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Satisfaction with surgery outcomes and the decision process in a population-based sample of women with breast cancer.

OBJECTIVE: To better understand medical decision making in the context of "preference sensitive care," we investigated factors associated with breast cancer patients' satisfaction with the type of surgery received and with the decision process. DATA SOURCES/DATA COLLECTION: For a population-based sample of recently diagnosed breast cancer patients in the Detroit and Los Angeles metropolitan areas (N=1,633), demographic and clinical data were obtained from the Surveillance, Epidemiology, and End Results tumor registry, and self-reported psychosocial and satisfaction data were obtained through a mailed survey (78.4 percent response rate). STUDY DESIGN: Cross-sectional design in which multivariable logistic regression was used to identify sociodemographic and clinical factors associated with three satisfaction measures: low satisfaction with surgery type, low satisfaction with the decision process, and decision regret. PRINCIPAL FINDINGS: Overall, there were high levels of satisfaction with both surgery and the decision process, and low rates of decision regret. Ethnic minority women and those with low incomes were more likely to have low satisfaction or decision regret. In addition, the match between patient preferences regarding decision involvement and their actual level of involvement was a strong indicator of satisfaction and decision regret/ambivalence. While having less involvement than preferred was a significant indicator of low satisfaction and regret, having more involvement than preferred was also a risk factor. Women who received mastectomy without reconstruction were more likely to report low satisfaction with surgery (odds ratio [OR]=1.54, p<.05), low satisfaction with the process (OR=1.37, p<.05), and decision regret (OR=1.55, p<.05) compared with those receiving breast conserving surgery (BCS). An additional finding was that as patients' level of involvement in the decision process increased, the rate of mastectomy also increased (p<.001). CONCLUSIONS: A significant proportion of breast cancer patients experience a decision process that matches their preferences for participation, and report satisfaction with both the process and the outcome. However, women who report more involvement in the decision process are significantly less likely to receive a lumpectomy. Thus, increasing patient involvement in the decision process will not necessarily increase use of BCS or lead to greater satisfaction. The most salient aspect for satisfaction with the decision making process is the match between patients' preferences and experiences regarding participation.

Aged↗

Clinical significance of portal lymphoid aggregates/follicles in Chinese patients with chronic hepatitis C.

OBJECTIVE: Portal lymphoid aggregates/follicles (lymphoid A/F) is a characteristically histological finding in patients with chronic hepatitis C. We assessed the prevalence of lymphoid A/F in Chinese patients with chronic hepatitis C and evaluated the correlation of this phenomenon with clinical, biochemical, immunological, virological, and other histological features of these patients. METHODS: Eighty-nine Chinese patients with chronic hepatitis C were enrolled and portal lymphoid A/F was evaluated in liver biopsy. Clinical, biochemical, immunological, histological, and virological data, including serum HCV RNA titer and HCV genotype and the response to interferon therapy, were compared between patients with and without portal lymphoid A/F. RESULTS: Twenty-nine (33%) of 89 patients with chronic hepatitis C had portal lymphoid A/F. Patients with lymphoid A/F had a significantly higher frequency of HCV genotype 1b infection (p = 0.039) and had a significantly higher mean score of bile duct damage, periportal necroinflammation, and portal inflammation in liver histologies when compared with patients without lymphoid A/F. No significant difference in sex distribution, mean age, history of blood transfusion, serum liver biochemistry, presence of serum autoantibodies/cryoglobulinemia, serum viral titer, and response to interferon therapy was noted between the two groups. Multivariate logistic regression analysis showed HCV genotype 1b infection and periportal necroinflammation were significant independent predictors associated with portal lymphoid A/F. CONCLUSIONS: The presence of portal lymphoid A/F in Chinese patients with chronic hepatitis C was significantly correlated with HCV genotype 1b infection and periportal necroinflammation.

Biopsy↗

Study protocol: SPARCLE--a multi-centre European study of the relationship of environment to participation and quality of life in children with cerebral palsy.

