Telomerase is a highly sensitive and specific molecular marker in fine-needle aspirates of breast lesions.

PURPOSE: Telomerase has been detected in a majority of human malignant tumors, making telomerase activity (TA) one key difference between mortal and immortal cells. In this study, we evaluated in blind-trial fashion the association of TA with cytologic and final clinical/pathologic diagnosis in fine-needle aspirates (FNAs) of breast lesions. MATERIALS AND METHODS: In 172 FNAs, including 80 samples that were cytologically malignant, 18 that were atypical but not diagnostic for malignancy, and 74 that were cytologically benign, TA was determined by a modified nonradioactive telomeric repeat amplification protocol (TRAP) assay. Final diagnosis was made by pathologic examination of follow-up surgical material available for all the cytologically malignant samples, a majority of the cytologically atypical samples, and a portion of the cytologically benign samples. RESULTS: TA was detected in 85 of 172 samples. Comparison of the cytologic and histologic diagnoses with TA showed that 80 of 87 samples from patients with breast cancer were telomerase-positive, resulting in a sensitivity of 92%. TA was found in four of five FNAs from carcinomas that were considered cytologically atypical but not diagnostic for malignancy. Eighty of 85 samples from patients with benign breast lesions were telomerase-negative, revealing a specificity of 94%. The five positive cases in this group were all fibroadenomas with low TA. Among the 18 cases with a cytologic diagnosis of atypia, there was a strong positive relationship between TRAP findings and histologic diagnosis. CONCLUSION: The detection of TA in FNAs of breast lesions is a highly sensitive and specific marker of malignancy and may be used as an adjunct in cases with an equivocal cytologic diagnosis.

Mild renal failure is associated with adverse outcome after cardiac valve surgery.

The present study was performed to ascertain whether the presence of mild renal failure (defined as a serum creatinine concentration of 1. 5 to 3.0 mg/dL) is an independent risk factor for adverse outcome after cardiac valve surgery. An extensive set of preoperative and postoperative data was collected in 834 prospectively evaluated patients undergoing cardiac valve surgery at 14 Veterans Affairs Medical Centers. Univariate and multivariable analyses were performed to determine whether an independent association of mild renal dysfunction with adverse outcomes was present. Patients with mild renal failure had significantly greater 30-day mortality rates (P = 0.001; 16% versus 6%) and frequency of postoperative bleeding (P = 0.023; 16% versus 8%), respiratory complications (P = 0.02, 29% versus 16%), and cardiac complications (P = 0.002; 18% versus 7%) than patients with normal renal function (serum creatinine <1.5 mg/dL) when controlling for multiple other variables. The presence of a serum creatinine concentration of 1.5 to 3.0 mg/dL is significantly and independently associated with adverse outcomes after cardiac valve surgery.

Quantitative telomerase expression in glioblastomas shows regional variation and down-regulation with therapy but no correlation with patient outcome.

Despite the nearly ubiquitous expression of telomerase in almost all types of malignant human tumors, studies have shown widely varying positivity in the highest-grade glioma, the glioblastomas (GBMs), ranging from 26% to 100% of tumors analyzed. We have previously shown significant variability in positive versus negative telomerase expression from region to region within the same GBM. In this study, we hypothesized that application of new quantitative methodology would extend our previous observations and identify whether there is heterogeneity in levels of protein expression even within areas positive for telomerase in high-grade gliomas. Finally, we sought to correlate quantitative telomerase expression with patient outcome and therapeutic response. Quantitative analysis was achieved by polymerase chain-based TRAP assay with phosphorimager analysis and compared with clinical information obtained from 19 patients, most with primary, untreated GBMs. Results showed up to 3-fold variability in telomerase levels across multiple regional samples from the same patient, as well as between patients. In 5 of 6 patients with recurrent tumors who had received intervening radiation therapy or chemotherapy, telomerase was downregulated in the second, post-therapy sample. These data provide in vivo corroboration of recent in vitro experiments showing telomerase downregulation after radiation therapy or chemotherapy treatment of cell lines. Our finding of variability in levels of telomerase expression in GBMs parallels the known heterogeneity of these tumors for histologic features and cell growth-related factors. Statistical analysis showed no relationship between TRAP score and either time to clinical progression or time to death.

Clinical science research.

