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David C Miller

Publications and source records attributed to David C Miller.

At least 37 records · Page 2Linked to original sources
PubMed2006

Partial nephrectomy for small renal masses: an emerging quality of care concern?

PURPOSE: The recent popularization of laparoscopic radical nephrectomy may beget underuse of partial nephrectomy. To evaluate this concern we used the SEER registry to characterize national practice patterns for the surgical management of small renal masses. MATERIALS AND METHODS: Between 1988 and 2001, 14,647 patients with primary tumor size 7 cm or less were treated surgically for locoregional kidney cancer. The proportion of patients treated with PN was determined and stratified by year of diagnosis and tumor size. Multivariate models were developed to identify independent determinants of PN use and overall survival following surgical treatment of kidney cancer. RESULTS: Overall 1,401 patients (9.6%) were treated with PN vs 13,246 (90.4%) who underwent total nephrectomy. For tumors 7 cm or less, the use of PN increased progressively between 1988 (4.6%) and 2001 (17.6%, p < 0.001). Despite this trend PN remained fairly uncommon even for the smallest renal masses. Among patients with tumors less than 2 cm, 14% underwent PN in 1988 to 1989 vs 42% in 2000 to 2001. For tumors 2 to 4 cm the corresponding proportions were 5% and 20%, respectively (p < 0.001). Younger patient age, smaller tumor size and more recent diagnostic year were independent determinants of PN use (all p values < 0.05). All cause mortality was similar for patients treated with PN vs TN (HR 0.9, 95% CI 0.8-1.1). CONCLUSIONS: Despite more frequent application during the last 2 decades, nationwide use of PN remains relatively uncommon, even for the smallest renal masses. Recognizing the favorable outcomes associated with preservation of renal parenchyma, our findings identify a possible quality of care concern that should be addressed by the urological community.

Aged↗
PubMed2005

Long-term outcomes among localized prostate cancer survivors: health-related quality-of-life changes after radical prostatectomy, external radiation, and brachytherapy.

PURPOSE: We sought to elucidate long-term changes in health-related quality-of-life (HRQOL) outcomes by prospectively re-evaluating a well-characterized cohort of prostate cancer (PC) survivors 4 to 8 years after primary treatment. PATIENTS AND METHODS: Patients who had been evaluated previously at a median of 2.6 years after radical prostatectomy (RP), external radiation (three-dimensional conformal radiation therapy [3-D CRT]), or brachytherapy (BT) were recontacted at a median of 6.2 years after treatment. The clinical relevance of long-term HRQOL impairment among survivors was established by comparison with controls of similar age. Factors associated with HRQOL changes during this interval were evaluated. RESULTS: Of the 964 eligible men, 709 (73.5%) completed measurable questionnaires. In four domains (urinary irritative-obstructive, urinary incontinence, bowel, and sexual), significant HRQOL differences were detected for at least one of the therapy groups, compared with controls (all P < .05). During the 4-year interval, significant improvement was observed for the urinary irritative-obstructive (P < .0001) and bowel (P < .0001) domains among BT patients, whereas urinary incontinence HRQOL worsened for both the BT (P = .0017) and 3-D CRT (P = .0008) treatment groups. Overall sexual HRQOL deteriorated for the 3-D CRT cohort (P = .0017), as well as for controls (P = .0136). Among RP patients, significant HRQOL changes were not observed. CONCLUSION: During a 4-year interval from earlier to longer-term phases of PC treatment survivorship, sexual, urinary, and bowel dysfunction remain significant concerns among early-stage PC treatment survivors, compared with control men. Although postprostatectomy HRQOL remains relatively stable during this interval, disease-specific HRQOL continues to evolve among men treated with BT and 3-D CRT.

Aged↗
PubMed2005

Measuring the quality of care for localized prostate cancer.

