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B J Miles

Publications and source records attributed to B J Miles.

At least 19 recordsLinked to original sources
PubMed2005

The emerging role of the PI3-K-Akt pathway in prostate cancer progression.

The PI3-K-Akt pathway plays a central role in the development and progression of prostate cancer and other malignancies. We review original studies and summarize relevant sections of previous reviews concerning the relationships between abnormalities in the PI3-K-Akt pathway and prostate cancer progression. We discuss laboratory and clinical data that indicate gene perturbation and dysregulation of PI3-K-Akt pathway is common in prostate cancer and other malignancies. We further discuss the critical role of the PI3-K-Akt pathway in the oncogenic signaling network and provide examples that establish the PI3-K-Akt pathway as a focal point for the future development of informative biomarkers and effective therapies for prostate cancer.

Biomarkers, Tumor↗
PubMed2001

Prostate-specific antigen response and systemic T cell activation after in situ gene therapy in prostate cancer patients failing radiotherapy.

In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence after radiotherapy who received single or repeated cycles of replication-deficient adenoviral vector (ADV)-mediated herpes simplex virus-thymidine kinase (HSV-tk) plus ganciclovir (GCV) in situ gene therapy with respect to serum PSA levels, alterations in immune cells, and numbers of apoptotic cells in needle biopsies. An initial cycle of HSV-tk plus GCV gene therapy caused a significant prolongation of the mean serum PSA-doubling time (PSADT) from 15.9 to 42.5 months (p = 0.0271) and in 28 of the injected patients (77.8%) there was a mean PSA reduction (PSAR) of 28%. It took a mean of 8.5 months for the PSA to return to the initial PSA (TR-PSA) value. A repeated cycle of gene therapy failed to significantly extend PSADT but did result in significant increases in PSAR (29.4%) and TR-PSA (10.5 months). Moderately increased serum adenovirus antibody titers were generally observed 2 weeks after initial vector injection. Also at this time there was a statistically significant increase in the mean percent of CD8(+) T cells positive for the HLA-DR marker of activation in peripheral blood (p = 0.0088). Studies using prostate biopsies obtained at the same time point demonstrated that vector DNA was detectable by PCR in most samples yet all patients remained positive for prostate cancer in at least one biopsy core. Further analysis demonstrated a correlation between the level of CD8(+) cells and the number of apoptotic cells in biopsies containing cancer cells (p = 0.042). We conclude that repeated cycles of in situ HSV-tk plus GCV gene therapy can be administered to prostate cancer patients who failed radiotherapy and have a localized recurrence. Biological responses to this experimental therapy including increases in PSADT, PSAR, and TR-PSA, and activated CD8(+) T cells present in the peripheral blood, were demonstrated. Interestingly, the density of CD8(+) cells in posttreatment biopsies correlated with the number of apoptotic cells.

Adenoviridae↗
PubMed2001

Methods to improve efficacy of intravesical mitomycin C: results of a randomized phase III trial.

BACKGROUND: Intravesical chemotherapy (i.e., placement of the drug directly in the bladder) with mitomycin C is beneficial for patients with superficial bladder cancer who are at high risk of recurrence, but standard therapy is empirically based and patient response rates have been variable, in part because of inadequate drug delivery. We carried out a prospective, two-arm, randomized, multi-institutional phase III trial to test whether enhancing the drug's concentration in urine would improve its efficacy. METHODS: Patients with histologically proven transitional cell carcinoma and at high risk for recurrence were eligible for the trial. Patients in the optimized-treatment arm (n = 119) received a 40-mg dose of mitomycin C, pharmacokinetic manipulations to increase drug concentration by decreasing urine volume, and urine alkalinization to stabilize the drug. Patients in the standard-treatment arm (n = 111) received a 20-mg dose without pharmacokinetic manipulations or urine alkalinization. Both treatments were given weekly for 6 weeks. Primary endpoints were recurrence and time to recurrence. Treatment outcome was examined by use of Kaplan-Meier analysis with log-rank tests. Statistical tests were two-sided. RESULTS: Patients in the two arms did not differ in demographics or history of intravesical therapy. Dysuria occurred more frequently in the optimized arm but did not lead to more frequent treatment termination. In an intent-to-treat analysis, patients in the optimized arm showed a longer median time to recurrence (29.1 months; 95% confidence interval [CI] = 14.0 to 44.2 months) and a greater recurrence-free fraction (41.0%; 95% CI = 30.9% to 51.1%) at 5 years than patients in the standard arm (11.8 months; 95% CI = 7.2 to 16.4 months) and 24.6% (95% CI = 14.9% to 34.3%) (P =.005, log-rank test for time to recurrence). Improvements were found in all risk groups defined by tumor stage, grade, focality, and recurrence. CONCLUSIONS: This study identified a pharmacologically optimized intravesical mitomycin C treatment with statistically significantly enhanced efficacy.

