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D W Cranston

Publications and source records attributed to D W Cranston.

At least 19 recordsLinked to original sources
PubMed2005

The safety and feasibility of extracorporeal high-intensity focused ultrasound (HIFU) for the treatment of liver and kidney tumours in a Western population.

High-intensity focused ultrasound (HIFU) provides a potential noninvasive alternative to conventional therapies. We report our preliminary experience from clinical trials designed to evaluate the safety and feasibility of a novel, extracorporeal HIFU device for the treatment of liver and kidney tumours in a Western population. The extracorporeal, ultrasound-guided Model-JC Tumor Therapy System (HAIFU Technology Company, China) has been used to treat 30 patients according to four trial protocols. Patients with hepatic or renal tumours underwent a single therapeutic HIFU session under general anaesthesia. Magnetic resonance imaging 12 days after treatment provided assessment of response. The patients were subdivided into those followed up with further imaging alone or those undergoing surgical resection of their tumours, which enabled both radiological and histological assessment. HIFU exposure resulted in discrete zones of ablation in 25 of 27 evaluable patients (93%). Ablation of liver tumours was achieved more consistently than for kidney tumours (100 vs 67%, assessed radiologically). The adverse event profile was favourable when compared to more invasive techniques. HIFU treatment of liver and kidney tumours in a Western population is both safe and feasible. These findings have significant implications for future noninvasive image-guided tumour ablation.

Adult↗
PubMed2002

Coding errors: a comparative analysis of hospital and prospectively collected departmental data.

OBJECTIVES: To assess the accuracy of a hospital coding database at a busy tertiary referral urological unit. METHODS: Prospectively collected departmental coding data for all urological patients attending the Churchill Hospital, Oxford between 1 May 1999 and 30 April 2000 were compared with the coding data entered by hospital coding clerks on the Oxford Radcliffe NHS Trust database. RESULTS: There were significant discrepancies between the number of patients on the hospital and the departmental database (639 vs 1109). There were gross procedural coding errors in 74 cases. CONCLUSION: Hospital-coded data in this study were incomplete and inaccurate. This has important implications when considering the validity of hospital-trust databases when used as a source for medical research, clinical audit and as a representation of a consultants' clinical workload.

Data Collection↗
PubMed2002

The urological complications of renal transplantation: a series of 1535 patients.

OBJECTIVE: To determine the incidence of urological complications of renal transplantation at one institution, and relate this to donor and recipient factors. PATIENTS AND METHODS: A consecutive series of 1535 renal transplants were audited, and a database of donor and recipient characteristics created for risk-factor analysis. An unstented Leadbetter-Politano anastomosis was the preferred method of ureteric reimplantation. RESULTS: There were 45 urinary leaks, 54 primary ureteric obstructions, nine cases of ureteric calculi, three bladder stones and 19 cases of bladder outlet obstruction at some time after transplantation. The overall incidence of urological complications was 9.2%, with that for urinary leak or primary ureteric obstruction being 6.5%. One graft was lost because of complications, and there were three deaths associated directly or indirectly with urological complications. There was no association with recipient age, cadaveric vs living-donor transplants, or cold ischaemic times before organ reimplantation, although the donor age was slightly higher in cases of urinary leak. There was no association with kidneys imported via the UK national organ-sharing scheme vs the use of local kidneys. The management of these complications is discussed. CONCLUSION: The incidence of urological complications in this series has remained essentially unchanged for 20 years. The causes of these complications and techniques for their prevention are discussed.

Adolescent↗
PubMed2000

Five-year data from the Oxford Laser Prostatectomy Trial.

OBJECTIVE: To evaluate the natural history of a group of patients who underwent contact laser prostatectomy or transurethral resection of the prostate (TURP). PATIENTS AND METHODS: Patients were followed up at 5 years after enrolling in a prospective double-blind randomized controlled trial of TURP vs contact laser prostatectomy. RESULTS: Of the initial trial patients, 11.5% had died (seven in the laser and 10 in the TURP arm) and eight (5.4%) were too incapacitated by coexistent medical disease to respond to the questionnaires. Thirty-eight patients were not available for follow-up, despite numerous invitations. Thirteen of the laser patients (18%) and 11 of the TURP patients (14.5%) had undergone re-operation. Two patients from each arm had received alpha-blockers for worsening symptoms. CONCLUSIONS: Five years after prostatic surgery, a significant number of patients were dead or disabled by coexistent medical disease. The re-operation rate after TURP and contact laser prostatectomy were similar.

