screened a cohort of 206 patients with clinically localized PC treated with radical prostatectomy for overexpression of the INK4A gene, the product of which inactivates the G1-phase cyclin dependent kinases, Cdk4 and Cdk6. p16INK4A protein expression was evaluated by immunohistochemistry in areas of high-grade intraepithelial neoplasia (HGPIN), a precursor to invasive disease, and of cancer in the same specimen. Data were evaluated for disease relapse using the Kaplan-Meier method and in a Cox proportional hazards model by assessing p16INK4A status in areas of HGPIN and cancer with other variables of known clinical relevance. Overexpression of p16INK4A in HGPIN and cancer was correlated with, but independent of, pathological stage and was associated with early relapse in PC patients treated with radical prostatectomy (log-rank test, P < 0.001). In a multivariate model adjusted for Gleason grade, pretreatment prostate-specific antigen levels, pathological stage, and margin status, overexpression of p16INK4A in HGPIN was an independent predictor of disease relapse and increased the risk of recurrence 2.24-fold (95% confidence interval, 1.28-3.93). These data provide the first evidence for a prognostic marker in HGPIN. The clinical utility of p16INK4A status in stratifying patients for aggressive treatment very early in the disease process, potentially several years prior to the onset of invasive disease, requires further investigation.

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The molecular basis of androgen-independent prostate cancer is unknown; however, functional androgen receptor (AR) signaling is maintained after the acquisition of hormone-refractory disease. Because normal and malignant prostate epithelial cell proliferation is regulated by androgen stimulation via both the AR-positive stroma and epithelium, we sought to evaluate patterns of AR expression in these cells and to determine any relationships with prostate cancer progression. AR expression in the malignant epithelium and associated periepithelial and nonperiepithelial stroma was measured in a cohort of 96 patients with clinically localized prostate cancer treated with radical prostatectomy. Data were evaluated for disease relapse using the Kaplan-Meier method and in a Cox proportional hazards model with other variables of known clinical relevance, including Gleason score, pathological stage, clinical stage, and pretreatment prostate-specific antigen concentration. Concurrent overexpression of AR (> or = 70% positive nuclei) in the malignant epithelium and loss of AR immunoreactivity in the adjacent periepithelial stroma (< or = 30%) was associated with higher clinical stage (P = 0.01), higher pretreatment prostate-specific antigen level (P = 0.03), and earlier relapse after radical prostatectomy (log-rank P = 0.009). These data identify a pattern of AR expression in malignant epithelium and adjacent stroma that is associated with a poor clinical outcome in prostate cancer. Equally important, they identify the need to further investigate the mechanistic basis of loss of AR expression in the malignant stroma and its potential role in deregulation of prostate epithelial cell proliferation.

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The role of p53 in the pathogenesis of, and as a predictive biomarker for, localized prostate cancer (PCa) is contested. Recent work has suggested that patterns of p53 nuclear accumulation determined by immunohistochemistry are prognostic, whereas studies using other methods question the role of p53 mutations in predicting outcome. We studied 263 men with localized PCa treated with radical prostatectomy to determine whether p53 nuclear accumulation predicts relapse and disease-specific mortality. We combined two p53 immunohistochemistry scoring systems: (a) percentage of p53-positive tumor nuclei in all major foci of cancer within the prostate; and (b) clustering, where the presence of 12 or more p53-positive cells within a x 200 power field was deemed "cluster positive." Analysis was undertaken using chi2, Kruskal-Wallis, and Mann-Whitney tests for clinicopathological variables and the Kaplan-Meier method, log-rank test, and univariate and multivariate Cox regression modeling for evaluation of contribution to relapse and disease-specific survival. At mean follow-up of 55.1 months (range, 4.9-123.0 months), 39% (102 of 263) of patients had relapsed and 2.3% (6 of 253) had died of PCa. Pretreatment serum prostate-specific antigen concentration, pathological tumor stage, lymph node involvement, Gleason score, and p53 nuclear accumulation, as determined by either percentage score or cluster status, were independent predictors of relapse in multivariate analysis. Clustering of p53-positive cells distinguished between favorable and poor prognosis patients within the lowest p53-positive stratum (>0 to <2%) and was the most discriminatory threshold for predicting relapse in the entire cohort. p53 status predicted outcome in patients with a Gleason score of 5 and above but not those with a score of 4 and below. In patients treated with neoadjuvant hormonal therapy, p53 cluster positivity carried a 90% (19 of 21) risk of relapse by 36 months. All six patients who died from PCa in the period of the study exhibited p53 nuclear accumulation in 20% or more tumor nuclei. This study demonstrates strong relationships between p53 nuclear accumulation and relapse and disease-specific mortality in a large series of localized PCas. Furthermore, the presence of clusters of p53-positive nuclei delineates a group of patients with poor prognosis not identified by traditional scoring methods and supports the hypothesis that p53 dysfunction within PCa may exist in foci of tumor cells that are clonally expanded in metastases.