Clinical science research incorporates the fields of clinical investigation and health services research. With a focus on the use of either human specimens or subjects, clinical investigation research projects translate knowledge gained from basic science research based on animal models for disease. The goal of clinical investigation is to develop new prevention, intervention, and therapeutic approaches to improve patient clinical outcomes. In contrast, health services research focuses on the improvement of the efficacy, cost-effectiveness, and outcomes of care. Health services research projects examine options to improve the health care delivery system, organization, financing, and reimbursement mechanisms in place today. The purpose of this article is to review common terminology and methodologic approaches that are used in clinical science research. The process of designing a research project is reviewed. Beginning with the development of a research question and hypothesis, the steps for successful completion of the project are discussed. Different study design approaches are presented with their respective strengths and weaknesses. The challenges associated with conducting a clinical research study are discussed, including the development of an appropriate sampling strategy, the designing of data collection, instruments, and the assurance of study data integrity. Possible threats to study validity and generalizability are assessed.One the major advantages of clinical research is that it offers an opportunity to study clinical questions in the clinical setting without the expenses of a basic research laboratory and basic science technology. Thus important clinical questions related to patient care, new technology assessment, clinical practice management, health care administration, or health policy may be addressed.

Infant heart transplantation: improved intermediate results.

OBJECTIVES: Our objectives were to (1) review our experience with heart transplants in infants (age < 6 months), (2) delineate risk factors for 30-day mortality, and (3) compare outcomes between our early and recent experience. METHODS: Records of all infants listed for transplantation in our center before September 1996 were analyzed. Early and recent comparisons were made between chronologic halves of the accrual period. Univariate analysis was used to analyze potential risk factors for 30-day mortality (categorical variables, Fisher's exact test; continuous variables, nonparametric Wilcoxon rank-sum test). Multivariable analysis included univariate variables with p values < or = 0.10. Actuarial survivals were estimated (Kaplan-Meier) and compared by the log-rank test. RESULTS: Fifty-one of the 60 infants listed for transplantation were operated on (waiting list mortality 15%). Thirty-day mortality was 18% overall, 30% in the first 3 years and 10% in the last 3 years (p = 0.07). Sepsis was the commonest cause of early death (4/9). Univariate analysis suggested four potential risk factors for early death: preoperative mechanical ventilation (p = 0.01), prior sternotomy (p = 0.002), preoperative inotropic drugs (p = 0.08), and warm ischemia time (p = 0.08). Multivariable analysis indicated that prior sternotomy (p = 0.01) was an independent risk factor for 30-day mortality. Actuarial survivals were 80%, 78%, and 70% at 1, 2, and 3 years, and these figures improved between early and recent groups (p = 0.05). Late deaths were most commonly due to acute rejection (3/5). CONCLUSIONS: Results of heart transplantation in infancy improve with experience. Prior sternotomy increases initial risk. Intermediate-term survival for infants with end-stage heart disease is excellent.

Detection of human papillomavirus in anorectal squamous cell carcinoma. Correlation with basaloid pattern of differentiation.

Polymerase chain reaction (PCR) and in situ hybridization were used to test for the presence of human papillomavirus (HPV) DNA in cases of anorectal squamous cell carcinoma. Human papillomavirus was detected by PCR with L1 consensus sequence primers in 22 of 27 cases, including 10 of 11 cases with a prominent basaloid pattern and 12 of 16 cases without basaloid patterns of differentiation. Slot blot hybridization identified HPV type 16 as the most common type, present in 7 of 10 cases of basaloid carcinoma and 10 of 12 cases without basaloid features. In situ hybridization confirmed the presence of HPV in tumor cell nuclei of five cases of basaloid carcinoma and in eight cases of squamous cell carcinoma without basaloid pattern. The authors conclude that the prevalence of HPV in cases of anorectal squamous cell carcinoma is unrelated to the presence or absence of a basaloid pattern of differentiation.

Telomerase expression in human breast cancer with and without lymph node metastases.

