Biomedical subjects

M A Jewett

Publications and source records attributed to M A Jewett.

At least 19 recordsLinked to original sources

PubMed2003

Long-term followup of a randomized trial of 0 versus 3 months of neoadjuvant androgen ablation before radical prostatectomy.

PURPOSE: In 1992 we initiated a national randomized prospective trial of 3 months of cyproterone acetate before radical prostatectomy compared to prostatectomy alone. Initial results indicated a 50% decrease in the rate of positive surgical margins. This decrease did not translate into a difference in prostate specific antigen (PSA) progression at 3 years. This report is on the long-term outcome (median followup 6 years) of this cohort. MATERIALS AND METHODS: This prospective, randomized, open label trial compared 100 mg cyproterone acetate 3 times daily for 3 months before surgery to surgery alone. Randomization occurred between January 1993 and April 1994. Patients were stratified according to clinical stage, baseline serum PSA and Gleason sum. A total of 213 patients were accrued. Biochemical progression was defined as 2 consecutive detectable PSAs (greater than 0.2 ng/ml) at least 4 weeks apart, re-treatment or death from prostate cancer. RESULTS: A total of 34 (33.6%) patients undergoing surgery only and 42 (37.5%) patients given neoadjuvant hormone therapy (NHT) had biochemical recurrence during the median followup of 6 years. Despite the significant pathological down staging in this study, there was no significant difference in number of patients with no evidence of biochemical disease (bNED) survival (p = 0.732). A bNED survival benefit favoring NHT was seen in men with a baseline PSA greater than 20 (p = 0.015). CONCLUSIONS: After 6 years of followup there was no overall benefit with 3 months of NHT. Improved bNED survival was seen in the highest risk PSA group (PSA greater than 20). The possibility that high risk patients may benefit from NHT warrants further investigation.

Androgen Antagonists↗

PubMed2001

HPC2 variants and screen-detected prostate cancer.

Two studies have reported significant associations between susceptibility to prostate cancer and two common missense variants of the HPC2/ELAC2 gene, with estimated relative risks in the range of two- to threefold. We investigated whether these polymorphisms could be informative in the prediction of the presence of prostate cancer in men undergoing prostatic biopsy for the evaluation of an elevated serum-PSA level (> or = 4.0 ng/ml). We genotyped 944 men who underwent a prostate biopsy at our institution, as well as a control population of 922 healthy, unselected women from the same population. The prevalence of the HPC2 Ala541Thr allele was similar in men with prostate cancer (6.3%), men with other prostatic conditions (6.8%), and healthy women (6.3%) (P = .83). We conclude that HPC2 genotyping is unlikely to be a useful adjunct to PSA in the prediction of the presence of biopsy-detected prostate cancer in asymptomatic men.

Adenocarcinoma↗

PubMed2001

V89L polymorphism of type-2, 5-alpha reductase enzyme gene predicts prostate cancer presence and progression.

OBJECTIVES: The valine (V) to leucine (L) polymorphism of the SRD5A2 gene is associated with 5-alpha reductase-2 activity; patients with the V allele have high activity and patients with the L allele have low activity. We examined whether this polymorphism predicts the presence of prostate cancer in 320 men without cancer who underwent biopsy and cancer progression in 318 men who underwent radical prostatectomy. METHODS: The effect of the SRD5A2 gene in predicting the presence of prostate cancer was examined using logistic regression analysis, controlling for established risk factors. The effect of the SRD5A2 gene in predicting prostate cancer progression was examined using a nested, matched, case-control design. Most of the participants were white. RESULTS: Of the 320 men, 158 (49.4%) were found on biopsy to have prostate cancer. The overall distribution of the V/V, V/L, and L/L genotypes was 47.5%, 42.5%, and 10.0%, respectively. The adjusted odds ratio for having prostate cancer for patients with at least one V allele was 2.53 compared with patients with the L/L genotype (P = 0.03). Of the 318 patients with cancer, 80 had biochemically detected recurrence and 238 had no evidence of recurrence. The odds ratio for progression for patients with at least one V allele was 3.32 (95% confidence interval 1.67 to 6.62, P = 0.0006) compared with patients with the L/L genotype. CONCLUSIONS: Men who have the V allele of the SRD5A2 gene have a twofold increase in the risk of prostate cancer development and an additional twofold increase in the risk of progression compared with men with the L/L genotype.