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The disease course of localized prostate cancer is highly variable, and patients potentially curable by aggressive management are not readily identified by current clinical practice. Chondroitin sulfate (CS) glycosaminoglycan is a candidate biomarker as elevated levels of CS in peritumoral stroma of prostate cancer have been associated with prostate-specific antigen (PSA) failure. Immunoreactive CS was measured using image analysis of archived radical prostatectomy tissues, obtained from 157 men with a median of 47 months (range, 16-111 months) clinical follow-up. CS level, Gleason score, and preoperative serum PSA levels were independent predictors of PSA failure by Cox's multivariate analysis. Patients with low CS levels had significantly fewer PSA failures after radical prostatectomy than patients with high levels of CS (Kaplan-Meier plot; 32% PSA failures at 5 years for CS mean integrated absorbance cut point < 7.0 versus 50% for CS > or = 7.0, P = 0.0001). In the subgroup of patients with preoperative serum PSA levels < 10 ng/ml, CS was particularly useful in discriminating retrospectively those patients most suited for surgery (Kaplan-Meier plot; 14% PSA failures at 5 years for CS mean integrated absorbance cut point < 7.0 versus 47% for CS > or = 7.0, P = 0.0001). We conclude that measurements of CS level can assist in predicting patient outcome after surgery. Additionally, our data suggest that the combination of CS and PSA measurements may improve outcome prediction for patients with intermediate Gleason scores.

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PURPOSE: This study assessed whether a specific association exists between atypical nevi and germ cell tumors (GCT). METHODS: A prospective comparison was performed on a cohort of 129 unselected patients with GCT and a series of 153 healthy men. Three or more of the following criteria were required for diagnosis of multiple atypical nevi: greater than 5 mm in diameter; variegated color, often speckled black/brown, with irregularly distributed pigmentation; irregular outline or indistinct border; and at least three such lesions. RESULTS: Prevalences for multiple atypical nevi in patients with GCT and in healthy controls were 37% and 15%, respectively (P < .01). Two patients with these lesions also had documented malignant melanoma. In contrast, 16% of patients with GCT had a history of testicular maldescent (the most common known risk factor), compared with 5% of healthy controls (P < .01). CONCLUSION: Multiple atypical nevi occur with a statistically significant increased prevalence in patients with GCT as compared with healthy controls, and constitute one of the most common known clinical associations with this malignancy. These data may be of relevance for our understanding of the biology of GCT and of malignant melanoma, in the design of screening programs for testis cancer, and in the follow-up evaluation of patients with each of these disorders.

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Thirty patients with hormone-refractory prostate cancer were treated with cycles of oral cyclophosphamide (100 mg/m2/day for 14 days, with a 14-day gap). Eighteen patients had a significant improvement in symptoms of advanced disease, 6 had objective partial remissions and 13 had stabilisation of disease (criteria of National Prostatic Cancer Project). The median survival from the time of diagnosis was 33.3 months, and from the commencement of cyclophosphamide 12.7 months. The treatment was well tolerated. oral cyclophosphamide is active in the treatment of advanced hormone-refractory prostate cancer and yields symptomatic and objective remissions without undue side effects. This observation requires validation, with further testing of its impact on survival in randomised clinical trials.

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During late 1991, a series of severe adverse events involving thrombocytopenia, renal insufficiency and thrombotic episodes was observed in patients receiving emetogenic chemotherapy. Two patients died, one of renal failure and one of cerebral haemorrhage in the presence of thrombocytopenia. Other severe side effects included thrombosis of the aorta causing paraplegia and multifocal cerebral infarctions. Common exposure features included the use of ondansetron and dexamethasone as antiemetics, and in most of the cases high dose (100 mg/M2 or more) cisplatin. Retrospective review of a series of patients treated with similar cytotoxic regimens for similar diseases before the use of ondansetron revealed no similar adverse effects, but no substantial differences were observed in renal function or haematologic toxicity in the two groups overall. Sporadic adverse vascular events have been observed before the use of ondansetron. The mechanism remains unknown, and it is not clear whether ondansetron was a factor in the unusual incidence of such events in the present series.

