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Background: In trials designed to estimate rates of perinatal mother to child transmission of HIV, HIV assays are scheduled at multiple points in time. Still, infection status for some infants at some time points may be unknown, particularly when interim analyses are conducted., Methods: Logistic regression models are commonly used to estimate covariate-adjusted transmission rates, but their methods for handling missing data may be inadequate. Here we propose using coarsened multinomial regression models to estimate cumulative and conditional rates of HIV transmission. Through simulation, we compare the proposed models to standard logistic models in terms of bias, mean squared error, coverage probability, and power. We consider a range of treatment effect and visit process scenarios, while including imperfect sensitivity of the assay and contamination of the endpoint due to early breastfeeding transmission. We illustrate the approach through analysis of data from a clinical trial designed to prevent perinatal transmission., Results: The proposed cumulative and conditional models performed well when compared to their logistic counterparts. Performance of the proposed cumulative model was particularly strong under scenarios where treatment was assumed to increase the risk of in utero transmission but decrease the risk of intrapartum and overall perinatal transmission and under scenarios designed to represent interim analyses. Power to estimate intrapartum and perinatal transmission was consistently higher for the proposed models., Conclusion: Coarsened multinomial regression models are preferred to standard logistic models for estimation of perinatal mother to child transmission of HIV, particularly when assays are missing or occur off-schedule for some infants.

Background: Poor nutrition may be associated with mother-to-child transmission (MTCT) of HIV and other adverse pregnancy outcomes., Objective: The objective was to examine the relation of nutritional indicators with adverse pregnancy outcomes among HIV-infected women in Tanzania, Zambia, and Malawi., Design: Body mass index (BMI; in kg/m(2)) and hemoglobin concentrations at enrollment and weight change during pregnancy were prospectively related to fetal loss, neonatal death, low birth weight, preterm birth, and MTCT of HIV., Results: In a multivariate analysis, having a BMI < 21.8 was significantly associated with preterm birth [odds ratio (OR): 1.82; 95% CI: 1.34, 2.46] and low birth weight (OR: 2.09; 95% CI: 1.41, 3.08). A U-shaped relation between weight change during pregnancy and preterm birth was observed. Severe anemia was significantly associated with fetal loss or stillbirth (OR: 3.67; 95% CI: 1.16, 11.66), preterm birth (OR: 2.08; 95% CI: 1.39, 3.10), low birth weight (OR: 1.76; 95% CI: 1.07, 2.90), and MTCT of HIV by the time of birth (OR: 2.26; 95% CI: 1.18, 4.34) and by 4-6 wk among those negative at birth (OR: 2.33; 95% CI: 1.15, 4.73)., Conclusions: Anemia, poor weight gain during pregnancy, and low BMI in HIV-infected pregnant women are associated with increased risks of adverse infant outcomes and MTCT of HIV. Interventions that reduce the risk of wasting or anemia during pregnancy should be evaluated to determine their possible effect on the incidence of adverse pregnancy outcomes and MTCT of HIV.

Purpose: To develop a new calcium score for use with unenhanced cardiac computed tomography (CT) that can be used to define the percentage of coronary arteries affected by calcium and to correlate this score with risk factors and cardiovascular events., Materials and Methods: Institutional review boards at all participating centers approved this HIPAA-compliant study, and all participants gave written informed consent. Calcium coverage score (CCS), which represents the percentage of coronary arteries affected by calcific plaque, was calculated for 3252 participants in the Multi-Ethnic Study of Atherosclerosis in whom calcific plaque was detected with CT. Quasi-Poisson models were used to estimate associations (assessed by using t tests with robust standard errors) between CCS and risk factors. Associations between the CCS, Agatston, and calcium mass scores (hereafter, mass scores) and outcomes were estimated and assessed by using Cox proportional hazards models with Wald tests. The predictive ability of these models was assessed by using area under the receiver operating characteristic curves and bootstrap t tests., Results: After adjustments were made for age, race, ethnicity, and sex in the quasi-Poisson model, CCS was associated with hypertension, dyslipidemia, and diabetes (P < .001 for all diseases). After adjustments for age and sex, a twofold increase in CCS was associated with a 52% (95% confidence interval: 34%, 72%) increase in risk for any coronary heart disease (CHD) event. When Agatston or mass scores were included with CCS in a Cox model for prediction of CHD events, neither Agatston score nor mass score was a significant predictor, whereas CCS remained significantly associated with CHD events. Although receiver operating characteristic curves suggested that there was a difference between CCS score and Agatston and mass scores in prediction of a cardiac event, no differences in prediction of hard cardiac events (myocardial infarction, death) were found., Conclusion: Both spatial distribution and amount of calcified plaque contribute to risk for CHD., ((c) RSNA, 2008.)