Aged↗

PubMed2001

Allelic deletion fingerprinting of urine cell sediments in bladder cancer.

BACKGROUND: Bladder cancer shows frequent nonrandom allelic deletion at various chromosomal regions. Genotypic detection methods could potentially identify patients at risk for recurrent progressive disease. In this study, we examined allelic deletion at specific chromosomal loci in tumor tissue and urine cell sediment samples using a microsatellite-based protocol. Although both allelic deletion and microsatellite instability have been reported in primary bladder cancer, microsatellite instability was not specifically examined in this study. We report a pilot study of 40 patients with bladder cancer in which allelic deletion in tumor tissue and urine cell sediment was compared with conventional urine cytology results. METHODS AND RESULTS: Forty tumors were analyzed using a set of microsatellite primers from chromosomes 3, 4, 8, 11, 14, and 17 to construct allelic deletion fingerprints. Cy5.5-labeled PCR products were analyzed using the OpenGene System and GeneObjects software. Eighty-eight percent of tumors showed allelic deletion. In urine cell sediments, the tumor detection rate was 80% compared with 50% for routine urine cytology. The allelic deletion fingerprinting (ADF) procedure identified 69% of incipient tumors, cases initially classified as normal by routine urine cytology. CONCLUSION: ADF analysis provides a reliable noninvasive method for the detection and monitoring of recurrent cancer in urine cell sediment samples from patients with bladder cancer.

Adult↗

PubMed2001

Variation in enzymes of arylamine procarcinogen biotransformation among bladder cancer patients and control subjects.

Arylamines such as 2-naphthylamine and 4-aminobiphenyl are suspected human bladder procarcinogens that require bioactivation to DNA-reactive species to exert their carcinogenic potential. The goals of the present study were (i) to assay for the presence of the arylamine acetyltransferases NAT1 and NAT2, and of the cytochrome P450 isoform CYP1A2, in human bladder epithelium; and (ii) to determine whether the activities of these arylamine biotransforming enzymes differ between bladder cancer patients and control subjects. We measured in-vitro enzyme activities in biopsies of normal, undiseased bladder epithelium obtained from 103 bladder cancer patients. NAT1 activity was detectable in all samples, with mean levels higher than those found in human liver. Kinetic evidence also suggested low levels of NAT2 expression in this tissue, but there was no detectable CYP1A2 by either enzymatic or immunochemical measurements. We also compared several probe drug indices of in-vivo NAT1, NAT2 and CYP1A2 activity between 53 bladder cancer patients and 96 cancer-free control subjects who were carefully matched for age, gender and smoking status. NAT1 and NAT2 genotypes were also determined. No significant differences were found between bladder cancer patients and control subjects for a number of individual phenotypic or genotypic predictors of enzyme function. Our results suggest that although expression of particular arylamine biotransforming enzymes within the bladder tissue could play a significant role in locally bioactivating arylamine procarcinogens in theory, interindividual variations in CYP1A2, NAT1 and NAT2 activities do not significantly differ between bladder cancer patients and control subjects when potential arylamine exposures are controlled for

Acetyltransferases↗

PubMed2001

Development of a radiofrequency based thermal therapy technique in an in vivo porcine model for the treatment of small renal masses.

