Phase 1/2 trial of single-session stereotactic body radiotherapy for previously unirradiated spinal metastases

BACKGROUND

In this phase 1/2 study, the authors tested the hypothesis that single-fraction stereotactic body radiotherapy (SBRT) for previously unirradiated spinal metastases is a safe, feasible, and efficacious treatment approach.

METHODS

All patients were evaluated by a multidisciplinary team. Spinal magnetic resonance imaging studies were obtained before treatment and at regular intervals to define both target volume and response to treatment. SBRT was delivered to a peripheral dose of 16 to 24 grays in a single fraction while limiting the dose to the spinal cord. Higher doses were used for renal cell histology. The National Cancer Institute Common Toxicity Criteria 2.0 and McCormick neurologic function score were used as toxicity assessment tools.

RESULTS

In total, 61 patients who had 63 tumors of the noncervical spine were enrolled and received SBRT between 2005 and 2010 on a prospective, phase 1/2 trial at The University of Texas M. D. Anderson Cancer Center. The mean follow-up was 20 months. The actuarial 18-month imaging local control rate for all patients was 88%, the actuarial 18-month overall survival rate for all patients was 64%, and the median survival for all patients was 30 months. No significant differences in outcomes were noted with respect to tumor histology or SBRT dose. Two patients experienced radiation adverse events (grade 3 or higher). The actuarial rate of 18-month freedom from neurologic deterioration from any cause was 82%.

CONCLUSIONS

Data from this phase 1/2 trial supported an expanded indication for SBRT as first-line treatment of spinal metastases in selected patients. The authors concluded that additional studies that can prospectively identify predictive factors for spinal cord toxicity after SBRT are warranted to minimize the incidence of this serious yet rare complication.

Microsatellite instability in saliva from patients with hereditary non-polyposis colon cancer and siblings carrying germline mismatch repair gene mutations

Microsatellites are short tandem repeats of deoxyribonucleic acid (DNA) sequences which are distributed throughout the genome. Tumors in patients with Lynch syndrome tend to accumulate mutations in microsatellites at a much higher rate than other sequences in the genome resulting in microsatellite instability (MSI). This is due to germline mutations in mismatch repair (MMR) genes. Using small pool-polymerase chain reaction (SP-PCR), previous studies have shown that mutant alleles can be detected in microsatellites of DNA from peripheral blood lymphocytes (PBLs) of Lynch syndrome patients at frequencies that were low, but significantly higher than frequencies in PBLs of age-matched non-Lynch syndrome controls. In the present study, SP-PCR detection of frequency of mutant MSI alleles (FMMA) was performed on PBLs and saliva samples from four sets of families. Each family set consisted of a mutation carrying affected proband (initial tumor bearer), a germline mutation-carrier sibling without tumors, and an age-matched normal control, either related (for 3 family sets) without mutation carrier status or unrelated (for 1 family set) without mutation carrier status. FMMAs of saliva and PBL DNA were compared between each proband, sibling and control for each family set, and between family sets. In all five statistically significant saliva comparisons identified between germline mutation carriers (FMMA: 0.080-0.261) and normal controls (FMMA: 0.003-0.087), the measured FMMAs were always higher in the carriers (p < 0.05). A logistic regression model of the data showed a significant increase in FMMAs in saliva DNA from siblings with MMR mutation compared to the normal controls (p < 0.001). These results indicated that the increased FMMAs observed in the saliva DNA as well as PBL DNA of MMR gene mutation carriers compared to normal controls are real and repeatable. Furthermore, the logistic regression also indicated that the FMMAs seen in saliva were nearly double those seen in PBLs (p < 0.001). Saliva testing, a less-invasive procedure than PBL testing, is more sensitive and appears to be a viable alternative for identifying MSI in carriers with MMR mutations.

Microsatellite instability in the peripheral blood leukocytes of HNPCC patients

Most hereditary nonpolyposis colorectal cancer (HNPCC) patients inherit a defective allele of a mismatch repair (MMR) gene, usually MLH1 or MSH2, resulting in high levels of microsatellite instability (MSI-H) in the tumors. Presence of MSI in the normal tissues of mutation carriers has been controversial. Here we directly compare MSI in the peripheral blood leukocyte (PBL) DNA of seven HNPCC patients carrying different types of pathogenic MMR mutations in MLH1 and MSH2 genes with the PBL DNA of normal age-matched controls and of patients with sporadic colorectal cancer (SCRC). Small pool PCR (SP-PCR) was used studying three microsatellite loci for at least 100 alleles each in most samples. The average frequencies of mutant microsatellite fragments in each HNPCC patient (0.04-0.24) were significantly higher (p<0.01) relative to their age-matched normal controls with mutant frequencies (MF) from 0.00 to 0.06, or SCRC patients (MF from 0.01-0.03). The data support the conclusions that higher MF in the PBL DNA of HNPCC patients is real and reproducible, may vary in extent according to the type of germline MMR mutation and the age of the individual, and provide a possible genetic explanation for anticipation in HNPCC families.

Phase I/II study of stereotactic body radiotherapy for spinal metastasis and its pattern of failure

OBJECT

The authors report data concerning the safety, effectiveness, and patterns of failure obtained in a Phase I/II study of stereotactic body radiotherapy (SBRT) for spinal metastatic tumors.

METHODS

Sixty-three cancer patients underwent near-simultaneous computed tomography-guided SBRT. Spinal magnetic resonance imaging was conducted at baseline and at each follow-up visit. The National Cancer Institute Common Toxicity Criteria 2.0 assessments were used to evaluate toxicity.

RESULTS

The median tumor volume of 74 spinal metastatic lesions was 37.4 cm3 (range 1.6-358 cm3). No neuropathy or myelopathy was observed during a median follow-up period of 21.3 months (range 0.9-49.6 months). The actuarial 1-year tumor progression-free incidence was 84% for all tumors. Pattern-of-failure analysis showed two primary mechanisms of failure: 1) recurrence in the bone adjacent to the site of previous treatment, and 2) recurrence in the epidural space adjacent to the spinal cord. Grade 3 or 4 toxicities were limited to acute Grade 3 nausea, vomiting, and diarrhea (one case); Grade 3 dysphagia and trismus (one case); and Grade 3 noncardiac chest pain (one case). There was no subacute or late Grade 3 or 4 toxicity.

CONCLUSIONS

Analysis of the data obtained in the present study supports the safety and effectiveness of SBRT in cases of spinal metastatic cancer. The authors consider it prudent to routinely treat the pedicles and posterior elements using a wide bone margin posterior to the diseased vertebrae because of the possible direct extension into these structures. For patients without a history of radiotherapy, more liberal spinal cord dose constraints than those used in this study could be applied to help reduce failures in the epidural space.

Microsatellite instability (MSI) increases with age in normal somatic cells

Small pool PCR (SP-PCR) is a sensitive method for the detection and quantification of microsatellite instability (MSI) in somatic cells. Here we propose that mutant microsatellite fragments accumulate with age in normal somatic cells and that this increase in MSI can be quantified by SP-PCR. MSI at 6 microsatellite loci was determined by SP-PCR in PBL DNA from 17 "normal" blood bank donors. These individuals varied in age from 20 to 67 y/o. MSI phenotypes were plotted against age in a regression analyses. A positive slope indicated a correlation between age and MSI phenotype (p=0.0006). The mean weighted average mutant frequencies across all loci for all individuals in the age groups (0.009 for 20-30 y/o; 0.019 for 35-50 y/o; 0.034 for 60-70 y/o) were also significantly different from each other (p<0.01). A baseline for increases of MSI with age in human somatic cells was therefore begun and the effectiveness of SP-PCR to evaluate low, but significant, levels of MSI, established.