Double-Blind Method↗
PubMed2000

Eukaryotic initiation factor-4E in superficial and muscle invasive bladder cancer and its correlation with vascular endothelial growth factor expression and tumour progression.

Vascular endothelial growth factor (VEGF) is an important factor mediating tumour angiogenesis. VEGF mRNA is differentially expressed in bladder cancer with high expression in superficial tumours (stage pTa and pT1) contrasting with low expression in muscle invasive tumours (stage > or = pT2). To investigate mechanisms regulating VEGF expression in bladder cancer, VEGF mRNA and protein were measured in normal bladder (n = 12) and primary bladder cancers (n = 57). VEGF protein levels correlated with mRNA expression in normal bladder (r = 0.68, P = 0.02) and bladder cancer (r = 0.46, P = 0.0007). Whilst VEGF mRNA expression was threefold higher in superficial compared to muscle invasive bladder cancers (P = 0.0001) there was no difference in VEGF protein (P = 0.81). Accordingly, the median protein:mRNA ratios increased more than 15-fold with increasing tumour stage (P < 0.0001) suggesting translational regulation. Expression of the eukaryotic initiation factor-4E (elF-4E), a factor implicated in the translational regulation of VEGF, was greater in tumours than normal bladder (P < 0.0001) and correlated with VEGE protein:mRNA ratios (n = 43, r = 0.54, P = 0.0004) pointing to its role in the regulation of VEGF. In superficial tumours (n = 37) high expression of eIF-4E was associated with a poor prognosis and reduced stage progression-free survival (P = 0.04, Cox proportional hazards model). The study demonstrates that eIF-4E may be involved in translational regulation of VEGF in bladder cancer and might have a role as a prognostic factor in bladder cancer.

Carcinoma, Transitional Cell↗
PubMed1997

Is day case surgery in urology associated with high admission rates?

The nature of the procedures and patients in urological day surgery may lead to high admission rates. A retrospective audit was performed over 8 years (1988 to 1996) to determine admission rates in a urological day surgical unit and examine reasons for and methods of decreasing admissions. The overall admission rate was 9.3%. Higher rates were associated with cystoscopic procedures, with 46% of admissions after bladder tumour cystosurveillance and a further 18% after urethroscopic surgery for urethral strictures. There was a surgical indication for admission in 72% of cases, with an anaesthetic indication in 17%. The study demonstrates that admission rates accompanying urological day surgery are higher than the 3% proposed by The Royal College of Surgeons of England. Achieving a rate of 3% may require restrictive patient selection that will deprive some patients the benefits associated with urological day surgical care.

Aged↗
PubMed1996

The Oxford Laser Prostate Trial: sensitivity to change of three measures of outcome.

OBJECTIVES: To evaluate the sensitivity to change of outcome measures in a double-blind randomized controlled trial of transurethral resection of the prostate (TURP) and contact laser prostatectomy. METHODS: A total of 152 patients were randomized to TURP or contact laser prostatectomy using the Surgical Laser Technology (SLT) system. Preoperative data were obtained using a self-administered questionnaire containing the American Urological Association (AUA-7) symptom score, the bothersome score (benign prostatic hyperplasia impact index), and the Short Form-36 health status questionnaire (SF-36). Follow-up was at 1 and 3 months. Effect size scores were calculated to indicate the extent of change from baseline to follow-up. RESULTS: Data were available on 148 patients: 72 received laser therapy and 76 received TURP. Mean change in AUA-7 score at 3 months was 7.3 in the laser arm, compared with 11.9 in the TURP arm (P < 0.05). Furthermore, substantial change was detected in both groups on the bothersome score. However, very few significant differences in SF-36 dimension scores from baseline to 3 months were detected. CONCLUSIONS: The SF-36 at both baseline and follow-up indicated a similar level of health status as that reported in the general population. Subsequently, the measure did not improve on any dimensions. Our data support the claim of some researchers that shorter disease-specific indices are vital to the evaluation of treatment regimens in clinical trials, especially when the general health of the patients is similar to that of the population.