Telomerase is a ribonucleoprotein enzyme that synthesizes telomeric DNA onto the ends of chromosomes, thereby preventing the replication-dependent shortening of these ends. Telomerase activity is detected in a wide range of cancers of various tissues, and its expression may be a critical step in tumor progression. The telomeric repeat amplification protocol was used to compare telomerase activity in breast cancers with and without lymph node metastases, as well as in fibroadenomas and normal breast tissue. Expression of telomerase was detected in 22 (79%) of 28 primary breast cancers, which included 16 (73%) of 22 cancers positive and 6 (100%) of 6 cancers negative for axillary lymph node metastases. It was detected in 1 (11%) of 9 fibroadenomas but was negative in 13 normal breast tissues. There was no statistical difference in expression of telomerase between axillary node-negative primary breast cancers and similar tumors with nodal metastasis (P = .289). Further, no statistical association was found between telomerase activity and tumor size (P = .679) or hormonal status (P = .178). The difference in telomerase activity among breast cancers vs fibroadenomas and normal breast tissues, however, was statistically significant (P < .001). Although normal breast tissue does not express telomerase, both node-positive and node-negative breast cancers express telomerase. The possible significance of telomerase expression in fibroadenomas remains open to further investigation.

Telomerase expression in normal epithelium, reactive atypia, squamous dysplasia, and squamous cell carcinoma of the uterine cervix.

Telomerase activity has been detected in a broad range of human malignant neoplasms, and its expression may represent an essential step in the malignant transformation of tissues; however, the expression of telomerase in premalignant lesions remains relatively unexplored. We tested tissue sections of cervical squamous cell carcinomas and squamous intraepithelial lesions, samples of benign reactive atypia, and normal cervical mucosa from hysterectomy and cone biopsy specimens for the expression of telomerase. Mirror-image sections from each sample were paraffin embedded and processed for histologic analysis. The test samples of cervical tissue were crushed under liquid nitrogen, and telomerase activity was determined by the telomeric repeat amplification protocol. Telomerase activity was detected in 18 of 18 cases (100%) of invasive squamous cell carcinoma. Twenty-five of 26 samples (96%) of high-grade squamous intraepithelial lesion also tested positively for telomerase activity, including 10 of 10 samples of moderate dysplasia, 12 of 13 samples of severe dysplasia, and 3 of 3 samples of carcinoma in situ. Telomerase activity was detected in 14 of 25 samples (56%) of low-grade squamous intraepithelial lesion and in 10 of 18 samples (56%) of reactive atypia but was detected in only 9 of 50 samples (18%) of histologically normal cervical mucosa. These results suggest that telomerase expression may be a marker of premalignant and malignant squamous cell lesions of the uterine cervix, although it is also expressed in a high proportion of cases of reactive atypia.

Telomerase expression shows differences across multiple regions of oligodendroglioma versus high grade astrocytomas but shows correlation with Mib-1 labelling.

AIMS/BACKGROUND: Telomerase is an enzyme that is expressed in most human neoplasms and is associated with tumour immortality. Determination of the point in neoplastic transformation at which telomerase is expressed may aid the understanding of tumour pathogenesis and progression. Despite numerous reports on telomerase, few studies have investigated its expression in high grade glial tumours. These studies, performed on archival banked, single brain tumour specimens, have shown conflicting results for oligodendrogliomas and unexpectedly negative results for telomerase expression in high grade astrocytomas, with one third to one half of glioblastoma multiformes being negative. METHODS: 34 rapidly banked glioma specimens taken from patients undergoing gross total surgical resection of their tumours were studied. Telomerase expression was assessed across 3-8 sampled regions from each tumour by the telomeric repeat amplification protocol (TRAP) assay. Matched mirror image tissue samples were taken for histological analysis of tissue adequacy, statistical correlation of telomerase with tumour histological features, Mib-1 (a marker for cell cycling) labelling, and p53 immunohistochemistry. RESULTS: All five well differentiated oligodendrogliomas were homogeneously telomerase negative and two of three untreated anaplastic oligodendrogliomas were homogeneously positive. In contrast, 10 of 14 high grade astrocytomas showed heterogeneity for telomerase expression across the multiple regions sampled. All glioblastoma multiformes and two of three anaplastic astrocytomas showed at least one region positive for telomerase. When test samples were individually assessed in both oligodendrogliomas and high grade astrocytomas, telomerase expression was associated with Mib-1 labelling (p < 0.001). For the entire group, telomerase expression was associated with grade of tumour, age of patient, and vascular endothelial proliferation (all p < 0.001). CONCLUSIONS: This regional study clarifies that all glioblastoma multiformes are at least focally positive and that telomerase expression correlates with tumour grade in oligodendrogliomas. Homogeneity versus heterogeneity for telomerase expression across multiple regions of oligodendrogliomas versus high grade astrocytomas may provide important preclinical data on the use of antitelomerase agents in these adult glial tumours.