PURPOSE: Incidentally detected small renal tumors appear to grow slowly and be localized to the kidney. Minimally invasive therapies are being investigated as alternatives to standard surgical techniques. Radiofrequency ablation has been reported for the treatment of small renal cell carcinomas. We developed a radiofrequency technique and established its efficacy and safety in a large animal model. METHODS AND METHODS: A total of 22 lesions were created in normal kidneys of 7 pigs. Radiofrequency energy was administered during open exposure of the kidneys or percutaneously under ultrasound guidance. Lesion development was monitored with gray-scale and power Doppler ultrasound. To avoid heating surrounding tissues new hydro-dissection and gas-dissection techniques were developed. Lesion sizes and characteristics were assessed by ultrasound and pathological examination. RESULTS: No complications were observed due to probe insertion and removal. Perirenal structures were thermally damaged before the development and application of the dissection techniques. Lesion size was accurately predicted by gray-scale ultrasound on day 7. Loss of perfusion in the ablated volume was confirmed by power Doppler ultrasound. Lesions were wedge-shaped, presumably due to the effects of heating on segmental blood flow distribution. Pathological examination revealed changes consistent with thermal injury and ischemic type infarction. CONCLUSIONS: Radiofrequency thermal therapy is an effective and efficient method for ablating normal renal tissue in the pig. It may be applied percutaneously under ultrasound guidance with minimal complications provided that vital adjacent structures are protected from thermal damage. Further studies are required in humans before adopting this technique as definitive treatment for small renal cell carcinoma.

Animals↗

PubMed2000

Serum human glandular kallikrein-2 protease levels predict the presence of prostate cancer among men with elevated prostate-specific antigen.

PURPOSE: We hypothesize that serum human glandular kallikrein-2 (hK2) levels predict the presence of prostate cancer among men prescreened by prostate-specific antigen (PSA). PATIENTS AND METHODS: We conducted a cross-sectional study of 324 men who had no history of prostate cancer and who were referred for prostate biopsy. PSA and hK2 levels were measured using specific nonisotopic immunometric techniques. Cases were patients who were diagnosed with adenocarcinoma of the prostate from biopsy, and controls were patients who had no evidence of cancer from biopsy. The odds ratio for detection of prostate cancer was determined for hK2 measurements, controlling for age, total-PSA level, digital rectal examination, and symptoms of urinary obstruction. RESULTS: Of 324 men, 159 (49.1%) had cancer. Mean hK2 levels and hK2:free-PSA ratios were significantly higher in cases than in controls (1.18 v 0.53 ng/mL, respectively, for hK2, P =.0001; 1.17 v 0.62 for hK2:free-PSA ratio, P =.0001). The crude odds ratio for prostate cancer detection for patients in the highest quartile of hK2 level was 5.83 (95% confidence interval [CI], 2.8 to 12.1; P =.0001) compared with patients in the lowest quartile. The adjusted odds ratio was 6.72 (95% CI, 2.9 to 15.6; P =.0001). Similarly, the crude and adjusted odds ratios for prostate cancer detection using the hK2:free-PSA ratio were 7.36 (95% CI, 3.6 to 15.1; P =.0001) and 8.06 (95% CI, 3. 7 to 17.4; P =.0001), respectively. These odds ratios were higher than that observed for prostate cancer detection by total-PSA level (2.73; P =.03). CONCLUSION: Among men prescreened with PSA for prostate cancer, patients with high hK2 measurements have a five- to eight-fold increase in risk for prostate cancer, adjusting for PSA level and other established risk factors. hK2 measurements may be a useful adjunct to PSA in improving patient selection for prostate biopsy.

Humans↗

PubMed2000

Variation in clinical outcome following shock wave lithotripsy.