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Twenty patients with histologically confirmed metastatic or recurrent renal carcinoma were treated in a phase II study with alpha-interferon (2-5 x 10(6) U/m2 subcutaneously, 3 times a week). Nineteen patients had multiple sites of disease and 18 had previously undergone nephrectomy; 9 had an ECOG performance status of 0.1, and 11 had a performance status of 2-3. There was one partial response, yielding an overall response rate of 5%. Treatment was well tolerated, although 7 patients developed influenza-like symptoms, and in 2 cases this was sufficiently severe for the patients to request cessation of treatment. As a single agent at this dose schedule, alpha-interferon has minimal activity in the treatment of renal carcinoma and cannot be recommended as standard therapy. The difference in outcome between this and some published series may reflect the stringent requirement for histological proof of the presence of metastases.

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It is apparent that MTX is a useful agent in the treatment of rheumatoid arthritis resistant to first and second line therapies. However, despite its long term use in this disease, considerable uncertainty exists about the basic pharmacokinetics of low dose oral MTX and therefore about its pharmacodynamics. It is probable that when MTX is re-examined with the help of modern analytical technology in a rheumatoid setting that pharmacological insights to the variability in dose-response relationships for efficacy and certain toxicities may emerge. There is still considerable uncertainty of the hepatotoxic potential of MTX. Further investigation of the accumulation of active polyglutamated MTX in liver may throw light on the likelihood of promoting iatrogen disease and perhaps the contribution of oral administration to this problem. Finally, examination of dose-response relationship utilising accurate pharmacokinetics may help to establish guidelines for the safe and effective usage of MTX in rheumatoid arthritis.

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The pharmacokinetic disposition of tiazofurin in plasma and cerebrospinal fluid was examined in rhesus monkeys. Tiazofurin was readily detectable in both plasma and cerebrospinal fluid within 20 min of commencement and for 24 h after a short i.v. infusion of the drug. The mean clearance of tiazofurin from plasma was 70 +/- 23 (SD) ml/min/sq m after a dose of 100 mg/kg and 106 +/- 38 ml/min/sq m after a dose of 500 mg/kg with no evidence of dose dependency. The data for plasma elimination of tiazofurin were fit to a triexponential equation for comparison with data from other species. The t 1/2 alpha was 0.23 h, t 1/2 beta was 1.9 to 2.0 h, and t 1/2 gamma was 6.8 to 7.1 h. The ratio of area under the cerebrospinal fluid drug concentration-time curve to the area under the plasma drug concentration-time curve was 0.28, which suggests significant penetration of the blood-brain barrier. These results demonstrate the propensity of tiazofurin to enter the cerebrospinal fluid and, probably, the brain, and suggest a potential role for this agent in the treatment of central nervous system cancer.

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The effects of cimetidine (1 g/day) on theophylline disposition and metabolism were examined in smokers and non-smokers for single dose intravenous and chronic oral administration of theophylline. In the intravenous study the effect of cimetidine on plasma theophylline clearance was more marked in smokers (22.7% reduction) than in non-smokers (12.2% reduction). Similarly, in the multiple dose study the effect of cimetidine on theophylline clearance was greater in smokers (28.3% decrease) than in non-smokers (11.3% decrease). The reduction in clearance was largely due to a reduction in metabolic clearances by 3-demethylation ( Cl3DM ) and 1-demethylation ( Cl1DM ) with no significant effect on clearance by 8-oxidation ( Cl80X ). There was a strong correlation between Cl3DM and Cl1DM (r = 0.98, p less than 0.001) in both control and cimetidine study phases, whereas other correlations between partial clearances were less marked and were not apparent during the cimetidine phase. The results are consistent with the view that 1- and 3-demethylation of theophylline are carried out by a common form of cytochrome P-450 which is selectively induced by cigarette smoking and preferentially inhibited by cimetidine.