Generation or birth cohort effect on cancer risk in Li-Fraumeni syndrome

Genetic anticipation is the increased incidence, earlier onset, or increased severity of a disease in successive generations. Before the biological basis of anticipation had been demonstrated, the phenomenon was thought to be due to sampling bias, epigenetic effects, gene conversion, or recombinant events. Since then, the biologic basis for anticipation in a number of neurodegenerative disorders has been shown to be attributable to trinucleotide repeat instability, with expansion of repeats clearly correlated with an earlier age of onset. Recently, telomere shortening has been suggested as the mechanism for anticipation in the autosomal dominant form of dyskeratosis congenita, attributable to mutations in the TERC gene, leading to dysfunctional telomeres (Vulliamy et al. 2004). However, the pattern of anticipation has been observed in other disorders, including cancers, for which no genetic defect has been identified. In this study, we assess the apparent generation effect on cancer incidence in ten extended families with P53 germline mutation, identified through probands diagnosed with childhood sarcoma. The probands were from two sets of systematically ascertained sarcoma patients treated at the University of Texas M. D. Anderson Cancer Center between 1944 and 1982. From those overall studies, we have identified ten kindreds having germline P53 mutations in more than one generation. We compared the cancer incidence in members of successive generations of these families with P53 mutations (carriers) and with no P53 mutations (noncarriers). In carriers, cancer incidence increased in succeeding generations; there was no evidence for this effect in noncarriers; however, the noncarrier population was too small to rule it out. The apparent lack of increase in incidence in noncarriers argues against a cohort effect explaining the increase in carriers.

Estimating mutant microsatellite allele frequencies in somatic cells by small-pool PCR

Identifying microsatellite instability (MSI) by partitioning DNA into multiple small pools containing only single genome amounts of DNA results in trapping both progenitor and low-frequency mutant alleles into pools where they can be identified and counted following PCR. Statistical approaches determining both the frequencies and the significant differences between frequencies of these Poisson-distributed alleles are presented. Results indicate a level of sensitivity and quantification not possible by standard PCR methods. Using material from colon cancer patients with high levels of MSI in their tumors, we also present the molecular and robotic methods for carrying out such studies. Validation experiments indicated mutants detectable at frequencies >0.03 above background. Frequencies obtained in tumor tissue (>0.25) met the expectations of the approach. Significant levels of MSI were detected in the constitutive tissue of the patient carrying a germ-line mutation for mismatch repair, suggesting both mechanistic and clinical applications of the procedure.

Phase I clinical evaluation of near-simultaneous computed tomographic image-guided stereotactic body radiotherapy for spinal metastases

PURPOSE

To evaluate in a Phase I study the safety, feasibility, and patient-positioning accuracy of treating patients with intensity-modulated, near-simultaneous, computed tomographic (CT) image-guided stereotactic body radiotherapy (SBRT).

PATIENTS AND METHODS

Fifteen consecutive patients with metastatic spinal disease who met protocol eligibility criteria were entered into a Phase I clinical trial. Each patient received five treatments of intensity-modulated, near-simultaneous CT image-guided SBRT, for a total of 75 treatments with 90 isocenter setups during the course of the study. Patients uniformly received 30 Gy (if possible) of radiotherapy in 5 fractions to the clinical target volume. The total dose was constrained by limiting the spinal cord to a maximum dose of 10 Gy. To verify correct daily patient positioning before each treatment and to determine the daily treatment setup error after radiation delivery, axial CT scans were taken before and immediately after each treatment without moving the patient from the treatment position, for comparison with the planning CT scan. Toxicity was measured using the Common Toxicity Criteria, the Late Effects of Normal Tissue scoring system and a neurologic function scale. Follow-up was conducted 4 weeks after completion of SBRT, and then 2, 3, 6, 9, 12, and every 6 months thereafter.

RESULTS

The procedure was technically feasible to perform in all patients. No neurologic toxicity was observed in any patient. The median follow-up time was 9 months (range 6-16). The Clopper-Pearson upper bound on the probability of paralysis with 95% confidence is no greater than 0.181. The positional setup error was determined to be within 1 mm of planning isocenter.

CONCLUSIONS

This Phase I study shows that intensity-modulated, near simultaneous, CT image-guided SBRT is a feasible, and highly precise technique for the noninvasive treatment of spinal metastases. Although no paralysis has developed in the 15 patients treated, continued monitoring for spinal cord toxicity is warranted, as larger numbers of patients will be needed to more precisely define the upper bound on the probability of spinal cord myelopathy.

Power calculations for the transmission/disequilibrium and affected sib pair tests using elementary probability methods

The transmission/disequilibrium test (TDT) and the affected sib pair test (ASP) both test for the association of a marker allele with some conditions. Here, we present methods for calculating the probability of detecting the association (power) for a study examining a fixed number of families for suitability for the study and for calculating the number of such families to be examined. Both calculations use a genetic model for the association. The model considered posits a bi-allelic marker locus that is linked to a bi-allelic disease locus with a possibly nonzero recombination fraction between the loci. The penetrance of the disease is an increasing function of the number of disease alleles. The TDT tests whether the transmission by a heterozygous parent of a particular allele at a marker locus to an affected offspring occurs with probability greater than 0·5. The ASP tests whether transmission of the same allele to two affected sibs occurs with probability greater than 0·5. In either case, evidence that the probability is greater than 0·5 is evidence for association between the marker and the disease. Study inclusion criteria (IC) can greatly affect the necessary sample size of a TDT or ASP study. IC considered by us include a randomly selected parent at least one parent or both parents required to be heterozygous. It also allows a specified minimum number of affected offspring to be required (TDT only). We use elementary probability calculations rather than complex mathematical manipulations or asymptotic methods (large sample size approximations) to compute power and requisite sample size for a proposed study. The advantages of these methods are simplicity and generality.

High-dose therapy and autologous hematopoietic-cell transplantation for follicular lymphoma beyond first remission: the Stanford University experience

A retrospective analysis was performed to investigate the outcome of high-dose therapy (HDT) and autologous hematopoietic cell transplantation in patients with follicular lymphomas beyond first remission. Ninety-two patients with primary induction failure or relapsed follicular low-grade lymphoma (FLGL), follicular large cell lymphoma (FLCL), and transformed follicular lymphoma (TFL) were treated with myeloablative therapy consisting of etoposide (60 mg/kg), cyclophosphamide (100 mg/kg), and either carmustine (BCNU;15 mg/kg) or fractionated total body irradiation (FTBI; 1200 cGy) followed by transplantation of purged autologous bone marrow or peripheral blood hematopoietic cells. For the 49 patients with relapsed FLGL, the median age was 49 years and the median interval from diagnosis to HDT was 30 months. The 4-year estimate of overall survival (OS) was 60% (95% confidence interval [CI], 45%-75%) and of disease-free survival (DFS) was 44% (95% CI, 29%-59%). Treatment with the FTBI-containing HDT regimen was associated with significantly longer DFS (P = .04) and OS (P = .04) in our multivariate analysis. OS was also significantly longer among those treated with 3 or fewer chemotherapy regimens. For the 26 FLCL patients, the median age was 51 years and in 31% the indication for HDT was primary induction failure. For FLCL patients, the 4-year estimate of OS was 58% (95% CI, 37%-79%) and of DFS was 51% (95% CI, 30%-72%). Among the 17 patients with TFL, 13 (76%) transformed at first relapse, and only 6 patients (35%) achieved complete remission with salvage therapy prior to HDT. For TFL patients, the 4-year estimate of OS was 50% (95% CI, 24%-76%) and of DFS 49% (95% CI, 20%-78%). There were 3 occurrences of myelodysplasia (1 after treatment with TBI, 2 after BCNU treatment), yielding an estimated incidence of 7% (95% CI, 0%-16%) at 56 months. This analysis shows that relapsed FLGL patients treated with 3 or fewer different chemotherapy regimens show inferior survival. The HDT regimen containing FTBI appears to be superior to the BCNU-based regimen for relapsed FLGL, although longer follow-up is needed to evaluate late effects. Lastly, patients with TFL or induction failure and relapsed FLCL can achieve survival outcome comparable to those observed with the indolent follicular lymphomas.

Chronic disease self-management program: 2-year health status and health care utilization outcomes

OBJECTIVES

To assess the 1- and 2-year health status, health care utilization and self-efficacy outcomes for the Chronic Disease Self-Management Program (CDSMP). The major hypothesis is that during the 2-year period CDSMP participants will experience improvements or less deterioration than expected in health status and reductions in health care utilization.

DESIGN

Longitudinal design as follow-up to a randomized trial.

SETTING

Community.

PARTICIPANTS

Eight hundred thirty-one participants 40 years and older with heart disease, lung disease, stroke, or arthritis participated in the CDSMP. At 1- and 2-year intervals respectively 82% and 76% of eligible participants completed data.