Double-Blind Method↗
PubMed1996

The Oxford Laser Prostate Trial: economic issues surrounding contact laser prostatectomy.

OBJECTIVE: To compare the economic implications of transurethral resection of the prostate (TURP) and contact-laser vaporization of the prostate (with the SLT system) using data obtained from a randomized controlled trial. METHODS: All aspects of management before, during and after surgery on 102 patients, followed up for 3 months, were costed and analysed. Based on the data from the trial, the mean costs were calculated. A sensitivity analysis was then performed to examine the effect of changes in some of the relevant variables. The mean difference in cost between laser treatment and TURP was plotted against the cost of laser consumables, assuming a 5% re-operation rate for both operations at 5 years and a 5% discount rate. A range of laser re-operation rates was compared with the mean difference in costs, assuming a hospital stay of one night and two district-nurse visits. Other assumptions on discounts and re-operation rates, based on collected data, were also tested. RESULTS: TURP will remain more economical until the cost of laser consumables is reduced to 20% of the current list price, or a hospital stay of one night is introduced. CONCLUSIONS: The costs of contact-laser vaporization of the prostate are likely to exceed the costs of TURP unless laser treatment is accompanied by a more active approach to post-operative management, including a hospital stay of one night and, if necessary, the removal of the patient's catheter at home by a district nurse.

Costs and Cost Analysis↗
PubMed1996

The Oxford Laser Prostate Trial: a double-blind randomized controlled trial of contact vaporization of the prostate against transurethral resection; preliminary results.

OBJECTIVE: To compare the results of contact laser vaporization and transurethral resection of the prostate (TURP) in a double-blind randomized controlled clinical trial. PATIENTS AND METHODS: The study comprised 148 patients with clinical benign prostatic hypertrophy (BPH) who were recruited and allocated randomly to undergo either TURP (72 patients) or laser ablation of the prostate (76 patients). The outcome was assessed using the American Urological Association (AUA -7) symptom score after 1 and 3 months as the primary measure and by urinary flow rates, haematological factors and the duration of hospital stay and length of catheterization. RESULTS: With 90% statistical power, the results at 3 months showed no clinical or statistical difference between the treatments in change in AUA symptom score. A lower blood loss, hospital stay and duration of catheterization significantly favoured the laser treatment, although the failure rate of trial without catheter and the rate of re-operation were higher after laser treatment. CONCLUSIONS: These early data are encouraging for this technique, although the outcome after one year requires evaluation before advocating the widespread uptake of this method.

Aged↗
PubMed1996

The Oxford Laser Prostate Trial: sexual function data from a randomized controlled clinical trial of contact laser prostatectomy.

OBJECTIVE: To examine the effects of contact laser vaporization prostatectomy and transurethral resection of the prostate (TURP) on sexual function and to examine their association with treatment satisfaction. METHODS: Data on sexual function were collected pre-operatively and 3 months after contact laser vaporization prostatectomy or TURP. The sexual outcome was examined in relation to satisfaction with treatment and quality of life. RESULTS: A wide variation in sexual function was seen at baseline with overall 45% of the patients being impotent during the previous year and 49% claiming to not always have erections when stimulated 1 month prior to surgery. At 3 months postoperatively, 4% of the laser and 3% of the TURP patients who were previously potent were now impotent. There were no statistically significant associations between preoperative or postoperative (3 months) sexual function and either age, preoperative catheterization, or prostate volume. CONCLUSION: The impotence rate 1 month prior to surgery is higher than in previous reports, and the impotence rate after contact laser prostatectomy in this sample size is similar to that seen following TURP.

Aged↗