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Carboplatin (CBDCA; NSC 241240) is a second-generation platinum coordination compound which in preclinical testing was found to be less nephrotoxic and emetogenic than cis-diamminedichloroplatinum (CDDP), while retaining a broad spectrum of antitumor activity. We have conducted a Phase I trial of CBDCA in 38 patients with advanced carcinoma. The drug was given without hydration as a 24-hr constant i.v. infusion on Day 1 of a 28-day cycle. Seventy-five cycles of CBDCA were administered in eight dose levels ranging from 20 to 320 mg/sq m. Dose-limiting toxicity was myelosuppression, primarily thrombocytopenia, occurring between Days 14 and 28 of the cycle. Myelosuppression was first observed at a dose of 240 mg/sq m and became dose-limiting at 320 mg/sq m, which is the recommended dose for Phase II trial. Other toxicities included nausea and vomiting and reversible renal failure seen in two patients with low normal pretreatment creatinine clearances. No consistent changes were seen on serial audiograms. Plasma concentrations of total and ultrafilterable platinum were measured by flameless atomic absorption spectrophotometry. Following cessation of the infusion, a half-life of 170 +/- 34 min (S.D.) was found for CBDCA-derived ultrafilterable platinum. In vitro clonogenic assay of a CDDP-sensitive human ovarian cancer cell line using clinically achievable drug concentrations suggests that prolonged infusions of CBDCA may be more cytotoxic than bolus administration. In this study, minimal responses were seen in two patients with ovarian carcinoma who had failed previous combination chemotherapy including CDDP. In addition, three patients with refractory metastatic breast cancer responded to CBDCA (two minimal responses and one partial response) with remission durations averaging 3 months. CBDCA behaves as predicted by preclinical studies with different toxicities from CDDP and apparent activity in breast cancer.

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Historically, the concept of metabolic activation was first forwarded to explain the in vivo activity of certain carcinogenic chemicals that without prior metabolism were chemically inert and biologically inactive. Subsequently, the concept has been extended to explain the effects of many different classes of chemicals causing diverse toxicities. Because of its major role in drug metabolism, the liver is a prominent site for toxic injury by agents requiring metabolic activation. The liver can also be the source of reactive metabolites that damage extrahepatic organs. But, organ selective toxicity can also result from the in situ metabolic activation of foreign chemicals in extrahepatic target tissues such as the lungs and the kidneys. Moreover, extrahepatic tissues generally are much more heterogeneous in cellular composition compared to the liver, and the localization of drug metabolizing enzymes in certain cell populations may result in highly cell selective toxic injury. The significance of metabolic activation and toxicity--and the importance of the particular chemical structure of individual compounds, as well as host factors such as species, age, sex, and pretreatment effects--on target-organ-selective toxicity by reactive metabolites are illustrated by studies with various furan derivatives, an important class of environmental chemicals.

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The influence of liver volume and body weight on plasma theophylline clearance was investigated in asthmatic children and adults. A linear relationship (r = +0.99) was demonstrated between ideal body weight and liver volume estimated by an ultrasonic scanning technique. Age-related changes in liver volume-to-body weight ratio could account for only 30% of differences in plasma theophylline clearance (1/h/kg) between children and adults. It is summized that increased hepatic mixed function oxidase activity is the major contributor to the higher plasma theophylline clearance in children.

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The absolute oral bioavailability of a sustained release theophylline tablet (Nuelin-SR250), given 12 hourly was determined in 14 asthmatic children aged 5 to 13 years. In 4 of the patients, mean bioavailability of the fourth dose was 38.9 +/- 8.4% and that of the sixth dose was 67.9 +/- 25.9% (p less than 0.05) in the other ten patients. This suggests steady-state had not been achieved after four doses. In the initial study with 9 patients, a significant diurnal variation in predose plasma theophylline concentrations was observed, as the mean morning predose concentrations were 2.9 fold greater than the mean evening predose concentrations (p less than 0.005). Dual peak plasma concentrations occurred in 5 out of the 9 patients. The mechanism of this diurnal variation was investigated in a further 5 asthmatic children (10.8 years +/- 1.6). Morning and night steady-state plasma theophylline concentrations during a continuous intravenous infusion of aminophylline were not different (14.9 +/- 5.3 mg/l vs. 15.6 +/- 5.9 mg/l), demonstrating that there was no diurnal variation in the plasma clearance of theophylline. The diurnal variation in predose concentrations with Neulin-SR250 was confirmed with the morning concentrations again being 2.6 fold greater than those in the evening. However, bioavailability was not significantly different for day (09.00-21.00) and night (21.00-09.00) dosing intervals after doses 6 and 7 respectively of Nuelin-SR250. The plasma concentration versus time profiles suggested that the diurnal variation in predose concentrations was due to slower absorption of the evening dose.

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