BACKGROUND: SPARCLE is a nine-centre European epidemiological research study examining the relationship of participation and quality of life to impairment and environment (physical, social and attitudinal) in 8-12 year old children with cerebral palsy. Concepts are adopted from the International Classification of Functioning, Disability and Health which bridges the medical and social models of disability. METHODS/DESIGN: A cross sectional study of children with cerebral palsy sampled from total population databases in 9 European regions. Children were visited by research associates in each country who had been trained together. The main instruments used were KIDSCREEN, Life-H, Strength and Difficulties Questionnaire, Parenting Stress Index. A measure of environment was developed within the study. All instruments were translated according to international guidelines. The potential for bias due to non response and missing data will be examined. After initial analysis using multivariate regression of how the data captured by each instrument relate to impairment and socio-economic characteristics, relationships between the latent traits captured by the instruments will then be analysed using structural equation modelling. DISCUSSION: This study is original in its methods by directly engaging children themselves, ensuring those with learning or communication difficulty are not excluded, and by studying in quantitative terms the crucial outcomes of participation and quality of life. Specification and publication of this protocol prior to analysis, which is not common in epidemiology but well established for randomised controlled trials and systematic reviews, should avoid the pitfalls of data dredging and post hoc analyses.

Cerebral Palsy↗

[Interferon treatment of chronic hepatitis C--assessment of predictive factors to the effect of interferon treatment using multivariate analysis with the logistic regression model].

We treated 156 chronic hepatitis C patients with alpha-interferon (IFN) and assessed the response rate and the predictive factors to the effect of IFN treatment. Complete response (CR) rate was 39.1%, and CR with serum HCV-RNA disappearance rate was 29%. CR to IFN treatment was dependent on HCV serotype and serum HCV-RNA. Patients of serotype II and low serum HCV-RNA were effective to IFN treatment.

Adult↗

Comparison of famciclovir and lamivudine in the long-term treatment of hepatitis B infection after liver transplantation.

BACKGROUND: Preliminary results of short-term famciclovir and lamivudine therapy in patients with hepatitis B virus (HBV) infection after liver transplantation revealed promising results. In a retrospective study the efficacy of long-term treatment with these substances was compared. METHODS: A total of 53 HBV-infected adults (48 reinfections and 7 de novo infections) received antiviral treatment. A total of 32 of these patients were treated with famciclovir 3x500 mg, 20 of them were later switched to lamivudine. Fourteen patients received lamivudine, 150 mg/day orally, as first line therapy and 7 patients after failure of famciclovir-prophylaxis. Follow-up time was 8 to 62 months (mean 35 months). Response to therapy (HBV-DNA negative) was compared using Kaplan-Meier estimates. Potential influence factors (HBV-DNA and HBeAg pretransplant, HDV coinfection, pretreatment with famciclovir and immunosuppression) on treatment response were analyzed by log. Rank test (univariate); then a multivariate analysis (Cox multiple stepwise regression model) was applied. RESULTS: A total of 19 and 76% of the patients treated with famciclovir and lamivudine resp. became HBV-DNA negative; 0 and 24% HBsAg negative. Lamivudine was also effective as second line therapy. In a multivariate analysis of all 73 treatment courses, lamivudine treatment and HDV-coinfection were significant factors for better treatment response; regarding only the lamivudine group, negative HBeAg pretransplant was significant. Viral breakthrough after prolonged treatment occurred in 55% (lamivudine) to 80% (famciclovir) of treatment courses but was only accompanied by mild hepatitis. CONCLUSIONS: Lamivudine and famciclovir are potent drugs for the treatment of HBV-infection after liver transplantation. The antiviral capacity of lamivudine is superior even after pretreatment with famciclovir but after prolonged treatment viral breakthrough is often observed.

2-Aminopurine↗

Regression models and risk estimation for mixed discrete and continuous outcomes in developmental toxicology.

Multivariate dose-response models have recently been proposed for developmental toxicity data to simultaneously model malformation incidence (a binary outcome), and reductions in fetal weight (a continuous outcome). In this and other applications, the binary outcome often represents a dichotomization of another outcome or a composite of outcomes, which facilitates analysis. For example, in Segment II developmental toxicology studies, multiple malformation types (i.e., external, visceral, skeletal) are evaluated on each fetus; malformation status may also be ordinally measured (e.g., normal, signs of variation, full malformation). A model is proposed is for fetal weight and multiple malformation variables measured on an ordinal scale, where the correlations between the outcomes and between the offspring within a litter are taken into account. Fully specifying the joint distribution of outcomes within a litter is avoided by specifying only the distribution of the multivariate outcome for each fetus and using generalized estimating equation methodology to account for correlations due to litter clustering. The correlations between the outcomes are required to characterize joint risk to the fetus, and are therefore a focus of inference. Dose-response models and their application to quantitative risk assessment are illustrated using data from a recent developmental toxicology experiment of ethylene oxide in mice.