Administration, Intravesical↗
PubMed2001

In vivo surgical resection plus adjuvant gene therapy in the treatment of mammary and prostate cancer.

Adenoviral-mediated gene therapy delivery, combining the herpes simplex virus thymidine kinase gene (Ad-tk) with gancyclovir, has been evaluated as a treatment modality for numerous tumors in the laboratory and in the clinics. As a single modality, gene therapy has shown some promising local and systemic results but no curative success. Surgery is the standard of care for many solid tumors. However, minor residual tumor following surgical resection can lead to local recurrence, and surgery is neither efficient nor plausible for metastatic disease. In this study, two tumor models were used to evaluate the effects of Ad-tk gene therapy as an adjuvant to surgery. Subcutaneous mammary- and prostate-derived tumors were produced in syngeneic mice. To evaluate systemic effects, tumor cells were injected intravenously, with subsequent formation of lung nodules. The subcutaneous tumors were surgically resected and the tumor bed was bathed with saline or Ad-tk. The animals were evaluated for toxicity, local tumor recurrence, survival, and lung nodule formation. No evidence of additional toxicity was observed. In the less aggressive mammary model, the time to recurrence was increased from 11.7 (+/-1.0) days to 22.7 (+/-5.5) days. In the prostate model, recurrence went from a mean of 17.3 (+/-5.6) to 22.6 (+/-6.8) days. Survival was also improved from a mean of 19.7 (+/-1.1) to 32.3 (+/-4.8) and 26.1 (+/-5.0) to 34.1 (+/-6.1) days in the mammary and prostate models, respectively. Evidence of systemic benefits from the use of adjuvant Ad-tk therapy was demonstrated by a significant reduction in lung nodules from a mean of 17 to 3.5. These results suggest that Ad-tk gene therapy may be a useful adjuvant for patients undergoing surgery for treatment of cancer.

Adenoviridae↗
PubMed2001

Bilateral nerve grafting during radical retropubic prostatectomy: extended follow-up.

OBJECTIVES: To confirm the benefit of using an interposition sural nerve graft at the time of radical retropubic prostatectomy in an extended series of men with at least 1 year of follow-up. We previously reported the return of erectile function after resection of both cavernous nerves. METHODS: Twenty-eight potent men with clinically localized prostate cancer underwent radical retropubic prostatectomy with deliberate wide bilateral neurovascular bundle resection and the placement of bilateral nerve grafts. Erectile dysfunction questionnaires and patient interviews were completed at 6-month intervals. A minimum of 12 months of follow-up (mean 23 +/- 10 months) was obtained for 23 men (mean age 58 +/- 6 years). A control group of 12 men who underwent bilateral nerve resections, but declined nerve graft placement, was also followed up. RESULTS: Of the 23 men, 6 (26%) had spontaneous, medically unassisted erections sufficient for sexual intercourse with vaginal penetration. An additional 6 men (26%) described "40% to 60%" spontaneous erections (fullness, no rigidity, not able to penetrate). Ten men (43%) had intercourse with sildenafil. No demonstrable erections occurred before 5 months postoperatively. The greatest return of function thus far was observed at 18 months after surgery. CONCLUSIONS: This surgical technique continues to show promise as an advance in prostate cancer surgery. The results of this study demonstrated recovery of erectile function in men who underwent bilateral nerve graft placement during radical retropubic prostatectomy when both cavernous nerves were deliberately resected.