MAIN OUTCOME MEASURES

Health status (self-rated health, disability, social/role activities limitations, energy/fatigue, and health distress), health care utilization (ER/outpatient visits, times hospitalized, and days in hospital), and perceived self-efficacy were measured.

MAIN RESULTS

Compared with baseline for each of the 2 years, ER/outpatient visits and health distress were reduced (P <0.05). Self-efficacy improved (P <0.05). The rate of increase is that which is expected in 1 year. There were no other significant changes.

CONCLUSIONS

A low-cost program for promoting health self-management can improve elements of health status while reducing health care costs in populations with diverse chronic diseases.

The Child Abuse Potential Inventory and pregnancy outcome in expectant adolescent mothers

OBJECTIVE

The study explores the prenatal Child Abuse Potential (pCAP) scores derived from the Child Abuse Potential Inventory administered to expectant adolescent mothers. The aim of the study was to assess the association of the pCAP scores with maternal negative prenatal behaviors, and evaluate the contribution of the pCAP scores to neonatal morbidity.

METHOD

The pCAP scores, demographic data, and self-report on prenatal behaviors were obtained during the second half of the pregnancy in a sample of 45 poor single adolescent mothers. A pediatrician blind to the prenatal data reviewed the neonatal records to assess neonatal morbidity. Maternal prenatal records were reviewed for obstetric risk assessment by an obstetrician who was blind to the rest of the data. The relations among the pCAP scores, prenatal behaviors, and neonatal morbidity were analyzed.

RESULTS

In the prenatal period, the pCAP scores were positively correlated with self-reported prenatal smoking and substance use. The multiple linear regression analysis showed that the pCAP scores significantly contributed to neonatal morbidity independently of obstetric risk factors.

CONCLUSIONS

The Child Abuse Potential scores obtained during pregnancy in poor single adolescent mothers reflect domains of maternal functioning that are associated with negative prenatal behaviors and appear to be important for predicting neonatal morbidity. Further studies are warranted to validate the prenatal use of the Child Abuse Potential Inventory.

Randomized trial addressing risk features and time factors of surgery plus radiotherapy in advanced head-and-neck cancer

PURPOSE

A multi-institutional, prospective, randomized trial was undertaken in patients with advanced head-and-neck squamous cell carcinoma to address (1) the validity of using pathologic risk features, established from a previous study, to determine the need for, and dose of, postoperative radiotherapy (PORT); (2) the impact of accelerating PORT using a concomitant boost schedule; and (3) the importance of the overall combined treatment duration on the treatment outcome.

METHODS AND MATERIALS

Of 288 consecutive patients with advanced disease registered preoperatively, 213 fulfilled the trial criteria and went on to receive therapy predicated on a set of pathologic risk features: no PORT for the low-risk group (n = 31); 57.6 Gy during 6.5 weeks for the intermediate-risk group (n = 31); and, by random assignment, 63 Gy during 5 weeks (n = 76) or 7 weeks (n = 75) for the high-risk group. Patients were irradiated with standard techniques appropriate to the site of disease and likely areas of spread. The study end points were locoregional control (LRC), survival, and morbidity.

RESULTS

Patients with low or intermediate risks had significantly higher LRC and survival rates than those with high-risk features (p = 0.003 and p = 0.0001, respectively), despite receiving no PORT or lower dose PORT, respectively. For high-risk patients, a trend toward higher LRC and survival rates was noted when PORT was delivered in 5 rather than 7 weeks. A prolonged interval between surgery and PORT in the 7-week schedule was associated with significantly lower LRC (p = 0.03) and survival (p = 0.01) rates. Consequently, the cumulative duration of combined therapy had a significant impact on the LRC (p = 0.005) and survival (p = 0.03) rates. A 2-week reduction in the PORT duration by using the concomitant boost technique did not increase the late treatment toxicity.

CONCLUSIONS

This Phase III trial established the power of risk assessment using pathologic features in determining the need for, and dose of, PORT in patients with advanced head-and-neck squamous cell cancer in a prospective, multi-institutional setting. It also revealed the impact of the overall treatment time in the combination of surgery and PORT on the outcome in high-risk patients and showed that PORT acceleration without a reduction in dose by a concomitant boost regimen did not increase the late complication rate. These findings emphasize the importance of coordinated interdisciplinary care in the delivery of combined surgery and RT.

Physical activity outcomes of CHAMPS II: a physical activity promotion program for older adults

BACKGROUND

Despite well-known benefits of physical activity for older adults, about two thirds are underactive. Community-based programs are needed to facilitate increased physical activity. We examine the effectiveness of CHAMPS II, an inclusive, choice-based physical activity promotion program to increase lifetime physical activity levels of seniors. CHAMPS guided participants to choose activities that took into account their health, preferences, and abilities. It offered information on ways for them to exercise safely, motivate themselves, overcome barriers, and develop a balanced exercise regimen.

METHODS

A 1-year randomized controlled trial was conducted with physically underactive seniors in a multispecialty group practice. Changes in self-reported physical activity by group were evaluated using ANCOVA, controlling for age and sex.

RESULTS

Of 173 randomized subjects, 164 (95%) completed the trial. Subjects were aged 65 to 90 years (M = 74, SD = 6); 66% were female. The intervention group increased estimated caloric expenditure by 487 calories/week in moderate (or greater) intensity activities (MET >/= 3.0; p <.001) and by 687 calories/week in physical activities of any intensity (p <.001). Control group changes were negligible. Between-group analyses found that the changes were significantly different in both measures (p values <.05). Overweight persons especially benefited from this program. The program was as effective for women, older adults (75+), and those who did not set aside time to exercise at baseline.

CONCLUSIONS

The program led to meaningful physical activity increases. Individually tailored programs to encourage lifestyle changes in seniors may be effective and applicable to health care and community settings.

The development of breast carcinoma in women with thyroid carcinoma

BACKGROUND

Breast carcinoma and thyroid carcinoma are two malignancies that occur most commonly in women. An association between the incidence rates of thyroid and breast carcinoma in women after a diagnosis of the other malignancy has been suggested in a retrospective analysis of a single institution's tumor registry. In that study, an increased incidence of breast carcinoma in premenopausal women previously treated for thyroid carcinoma was observed.

METHODS

The purpose of this study was to investigate further this relation utilizing a large database, the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) database. The SEER database is maintained by the National Cancer Institute, and it represents 11 population-based cancer registries covering approximately 14% of the United States population. The study was a population-based retrospective cohort analysis using external comparisons. From 1973 to 1994, 365 women in the SEER database were identified as having both thyroid and breast carcinomas. The SEER database from 1973 to 1994 was utilized to calculate age specific and calendar year specific incidence rates for each year for thyroid and breast carcinomas. The expected number of second cancers for each age group, calendar year, and follow-up period were determined by multiplying these incidence rates by the age specific and calendar year specific number of person-years at risk. The risk ratio (RR) was calculated by dividing the observed by the expected number of second cancers. Statistical significance was determined by the Poisson test.

RESULTS

A total of 1,333,115 person-years were available for analysis. One hundred thirteen thyroid carcinoma cases were diagnosed after breast carcinoma cases (RR, 0.99; P = 0.576). Two hundred fifty-two breast carcinoma cases were diagnosed after thyroid carcinoma cases (RR, 1.18; P = 0.007). Premenopausal women (age 20-49 years) with an index thyroid carcinoma have a significantly increased risk of developing subsequent breast carcinoma (RR, 1.42; P = 0.001). Black premenopausal women with an index thyroid carcinoma do not have an increased risk of developing breast carcinoma, but the statistical power is lower due to low numbers. No women with index breast carcinoma have an increased risk of developing thyroid carcinoma.

CONCLUSIONS

Women with a history of thyroid carcinoma have a greater than expected risk of developing breast carcinoma. This risk is most pronounced in premenopausal white women. The implications of this observation with respect to breast carcinoma screening guidelines and thyroid carcinoma treatment guidelines deserve further investigation.

Views of United States physicians and members of the American Medical Association House of Delegates on physician-assisted suicide

OBJECTIVE

To ascertain the views of physicians and physician leaders toward the legalization of physician-assisted suicide.

DESIGN

Confidential mail questionnaire.