PURPOSE: We measure and compare operator specific success rates of extracorporeal shock wave lithotripsy (ESWL) performed by 12 urologists in 1 unit to determine interoperator variation. MATERIALS AND METHODS: From January 1, 1994 to September 1, 1997 a total of 5,769 renal and ureteral stones received 9,607 ESWL treatments by 15 urologists with a Dornier MFL 5000 lithotriptor. The 3-month followup data are available for 4,409 stones. Outcome measures consisted of patient demographics, stone characteristics, technical details of lithotripsy, and stone-free and success rates by treating urologists. RESULTS: Treatment results were analyzed for 12 urologists (surgeons A to L) who treated more than 100 stones each, totaling 4,244 with followup information available. Mean stone-free and success rates were 50.6% and 72.3%, respectively. Surgeon A had significantly higher stone-free and success rates of 56.2% and 76.7%, respectively (p<0.05), with treatment results from 877 stones, which was a significantly higher number than others (p<0.05). Significant differences existed in mean number of shocks delivered among urologists (p = 0.0001), with surgeons A and J delivering the highest mean numbers (2,317 and 2,801, respectively). There was no difference in treatment duration (p = 0.75) but variation existed among urologists in terms of mean maximum treatment voltage (p = 0.0001). Mean fluoroscopy time at 4.1 minutes was higher for surgeon A than others (p<0.05). Mean complication rate following ESWL was 4.9% with no difference among urologists (p = 0.175). Re-treatment was required in 21.7% of cases and surgeon A had the lowest rate (15.9%, p<0.05). CONCLUSIONS: We demonstrated clinically and statistically significant intra-institutional differences in success rates following ESWL. The best results were obtained by the urologist who treated the greatest number of patients, used a high number of shocks and had the longest fluoroscopy time. Accurate targeting is crucial when using a lithotriptor, such as the Dornier MFL 5000, with a narrow focal zone of 6.5 mm. in diameter. Other centers should be encouraged to develop similar programs of outcome analysis in an attempt to improve performance.

Adolescent↗

PubMed2000

Comparison of molecular and conventional strategies for followup of superficial bladder cancer using decision analysis.

PURPOSE: Patients with superficial bladder cancer require long-term surveillance for recurrence. We compared the cost of cystoscopy and cytology (standard care) to that of urinary markers (modified care) for patients with a history of superficial bladder cancer. MATERIALS AND METHODS: We constructed a decision analysis model that compared the 2 strategies for a hypothetical followup interval of 3 years. Probabilities required for the decision tree were based on a cohort of 361 patients diagnosed with superficial bladder cancer from 1987 to 1997. Sensitivity analyses were used to determine whether test sensitivity and specificity would affect cost thresholds. Costs for each strategy were then applied to actual practice patterns. RESULTS: The cost of modified care ranged from $158 to $228 for each followup visit when using a urinary marker with a sensitivity and specificity of 95% and 77%, respectively. The cost of standard care was $240 for each followup visit. Based on sensitivity analyses the probability of disease recurrence and urinary marker accuracy were important determinants of expected costs. Mean number of followup assessments for patients followed more than 3 years was 4.3, 2.2 and 1.5 for years 1, 2 and 3, respectively. Cumulative costs of modified care were lower than those of standard care. CONCLUSIONS: Urinary marker testing for followup of patients with superficial bladder cancer is less expensive than the standard method of cystoscopy and urinary cytology based on our model. Future studies will be required to consider other factors that could affect the cost advantage of urinary markers, including indirect costs, the psychosocial impact of testing and different surveillance frequencies.

Decision Support Techniques↗

PubMed2000

Significance of the CAG repeat polymorphism of the androgen receptor gene in prostate cancer progression.