Case-Control Studies↗
PubMed2001

Bilateral nerve graft during radical retropubic prostatectomy: 1-year followup.

PURPOSE: With the interposition of a sural nerve graft to replace resected cavernous nerves at radical retropubic prostatectomy, we have previously reported the return of effective erectile function. We determine the efficacy of this procedure in a series of men with at least 1-year followup. MATERIALS AND METHODS: A total of 12 potent men (mean age plus or minus standard deviation 57 +/- 6 years) with clinically localized prostate cancer underwent radical retropubic prostatectomy, with deliberate wide bilateral neurovascular bundle resection and placement of bilateral nerve grafts. A series of patient and partner erectile dysfunction questionnaires, and patient interviews were performed at 3, 6, 12 and 18 months postoperatively. Only results for those men with a followup of 12 months or greater (mean 16 +/- 4) are presented. A control group of 12 men who had undergone bilateral nerve resection but declined nerve graft placement, was also followed. RESULTS: Of the 12 men 4 (33%) had spontaneous medically unassisted erections sufficient for sexual intercourse with vaginal penetration. An additional 5 (42%) men describe "40 to 60%" spontaneous erections, with fullness, no rigidity and not able to penetrate. Overall, 9 (75%) men had return of erectile activity. No demonstrable erections occurred before 5 months postoperatively. The greatest return of function was observed at 14 to 18 months after surgery. CONCLUSIONS: This surgical technique has minimal morbidity and represents a significant advance in prostate cancer surgery in men requiring bilateral nerve resection. Our study clearly demonstrates recovery of erectile function in men who underwent bilateral nerve graft placement during radical retropubic prostatectomy when both cavernous nerves were deliberately resected.

Aged↗
PubMed2001

In situ gene therapy for prostate cancer: immunomodulatory approaches.

The development of effective treatments for prostate cancer is thwarted by the natural history of the disease. The biological and clinical potential of most individual cancers is uncertain. In many cases the disease will not progress to clinical significance but experimental and clinical studies indicate that prostate cancer can and may metastasis early in the course of the disease from relatively small foci (i.e., not necessarily the largest or index cancer). Localised prostate cancer is potentially curable with localised therapies (radical prostatectomy or irradiation therapy). However, there are no curative therapies for metastatic prostate cancer. Gene therapy, especially those approaches with an immunomodulatory component, may provide additional therapeutic options with the potential to affect both localised and systemic disease. We have pioneered the development and application of in situ gene therapy protocols using adenoviral vectors to transduce specific genes that generate cytotoxic activity and/or a systemic antitumour immune response. In addition we have completed initial studies that demonstrate the therapeutic potential of adenoviral vector-mediated gene modified cell-based vaccines. Our review discusses preclinical studies focused on the development of immunostimulatory in situ gene therapy approaches that hopefully will provide novel and effective treatments for localised and metastatic prostate cancer.

Animals↗
PubMed2001

Optimal combinations of systematic sextant and laterally directed biopsies for the detection of prostate cancer.

PURPOSE: The standard sextant protocol for obtaining transrectal ultrasound guided biopsy of the prostate has been shown to underestimate the presence of prostate cancer. Studies have demonstrated an increased cancer detection rate with additional laterally directed biopsies. We compared the sensitivity of individual biopsy cores and evaluated combinations of these cores to identify an optimal biopsy strategy. MATERIALS AND METHODS: A total of 396 consecutive patients underwent biopsy of the lateral peripheral zone in addition to standard sextant biopsy. The cancer detection rate for each biopsy core was calculated. The sensitivity of different combinations of biopsy cores was compared with those of standard sextant biopsies and with a 12 core biopsy protocol that combined the standard sextant biopsy with a complete set of laterally directed cores. RESULTS: Cancer was detected in 160 of 396 (40.3%) patients. Of the possible combinations of biopsy cores a strategy that included laterally directed cores at the base, mid gland and apex of the prostate with mid lobar base and apical cores detected 98.5% of cancers. The detection rate of this 10 core biopsy regimen was significantly better than that of the standard sextant protocol (p < or =0.001), and was equivalent to that of the 12 core regional biopsy (p > or =0.302). CONCLUSIONS: The standard sextant protocol failed to detect a large proportion of cancers located laterally in the peripheral zone. A 10 core biopsy regimen that combined laterally directed cores at the base, mid gland and apex of the prostate with mid lobar biopsy cores at the base and apex maximizes the sensitivity of transrectal ultrasound guided systematic biopsy.