PARTICIPANTS

A nationwide random sample of physicians of all ages and specialties, and all members of the American Medical Association (AMA) House of Delegates as of April 1996.

MEASUREMENTS

Demographic and practice characteristics and attitude toward legalization of physician-assisted suicide.

MAIN RESULTS

Usable questionnaires were returned by 658 of 930 eligible physicians in the nationwide random sample (71%) and 315 of 390 eligible physicians in the House of Delegates (81%). In the nationwide random sample, 44.5% favored legalization (16.4% definitely and 28.1% probably), 33.9% opposed legalization (20.4% definitely and 13.5% probably), and 22% were unsure. Opposition to legalization was strongly associated with self-defined politically conservative beliefs, religious affiliation, and the importance of religion to the respondent (P <.001). Among members of the AMA House of Delegates, 23.5% favored legalization (7.3% definitely and 16.2% probably), 61.6% opposed legalization (43.5% definitely and 18.1% probably), and 15% were unsure; their views differed significantly from those of the nationwide random sample (P <.001). Given the choice, a majority of both groups would prefer no law at all, with physician-assisted suicide being neither legal nor illegal.

CONCLUSIONS

Members of the AMA House of Delegates strongly oppose physician-assisted suicide, but rank-and-file physicians show no consensus either for or against its legalization. Although the debate is sometimes adversarial, most physicians in the United States are uncertain or endorse moderate views on assisted suicide.

The sample size for a clinical trial: a Bayesian-decision theoretic approach

Using decision theory, what is an appropriate sample size for a clinical trial, with a binary endpoint? We present a program, suitable for actual planning, which, with some extensions, implements Canner's solution to this question. Examples with a discussion are given. Implications of a Bayesian approach are discussed. Bayesian and Neyman--Pearson approaches are compared.

Treatment of acne vulgaris by biofeedback relaxation and cognitive imagery

A multielement intervention involving biofeedback-assisted relaxation and cognitive imagery treatment of acne vulgaris was investigated in this study with 30 patients receiving medical dermatological treatment. Patients were matched on age, sex, and pre-treatment acne severity and randomly assigned to groups. Treatment consisted of 12 sessions over six weeks and resulted in a significant reduction in acne severity as compared to the attention-comparison and medical control groups. Treatment group patients continuing home practice until follow-up maintained their gains, whereas those who discontinued failed to maintain gains.

Effect of high-dose cyclosporine on etoposide pharmacodynamics in a trial to reverse P-glycoprotein (MDR1 gene) mediated drug resistance

PURPOSE

The consequences of using cyclosporine (CsA) therapy to modulate P-glycoprotein-mediated multidrug resistance include increased myelosuppression, hyperbilirubinemia, and altered disposition of the cytotoxin. The purpose of this study was to analyze further the relationship between the degree of leukopenia, and etoposide pharmacokinetic factors.

METHODS

Each patient initially received intravenously-administered etoposide alone (150-200 mg/m2/d x 3). Later it was given in combination with CsA administered at escalating loading doses (range 2-7 mg/kg) as a 2 hour intravenous (IV) infusion followed by a 3 day continuous infusion, at doses ranging from 5 to 21 mg/ kg/day. Serial plasma etoposide concentration-time samples were assayed by high-performance liquid chromatography (HPLC). The area under the curve (AUC) of unbound etoposide was calculated from the total plasma etoposide AUC using a previous published equation [22] where % unbound etoposide = (1.4 x total bilirubin) - (6.8 x serum albumin) + 34.4. The percent decrease in white blood cell (WBC) count and the total or unbound etoposide AUC relationship was fitted to a sigmoid Emax model adapted for paired observations, where: % Decrease in WBC count =E(max) x PDRV(H+Z x delta)/(PDRV50 + Z x beta) + PDRVH + Z x delta In this equation, Z was the variable describing the two treatment groups (0 = no CsA and 1 = CsA). The fitted parameters were PDRV50, the pharmacodynamic response variable (PDRV) producing 50% of the maximal response; parameter beta, which describes the effect of the treatment group on the PDRV50; parameter H (Hill constant), which defines the slope of the response curve and parameter delta, which describes the effect of the treatment group on parameter H.

RESULTS

CsA at a median concentration of 1,938 microg/ml resulted in a median increase in the total plasma etoposide AUC by 103% and the calculated unbound plasma etoposide AUC by 104%. This paralleled a 12% greater median percent decrease in WBC count during etoposide + CsA treatment (72% vs. 84%, P = 0.03). The percent decrease in WBC count and total or unbound etoposide AUC relationship was fitted to the sigmoid Emax model. The model using the unbound etoposide AUC described the data adequately (r = 0.790) and was precise, with a mean absolute error of 6.4% (95% confidence interval: -4.9, 7.8). The fitted parameter-estimates suggested that at equivalent unbound etoposide AUC values above 10 microg x h/ml, the sigmoid Emax model predicted a 5% greater WBC count suppression when CsA was added to the treatment regimen.

CONCLUSION

These findings suggest that a small degree of the enhanced myelosuppression observed with CsA combined with etoposide might be attributable to inhibition of P-glycoprotein in bone marrow precursor cells. However, the majority of the effect observed appears to be due to pharmacokinetic interactions, which result in increases in unbound etoposide.

High-dose therapy and autologous bone marrow transplantation for follicular lymphoma in first complete or partial remission: results of a phase II clinical trial

Advanced stage follicular small cleaved and mixed cell lymphoma is characterized by relapse from remission and survival ranging from 6 to 12 years. Because young patients have the greatest compromise in longevity, the efficacy and toxicity of high-dose radiochemotherapy and bone marrow transplantation after conventional chemotherapy was evaluated in a prospective phase II clinical trial. Thirty-seven patients in a minimal disease state after conventional chemotherapy received fractionated total body irradiation and high-dose etoposide and cyclophosphamide, followed by purged autologous bone marrow. A reference sample of 188 patients of similar age, stage, and histology managed at this institution before 1988 was identified for comparison of patient characteristics and outcomes. Compared with reference patients, transplant recipients had a higher tumor burden at diagnosis. With a median follow-up of 6.5 years, the estimated 10-year survival after transplantation was 86%. There was a single lymphoma death yielding a 10-year disease-specific survival of 97%. There were 2 early transplant-related deaths and 2 late acute leukemia deaths. Ten patients relapsed, one with microscopic disease only. High tumor burden at diagnosis and incomplete response to chemotherapy adversely influenced survival in the reference but not in the transplanted patients. The estimated risk of death of 14% and relapse of 30% at 10 years in our transplanted follicular lymphoma patients, the majority of whom had high tumor burdens, compares favorably with our observations in appropriately matched reference patients.

Confirmatory serologic testing for acute toxoplasmosis and rate of induced abortions among women reported to have positive Toxoplasma immunoglobulin M antibody titers

OBJECTIVE

Results obtained with commercial testing kits for immunoglobulin M Toxoplasma antibodies may be inaccurate or may be inaccurately interpreted, which may influence whether a woman decides to terminate the pregnancy. This study was undertaken to determine whether confirmatory testing at a reference laboratory and communication of the results and an expert interpretation to the patient's physician would affect the rate of induced abortions among pregnant women with positive results of testing for immunoglobulin M Toxoplasma antibodies in outside laboratories.

STUDY DESIGN

This was a retrospective cohort study of 811 consecutive pregnant women for whom the toxoplasma serologic profile was performed at a reference laboratory. Almost all the patients had been informed by their physicians that a result of a test for immunoglobulin M Toxoplasma antibodies performed in an outside laboratory was positive. Women were separated into those with a toxoplasma serologic profile result suggestive of a recently acquired infection (group 1) and those with a result suggestive of an infection acquired in the more distant past (group 2). Physician reports of induced abortions were used to determine rates of induced abortion in groups 1 and 2.

RESULTS

Of the 811 women 321 (39.6%) were considered likely to have a recent infection (group 1) and 490 (60.4%) were considered likely to have a past infection (group 2). Physicians reported pregnancy outcomes for 433 (53.4%) of 811 women (65.1% and 45.7% in groups 1 and 2, respectively). Whereas 36 of 209 women in group 1 (17.2%) terminated the pregnancy, only 1 of 224 women in group 2 (0.4%) chose abortion (P <.001).