PURPOSE: We describe the current status of quality of care measurement for localized prostate cancer and provide a framework for preserving a leadership role for our specialty in this dynamic and controversial field. MATERIALS AND METHODS: Basic methodological principles of quality of care assessment were reviewed. Several factors that suggest the potential for current variation in the quality of care for patients with localized prostate cancer, particularly those receiving active treatment, were then analyzed. Subsequently contemporary publications and investigations that comprise the current foundation of prostate cancer quality of care research were reviewed. RESULTS: The foundation for much of the emerging research in prostate cancer quality of care assessment is based on the Donabedian structure-process-outcome paradigm. The RAND candidate quality indicators for localized prostate cancer were developed in this framework and they represent the first effort to systematically consider the measurement of quality as it relates to prostate cancer. The feasibility of applying the RAND quality indicators to clinical quality of care assessments has been demonstrated, although further modification and refinement of the indicator set are necessary prior to large-scale, population based implementation of these quality assessment measures. Moreover, future quality of care efforts must make the transition to primarily prospective or concurrent quality assessments, such that measures can be taken to modify the structure and/or process of care at the time of delivery or shortly thereafter. CONCLUSIONS: Prostate cancer quality of care assessment represents a burgeoning domain of urological health services research. To date such initiatives have come from within and outside of our specialty. In the future such efforts are likely to expand and they may have a substantial impact on the clinical and administrative aspects of urological practice. As a result, urologists should maintain a leading role in efforts to further define of quality of care as it relates to prostate cancer and radical prostatectomy.

Humans↗
PubMed2005

The regionalization of radical cystectomy to specific medical centers.

PURPOSE: Regionalization of high risk surgical procedures to larger teaching hospitals has been suggested as a means to improve the quality of care. We established a novel framework for characterizing regionalization, implemented it to determine the extent to which regionalization of radical cystectomy has occurred and delineated whether specific patient characteristics are associated with this phenomenon. MATERIALS AND METHODS: We used the Nationwide Inpatient Sample to identify 22,088 patients who underwent radical cystectomy for bladder cancer from 1988 to 2000. Regionalization was assessed using 5 structural hospital measures, including teaching status, urban location, discharge volume, cystectomy volume and bed capacity. Adjusted models were developed to identify the significance of temporal trends and assess the association of demographic factors with structural qualities. RESULTS: Compared with 1988 to 1990 subjects were more likely to undergo cystectomy at teaching hospitals (OR 1.8), high cystectomy volume hospitals (OR 1.2), high discharge volume hospitals (OR 1.7) and large bed capacity medical centers (OR 1.4) in 1998 to 2000. The concentration of cystectomy to urban medical centers during the study years was 90% to 92%. The proportion of subjects undergoing partial cystectomy decreased from 23.9% to 16.6% as regionalization occurred. Older subjects were less likely to be treated at these regionalized centers. CONCLUSIONS: Without broad legislation from health care payers radical cystectomy has increasingly regionalized to specific medical centers. Despite this regionalization disparities in its use exist among specific, vulnerable patients. Addressing this may facilitate further concentration of this procedure.

Aged↗
PubMed2005

Identifying risk factors for potentially avoidable complications following radical cystectomy.

PURPOSE: Morbidity after radical cystectomy is common and associated with increased health care resource use. Accurate characterization of complications after cystectomy, associated patient specific risk factors, and perioperative processes of care are essential to directing changes in perioperative management that will reduce morbidity and improve the quality of patient care. MATERIALS AND METHODS: The National Surgical Quality Improvement Program (NSQIP) is a prospective quality management initiative of 123 Veterans Affairs Medical Centers nationwide. The NSQIP collects clinical information, intraoperative data and outcomes on a wide variety of surgical procedures from multiple surgical disciplines. Since 1991, 2,538 radical cystectomy procedures have been captured by the NSQIP. Modeling using logistic regression was performed to identify patient specific risk factors and perioperative process measures associated with postoperative morbidity. RESULTS: Of the 2,538 subjects at least 1 postoperative complication developed in 774 (30.5%). The most frequent complication was ileus (10%). Several factors were associated with the development of a complication, including age, dependent functional status, preoperative dyspnea, preoperative acute renal failure, chronic steroid use, preoperative alcohol consumption, American Society of Anesthesiology score, use of general anesthetic, operative time, intraoperative blood requirement and surgeon level of training. CONCLUSIONS: Morbidity remains high after cystectomy with 30.5% of subjects experiencing at least 1 complication. Measurable patient specific risk factors and perioperative processes associated with postoperative morbidity following cystectomy are now delineated which allows for improved risk stratification, patient counseling, and the development of novel processes that may incrementally reduce risk and improve outcomes.