Abnormalities, Drug-Induced↗

Statistical modeling of dose-response relationships in clinical trials--a case study.

This paper presents a model-based assessment of the relationship between the dose of a test treatment and response. The data set used in the analysis describes the results of two clinical trials that were designed to assess the dose-response relationship of a test treatment. The models described in the paper are fit using weighted regression as implemented by the SAS procedure CATMOD. Relationships between weighted regression and other similar procedures are discussed.

Anticholesteremic Agents↗

HLA-DR2, a marker for class I antigen sensitization.

After analysis of 423 hemodialysis patients in a transfusion program and 461 cadaver-donor renal transplants, we found that HLA-DR2 frequency was significantly higher in the responder (36%) than in the nonresponder patient group (19%), according to the percentage of PRA (panel reactive antibodies). Among DR2+ patients, the percentage of hypersensitized patients was twice that of DR2- patients. Graft survival curves in cadaver-donor renal transplants indicated a significantly lower survival when recipients were DR2+, even in recipient-donor pairs identical for class II antigens but mismatched for class I antigens. The prognostic probability of low response to transfusions by a stepwise logistic regression analysis showed the influence of sex and DR2 phenotype. By multivariant discriminant analysis, we found that the DR2 phenotype was one of the most influential transfusion sensitization risk factors. Our preliminary conclusion is that DR2 can be related to immune responsiveness to class I antigens.

Antilymphocyte Serum↗

Physicians, pharmaceutical sales representatives, and the cost of prescribing.

OBJECTIVE: To evaluate the influence of primary care physicians' attitudes toward and use of information provided by pharmaceutical representatives on prescribing costs in ambulatory practice. DESIGN: A mailed questionnaire collected information about physician demographic and practice characteristics and attitudes toward and use of information provided by pharmaceutical representatives. PARTICIPANTS: Kentucky physicians practicing primary care adult medicine (family medicine, general practice, general medicine; n = 1603). MAIN OUTCOME MEASURE: Relative cost of prescribing, based on physician responses to treatment choices for ambulatory clinical scenarios in primary care. A multivariable regression model assessed predictive relationships between independent variables and prescription costs. RESULTS: Four hundred forty-six returned questionnaires were suitable for analysis. No significant differences were noted in age, gender, days worked per week, or years since graduation between responders and a sample of nonresponders. A significant positive correlation was found between physician cost of prescribing and perceived credibility, availability, applicability, and use of information provided by pharmaceutical representatives (P < .01, Pearson's Product-Moment Correlation Coefficient). Physicians in academic or hospital-based practice settings had significantly lower prescribing costs than physicians in nonacademic and nonhospital practices (P = .001, analysis of variance). Frequency of use of information provided by pharmaceutical representatives (P = .01, multiple linear regression) and the group practice setting (P = .02, multiple linear regression) remained significant, independent positive predictors of cost in the multivariable regression model. CONCLUSIONS: Frequency of use of information provided by pharmaceutical representatives and the group practice, nonacademic and nonhospital setting may be associated with increased primary care physician prescribing costs.

Attitude of Health Personnel↗

Diffusion of innovative approaches to managing hypoplastic left heart syndrome.

OBJECTIVE: To study the perceptions of outcome and the diffusion into practice of innovative approaches such as palliative surgery and heart transplantation to treat hypoplastic left heart syndrome. DESIGN: A forced-choice questionnaire was sent to 108 US neonatology section heads. Responses were analyzed using Wilcoxon matched pairs, chi 2 analysis, and multivariant logistic regression. RESULTS: Ninety-three questionnaires (86%) were returned. All respondents discussed palliative surgery or transplantation or both with parents; 71 (76%) of 93 also discussed comfort care. Nineteen (24%) of 80 recommended comfort care only, 51 (64%) of 80 recommended surgery only, and 10 (12%) of 80 recommended both. Of the 61 respondents recommending one or both surgical procedures, palliative surgery was recommended by 44 and transplantation by 33. Respondents perceived that transplantation was associated with a lower 1-year mortality than palliative surgery (P < .001) and with a better quality of life (P < .001). CONCLUSIONS: Palliative surgery and transplantation are widely used to treat hypoplastic left heart syndrome. The continued availability of comfort care suggests that these surgical procedures are still in transition from experimental technology to standard of care.

Cardiac Surgical Procedures↗

Acute promyelocytic leukemia. Therapy results and prognostic factors.