CONCLUSION

Confirmatory serologic testing in a reference laboratory and communication of the results and their correct interpretation by an expert to the patient's physician decreased the rate of unnecessary abortions by approximately 50% among women for whom positive immunoglobulin M Toxoplasma test results had been reported by outside laboratories.

Relationship of neurological function and age in older women. The study of osteoporotic fractures

The decline of neurological and neuromuscular function with age in older women and in subgroups of older women with selected risk factors for poor function is described using cross- sectional analyses of data on 8,080 women from the multicenter Study of Osteoporotic Fractures. All twelve performance-based tests of muscle strength, balance, gait, somatosensory discrimination and reaction time declined with increasing age. On a percentage scale, vibration threshold declined the most rapidly with age. Participants who were smokers, physically inactive, nonconsumers of alcohol, diabetics and more frequent fallers had poorer age-adjusted performance than those without these attributes. However, with a few exceptions, the rate of decline in performance with age for those with and without these characteristics did not differ significantly.

A review on reproduction in South American camelids

In this paper, aspects of reproductive physiology and endocrinology, as well as sexual behaviour in South American camelids are reviewed. Because of the many unique features of reproduction in these animals, the application of advanced breeding techniques that are routinely used in other domestic species has been slow and, in some cases, are not applicable. Relatively high embryonic loss and the capacity to carry only one offspring at a time limit production in females. Furthermore, some 20% of females do not conceive following mating. Research is needed to elucidate the causes of embryonic loss, particularly in relation to the preferential location of embryos in the left uterine horn and the apparent differential luteolytic activity of the two uterine horns. A fuller understanding of the endocrine changes and mechanisms accompanying folliculogenesis, estrus, induction of ovulation and luteal regression may led to treatments that provide better control of ovulation and enhance the quality and viability of eggs shed. In the male, the hormonal interactions involved in facilitating libido need to be established and the underlying causes of declining libido resulting from continued exposure to estrous females, identified. More importantly, there is a need to develop a routine method to collect semen from animals on farm, or in studs. Deficiencies in this area have long hampered the evaluation of sires through proper assessment of their semen quality and in the application of artificial insemination. In addition, establishment of techniques to freeze semen from these species has obvious advantages for breeding, including crossbreeding between species to improve products such as fibre and to assist in preservation of some of the more endangered New World camelids.

The production of transgenic domestic livestock: successes, failures and the need for nuclear transfer

The direct transfer of recombinant DNA to embryos is conceptually a powerful method for the manipulation of the genetic potential of domestic animals, but in practice the technology has yet to fulfil its promise. In this paper, two examples are given of research utilising direct genetic manipulation, both of which are aimed at increasing aspects of productivity in sheep. The first of these involves the modification of the growth hormone status of sheep by the use of the ovine growth hormone gene, the regulation of which has been altered by the use of an ovine metallothionein promoter. While there has been a large amount of research already conducted in this area by many groups, our recent results provide one of the first demonstrations that this approach can increase the growth rates of sheep while maintaining the animals in good health. The second project involves the modification of intermediary metabolism in sheep by the introduction of the cysteine biosynthetic pathway. The results to date demonstrate that it is possible to change intermediary metabolism in animals using our approach but that there are species-specific requirements that must be satisfied in order to make the approach a practical method for improving animal productivity.

Hazard function estimators: a simulation study

Kernel-based methods for the smooth, non-parametric estimation of the hazard function have received considerable attention in the statistical literature. Although the mathematical properties of the kernel-based hazard estimators have been carefully studied, their statistical properties have not. We reviewed various kernel-based methods for hazard function estimation from right-censored data and compared the statistical properties of these estimators through computer simulations. Our simulations covered seven distributions, three levels of random censoring, four types of bandwidth functions, two sample sizes and three types of boundary correction. We conducted a total of 504 simulation experiments with 500 independent samples each. Our results confirmed the advantages of two recent innovations in kernel estimation - boundary correction and locally optimal bandwidths. The median relative improvement (decrease) in mean square error over fixed-bandwidth estimators without boundary correction was 3 per cent for fixed-bandwidth estimators with left boundary correction, 52 per cent locally optimal bandwidths without boundary correction, and 66 per cent for locally optimal bandwidths with left boundary correction. The locally optimal bandwidth estimators with left boundary correction also outperformed three previously published and publicly available algorithms, with median relative improvements in mean square error of 31 per cent, 77 per cent and 80 per cent.

Asymptotic power calculations: description, examples, computer code

This paper describes two asymptotic methods for sample size and power calculation for hypothesis testing. Both methods assume that the distribution of the likelihood ratio is approximately distributed as a central chi(2) distribution under the null hypothesis and as a non-central chi(2) under the alternative hypothesis. The approximation to the non-centrality parameter differs between the methods. It is shown how these methods can be automatically extended from constraints setting parameters to constant values to constraints positing equality of parameters. Two very simple examples are presented; one demonstrates that the information method can produce arbitrarily incorrect results. Four more comprehensive examples are then discussed. In addition to demonstrating the wide range of applicability of these methods, the examples illustrate techniques that may be used in cases in which there is insufficient initial information available to perform a realistic calculation. The availability of a computer implementation of these methods in S-plus is announced, as are routines for computing the cumulative distribution function of the non-central chi(2) and its inverse.

Impact of prophylactic immediate posttransplant ganciclovir on development of transplant atherosclerosis: a post hoc analysis of a randomized, placebo-controlled study

BACKGROUND

Coronary artery disease occurs in an accelerated fashion in the donor heart after heart transplantation (TxCAD), but the cause is poorly understood. The risk of developing TxCAD is increased by cytomegalovirus (CMV) infection and decreased by use of calcium blockers. Our group observed that prophylactic administration of ganciclovir early after heart transplantation inhibited CMV illness, and we now propose to determine whether this therapy also prevents TxCAD.

METHODS AND RESULTS

One hundred forty-nine consecutive patients (131 men and 18 women aged 48+/-13 years) were randomized to receive either ganciclovir or placebo during the initial 28 days after heart transplantation. Immunosuppression consisted of muromonab-CD3 (OKT-3) prophylaxis and maintenance with cyclosporine, prednisone, and azathioprine. Mean follow-up time was 4.7+/-1.3 years. In a post hoc analysis of this trial designed to assess efficacy of ganciclovir for prevention of CMV disease, we compared the actuarial incidence of TxCAD, defined by annual angiography as the presence of any stenosis. Because calcium blockers have been shown to prevent TxCAD, we analyzed the results by stratifying patients according to use of calcium blockers. TxCAD could not be evaluated in 28 patients because of early death or limited follow-up. Among the evaluable patients, actuarial incidence of TxCAD at follow-up (mean, 4.7 years) in ganciclovir-treated patients (n=62) compared with placebo (n=59) was 43+/-8% versus 60+/-10% (P<0.1). By Cox multivariate analysis, independent predictors of TxCAD were donor age >40 years (relative risk, 2.7; CI, 1.3 to 5.5; P<0.01) and no ganciclovir (relative risk, 2.1; CI, 1.1 to 5.3; P=0.04). Stratification on the basis of calcium blocker use revealed differences in TxCAD incidence when ganciclovir and placebo were compared: no calcium blockers (n=53), 32+/-11% (n=28) for ganciclovir versus 62+/-16% (n=25) for placebo (P<0.03); calcium blockers (n=68), 50+/-14% (n=33) for ganciclovir versus 45+/-12% (n=35) for placebo (P=NS).

CONCLUSIONS

TxCAD incidence appears to be lower in patients treated with ganciclovir who are not treated with calcium blockers. Given the limitations imposed by post hoc analysis, a randomized clinical trial is required to address this issue.

Evidence suggesting that a chronic disease self-management program can improve health status while reducing hospitalization: a randomized trial

OBJECTIVES

This study evaluated the effectiveness (changes in health behaviors, health status, and health service utilization) of a self-management program for chronic disease designed for use with a heterogeneous group of chronic disease patients. It also explored the differential effectiveness of the intervention for subjects with specific diseases and comorbidities.

METHODS

The study was a six-month randomized, controlled trial at community-based sites comparing treatment subjects with wait-list control subjects. Participants were 952 patients 40 years of age or older with a physician-confirmed diagnosis of heart disease, lung disease, stroke, or arthritis. Health behaviors, health status, and health service utilization, as determined by mailed, self-administered questionnaires, were measured.