Biopsy↗
PubMed2001

Time trade-off utility modified to accommodate degenerative and life-threatening conditions.

The time trade-off is often argued to be the preferred utility assessment method. When measuring current health in its classic form, it involves a comparison of two certainties: perfect health and current health, each for a fixed period of time and followed by death. This makes the time trade-off insensitive to patient fears regarding premature death or worsening health. We suggest the classic time trade-off be modified to include subjective rather than actuarial life expectancy, and relaxation of the current health option to include uncertainty in quantity and quality of life. We illustrate the mechanics of this modified time trade-off and report a preliminary application to 122 men presenting to a prostate cancer screening program. Further analysis of this modified time trade-off appears warranted.

Attitude to Health↗
PubMed2000

Suicide gene therapy for prostate cancer using a replication-deficient adenovirus containing the herpesvirus thymidine kinase gene.

Current therapies for localized prostate cancer include radical prostatectomy, local radiation therapy, and cryoablation and are associated with a high rate of cure and acceptable morbidity. However, for men who have failed primary curative attempts or have metastatic disease, no effective therapy associated with acceptable morbidity exists. "Suicide" gene therapy delivered alone or in combination with other forms of treatment could potentially provide simultaneous efficacy against localized and systemic disease via the generation of cytotoxic activity and/or systemic immunity to the cancer. In this article we discuss our preclinical and clinical experience with a herpes-simplex-virus thymidine kinase/ganciclovir gene-therapy protocol for prostate cancer.

Adenoviridae↗
PubMed2000

Diagnosis and management of incidental ureterocele during the treatment of clinically localized prostate cancer.

Two instances of simultaneous diagnosis of prostate cancer and ureterocele were recently identified. In one patient an ectopic ureterocele in a duplex system with an obstructed upper pole was unroofed at the time of radical prostatectomy. Surgical excision of the ureterocele wall provided decompression of the obstructed system. In a second patient, bilateral intravesical ureteroceles associated with normal renal units were left untreated. Complications were not associated with the untreated ureteroceles. On rare occasions a ureterocele may be discovered incidentally during the evaluation of patients with prostate cancer. When radical prostatectomy is planned, treatment of the ureteroceles should be determined by the ureterocele's size, anatomic configuration, and location and by the degree of obstruction of the affected renal unit. Surgical excision of the ureterocele at the time of radical prostatectomy may be the best approach for patients requiring treatment.

Adenocarcinoma↗
PubMed2000

Assessing quality of life in men with clinically localized prostate cancer: development of a new instrument for use in multiple settings.

BACKGROUND: Quality of life in prostate cancer patients with clinically localized disease has become the focus of increasing attention over the past decade. However, few instruments have been developed and validated to assess quality of life specifically in this patient population. OBJECTIVE: The purpose of this investigation was to create a comprehensive, multi-scale quality of life instrument that can be tailored to the needs of the clinician/investigator in multiple settings. DESIGN, SUBJECTS, AND MEASURES: Patients diagnosed with clinically localized prostate cancer were mailed a questionnaire consisting of new and previously validated quality of life items and ancillary scales. Data from returned questionnaires were analyzed and used to create a multiscale instrument that assesses the effects of treatment and disease on urinary, sexual, and bowel domains, supplemented by a scale assessing anxiety over disease course/effectiveness of treatment. The instrument was then mailed to a second sample of prostate cancer patients once and then again two weeks later to assess test retest reliability. To assess feasibility in clinical settings, the instrument was self-administered to a third patient sample during a urology clinic visit. RESULTS: All scales exhibited good internal consistency and test retest reliability, convergent and discriminant validity, and significant correlations with disease specific, generic health-related, and global measures of quality of life. Men with greater physiologic impairment reported more limitations in role activities and more bother. Scales were also able to differentiate patients undergoing different therapies. All scales exhibited negligible correlations with a measure of socially desirable responding. Additionally, the instrument proved feasible when used as a self-administered questionnaire in a clinical setting. CONCLUSIONS: The current instrument possesses brief multi-item scales that can be successfully self-administered in multiple settings. The instrument is flexible, relatively quick, psychometrically reliable and valid, and permits a more comprehensive assessment of patients' quality of life.