From December 1976 to July 1986, 34 patients with acute promyelocytic leukemia (APL) were treated with daunorubicin (DNR) alone and simultaneous supportive therapy with low-dose heparin, platelet transfusions, and fresh frozen plasma. Two consecutive maintenance therapy regimens were employed in patients who achieved complete remission (CR): (1) a classical maintenance with methotrexate and 6-mercaptopurine, with DNR plus methyl-GAG re-inductions; (2) from 1982 an intensive sequential combination therapy regimen was administered. CR was achieved in 23 patients (68%). Only one patient had leukemic resistance. Other failures were a consequence of post-chemotherapy complications. A multivariate logistic regression analysis has been performed to evaluate the prognostic importance on response to remission induction of 25 patient and disease characteristics at diagnosis. The significant variables in decreasing order of significance were: serum albumin level, fever at diagnosis, serum creatinine level, and age. The median duration of remission and survival by Kaplan-Meier analysis were projected to be 24 and 25 months, respectively. Relapses occurred in 11 of 23 CR patients. Nine patients remained in the first remission from 5+ to 37+ months. Short-term (CR) and long-term results (duration of remission and survival) in APL treated for induction with DNR alone were similar to those obtained in other subtypes of acute myeloblastic leukemia by intensive combination chemotherapy.

Adolescent↗

Perceptions of interethnic group racism predict increased vascular reactivity to a laboratory challenge in college women.

African-Americans have disproportionately higher rates of hypertension than any other U.S. ethnic group. Researchers have postulated that the psychosocial-stress association with racism may help explain these higher rates in African-Americans, as well as blood pressure variability among African-Americans. Using a quasi-experimental design, this study examined the relationship between perceived interethnic group racism (racism) and blood pressure responses in 39 African-American females. Measurements of blood pressure were obtained before, during, and after a laboratory challenge where participants spoke about their personal views and feelings concerning animal rights. Perceptions of racism, as well as psychological and coping responses to racism, were assessed via the Perceived Racism Scale. The results revealed that on average, participants perceived racism 75.25 times/year. Racist statements were perceived most often, and speaking up was the most frequently reported coping response. The overwhelming majority of participants (76.47%) used active and passive coping responses to deal with racism. Among the psychological responses to racism, the magnitude of emotional responding was greatest for anger. Multivariate regression analyses indicated that perceived racism was significantly and positively related to diastolic blood pressure changes during the speech (p = .01), early recovery (p < .003), and late recovery (p = .01) periods. Potential confounders did not mitigate these effects. The findings highlight the importance of delineating the role of more real-world behavioral challenges in future research exploring blood pressure variability and hypertension risk in African-Americans.

Adaptation, Psychological↗

Therapeutic thresholds in methadone maintenance treatment: a receiver operating characteristic analysis.

Twenty-four-hour trough (R)- and (R,S)-methadone plasma concentrations were measured on 94 methadone maintenance treatment (MMT) patients classified as 'responders' or 'non-responders', based on urine toxicology evidence of recent illicit opiate use. Receiver operating characteristic (ROC) curves for daily dose, dose/bodyweight, and (R)- and (R,S)-methadone trough plasma concentrations were used to identify optimal thresholds; areas under the curve (AUC) were used to compare predictive power. Non-responders (n=37) had a lower mean dose (73 mg/day versus 147 mg/day; p<0.001), (R)-methadone concentration (136 ng/ml versus 223 ng/ml; p<0.005) and (R,S)-methadone concentration (266 ng/ml versus 409 ng/ml; p=0.001) than responders. On multivariate regression, duration of treatment and methadone dose were significantly associated with treatment response. After backward stepwise regression, each year of treatment increased the odds of abstinence from illicit opioid use by 34% (OR 1.34; 95% CI 1.14-1.57)); each 20mg of methadone dose by 36% (OR 1.36 CI; 95% CI 1.11-1.67). On ROC analysis, AUC for daily dose (0.77, 95% CI 0.68-0.87), dose/bodyweight (0.76, 95% CI 0.66-0.85), (R)-methadone (0.73, 95% CI 0.63-0.84) and (R,S)-methadone concentration (0.70, 95% CI 0.59-0.81) did not differ significantly. Dose/bodyweight, and trough plasma concentrations of (R)- or (R,S)-methadone were no better predictors of treatment response than daily dose, and did not improve the fit of the model for treatment outcome as judged by the likelihood ratio test (p=0.21, 0.88, and 0.97, respectively). Optimal therapeutic thresholds (sensitivity, specificity) were: daily dose 100mg/day (67%, 81%); (R)-methadone 200 ng/ml (51%, 78%); (R,S)-methadone 400 ng/ml (40%, 81%). Thresholds with specificity near 90% (dose 140 mg/day; (R)-methadone 250 ng/ml; (R,S)-methadone 500 ng/ml) may help guide dose titration for patients continuing to use illicit opiates.