RESULTS

Treatment subjects, when compared with control subjects, demonstrated improvements at 6 months in weekly minutes of exercise, frequency of cognitive symptom management, communication with physicians, self-reported health, health distress, fatigue, disability, and social/role activities limitations. They also had fewer hospitalizations and days in the hospital. No differences were found in pain/physical discomfort, shortness of breath, or psychological well-being.

CONCLUSIONS

An intervention designed specifically to meet the needs of a heterogeneous group of chronic disease patients, including those with comorbid conditions, was feasible and beneficial beyond usual care in terms of improved health behaviors and health status. It also resulted in fewer hospitalizations and days of hospitalization.

Production of sheep embryos in vitro and development of progeny following single and twin embryo transfers

An in vitro culture system for producing ovine embryos is described, in which heat inactivated sheep serum was used as a protein source for maturation, fertilization and 7-d culture phases. Ovaries obtained from a commercial abattoir were used as the source of mature ewe (285) and lamb oocytes (356), which were subsequently cultured in this system to yield similar mean cleavage rates of 91 and 92%, respectively, but significantly different (P < 0.025) proportions for blastocysts/cleaved oocytes (46 and 18%). At Days 7 or 8 of culture, embryos from each source were transferred, either singly (ewe-derived) or in pairs (ewe- and lamb-derived), to hormonally synchronized recipient ewes, resulting in the birth of lambs ranging in weight from 2.5 to 8.8 kg for singletons and 2.6 to 8.0 kg for twins. Mean gestation length of 153.4 +/- 0.5 d (range 151 to 160) was slightly longer than the expected norm of about 150 d. The pregnancy rate was significantly higher after the transfer of embryo pairs (64%) than single (39%) embryos, while survival of lambs to weaning was greater for singleton (80%) than for twin lambs (43%). Some factor(s) in the culture media, such as growth factors in the sera, may have a mitogenic effect on embryonic cells, or it may alter the distribution of cells to the trophectoderm and inner cell mass, resulting in enhanced body growth rates.

Neonatal immunization against gonadotropin-releasing hormone (GnRH) results in diminished GnRH secretion in adulthood

The effects of neonatal immunization against GnRH were studied in sheep after they had reached adulthood (3-4 yr) and the antibody titers had fallen to undetectable levels. The immunized animals had small gonads, and the females did not have large follicles (>3 mm) or corpora lutea in their ovaries. Compared with controls, the immunized animals had low or nondetectable levels of LH and FSH in peripheral plasma, and the immunized animals generally failed to respond to a single i.v. GnRH challenge. After ovariectomy, the control ewes, but not the immunized ewes, showed an elevation in plasma LH and FSH levels. The sampling of hypophysial portal blood, with a newly described method, showed that the secretion of GnRH was reduced in the immunized animals, but the amount of GnRH in the median eminence was similar in the control and immunized ewes. The pituitary content of LH and FSH was reduced in the immunized ewes as was messenger RNA for the gonadotropin subunits and the GnRH receptor. These data indicate that neonatal immunization does not affect the synthesis of GnRH in adulthood but reduces the secretion of GnRH, causing long-term sterility in these animals.

Methods of correcting for multiple testing: operating characteristics

We examine the operating characteristics of 17 methods for correcting p-values for multiple testing on synthetic data with known statistical properties. These methods are derived p-values only and not the raw data. With the test cases, we systematically varied the number of p-values, the proportion of false null hypotheses, the probability that a false null hypothesis would result in a p-value less than 5 per cent and the degree of correlation between p-values. We examined the effect of each of these factors on family-wise and false negative error rates and compared the false negative error rates of methods with an acceptable family-wise error. Only four methods were not bettered in this comparison. Unfortunately, however, a uniformly best method of those examined does not exist. A suggested strategy for examining corrections uses a succession of methods that are increasingly lax in family-wise error. A computer program for these corrections is available.

Early reconstitution of immunity and decreased severity of herpes zoster in bone marrow transplant recipients immunized with inactivated varicella vaccine

Varicella-zoster virus (VZV) causes herpes zoster after bone marrow transplantation (BMT). The immunogenicity of heat-inactivated varicella vaccine and effects on VZV pathogenesis were evaluated in 75 BMT patients randomized to receive vaccine or no intervention. Among 14 patients given a single dose at 1 month after transplantation, the mean (+/-SE) stimulation index (SI) was 12.20 +/- 3.13 compared with 4.83 +/- 2.74 (P = .036) in 14 unvaccinated patients, but clinical disease was not altered. Among 24 patients vaccinated at 1, 2, and 3 months, mean SI was 8.43 +/- 3.89 versus 2.00 +/- 0.33 (P = .014) in 23 unvaccinated patients at 4 months and 8.56 +/- 2.81 versus 5.30 +/- 2.47 (P = .043) at 5 months. Disease severity associated with VZV reactivation was decreased dramatically in vaccinees given three doses; severity scores were 6.4 +/- 1.0 versus 11.8 +/- 1.1 (P = .007). This experience with varicella vaccine in BMT patients is the first evidence that active immunization can reduce morbidity due to herpesvirus reactivation in high-risk populations.

Genotype selection to rapidly breed congenic strains

Congenic strains can now be constructed guided by the transmission of DNA markers. This allows not only selection for transmission of a desired, donor-derived differential region but also selection against the transmission of unwanted donor origin genomic material. The additional selection capacity should allow congenic strains to be produced in fewer generations than is possible with random backcrosses. Here, we consider modifications of a standard backcross breeding scheme to produce congenic mice by the inclusion of genotype-based selective breeding strategies. Simulation is used to evaluate the consequences of each strategy on the number of chromosomes that contain unwanted, donor-derived genetic material and the average length of this unwanted donor DNA for each backcross generation. Our prototypic strategy was to choose a single mouse to sire each generation using criteria designed to select against the transmission of chromosomes, other than the one containing the replacement genomic region, that contain any donor origin sequence at all. This chromosome elimination strategy resulted in an average of 16.4 chromosomes free of donor DNA in mice of the third backcross (N3) generation. A strategy based solely on positive selection for the replacement region required six backcross generations to achieve the same results.

Stanford-Kaiser Permanente G1 study for clinical stage I to IIA Hodgkin's disease: subtotal lymphoid irradiation versus vinblastine, methotrexate, and bleomycin chemotherapy and regional irradiation

PURPOSE

We have demonstrated that a relatively mild chemotherapy regimen, vinblastine, methotrexate, and bleomycin (VBM), and involved-field radiotherapy (IFRT) could substitute for extended-field radiotherapy in patients with favorable Hodgkin's disease (HD) who have been laparotomy-staged. The purpose of this study is to determine if VBM and regional radiotherapy can substitute for extended-field radiotherapy in favorable clinical stage (CS) I and II HD.

PATIENTS AND METHODS

Seventy-eight patients with favorable CS I to II HD were randomly assigned to subtotal lymphoid irradiation (STLI) or VBM chemotherapy and regional radiotherapy. Randomization was stratified on the basis of age, sex, number of Ann Arbor sites, histology, and institution. Patients were evaluated for freedom from progressive HD, survival, and toxicity. Results were compared with the predecessor trial in pathologically staged patients.

RESULTS

With a median follow-up period of 4 years, the rate of freedom from progressive HD was 92% (95% confidence interval [CI], 88% to 96%) for patients treated with STLI and 87% (95% CI, 81% to 93%) for patients treated with VBM and regional radiotherapy. Six of seven patients who relapsed are alive and in remission following successful second-line therapy.

CONCLUSION

Given the caveat of a small number of patients, the results of extended-field radiotherapy and VBM and regional radiotherapy are comparable with a median follow-up period of 4 years. VBM serves as a paradigm to reduce late effects in favorable early-stage HD. We do not advocate its routine use in clinical practice, but instead encourage participation in clinical trials with the objective of maintaining efficacy while reducing toxicity in CS I and II HD.

A pilot randomized controlled study on the effect of laser photocoagulation of confluent soft macular drusen

PURPOSE

The authors determined the effect of photocoagulation of drusen on visual acuity and progression to subretinal neovascular membranes (SRNV).