PURPOSE: The CAG repeat polymorphism of the androgen receptor gene has been associated with an increased prostate cancer risk, and the repeat length correlated with cancer stage and grade at presentation. Men with an allele length of </= 18 CAG repeats have a 2-fold increase in risk for high-stage or high-grade prostate cancer, compared with patients with a longer CAG repeat. We examined the significance of the CAG repeat polymorphism of the androgen receptor gene for predicting prostate cancer progression among 318 patients treated by radical prostatectomy for clinically localized prostate cancer between 1987 and 1994. MATERIALS AND METHODS: Leukocyte DNA was collected and genotyping of the CAG repeat polymorphism was performed using a PCR-based direct sequencing method. Risk ratios were calculated for developing biochemical recurrence for patients associated with an allele length of </= 18 CAG repeats, compared with patients with an allele length of >18 CAG repeats, controlling for grade, stage and serum PSA level at diagnosis using Cox proportional hazard modeling. RESULTS: Overall, the CAG repeat allele was not predictive of recurrence; tumor grade, stage and PSA level at diagnosis were the only predictors of recurrence in a multivariate analysis. However, for patients at low risk for recurrence (Gleason score 2 to 6, stage pT2, and PSA </= 10 ng./ml.), the relative risk of recurrence associated with an allele of </= 18 CAG repeats was 8.07 (95% C.I., 2.02 to 32.2, p = 0.004), compared with patients with an allele length of >18 CAG repeats. In contrast, for patients at high risk of recurrence (Gleason score >/= 7, stage pT3/4, or PSA >10 ng./ml.), the relative risk associated with the </= 18 CAG repeat allele was 0.72 (95% C.I., 0.33 to 1.57, p = 0.41), compared with patients with the >18 CAG repeat allele. CONCLUSIONS: The length of the CAG repeat polymorphism of the androgen receptor gene may be important for prostate cancer recurrence among patients who are otherwise at low risk for recurrence after radical prostatectomy. These findings have potential implications for patient selection for adjuvant treatment, and for the development of novel treatments.

Alleles↗

PubMed2000

The natural history of small renal masses.

PURPOSE: Ultrasound, computerized tomography and magnetic resonance imaging are widely available. Incidentally discovered small renal masses are reported more frequently. Most of these masses are low stage renal cell carcinomas. To understand better the natural history of these lesions and offer appropriate management, we followed prospectively a series of patients with this type of lesion. MATERIALS AND METHODS: A total of 13 patients with radiologically detected solitary small renal masses who were unfit for or refused surgery were followed with abdominal imaging for a median of 42 months. Median patient age was 69 years and mean lesion volume at diagnosis was 13.6 cm.3 or 2.95 cm. in diameter. Growth rate was calculated based on tumor volume rather than bi-dimensional diameter. Individual slopes of tumor size in time were calculated. RESULTS: Of the 13 patients 5 underwent surgery following a period of surveillance because of apparent tumor enlargement or new onset of symptoms. Pathological evaluation revealed renal cell carcinoma in all 5. No patient had metastases. Only 2 tumors were fast growing and these were the only 2 cases in which symptoms developed. When these patients were excluded from analysis, average growth rate was 1.32 cm.3 per year (p = 0.5, 95% confidence interval -3.00 to 5.76 cm.3 per year), which was not statistically significantly different from 0 slope or no growth. CONCLUSIONS: These results demonstrate that the growth rate of small renal tumors is variable, tumors that are destined to grow and possibly metastasize do so early and most small tumors grow at a low rate or not at all.

Aged↗

PubMed2000

Higher urinary potassium is associated with decreased stone growth after shock wave lithotripsy.

PURPOSE: We correlated serum and urinary biochemical parameters with radiological evidence of stone growth after shock wave lithotripsy. MATERIALS AND METHODS: Biochemical parameters in serum and 24-hour urine collections of 359 patients were correlated with stone growth for 2 years after shock wave lithotripsy. Each patient underwent a minimum of 2 radiological studies at 3 and 12 months and plain abdominal x-ray at 24 months. The presence and size of stones were documented by a radiologist in blinded fashion. Stone growth was defined as measurable growth of a preexisting stone or new stone formation. RESULTS: A total of 209 patients remained stone-free or had no existing stone growth, while stone size decreased in 30. Of the remaining 120 patients with stone growth 72 had new growth and 48 had growth of preexisting stones. Urinary excretion of potassium was significantly higher in those without than with stone growth (mean 24-hour urine collection plus or minus standard deviation 62 +/- 27 versus 54 +/- 23 mmol., p = 0.009). The only parameter significantly associated with stone growth was urinary potassium. Linear regression revealed that for each 10 unit increase in urinary potassium there was a corresponding 2 mm. decrease in stone growth (p = 0.013). CONCLUSIONS: Our results indicate that increased urinary potassium excretion correlates with a decreased risk of stone growth up to 2 years after shock wave lithotripsy, implying that a high potassium diet may be beneficial for preventing stone growth. The effect of potassium supplementation on stone formation and growth must be investigated further.