Adult↗

Sex and diagnostic evaluation of possible coronary artery disease after exercise treadmill testing at one academic teaching center.

Controversy exists as to whether a sex bias exists that affects the diagnostic approach to suspected coronary artery disease: previous studies have used coronary angiography, but not other noninvasive testing, as a primary end point. This investigation examined posttest sex differences in diagnostic evaluation after exercise treadmill testing according to a broader end point than just coronary angiography alone. The design was a cohort analytic study with a 90-day follow-up. The study was done at the Cleveland Clinic Foundation, an academic group practice. Patients included consecutive adults (1023 men and 579 women) with chest pain but no documented coronary disease who were referred for symptom-limited exercise treadmill testing without adjunctive imaging; none had undergone prior invasive cardiac procedures. Main outcome measures included (1) performance of any subsequent diagnostic study (invasive or noninvasive) and (2) performance of coronary angiography as the next diagnostic study. During follow-up, 89 (8.7%) men and 48 (8.3%) women underwent a second diagnostic study (odds ratio 0.95; 95% confidence interval 0.66 to 1.37; p > 0.8), whereas 64 (6.3%) men and 21 (3.6%) women went straight to coronary angiography (odds ratio 0.56; 95% confidence interval 0.34 to 0.93; p = 0.02). In multivariable logistic regression analyses, which considered baseline clinical characteristics, the ST-segment response, and other prognostically important exercise responses, women tended to be less likely than men to be referred to any second test (adjusted odds ratio 0.70; 95% confidence interval 0.42 to 1.19; p > 0.1) but were markedly and significantly less likely to be referred straight to coronary angiography (adjusted odds ratio 0.33; 95% confidence interval 0.17 to 0.65). After exercise treadmill testing, women were only slightly less likely than men to be referred for subsequent diagnostic testing; they were, however, much less likely to be referred straight to coronary angiography as opposed to another noninvasive study.

Academic Medical Centers↗

Long-term survival following neoadjuvant chemotherapy and radical surgery in locally advanced cervical cancer.

The aim of this study was to analyse the long-term survival and the relationships between prognostic factors at presentation, chemoresponsiveness and disease outcome in patients with locally advanced cervical cancer treated by neoadjuvant chemotherapy and radical surgery (RS). Two consecutive studies of neoadjuvant chemotherapy containing cisplatin, bleomycin plus/minus methotrexate followed by radical hysterectomy and systematic aortic and pelvic lymphadenectomy were carried out between January 1986 and September 1990 on 130 patients with > or = 4 cm stage IB2-III cervical cancer. Survival analysis was performed using the Kaplan and Meier test and Cox's multivariate regression analysis. 128 (98%) of the patients enrolled were evaluable for clinical response and survival, 83% (106) of the patients responded to chemotherapy, with a 15% complete response rate. Logistic regression analysis demonstrated that International Federation of Gynecology and Obstetrics (FIGO) stage, cervical tumour size, parametrial involvement and histotype are highly predictive of response. Responding patients underwent laparotomy, but 8% were not amenable for radical surgery. The 10-year survival estimates were 91%, 80% and 34.5% for stage IB2-IIA bulky, IIB and III, respectively (P < 0.001). After Cox's regression analysis, the parameters significantly associated with survival were the same factors predicting response to neoadjuvant chemotherapy. No stage IB2-IIA bulky patient has so far relapsed, while 12% stage IIB and 56% stage III patients recurred. The 10-year disease-free survival estimates are 91% and 44% for stage IB2-IIB and III, respectively (P < 0.001). Metastatic nodes and persistent tumour in the parametria were the only two independent factors for disease-free survival after multiple regression analysis. After a long-term follow-up (median follow-up 98 months (20-129+)), our results give new evidence of the prognostic value of response to neoadjuvant chemotherapy and of a possible therapeutic benefit of the sequential treatment adopted which, however, must be verified in a randomised setting.

Adult↗

Reduced expression of BAX is associated with poor prognosis in patients with epithelial ovarian cancer: a multifactorial analysis of TP53, p21, BAX and BCL-2.