Acute Kidney Injury↗
PubMed2004

Acute renal colic.

Explore the source record for details and available documents.

Acute Disease↗
PubMed2004

The effect that mutations in the conserved capsular polysaccharide biosynthesis genes cpsA, cpsB, and cpsD have on virulence of Streptococcus pneumoniae.

Four genes, cpsA-cpsD, at the 5' end of the capsular polysaccharide (CPS) biosynthesis locus are conserved in nearly all of the 90 known serotypes of Streptococcus pneumoniae. In the present study, the impact that mutations in cpsA, cpsB, and cpsD have on CPS production and on virulence in mice infected via systemic and intranasal routes was investigated. Strains exhibiting rough colony morphologies (in which either the cpsB or cpsD gene had been deleted) were avirulent, but a smooth, partially encapsulated strain (in which the cpsA gene had been deleted) was as virulent as the wild-type strain. Interestingly, mucoid strains containing mutations affecting the [YGX](3)-repeat domain of CpsD were unable to cause bacteremia after intranasal challenge of CD1 mice, even though such strains were capable of killing BALB/c mice after intraperitoneal challenge. In our model, the ability of S. pneumoniae to regulate, via CpsD phosphorylation, CPS production was required for its transition from the lung to the bloodstream.

Animals↗
PubMed2004

Impact of surgical volume on mortality and length of stay after nephrectomy.

OBJECTIVES: To evaluate the volume-outcome relationship in patients undergoing nephrectomy for neoplastic disease by examining the impact of the number of cases performed on in-hospital mortality and length of stay. Surgical volume is associated with postoperative mortality for many complex procedures; however, this relationship has not been characterized for patients undergoing nephrectomy for neoplastic disease. METHODS: Using the Nationwide Inpatient Sample database, 20,765 patients who underwent nephrectomy for neoplasm from 1993 through 1997 were identified by International Classification of Disease, Ninth Revision codes. Cases were stratified into volume groups on the basis of annual nephrectomy rates: low-volume hospitals performed 1 to 14 nephrectomies per year, medium-volume hospitals performed 15 to 33 per year, and high-volume hospitals performed more than 33 per year. Unadjusted and risk-adjusted analyses were performed. RESULTS: Overall mortality was 1.39%. Mortality declined as surgical volume increased. The mortality rate for low-volume hospitals was 1.60% versus 1.49% for medium-volume hospitals and 1.04% for high-volume hospitals (P = 0.017). After adjusting for case mix, high-volume hospitals had a 32% lower risk of in-hospital mortality than medium-volume hospitals (P = 0.029) and a 25% lower risk than low-volume hospitals (P = 0.094). Length of stay was not affected by hospital volume. Other independent risk factors for in-hospital mortality included age older than 65 years, chronic pulmonary disease, metastatic disease, and the urgent nature of the admission. CONCLUSIONS: A greater surgical volume, age younger than 65 years, elective conditions, and less comorbidity are associated with a significantly decreased risk of in-hospital mortality after nephrectomy. These findings provide compelling evidence that hospital volume and patient characteristics have important effects on surgical outcome specific to renal neoplasms.

Age Factors↗
PubMed2004

Aggressive treatment for bladder cancer is associated with improved overall survival among patients 80 years old or older.