Dietary Supplements↗

PubMed2000

Long term outcome and cost in the management of stage I testicular seminoma.

PURPOSE: To validate the use of surveillance as an alternative to adjuvant RT in clinical stage I seminoma, we analyzed our experience with the two approaches in terms of long term outcome and cost. PATIENTS AND METHODS: Between January 1981 and December 1994, 471 patients with stage I testicular seminoma were treated at our institution. Of these, 245 patients received post-operative RT (25 Gy) to the retroperitoneal lymph nodes, and 226 have been managed with surveillance following orchidectomy. Two patients were included in this series twice; both had RT previously for seminoma, were placed on surveillance for a contralateral seminoma and were analyzed for outcome of both primary tumors. The costs associated with both approaches were estimated in 1994 Canadian dollars (C$). RESULTS: With a median follow-up of 7.7 years in the surveillance patients, and 9.7 years in the adjuvant RT cohort, the 5 year actuarial survival for all patients was 97% and the cause-specific survival (CSS) was 99.8%. Of the 226 patients on surveillance 37 patients have relapsed to date; five of those developed a second relapse. One patient has died of disease. Of the 245 patients treated with adjuvant RT, 14 patients have relapsed and none had a second relapse. The CSS was 100%. Thirteen patients on surveillance (5.7%) and 10 patients treated with post-operative RT (4.1%) have received chemotherapy as part of their management. One hundred and eighty-nine patients on surveillance have received no post-orchidectomy treatment to date. Surveillance was more expensive with an average additional cost per patient per year of Can$2620 over 10 years. CONCLUSIONS: Both adjuvant RT and surveillance give excellent results in stage I seminoma. The documented increased risk of second malignant tumors following RT must be taken into account when considering the additional cost of surveillance. The routine use of post-operative RT in stage I seminoma should be reconsidered and a surveillance program offered to all patients as an alternative management option.

Actuarial Analysis↗

PubMed1999

Neoadjuvant hormonal therapy in carcinoma of the prostate.

The rising incidence of and mortality from prostate cancer has generated great interest in improving the results of current methods of treatment. It is well-established that large tumour volumes and positive surgical margins are correlated with higher rates of local failure and distant metastasis. Significant decreases in both tumour volume and the rates of positive surgical margins are seen with NHT. Follow-up data from one randomized trial of hormonal therapy before RT have shown significantly improved disease-free survival, but so far there has been no benefit in overall survival. However, the addition of adjuvant hormonal therapy has been reported to improve survival. The results suggest that neoadjuvant and adjuvant hormonal therapy may be a viable option in men with locally advanced prostate cancer in whom cure is probably impossible, but disease progression can potentially be slowed. What remains to be determined is whether hormonal therapy alone can produce the same results. For younger men with clinically localized prostate cancer, radical prostatectomy is increasingly the treatment of choice. Prospective randomized trials of NHT have produced impressive statistics for decreasing the incidence of positive surgical margins, but the potential to down-stage tumours remains controversial. Follow-up serum PSA measurements have thus far shown no benefit from neoadjuvant therapy. The possibility that patients who fail biochemically, whether they are from the pretreated or control group, may simply represent a subgroup with aggressive tumours that may not respond to androgen withdrawal, has yet to be proved. As more follow-up data are analysed within the next several years, there must be a clear survival advantage if NHT is to be offered as a treatment option. Despite the potential of neoadjuvant therapy, the use of androgen withdrawal before definitive surgical treatment should be limited to clinical trials until a clearer picture emerges. Some may argue that although there is no evidence of a true advantage for NHT, neither is there evidence of harm. However, it must be recognized that androgen withdrawal therapy has side-effects and adds significantly to the overall cost of treatment. Furthermore, NHT delays definitive treatment; clearly, this can be a source of anxiety for the patient and the impact on survival is unknown. Currently, the rates of pathologically organ-confined disease are high in some subsets of patients (e.g. low-stage, low-grade and low PSA) so that NHT is unlikely to have great additional benefit. Although the influence of hormones on prostate growth has been known for many decades, we are only now elucidating the biological mechanisms of hormonal therapy. Although androgen ablation therapy has been used in men with metastatic prostate cancer for more than 50 years, further research at the cellular and molecular level is essential if we are to refine treatment modalities for both localized and advanced disease. Furthermore, until we have more follow-up data from randomized clinical trials of NHT, it cannot be considered part of the standard treatment for carcinoma of the prostate. There are still too many unknown factors; only time will tell if the initial promise of NHT will be fulfilled.