Objective: To describe the incidence and predictors of stillbirth in a predominantly human immunodeficiency virus (HIV)-infected African cohort., Methods: Human Immunodeficiency Virus (HIV) Prevention Trials Network (HPTN) 024 was a randomized controlled trial of empiric antibiotics to reduce chorioamnionitis-related perinatal HIV transmission. A proportion of HIV-uninfected individuals were enrolled to reduce community-based stigma surrounding the trial. For this analysis, only women who gave birth to singleton infants were included., Results: Of 2,659 women enrolled, 2,434 (92%) mother- child pairs met inclusion criteria. Of these, 2,099 (86%) infants were born to HIV-infected women, and 335 (14%) were born to HIV-uninfected women. The overall stillbirth rate was 32.9 per 1,000 deliveries (95% confidence interval [CI] 26.1-40.7). In univariable analyses, predictors for stillbirth included previous stillbirth (odds ratio [OR] 2.3, 95% CI 1.2-4.3), antenatal hemorrhage (OR 14.4, 95% CI 4.3-47.9), clinical chorioamnionitis (OR 20.9, 95% CI 5.1-86.2), and marked polymorphonuclear infiltration on placental histology (OR 2.9, 95% CI 1.7-5.2). When compared with pregnancies longer than 37 weeks, those at 34-37 weeks (OR 1.7, 95% CI 0.8-3.4) and those at less than 34 weeks (OR 22.8, 95% CI 13.6-38.2) appeared more likely to result in stillborn delivery. Human immunodeficiency virus infection was not associated with a greater risk for stillbirth in either univariable (OR 1.5, 95% CI 0.7-3.0) or multivariable (adjusted OR 1.11, 95% CI 0.38-3.26) analysis. Among HIV-infected women, however, decreasing CD4 cell count was inversely related to stillbirth risk (P=.009)., Conclusion: In this large cohort, HIV infection was not associated with increased stillbirth risk. Further work is needed to elucidate the relationship between chorioamnionitis and stillbirth in African populations., Clinical Trial Registration: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00021671, Level of Evidence: II.

Background: Much of the burden of morbidity affecting women of childbearing age in sub-Saharan Africa occurs in the context of HIV-1 infection. Understanding patterns of illness and determinants of disease in HIV-1-infected mothers may guide effective interventions to improve maternal health in this setting., Methods: We describe the incidence and cofactors of comorbidities affecting peripartum and postpartum HIV-1-infected women in Kenya. Women were evaluated by clinical examination and standardized questionnaires during pregnancy and for up to 2 years after delivery., Results: Five hundred thirty-five women were enrolled in the cohort (median CD4 count of 433 cells/mm) and accrued 7736 person-months of follow-up. During 1-year follow-up, the incidence of upper respiratory tract infections was 161 per 100 person-years, incidence of pneumonia was 33 per 100 person-years, incidence of tuberculosis (TB) was 11 per 100 person-years, and incidence of diarrhea was 63 per 100 person-years. Immunosuppression and HIV-1 RNA levels were predictive for pneumonia, oral thrush, and TB but not for diarrhea; CD4 counts <200 cells/mm(3) were associated with pneumonia (relative risk [RR] = 2.87, 95% confidence interval [CI]: 1.71 to 4.83), TB (RR = 7.14, 95% CI: 2.93 to 17.40) and thrush. The risk of diarrhea was significantly associated with crowding (RR = 1.86, 95% CI: 1.19 to 2.92) and breast-feeding (RR = 1.71, 95% CI: 1.19 to 2.44). Less than 10% of women reported hospitalization during 2-year follow-up; mortality risk in the cohort was 1.9% and 4.8% for 1 and 2 years, respectively., Conclusions: Mothers with HIV-1, although generally healthy, have substantial morbidity as a result of common infections, some of which are predicted by immune status or by socioeconomic factors. Enhanced attention to maternal health is increasingly important as HIV-1-infected mothers transition from programs targeting the prevention of mother-to-child transmission to HIV care clinics.