OBJECTIVES: To examine the impact of various treatment modalities on survival among patients with bladder cancer who were 80 years old or older compared with younger patients. A compendium of evidence suggests that bladder cancer surgery is safe among octogenarians; however, the benefit of such treatment in a population with limited life expectancy has not been well documented. METHODS: Subjects with the primary diagnosis of bladder cancer were identified from the National Cancer Institute's Surveillance, Epidemiology, and End Results cancer registry between 1988 and 1999. Of the 13,796 patients diagnosed with bladder cancer, 24% were older than 80 years of age. Proportional hazards regression modeling was performed to determine the independent association of treatment strategy on overall and bladder cancer survival while adjusting for multiple covariates. RESULTS: Of patients 80 years old or older, bladder cancer management included watchful waiting (7%), radiotherapy alone (1%), full or partial cystectomy (12%), and transurethral resection (79%). Patients 80 years old or older were less likely to be treated with extirpative surgery than their younger counterparts (P <0.0001). Cox proportional hazards models demonstrated that, among patients 80 years old or older, radical cystectomy/partial cystectomy had the greatest risk reduction in death from bladder cancer (hazard ratio 0.3) and death from any cause (hazard ratio 0.4) among the primary treatment modalities (both P <0.0001). CONCLUSIONS: Disparities in practice patterns between younger and geriatric patients with bladder cancer exist. We provide compelling evidence that aggressive surgical management of bladder cancer in these patients may improve survival. Risk adjustment tools should be used to identify patients (young and old) who would be better served by less aggressive management.

Age Factors↗
PubMed2004

Trends in urology graduate medical education: a brief update from the Urology Residency Review Committee.

PURPOSE: This communication clarifies recent trends with regard to the number and configuration of urology training programs, and more precisely describes recent variations in the number of urology residents in training. MATERIALS AND METHODS: We reviewed and analyzed longitudinal data from the Accreditation Council for Graduate Medical Education regarding the number of urology resident positions as well as the number and format of urology training programs in the United States. Several publications related to general and urological graduate medical education were also reviewed. RESULTS: In response to various accreditation and demographic forces the total number of urology residency training programs has decreased by more than 20% since 1982. Coincident with this decrease was a transition in urology resident education away from smaller preceptor based programs and toward the current model of larger, broad based training programs anchored by academic medical centers. The educational format of most residency programs has also evolved, such that in 2003 all except 1 accredited program required 4 years of education in the clinical and basic urological sciences. For most programs this shift coincided with a decrease in the duration of pre-urological general surgical training. The number of first year urology residents decreased progressively between 1994 and 1998 before stabilizing at the current level of approximately 250 first year positions. In 2003 the total number of urologists in training was actually higher than it had been for most of the last decade. CONCLUSIONS: We describe recent trends in urological graduate medical education. The observations reported suggest that our specialty has maintained its focus on training a consistent number of high quality urological surgeons.

Education, Medical, Graduate↗
PubMed2004

What is the fate of the refluxing contralateral kidney in children with multicystic dysplastic kidney?

PURPOSE: We clarify the natural history of contralateral vesicoureteral reflux (VUR) in children with multicystic dysplastic kidney (MCDK), including its impact on long-term renal growth. MATERIALS AND METHODS: We performed a retrospective cohort study of 75 patients with MCDK. The primary outcomes were resolution of contralateral VUR and long-term renal growth. The Kaplan-Meier method was used to compare time to spontaneous resolution based on VUR grade. Mixed regression models were used to compare longitudinal changes in sonographic renal length. RESULTS: Contralateral VUR was present in 19 of the 75 cases (26.4%) and was low grade (I-II) in 9. After a median followup of 4.4 years spontaneous resolution was more common in patients with grades I and II (89%) versus grades III and IV VUR (50%) (p = 0.14). Median time to resolution did not differ by grade (20.1 vs 31.3 months, p = 0.3). One child underwent ureteral reimplantation and no patients had hypertension or renal insufficiency. Mixed regression analysis demonstrated no significant difference in the annual increase in renal length based on VUR status (p >0.20). CONCLUSIONS: In the largest series to date of patients with MCDK and contralateral VUR we found that spontaneous resolution in a relatively short period can be anticipated for most children. Furthermore, VUR is not a significant threat to the growth of the solitary renal unit in the first few years of life.