Aged↗
PubMed2000

Suicide gene therapy toxicity after multiple and repeat injections in patients with localized prostate cancer.

PURPOSE: We assess risks, toxicity and side effects of multiple and repeat in situ suicide gene therapy in patients with localized prostate cancer. MATERIALS AND METHODS: The study population comprised patients with localized prostate cancer receiving multiple and/or repeat intraprostatic injections of a replication deficient adenovirus containing the herpes simplex virus thymidine kinase (HSV-tk) gene. Intravenous ganciclovir or oral valaciclovir was given for 14 days after injection. Patients were recruited from 4 different clinical protocols in studies of toxicity and efficacy of suicide gene therapy, and closely monitored for toxicity and side effects during and after treatment. Toxicity was graded according to the Cancer Therapy Evaluation Program common toxicity criteria published by the National Cancer Institute. RESULTS: A total of 52 patients were treated under these clinical protocols with a total of 76 gene therapy cycles. Toxic events were recorded in 16 of 29 patients (55.2%) who were given multiple viral injections into the prostate, 7 of 20 (35%) who received 2 cycles of "suicide" gene therapy and 3 of 4 (75%) who received a third course of gene therapy. All toxic events after multiple or repeat injections were mild (grades 1 to 2) and resolved completely once the therapy course was terminated. No additive toxicity was noted in patients receiving repeat gene therapy cycles. Mean followup was 12.8 months (range 3 to 34). Preliminary results for 28 patients in 2 clinical protocols indicated a mean decrease of 44% in PSA in 43%. CONCLUSIONS: Direct injection into the prostate of a replication defective adenovirus containing the HSV-tk gene followed by intravenous ganciclovir is safe even in repeat cycles.

Acyclovir↗
PubMed2000

1999 American Urological Association Gallup Survey: changes in physician practice patterns, treatment of incontinence and bladder cancer, and impact of managed care.

PURPOSE: The Health Policy Survey and Research Committee of the American Urological Association and the Gallup Organization have performed a yearly survey of American urologists since 1992 to assess practice patterns. The results of the 1999 survey are presented. MATERIALS AND METHODS: A random sample of 503 urologists was interviewed in February and March 1999. Major content areas were physician practice patterns, the impact of managed care, and the treatment of pediatric patients, prostate cancer and benign prostatic hyperplasia, female incontinence and bladder cancer. RESULTS: The average urologist is 46.8 years old, certified by the American Board of Urology, sees 78 patients and performs 3.1 major surgical procedures weekly, refers moderate and complex pediatric procedures to specialists, and receives 40.6% of practice income from managed care. CONCLUSIONS: In an era when large group practices seem to be the norm remarkably 32% of urologists remain in solo practice. There has been a shift in where urologists spend their time, that is more in the office and less in the operating room. Minor and major open surgical procedures increased from 12.4 weekly to 16.4 and 2.9 to 3.1 in 1995 and 1999, respectively. Most urologists are comfortable treating straightforward pediatric problems such as cryptorchidism but refer more complex problems to pediatric urologists. Managed care represents an ever increasing proportion of urologist practice income, while office expenses continue to increase.

Adult↗
PubMed1999

1998 American Urological Association Gallup Survey: changes in physician practice patterns, treatment of ureteral stones and impact of managed care.