Localization of telomerase hTERT protein and survivin in placenta: relation to placental development and hydatidiform mole.

OBJECTIVE: To find if a difference in telomerase or survivin expression exists between non-neoplastic tissues and hydatidiform moles, and explore expression of those proteins in normal placental development, post-term gestation, and preeclampsia. METHODS: Formalin-fixed placental tissues were selected from collections of the Department of Pathology at the University of Colorado. Five specimens of each trimester, five each of preeclamptic and post-term placentas, and 23 molar pregnancies were selected. The telomerase catalytic protein hTERT was localized in placental tissues using the catalyzed signal amplification system, and survivin was localized by conventional immunoperoxidase method. Staining was graded on a scale of zero to 4. RESULTS: hTERT staining was detected in sections of 42 of 48 specimens (23 of 23 hydatidiform moles, 19 of 25 non-neoplastic placental tissues). The intensity of staining for hTERT was higher in hydatidiform moles (mean 3.3, median 3) compared with levels in non-neoplastic placental tissues (mean 0.92, median 1) (P <.001). Survivin was detected in 39 of 48 specimens (22 of 23 hydatidiform moles, 17 of 25 non-neoplastic placental tissues). Compared with non-neoplastic tissues (mean 0.88, median 1), survivin levels were elevated in hydatidiform moles (mean 1.35, median 1) (P =.031). CONCLUSION: Survivin and telomerase were increased in hydatidiform moles, suggesting that regulation of apoptosis and stabilization of telomere length might be involved in neoplastic transformation of the placenta. The patterns of expression observed for survivin and telomerase in non-neoplastic placental tissues suggest that the control of apoptosis and stabilization of telomeric DNA might also be involved in normal gestational development.

Analysis of clonality by polymerase chain reaction for phosphoglycerate kinase-1. Heteroduplex generator.

Polymerase chain reaction (PCR) amplification has been used to determine the clonal composition of tissues based on analysis of the pattern of X-chromosome inactivation, but its use has been limited by technical difficulties. This report presents an expedited method to use PCR in the analysis of clonality. The method uses gel electrophoresis of heteroduplexes formed with an artificial heteroduplex generator (HG) and PCR products from the phosphoglycerate kinase-1 (PGK-1) gene from the tissue sections. Amplification was successful in 36 of 37 cases originally diagnosed as endometrial adenocarcinoma. HG analysis of 36 cases confirmed heterozygosity in 12 cases (33.3%). PGK-1 PCR amplification product was obtained from both control and lesional tissue in 10 of the 12 heterozygous cases. Of these 10 cases, seven were shown to consist of clonal cell populations by HG analysis. Two of three cases diagnosed as well-differentiated endometrioid adenocarcinoma were found to be comprised of polyclonal populations of cells. One case produced an anomalous pattern with HG analysis and was shown to be aneuploid by fluorescence in situ hybridization (FISH) with a chromosome X alpha-satellite probe. It is concluded that HG is a useful alternative to restriction fragment length polymorphism (RFLP) analysis of X-chromosome inactivation as a marker of tissue clonality in cases in women.

Quality initiatives and the power of the database: what they are and how they run.

The criteria by which healthcare is judged or measured are quality, accessibility, and cost effectiveness. To evaluate these criteria it is important to have a database. There are many strengths and weakness to large databases. They can be used as an indicator of the level of performance or quality, for clinical decision making, and as a measurement of cost effectiveness. They can also be useful in the evaluation and development of treatment algorithms and critical pathways for patients with entry level disease. In addition, they can measure patient access to healthcare and the appropriateness of care. It is important for these databases to appropriately adjust for preoperative risk factors that may influence outcome. Outcome in most of the databases is measured by mortality, but morbidity, functional status, quality of life, cost of care, length of stay, return to work, and patient satisfaction are also important outcomes. Factors that can influence the quality of the outcome data are the methods by which the data are collected, standardization of definitions, the currentness of the database, adequate numbers of patients and outcomes, and appropriate analytic techniques. It is important to feed back the data to the healthcare providers in a timely enough fashion so that processes and structures of care can be modified to improve treatment and results. The reliability of the databases and the validity must be substantiated for the healthcare provider to have confidence in the database.(ABSTRACT TRUNCATED AT 250 WORDS)

Bayesian-logit model for risk assessment in coronary artery bypass grafting.