Cohort Studies↗
PubMed2003

Prostate carcinoma presentation, diagnosis, and staging: an update form the National Cancer Data Base.

BACKGROUND: Based on the 1998 Patient Care Evaluation (PCE) from the American College of Surgeons National Cancer Data Base (NCDB), the authors described contemporary nationwide patterns of prostate carcinoma presentation, diagnosis, and staging. METHODS: The authors reviewed 54,212 cases from the 1998 PCE. Demographics, presenting signs and symptoms, tumor characteristics, prostate biopsy techniques, and use of staging modalities were evaluated. RESULTS: The mean age of patients in the sample was 68 years. Among patients with available data, 87.5% had a prostate specific antigen (PSA) level of 4 ng/mL or higher, 83.1% had American Joint Committee on Cancer (AJCC) Stage I-II lesions, 80.2% had well or moderately differentiated cancers, and 68.7% of newly diagnosed patients were asymptomatic. Compared with symptomatic patients, asymptomatic patients were more likely to have localized disease (84.6% vs. 78.2%, P < 0.01) and well or moderately differentiated tumors (82.2% vs. 74.6%, P < 0.01). Transrectal ultrasound-guided prostate biopsy was the most common method of tissue confirmation (45.4%). Radionuclide bone scintigraphy was the most frequently employed staging modality (48.7%). Use of various staging evaluations was more frequent among patients at increased risk for disseminated disease (PSA > 10 ng/mL and/or high-grade tumors) versus patients at lower risk (PSA < or = 10 and low to moderate-grade tumors) for metastatic disease (P < 0.005). CONCLUSIONS: Most newly diagnosed patients with prostate carcinoma are asymptomatic and have moderately differentiated and organ-confined disease. Compared with symptomatic patients, tumors in asymptomatic men are associated with lower pretreatment PSA levels, AJCC stage, and tumor grade. Selective use of staging evaluations, based on risk of metastatic disease, may be relatively uncommon. The NCDB remains a unique and rich source of novel patient care information and serves as a national point of reference for prostate carcinoma presentation, diagnosis, and staging.

Aged↗
PubMed2003

Germ-line mutations of the macrophage scavenger receptor 1 gene: association with prostate cancer risk in African-American men.

Both rare germ-line mutations and common sequence variants of the macrophage scavenger receptor 1 (MSR1) gene have recently been implicated as potential prostate cancer susceptibility factors. However, existing studies are limited by the referral-based nature of samples and a paucity of African-American participants. In this context, we evaluated the association of germ-line mutations and common MSR1 sequence variants with prostate cancer risk in a case control study of a community-based sample of 134 African-American men with prostate cancer and 340 unaffected controls. In our sample, the rare Asp174Tyr missense change was identified nearly twice as frequently in men with prostate cancer (6.8%) compared with unaffected controls (3.6%; P = 0.14). Moreover, significantly different allele frequencies between cases and controls were observed for one of the sequence variants, IVS5-59 (P = 0.02). Taken together, our results provide some additional support for the hypothesis that selected, rare MSR1 mutations are associated with increased prostate cancer susceptibility among African-American men.

Black People↗
PubMed2003

Use of quality indicators to evaluate the care of patients with localized prostate carcinoma.