PURPOSE: The American Urological Association first commissioned the Gallup Organization to conduct a study to assess urologist practice patterns in 1992. We present the results of the seventh consecutive Gallup Survey performed for the Association. MATERIALS AND METHODS: A random sample of 537 American urologists who completed urological residency and practiced at least 20 hours weekly in 1997 were interviewed by telephone in March 1998. Major topic areas included general demographics, practice patterns, treatment of ureteral stones and experience with managed care. RESULTS: Demographic trends indicated a significant decrease in average urologist age from 49.4 years in 1992 to 46.8 in 1998. Of the urologists 99% reported that they treat ureteral stones. Managed care had an increasingly larger role in most practices, particularly in the western United States, where 73% of urologists reported that they contract with a Medicare health maintenance organization. CONCLUSIONS: The average age of practicing urologists significantly decreased, which may be due to an increasing number of urologists retiring at an earlier age, although this finding is not clear. Nearly all urologists treated ureteral stones with considerable consistency. Finally, managed care appeared to have a major impact on most urologists throughout the United States.

Adult↗
PubMed1999

Recall and attitudes in patients with prostate cancer.

OBJECTIVES: To assess the ability of men with adenocarcinoma of the prostate to recall aspects of testing leading to their diagnosis, recall of the informed consent process, and their satisfaction with treatment and that treatment's impact on their lives. METHODS: A Gallup Organization telephone survey of a national sample of 421 men with known prostate cancer randomly selected from a pool of men identified during "National Prostate Cancer Awareness Week" was performed from November 1995 to January 1996. Men were queried about diagnostic tests performed to make the diagnosis of prostate cancer, reasons for being "tested," sources of importance in helping men make an informed treatment decision, informed consent discussions, treatment satisfaction, treatment-related quality of life, and the quality of ongoing physicians' care. RESULTS: Patients' recall of procedures performed to diagnose prostate cancer is poor; less than 20% remember having a "biopsy." More than 80% depended entirely on their attending urologist for informed consent and education about prostate cancer management. Forty percent sustained a complication as a result of their treatment, primarily impacting their sexual or urinary function. Ongoing follow-up care provided by physicians was reported as poor in the management of sexual or urinary problems by 50% and 33% of patients, respectively. CONCLUSIONS: Patients are generally satisfied with the care process for prostate cancer. However, the lack of patient recall for diagnostic procedures makes the adequacy of the current informed consent process questionable and suggests the need for increased efforts at improving patient education.

Adenocarcinoma↗
PubMed1999

Sildenafil citrate after radical retropubic prostatectomy.

PURPOSE: Erectile dysfunction continues to be a significant problem for men after radical retropubic prostatectomy despite nerve sparing techniques. Sildenafil citrate (Viagra) has proved effective for erectile dysfunction in many men. We determine the efficacy of sildenafil in men with erectile dysfunction after radical retropubic prostatectomy and examine variables that may impact the response to treatment. MATERIALS AND METHODS: A total of 84 men were prescribed sildenafil after radical retropubic prostatectomy and asked to complete a series of questionnaires, including the International Index of Erectile Function (IIEF), on erectile function before and after sildenafil administration. The importance of factors, such as patient age, time since surgery, degree of cavernous nerve sparing, preoperative prostate specific antigen, Gleason score, clinical and pathological stage, and baseline postoperative erectile function, was examined. RESULTS: Of the 84 patients 45 (53%) had improved erections and 34 (40%) had improved ability for intercourse while taking sildenafil. Mean IIEF score for the erectile function domain increased from 9 to 14 (p <0.001). Orgasmic function (p = 0.004) and intercourse satisfaction (p = 0.009) also significantly improved. The degree of nerve sparing and baseline postoperative erectile dysfunction had a significant impact on the ability of sildenafil to improve erectile function (p = 0.010 and p <0.001, respectively) and total IIEF questionnaire responses (p = 0.031 and p <0.001, respectively). Age and pathological stage also appeared to have a significant effect. CONCLUSIONS: Sildenafil improved erectile function and the ability to have intercourse in more than half of men after radical retropubic prostatectomy. Baseline postoperative erectile function, which is dependent on the degree of nerve sparing technique, significantly impacts the likelihood that patients will respond to sildenafil.

Aged↗