Predictive models for the assessment of operative risk using patient risk factors have gained popularity in the medical community as an important tool for the adjustment of surgical outcome. The Bayes' theorem model is among the various models used to predict mortality among patients undergoing coronary artery bypass grafting procedures. Comparative studies of the various classic statistical techniques, such as logistic regression, cluster of variables followed by a logistic regression, a subjectively created sickness score, classification trees model, and the Bayes' theorem model, have shown that the Bayes' model is among those with the highest predictive power. In this study, the Bayes' theorem model is reformulated as a logistic equation and extended to include qualitative and quantitative risk factors. We show that the resulting model, the Bayesian-logit model, is a mixture of logistic regression and linear discriminant analysis. This new model can be created easily without complex computer programs. Using 12,712 patients undergoing coronary artery bypass grafting procedures at the Department of Veterans Affairs Continuous Improvement in Cardiac Surgery Study between April 1987 and March 1990, the predictive power of the Bayesian-logit model is compared with the Bayes' theorem model, logistic regression, and discriminant analysis. The ability of the Bayesian-logit model to discriminate between operative deaths and operative survivors is comparable with that of logistic regression and discriminant analysis.

Calculating risk and outcome: the Veterans Affairs database.

The methodology used by the Department of Veterans Affairs for data collection and analysis to derive observed/expected mortality ratios in cardiac surgical patients is reviewed. The Department of Veterans Affairs' use of univariate and multivariate analysis to develop risk ratios for individual risk factors is described. Its experience with tracking observed/expected mortality and morbidity associated with cardiac surgery and length of hospital stays is reviewed. Results of the Department of Veterans Affairs study of the relationship between hospital surgical volume and observed/expected ratios are reported. Feasible goals for the improvement of the predictive capability of database models and the limitations affecting model accuracy are discussed.

1995 coronary artery bypass risk model: The Society of Thoracic Surgeons Adult Cardiac National Database.

BACKGROUND: The Society of Thoracic Surgeons (STS) Adult Cardiac National Database has recently completed the development of the 1995 risk model to be used to estimate the risk of operative death for isolated coronary artery bypass graft (CABG) procedures. This article describes the detailed methodology used, as well as a new Expert Advisory Panel review mechanism that was initiated by The Society. METHODS: Placing emphasis on clinical relevance, data quality, data completeness, and univariate analyses, a logistic regression analysis was used to develop the 1995 CABG-only risk model. The STS National Office invited an Expert Advisory Panel (composed of nationally recognized, independent biostatisticians) to review the modeling process used. RESULTS: The 1995 CABG-only model details are reported. Standard performance measures indicated the model had high predictive power and an acceptable level of calibration. The Expert Advisory Panel reviewed the 1995 CABG model and concluded that the current modeling techniques were adequate. Suggestions for future model development and reporting were proposed by the Panel. CONCLUSIONS: The most current STS risk model of CABG operative mortality is a reliable and statistically valid tool. Its development and performance have been critically examined and approved by an independent panel of experts.

Updates to the Data Quality Review Program: the Society of Thoracic Surgeons Adult Cardiac National Database.

To ensure the credibility of this voluntary database, The Society of Thoracic Surgeons' National Database Audit and Validation Sub-Committee has been working during the past year to update and expand the group practice-based indicators used to assess the completeness, accuracy, and generalizability of the Adult Cardiac National Database. With increasing frequency, questions have been raised by third-party payors and regional/state-based groups as to the integrity of the data retained in the Adult Cardiac National Database. To work in conjunction with the Audit and Validation Sub-Committee to explicitly examine these issues, The Society of Thoracic Surgeons initiated a new Expert Advisory Panel review mechanism. This article describes the expanded data completeness and quality criteria that will be implemented in the coming year and summarizes the Expert Advisory Panel's recommendations for improvement.