Antineoplastic Agents, Hormonal↗

PubMed1999

Role for retroperitoneal lymphadenectomy for testis cancer.

There continue to be several controversies surrounding the role for retroperitoneal lymphadenectomy (RPL) in the management of patients with germ cell cancer of the testis. The initial treatment options for those with clinical stage I disease are surveillance (orchiectomy only), RPL or chemotherapy. Survival rates are similar with RPL and surveillance. Surgical morbidity has been reduced as techniques for RPL continue to improve. The likelihood of early or late (> 2 years) recurrence in the retroperitoneum is almost eliminated by RPL. Fewer follow-up computerized tomography scans of the abdomen are required and there are opportunities to reduce the duration and methods of follow-up, compared with surveillance. For patients with stage II disease, chemotherapy and RPL are equally effective initial treatment options but many patients require a combined approach. Initial RPL should be reserved for patients with smaller volume disease and possibly with lower preoperative marker levels. With RPL, patients are accurately staged and cured most of the time without double treatment. Approximately 30% of those with larger masses will have residual disease after initial chemotherapy and will require RPL as a second treatment. The third indication for RPL is to excise residual retroperitoneal masses following primary chemotherapy. Models to predict the presence of residual viable tumor, rather than necrosis only, at the time of surgery have been developed. If the orchiectomy specimen contained no teratoma, the tumor markers normalize after three or four courses of chemotherapy, and if the residual mass on computerized tomography scan is less than 2 cm in diameter, the rate of viable tumor may be low enough to omit RPL. In this way, the greater morbidity often associated with post-chemotherapy RPL may be avoided.

Humans↗

PubMed1999

The urology work force in Ontario for the 21st century: feast or famine?

OBJECTIVE: To address the issues of work-force planning and modelling in the 21st century for the specialty of urology in the Province of Ontario. DESIGN: Data (from 1991 to 1995) regarding urology physician resources were gathered from Health Canada, the Royal College of Physicians and Surgeons of Canada, the Ontario Physician Human Resources Data Centre, the Canadian Post-M.D. Education Registry, the System for Health Area Resource Planning (SHARP) database, the Canadian Institute for Health Information and the National Physician Database. Specifically, the age and gender breakdown of currently active Ontario urologists, measures of urologist clinical activity (from Ontario Hospital Insurance Plan billings and questionnaires), inputs into and exits from the active urologist population were gathered, and estimates of future needs for urologist services, based on current population and demographic models, were made. A model to predict the balance between future needs for urology services and future supply of urologists was then created and validated against data drawn from the SHARP database. RESULTS: The model revealed that there will be a significant shortage of urologists in Ontario in the immediate and long-term future; by the year 2010 there will be a shortfall of 101 urologists in Ontario, or 51% of the total needed. CONCLUSIONS: Enlarging the urology training programs in Ontario would help to minimize the estimated shortfall. Systematic modelling of physician work-force needs for the future is necessary for the optimal allocation of health care resources. The methodology of the urology work-force model is generalizable to physician work-force planning for other specialty groups on a provincial or national basis.