BACKGROUND: The goal of quality assurance in health care is to preserve and improve patient care. Recently, RAND developed a set of evidence-based candidate indicators for evaluating the quality of care for patients with localized prostate carcinoma; however, the feasibility and sensitivity of these indicators have not been tested in a clinical setting. The objectives of this study were to evaluate the feasibility of measuring these quality indicators and to determine their sensitivity to change in practice patterns over time. METHODS: One hundred sixty-eight men who presented in either 1995 or in 2000 and were treated for localized prostate carcinoma were selected randomly from the University of Michigan tumor registry. A combination of electronic data base review and explicit chart review was used to assess the feasibility of measuring compliance for each indicator. For each indicator in which assessment was feasible, compliance with the RAND indicators was determined for patients in both years. Multivariate regression analysis was used to adjust for potential confounding effects of disease stage, tumor grade, prostate specific antigen (PSA) level, patient age, and therapy. RESULTS: Based on review of available clinical data, measurement of compliance was feasible for 19 of 22 RAND candidate quality indicators (86%). For five indicators, significant differences in documentation (compliance) were detected between 1995 and 2000 (P < 0.05). Treatment received and higher PSA levels were associated independently with documentation of compliance for several indicators (P < 0.05). CONCLUSIONS: Measurement of the majority of the RAND quality indicators for the treatment of patients with localized prostate carcinoma was feasible, and improvements in several indicators were observed between 1995 and 2000. Demonstration of such variation, even within a single institution, suggests that the indicators are sufficiently sensitive to detect differences in practice patterns.

Aged↗
PubMed2003

The impact of co-morbid disease on cancer control and survival following radical cystectomy.

PURPOSE: We clarified the impact of concurrent medical disease on tumor control and survival following radical cystectomy. MATERIALS AND METHODS: A total of 106 consecutive patients with clinically localized (cT2 or less) disease underwent radical cystectomy at the University of Michigan between 1997 and 1998. The Charlson Index, a validated risk adjustment index, was used to assess preoperative co-morbidity. The 3 primary end points were pathological stage, disease specific survival and overall survival. Logistic regression models were used to determine the relationship between Charlson Index and pathological stage, while Cox regression models were used for the 2 survival end points. RESULTS: Of our study population 24% had a Charlson Index score of 2 or greater. Myocardial infarction, nonurothelial solid malignancies and cerebrovascular disease were the most common co-morbid conditions at 14%, 12% and 10%, respectively. On bivariate analysis the Charlson Index was significantly associated with decreased disease specific (p = 0.049) and overall (p = 0.016) survival. In a multivariate model the index was independently associated with decreased cancer specific survival (p = 0.049) and increased risk of extravesical disease (p = 0.033). CONCLUSIONS: We demonstrated an association between co-morbid illness and adverse pathological and survival outcome following radical cystectomy. This finding underscores the value of assessing overall health before recommending and proceeding with surgery. Moreover, our results emphasize the need to adjust for co-morbidity when comparing outcomes following radical cystectomy.

Aged↗
PubMed2003

Percutaneous cystolithotomy using a laparoscopic entrapment sac.

OBJECTIVES: To describe a percutaneous approach that uses laparoscopic techniques and technology to achieve intact removal of bladder stones after augmentation cystoplasty. METHODS: Percutaneous stone removal using a laparoscopic entrapment sac was performed in 4 patients with augmented bladders. Under endoscopic guidance, a 10-mm laparoscopic trocar was placed percutaneously into the augmented bladder using the previous suprapubic tube site. The stones were then maneuvered into a laparoscopic entrapment sac and extracted intact without lithotripsy. RESULTS: Percutaneous removal of the entire stone burden (up to seven stones in 1 patient) was achieved in 3 of 4 patients. The total operative time was less than 1 hour in each of these cases. Partial conversion to open cystolithotomy was required in 1 patient, because of tearing of the entrapment sac. Three of 4 cases were performed on an outpatient basis and less than 24 hours of catheter drainage was required in all but 1 patient. CONCLUSIONS: Percutaneous cystolithotomy using a laparoscopic entrapment sac is a safe, useful, and minimally invasive modification of contemporary percutaneous techniques. In patients with augmented bladders, application of this technique may minimize the risk of residual fragments and obviate the need for adjuvant lithotripsy.

Adolescent↗