METHODS

One of paired eyes was randomized to photocoagulation with other eye to control in 27 patients having symmetrical maculopathy and visual acuities, aged 46 to 81 years (mean, 69.7 years); follow-up 1 to 6 years (mean, 3.2 years).

RESULTS

Final visual acuity was improved in treated eye or decreased in control eye in 12 patients, equal in 13 patients, and decreased in treated eye in 2 patients (P < 0.006). Progression to SRNV was less with treatment.

CONCLUSION

Laser photocoagulation of confluent soft macular drusen may improve long-term visual prognosis.

The effect of incomplete knowledge of parameter values on single- and multiple-stage designs for logistic regression

We consider the design of single- and multiple-stage dose-response trials in which the probability of response is a logistic function of the dose. Knowledge of the parameters of the logistic at the time of planning the trial is represented by a Gaussian prior distribution. Methods are presented for determining a design that approximately optimizes a measure of the accuracy of estimation averaged over the prior distribution. Changes in design due to uncertainty of parameter values are described as well as the changes in sample size required to produce a specified precision. In multiple-stage trials, the initial stage is planned as if it were the only stage. For succeeding stages, the initial Gaussian prior distribution is updated using outcomes at the previous stages. At each such stage, the design optimizes a chosen criterion averaged over the updated prior distribution. The effectiveness of this methodology is evaluated by comparing the operating characteristics of two-stage designs with those of single-stage designs.

High-dose therapy and autologous hematopoietic progenitor cell transplantation for recurrent or refractory Hodgkin's disease: analysis of the Stanford University results and prognostic indices

One hundred nineteen patients with relapsed or refractory Hodgkin's disease (HD) received high-dose therapy followed by autologous hematopoietic progenitor cell transplantation. Three preparatory regimens, selected on the basis of prior therapy and pulmonary status, were employed. Twenty-six patients without a history of prior chest or pelvic irradiation were treated with fractionated total body irradiation, etoposide (VP) 60 mg/kg and cyclophosphamide (Cy) 100 mg/kg. Seventy-four patients received BCNU 15 mg/kg with identical doses of VP and Cy. A group of 19 patients with a limited diffusing capacity or history of pneumonitis received a novel high-dose regimen consisting of CCNU 15 mg/kg, VP 60 mg/kg and Cy 100 mg/kg. Twenty-nine patients (24%) had failed induction therapy and 35 (29%) had progressive HD within 1 year of initial chemotherapy. At 4 years actuarial survival was 52%, event-free survival was 48% and freedom from progression (FFP) was 62%. No significant differences were seen in survival data with the three preparatory regimens. Six patients died within 100 days of transplantation and 5 died at a later date of transplant-related complications. Secondary malignancies have developed in 6 patients, including myelodysplasia/leukemia in four patients and solid tumors in two patients. Regression analysis identified systemic symptoms at relapse, disseminated pulmonary or bone marrow disease at relapse and more than minimal disease at the time of transplantation as significant prognostic factors for overall and event-free survival and FFP. Patients with none of these factors enjoyed an 85% FFP at 4 years compared with 41% for patients with one or more unfavorable prognostic factors (P = .0001). Our results confirm the efficacy of high-dose therapy and autografting in recurrent or refractory HD. Although longer follow-up is necessary to address ultimate cure rates and toxicity, our data indicate that a desire to reduce late effects should drive future research efforts in favorable patients whereas new initiatives are needed for those with less favorable prognoses.

Assessing changes in the impact of cancer on population survival without considering cause of death

BACKGROUND

We have previously argued against the calculation of cancer-specific death rates as philosophically undefined and biased. Deaths attributed to cancer during a particular year occur in patients diagnosed during an unknown distribution of past times, so cancer-specific death rates cannot be used to assess changes in the impact of cancer on survival of the population at specific periods of diagnosis.

PURPOSE

Our goal was to develop and analyze three measures of the impact of cancer on population survival that do not use the attributed cause of death: 1) the age-adjusted proportion of the population diagnosed with cancer in a particular year and projected to be dead of any cause by a particular age; 2) the same measure corrected for population mortality; and 3) the expected years of life lost to a 20-year-old individual because of the possibility of a diagnosis of cancer.

METHODS

Data on all adults diagnosed with any cancer during the period from January 1973 through December 1990 were obtained from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. The measures were calculated separately for various combined sex and race groups. Three 2-year diagnosis periods spaced 5 years apart were considered: 1975-1976, 1980-1981, and 1985-1986. A statistical model was used to extrapolate survival beyond observation; the same model was used for patients diagnosed in the three time periods to minimize the effect of possible model misspecification on changes.

RESULTS

Cancer incidence increased for three of the four sex-race groups; age-adjusted changes from 1975 through 1976 to 1985 through 1986 were +11.5% for white men, +6.9% for white women, +15.1% for black men, and -9.2% for black women. Human immunodeficiency virus (HIV)-related cancers were responsible for an increased cancer incidence at early ages in white men in the latest time period studied. There was a decrease in the incidence of gynecologic cancers at early ages; the decrease was greater among black women (-55.1%) than among white women (-39.3%). Age- and incidence-adjusted 5-year survival increased by 17.9% for white men, 2.3% for white women, and 7.4% for black men and decreased by 14.1% for black women. When the data from 1985 through 1986 were compared with those from 1975 through 1976, the expected number of years lost to a 20-year-old individual because of cancer changed as follows for the various sex-race groups: +1.4% for white men (-4.0% if HIV-related cancers were not included in the calculation), +2.1% for white women, +12.2% for black men, and +8.8% for black women.

CONCLUSIONS

For white men and women, there has been an increase in both the incidence of and survival following the diagnosis of cancer; the two effects nearly cancel in our measures. The experience of black men and women has worsened because of increasing incidence or decreased survival.

Comparison between normal tissue reactions and local tumor control in head and neck cancer patients treated by definitive radiotherapy

PURPOSE

This study was conducted to test for the relationship between tumor and normal tissue radiosensitivity, by comparing local tumor control to the severity of acute and late normal tissue reactions in head and neck cancer patients treated by definitive radiotherapy.

METHODS AND MATERIALS

Two hundred eighty-six patients with head and neck cancer who were treated at the University of Texas M. D. Anderson Cancer Center between 1983 and 1993 were selected for the study. Of these, 124 (43%) were treated by a concomitant boost regimen and 162 (57%) by hyperfractionation. All patients had at least 1 year of follow-up. The tumor stage distribution according to the 1992 American Joint Committee on Cancer (AJCC) staging system was as follows: T1, 3%; T2, 53%; T3, 40%; T4, 4%. The average doses delivered were 71.2 Gy and 76.2 Gy for the concomitant boost and hyperfractionation regimens, respectively, with no significant variation between patients. Acute and late reactions were recorded using the Radiation Therapy Oncology Group (RTOG)/European Organization for Research on Treatment of Cancer (EORTC) grading system (0 to 4). The median follow-up period was 38 months (range: 12-107 months). The time to local tumor recurrence was analyzed in relation to the severity of acute and late reactions expressed as the maximum recorded grades, and to the time intensity of acute mucositis, expressed as the area under the curve of mucositis grade vs. time. Univariate and multivariate analyses also included T stage, N stage, and site of origin as other prognostic variables, and were carried out using a proportional hazards model.

RESULTS

Fifty-four patients (19%) suffered local failure. T stage was found to significantly influence local control (p = 0.009). There was a nonsignificant trend for higher failure rates in patients with maximum Grade 1 or 2 vs. those with Grade 3 or 4 acute mucositis (28 and 18%, respectively; p = 0.17). No correlation was found between the severity of late reactions and local tumor control after radiotherapy. Analysis by time intensity of mucositis revealed a wide variation between individuals with a nonsignificant trend for higher local failure rates in patients with low mucositis time intensity scores.

CONCLUSIONS

These clinical results suggest a possible relationship between normal tissue and tumor radiosensitivity. However, additional studies with a larger numbers of patients, and using refined normal tissue endpoints that incorporate a time function are needed to fully elucidate this question.