The Veterans Affairs Continuous Improvement in Cardiac Surgery Study.

The Department of Veterans Affairs Cardiac Surgery Consultants Committee is responsible for reviewing the quality of cardiac surgical treatment at the 43 Veterans Affairs cardiac surgical centers where these procedures are performed. It does so by reviewing both the unadjusted and risk-adjusted operative mortality data and the incidence of perioperative complications. These data are reviewed by the committee semiannually, and the overall summary and hospital-specific data are shared with the individual cardiac surgical program directors. Paper audits and site visits are performed when indicated by increased unadjusted and risk-adjusted operative mortality. Constructive criticism is shared with the program director and medical center administration. The relative risk of death for numerous patient risk factors has been estimated, and is now used in prospective clinical decision making. During the 7-year period that risk-adjusted outcomes have been utilized, there has been an overall significant reduction in the observed-to-expected operative mortality ratio. Although many factors could have contributed to this, including continually improving surgical techniques, it is also likely that part of this improvement has occurred because of the continuous feedback of these quality improvement data to our cardiothoracic surgeons and cardiologists.

Provider perceptions in using outcomes data to improve clinical practice.

In this article we report on the perceptions of health care providers concerning the use of health care outcomes. These perceptions were identified during two afternoon workshops at the symposium on outcomes data held in Keystone, Colorado, in June 1994. The overall goal of these workshops was to explore the potential use of outcomes data within the clinical practice setting. The attitudes and concerns of several key providers formed the framework for the workshop discussions. The strengths and weaknesses associated with using risk-adjusted outcomes data, both to assess and to improve quality of patient care, were debated within the workshop groups. Overall, conference participants agreed that the risk-adjusted outcomes of cardiac care could be used both to assess and to improve the quality of patient care. The research to date, however, represents only a first step toward this goal. The meeting participants challenged the research community to improve on the measures currently available, with the goal of providing clinicians better information to improve the "art" of medicine.

The Society of Thoracic Surgeons National Cardiac Surgery Database: current risk assessment.

BACKGROUND: The Society of Thoracic Surgeons National Cardiac Surgery Database has recently completed gathering patient data from 1990 through 1994. Using information from more than 300,000 patients undergoing isolated coronary artery bypass grafting in this period, new risk models of operative mortality were developed. METHODS: Logistic regression analysis was used to develop a risk model for each calendar year. A standard "training set/test set" approach was used for each model. RESULTS: Five validation techniques were used to evaluate the reliability of the risk models. All models were found to predict operative mortality with good accuracy in this population. CONCLUSIONS: The new risk models for isolated coronary artery bypass operations serve as reliable predictors of operative mortality for the most recent harvest of patient data from The Society of Thoracic Surgeons National Cardiac Surgery Database.

Off-pump coronary artery bypass grafting decreases risk-adjusted mortality and morbidity.

BACKGROUND: The purpose of this study was to determine whether coronary artery bypass grafting without cardiopulmonary bypass (off-pump CABG) decreases risk-adjusted operative death and major complications after coronary artery bypass grafting in selected patients. METHODS: Using The Society of Thoracic Surgeons (STS) National Adult Cardiac Surgery Database, procedural outcomes were compared for conventional and off-pump CABG procedures from January 1, 1998, through December 31, 1999. Mortality and major complications were examined, both as unadjusted rates and after adjusting for known base line patient risk factors. RESULTS: A total of 126 experienced centers performed 118,140 total CABG procedures. The number of off-pump CABG cases was 11,717 cases (9.9% of total cases). The use of an off-pump procedure was associated with a decrease in risk-adjusted operative mortality from 2.9% with conventional CABG to 2.3% in the off-pump group (p < 0.001). The use of an off-pump procedure decreased the risk-adjusted major complication rate from 14.15% with conventional CABG to 10.62% in the off-pump group (p < 0.0001). Patients receiving off-pump procedures were less likely to die (adjusted odds ratio 0.81, 95% CI 0.70 to 0.91) and less likely to have major complications (adjusted odds ratio 0.77, 95% CI 0.72 to 0.82). CONCLUSIONS: Off-pump CABG is associated with decreased mortality and morbidity after coronary artery bypass grafting. Off-pump CABG may prove superior to conventional CABG in appropriately selected patients.