Traditional clinicopathological features do not predict which patients will develop chemotherapy resistance. The TP53 gene is frequently altered in ovarian cancer but its prognostic implications are controversial. Little is known on the impact of TP53-downstream genes on prognosis. Using molecular and immunohistochemical analyses we examined TP53 and its downstream genes p21, BAX and BCL-2 in ovarian tumour tissues and have evaluated the results in relation to clinico-pathological parameters, clinical outcome and response to platinum-based chemotherapy. Associations of tested factors and patient and tumour characteristics were studied by Spearman rank correlation and Pearsons chi2 test. The Cox proportional hazard model was used for univariate and multivariate analysis. The associations of tested factors with response was tested using logistic regression analysis. TP53 mutation, p21 and BCL-2 expression were not associated with increased rates of progression and death. Expression of TP53 was associated with a shorter overall survival only (relative hazard rate [RHR] 2.01, P = 0.03). Interestingly, when combining TP53 mutation and expression data, this resulted in an increased association with overall survival (P = 0.008). BAX expression was found to be associated with both progression-free (RHR 0.44, P = 0.05) and overall survival (RHR 0.42, P = 0.03). Those patients who simultaneously expressed BAX and BCL-2 had a longer progression-free and overall survival compared to patients whose tumours did not express BCL-2 (P = 0.05 and 0.015 respectively). No relations were observed between tested factors and response to platinum-based chemotherapy. We conclude that BAX expression may represent a prognostic indicator for patients with ovarian cancer and that the combined evaluation of BAX and BCL-2 may provide additional prognostic significance.

Adult↗

An outbreak of gastrointestinal illness and erythema nodosum from grated carrots contaminated with Yersinia pseudotuberculosis.

BACKGROUND: Outbreaks of Yersinia pseudotuberculosis infection have been epidemiologically linked to fresh produce, but the bacterium has not been recovered from the food items implicated. In May 2003, a cluster of gastrointestinal illness and erythema nodosum was detected among schoolchildren who had eaten lunches prepared by the same institutional kitchen. METHODS: We conducted a case-control study and trace-back, environmental, and laboratory investigations. Case patients had culture-confirmed Y. pseudotuberculosis O:1 infection, erythema nodosum, or reactive arthritis. Bacterial isolates from clinical and environmental samples were compared using pulsed-field gel electrophoresis (PFGE). RESULTS: Of 7392 persons at risk, 111 (1.5%) met the case definition; 76 case patients and 172 healthy control subjects were enrolled in the case-control study. Only raw grated carrots were significantly associated with illness in a logistic-regression model (multivariable odds ratio, 5.7 [95% confidence interval, 1.7-19.5]); a dose response was found for increasing amount of consumption. Y. pseudotuberculosis O:1 isolates from 39 stool specimens and from 5 (42%) of 12 soil samples that contained carrot residue and were obtained from peeling and washing equipment at the production farm were indistinguishable by PFGE. CONCLUSIONS: Carrots contaminated early in the production process caused a large point-source outbreak. Our findings enable the development of evidence-based strategies to prevent outbreaks of this emerging foodborne pathogen.

Adolescent↗

Prognostic value of B-cell mitogen-induced and spontaneous thymidine uptake in vitro in chronic B-lymphocytic leukaemia cells.

Blood lymphocytes from 50 patients with chronic B-lymphocytic leukaemia (B-CLL) were cultured in vitro with and without the polyclonal B-cell activators (PBA) dextran sulphate (DxS), lipopolysaccharide from E. coli (LPS), and Epstein Barr virus (EBV). Patients with blood lymphocytes that showed a high spontaneous or PBA-induced 3H-thymidine uptake in 4 d cultures had a significantly shorter therapy-free survival than patients whose lymphocytes showed a low thymidine uptake. The DxS-induced cellular thymidine uptake was the most powerful predictor of prognosis. Eighteen patients with leukaemic cells responding to DxS stimulation had a median therapy-free survival of 17 months and a probability of 5 year therapy-free survival of less than 0.1, whereas for 30 patients with DxS unresponsive cells the corresponding figures were greater than 120 months and greater than 0.7, respectively (log rank, P less than 0.0001). A multivariate Cox's regression analysis revealed that the DxS-induced leukaemic cell response was of greater prognostic importance than clinical features such as blood counts and staging according to Rai and Binet. Therefore PBA-induced leukaemic cell thymidine uptake seems valuable in the prediction of prognosis in B-CLL.

Adult↗