Influence of preparatory regimen and source of hematopoietic cells on outcome of autotransplantation for non-Hodgkin's lymphoma

The use of high-dose chemotherapy with or without total-body irradiation (TBI) followed by autologous hematopoietic cell transplantation is associated with improved survival for relapsed or refractory non-Hodgkin's lymphoma (NHL). Previous reports comparing preparatory regimens with or without TBI followed by autologous bone marrow transplantation (ABMT) or peripheral blood progenitor cell transplantation (PBPCT) for these patients did not demonstrate any survival difference between the different modalities. No randomized studies comparing survival for patients with NHL transplanted with radiochemotherapy vs. chemotherapy alone have been reported. We treated 221 patients with high-risk, relapsed or refractory NHL with either chemotherapy alone or radiochemotherapy followed by ABMT or PBPCT. The patients were assigned preparatory regimens in a non-randomized manner and this analysis was performed to evaluate differences in outcome with the two preparatory regimens. Actuarial five-year event-free survival (EFS) was similar in patients receiving fractionated total-body irradiation (FTBI) plus etoposide (VP-16) and cyclophosphamide (Cy) compared with chemotherapy alone consisting of carmustine (BCNU) plus identical doses of VP-16 and Cy (52% vs. 46%, p = 0.08). Overall survival (OS) favored radiochemotherapy (61%) compared with chemotherapy alone (53%, p = 0.02). The relapse rate was the same in both groups (41%), whereas the transplantation-related mortality (TRM) was similar in patients receiving chemotherapy alone and those receiving radiochemotherapy (13% vs. 7% respectively, p = 0.30). Proportional hazards analysis of significant variables including preparatory regimen found only the number of prior relapses to be predictive of EFS. Fewer number of prior relapses, radiochemotherapy and PBPCT were significant predictors of favorable OS. In additional analyses, the improved OS of the radiochemotherapy regimen was confirmed only for patients receiving ABMT but was not a significant predictor of outcome in patients transplanted with PBPCT. From these retrospective data we conclude: 1) PBPCT resulted in survival superior to that of ABMT; 2) the risk of relapse is similar with either preparatory regimen; 3) patients with fewer prior relapses enjoyed superior overall and event-free survival as well as fewer relapses; and 4) there were no significant differences in the two preparatory regimens when combined with PBPCT in relapsed or refractory NHL.

Polymorphism of adhesion molecule CD31 and its role in acute graft-versus-host disease

BACKGROUND

Graft-versus-host disease (GVHD) caused by poorly defined minor (i.e., other than HLA) histocompatibility antigens remains a serious problem in recipients of bone marrow transplants. We sought to determine whether the CD31 adhesion molecule is a minor alloantigen.

METHODS

We directly sequenced samples of complementary DNA (cDNA) encoding CD31 molecules from 21 unrelated normal subjects. Sequence-specific primers were then designed to amplify alleles by the polymerase chain reaction, thereby permitting CD31 typing of genomic DNA from additional normal subjects. To assess the relevance of CD31 matching to bone marrow transplantation, we performed CD31 typing of 46 recipients of bone marrow (32 without GVHD and 14 with severe [grade III or IV] acute GVHD) and their HLA-identical sibling donors. The immunoreactivity of CD31 phenotypes with anti-CD31 monoclonal antibodies was compared by flow cytometry.

RESULTS

Direct sequencing of cDNA for CD31 from the 21 normal subjects identified a single polymorphism, CTG-->GTG (Leu-->Val), at codon 125; we designated the resulting alleles CD31.L and CD31.V, respectively. The CD31 genotypes of these and 142 other unrelated subjects were of the expected frequencies. Among the transplant recipients, 71 percent of those with acute GVHD had CD31 genotypes that were not identical to the donor's genotype, as compared with 22 percent of the recipients without GVHD (P = 0.004). The binding of anti-CD31 monoclonal antibodies as measured by fluorescence-activated cell sorting correlated with the CD31 types of homozygous cell lines.

CONCLUSIONS

The adhesion molecule CD31 is polymorphic. When donor and recipient genotypes are not identical, the risk of GVHD increases. Prospective CD31 typing may reduce the risk of acute GVHD.

Evidence for genetic regulation of susceptibility to toxoplasmic encephalitis in AIDS patients

The frequency of HLA-DQ antigens in AIDS patients with toxoplasmic encephalitis (TE) were examined. HLA-DQ3 was significantly more frequent in white North American AIDS patients with TE (85.0%) than in the general white population (51.8%; P = .007, corrected P = .028) or randomly selected control AIDS patients who had not developed TE (40.0%; P = .016). In contrast, the frequency of HLA-DQ1 was lower in TE patients than in healthy controls (40.0% vs. 66.5%, P = .027), but this difference did not reach statistical significance when corrected for the number of variables tested (corrected P = .108 for the general white population). HLA-DQ3 thus appears to be a genetic marker of susceptibility to development of TE in AIDS patients, and DQ1 may be a resistance marker. These HLA associations with disease indicate that development of TE in AIDS patients is affected by a gene or genes in the HLA complex and that HLA-DQ typing may help in decisions regarding TE prophylaxis.

A randomized controlled trial of a computer-based physician workstation in an outpatient setting: implementation barriers to outcome evaluation

OBJECTIVE

A research prototype Physician Workstation (PWS) incorporating a graphical user interface and a drug ordering module was compared with the existing hospital information system in an academic Veterans Administration General Medical Clinic. Physicians in the intervention group received recommendations for drug substitutions to reduce costs and were alerted to potential drug interactions. The objective was to evaluate the effect of the PWS on user satisfaction, on health-related outcomes, and on costs.

DESIGN

A one-year, two-period, randomized controlled trial with 37 subjects.

MEASUREMENTS

Differences in the reliance on noncomputer sources of information, in user satisfaction, in the cost of prescribed medications, and in the rate of clinically relevant drug interactions were assessed.

RESULTS

The study subjects logged onto the workstation an average of 6.53 times per provider and used it to generate 2.8% of prescriptions during the intervention period. On a five-point scale (5 = very satisfied, 1 = very dissatisfied), user satisfaction declined in the PWS group (3.44 to 2.98 p = 0.008), and increased in the control group (3.23 to 3.72, p < 0.0001).

CONCLUSION

The intervention physicians did not use the PWS frequently enough to influence information-seeking behavior, health outcomes, or cost. The study design did not determine whether the poor usage resulted from satisfaction with the control system, problems using the PWS intervention, or the functions provided by the PWS intervention. Evaluative studies should include provisions to improve the chance of successful implementation as well as to yield maximum information if a negative study occurs.

Prognostic importance of intimal thickness as measured by intracoronary ultrasound after cardiac transplantation

BACKGROUND

Although intracoronary ultrasound (ICUS) has been validated for the early detection of transplant coronary artery disease (TxCAD), the prognostic importance of findings detected by this new imaging technique is unknown.

METHODS AND RESULTS

This study examined the relation of clinical outcome in 145 heart transplant recipients (mean age, 45.1 +/- 11.1 years) with the amount of intimal thickness measured by ICUS during routine annual coronary angiography 1 to 10 years (mean, 3.1 +/- 2.2 years) after transplantation. From published autopsy data, a mean intimal thickness of > 0.3 mm was considered significant. During a mean follow-up time of 48.2 +/- 10.2 months, 23 deaths (12 cardiac) occurred, and 6 patients required retransplantation. Angiographic TxCAD developed in 22 of 125 patients (17.6%) in the subgroup with normal angiograms at the time of ICUS and a follow-up annual angiographic study. In the total population and the subgroup, mean intimal thicknesses of > 0.3 and < or = 0.3 mm, respectively, were associated with significantly inferior 4-year actuarial overall survival (73% versus 96%, P = .005; 72% versus 92%, P = .05), cardiac survival (79% versus 96%, P = .005; 80% versus 98%, P = .04), and freedom from cardiac death and retransplantation (74% versus 98%, P < .0001; 70% versus 96%, P = .001). In addition, ICUS predicted freedom from development of subsequent angiographic TxCAD in the subgroup that was initially normal (26% versus 72%, P = .02). A mean intimal thickness by ICUS of > 0.3 mm was associated with inferior clinical outcome regardless of the presence of angiographic TxCAD and predicted the development of subsequent angiographic TxCAD. Despite significantly longer duration after transplantation, higher rejection incidence, and lower average daily cyclosporine dose, none of these covariates were independent risk factors for outcome.

CONCLUSIONS

These findings confirm the prognostic importance of mean intimal thickening of > 0.3 mm in heart transplant recipients and suggest that these patients should be candidates for early interventional strategies.