Computer Simulation↗

PubMed1999

Progression detection of stage I nonseminomatous testis cancer on surveillance: implications for the followup protocol.

PURPOSE: To optimize followup in patients with stage I nonseminomatous testis cancer on surveillance we evaluated the contribution of each followup modality to the detection of progression as well as morbidity and mortality outcomes. MATERIALS AND METHODS: After orchiectomy 170 patients with clinical stage I nonseminoma were prospectively placed on a surveillance protocol. History, physical examination, serum tumor markers, abdominal and pelvic computerized tomography (CT), and chest x-ray were used for followup. The number of failures, methods and timing of progression detection, treatments required, mortality rate and subsequent contralateral primary tumors were recorded. RESULTS: The 170 surveillance patients were followed a median of 6.3 years. Within 2 years (median 6.9 months) postoperatively 48 patients (28.2%) had disease progression. History, physical examination, markers, CT and chest radiography provided the initial evidence of progression in 18 (37.5%), 34 (70.8%), 34 (70.8%), and 4 (8.3%) patients, respectively. Each modality was the only indicator of failure in 2 (4.2%), 4 (8.3%), 10 (20.8%) and 0 cases, respectively. Of the 170 patients 122 (71.8%) required no additional treatment beyond orchiectomy, 26 (15.3%) received 1 and 22 (12.9%) underwent more than 1 therapeutic modality. Only 1 patient (0.6%) died of disease. Contralateral tumors developed in 5 cases (2.9%) therapeutic a mean of 8.1 years after orchiectomy. CONCLUSIONS: In stage I nonseminoma patients, surveillance history, physical examination, tumor markers and abdominopelvic CT are necessary components of the followup protocol. Removal of routine chest x-ray from the protocol would not have changed progression detection. The initial surveillance visit must occur by 2 months postoperatively. Patients should be followed beyond 5 years and likely for life in addition to regular patient self-examination.

Adolescent↗

PubMed1999

Electromotive drug administration of lidocaine as an alternative anesthesia for transurethral surgery.

PURPOSE: A multicenter study was undertaken to evaluate the safety, efficacy and cost of electromotive drug administration of intravesical lidocaine to produce bladder local anesthesia as an alternative to traditional methods of spinal or general anesthesia. MATERIALS AND METHODS: A total of 94 patients were enrolled in the study who had either a history of bladder tumor that required cold cup bladder biopsy with fulguration for possible recurrence as a comparison trial, a bladder tumor treated with transurethral resection/fulguration or benign prostatic hyperplasia/carcinoma treated with transurethral resection. Pain scores using a Verbal Rating Scale were recorded for each individual biopsy, fulguration and resection event. Data for direct and indirect costs were collected using a standardized form for each patient to capture the details of the procedure, including times, drugs and disposables for each patient. RESULTS: There was a significant reduction in pain for patients who received electromotive intravesical lidocaine compared to no anesthesia for biopsy (p<0.03). Similarly, electromotive intravesical lidocaine for bladder biopsy and transurethral bladder tumor resection/fulguration was associated with higher patient satisfaction compared to previous treatments (p<0.00002). In contrast, electromotive intravesical lidocaine was insufficient for 3 of 6 transurethral prostatic resections. The cost per patient was about $146 Cdn less with electromotive intravesical lidocaine than with conventional general/spinal anesthesia. CONCLUSIONS: Electromotive intravesical lidocaine may be a safe, effective and affordable form of anesthesia for the ambulatory care of patients requiring transurethral bladder biopsy, resection or fulguration with a potential for cost savings.

Aged↗