Objective: To evaluate the relationship between fetal fibronectin and preterm birth and maternal-to-child transmission of human immunodeficiency virus (HIV) in an African population of predominantly HIV-infected women., Methods: During a trial of second trimester and intrapartum antibiotics compared with placebo to prevent chorioamnionitis and reduce preterm birth and mother-to-child transmission of HIV, vaginal fluid was collected before antibiotics (20-24 weeks) and after treatment at 28 weeks and assayed for fetal fibronectin. Pregnancy outcomes of 2,353 women delivering liveborn singleton infants are presented., Results: Positive fetal fibronectin assays (50 ng/mL or more) were detected in 4.2% and 4.9% of samples at 20-24 weeks and 28 weeks. Positive fetal fibronectin assays at 28 weeks but not at 20-24 weeks were associated with lower mean birthweight (199 g, P<.001); lower mean gestational age (2 weeks, P<.001); six-fold higher rate of preterm birth less than 32 weeks (10.8% compared with 1.9%, odds ratio 6.3, 95% confidence interval 3.2-12.3) and a two-fold higher rate of preterm birth less than 37 weeks (38.7 compared with 22.0%, odds ratio 2.3, 95% confidence interval 1.5-3.3). Also, at 28 weeks, as the fetal fibronectin values increased, each of the outcomes worsened, and every test of trend was significant. An association between elevated fetal fibronectin levels and mother-to-child transmission of HIV was present at 20 to 24 weeks but not at 28 weeks. Antibiotic treatment at 20 to 24 weeks was not associated with fetal fibronectin levels at 28 weeks., Conclusion: In a population of predominantly HIV- infected African women, fetal fibronectin concentrations at 28 but not at 20-24 weeks were associated with increased risk of preterm birth. The associations were stronger for early preterm birth and when fetal fibronectin levels were higher. High levels of fetal fibronectin were positively associated with mother-to-child transmission of HIV at 20 -24 but not at 28 weeks. Antibiotic treatment did not influence fetal fibronectin levels., Clinical Trial Registration: www.clinicalTrials.gov, NCT00021671, Level of Evidence: I.

Background: There is conflicting evidence regarding the effects of breast-feeding on maternal mortality from human immunodeficiency virus type 1 (HIV-1) infection, and little is known about the effects of breast-feeding on markers of HIV-1 disease progression., Methods: HIV-1-seropositive women were enrolled during pregnancy and received short-course zidovudine. HIV-1 RNA levels and CD4 cell counts were determined at baseline and at months 1, 3, 6, 12, 18, and 24 postpartum and were compared between breast-feeding and formula-feeding mothers., Results: Of 296 women, 98 formula fed and 198 breast-fed. At baseline, formula-feeding women had a higher education level and prevalence of HIV-1-related illness than did breast-feeding women; however, the groups did not differ with respect to CD4 cell counts and HIV-1 RNA levels. Between months 1 and 24 postpartum, CD4 cell counts decreased 3.9 cells/ microL/month (P<.001), HIV-1 RNA levels increased 0.005 log(10) copies/mL/month (P=.03), and body mass index (BMI) decreased 0.03 kg/m(2)/month (P<.001). The rate of CD4 cell count decline was higher in breast-feeding mothers (7.2 cells/ microL/month) than in mothers who never breast-fed (4.0 cells/ microL/month) (P=.01). BMI decreased more rapidly in breast-feeding women (P=.04), whereas HIV-1 RNA levels and mortality did not differ significantly between breast-feeding and formula-feeding women., Conclusions: Breast-feeding was associated with significant decreases in CD4 cell counts and BMI. HIV-1 RNA levels and mortality were not increased, suggesting a limited adverse impact of breast-feeding in mothers receiving extended care for HIV-1 infection.

Objective: Histologic chorioamnionitis has been associated with preterm birth and low birthweight. Our goal was to evaluate the relationship between polymorphonuclear cell and mononuclear cell placental infiltrations and adverse infant outcomes., Study Design: Data from women who were enrolled in a trial of antibiotics for prevention of mother-to-child transmission of HIV-1 and of preterm birth were analyzed. Women who had HIV and women who did not have HIV were assigned randomly to either metronidazole 250 mg and erythromycin 250 mg at 20 to 24 weeks of gestation 3 times daily for 7 days and metronidazole 250 mg and ampicillin 500 mg every 4 hours during labor or identical placebos. Women with HIV were offered nevirapine at delivery for the prevention of mother-to-child transmission. At delivery, various placental sites were evaluated for polymorphonuclear cell and mononuclear cell infiltration., Results: Polymorphonuclear and mononuclear cell infiltrations were common in the decidua (18% and 43%, respectively) and chorioamnion (28% and 34%, respectively). Gestational age and birthweight were lower among women with polymorphonuclear cell infiltrations, with these relationships generally stronger at earlier gestational age and birthweight. Mononuclear infiltrations were not associated with adverse outcomes. Neither polymorphonuclear cell nor mononuclear placental infiltrations were associated with mother-to-child transmission of HIV. Antibiotic use was not associated with reduced polymorphonuclear or mononuclear cell infiltrations., Conclusion: Polymorphonuclear cell infiltrations were associated with preterm birth and decreased birthweight and gestational age. Antibiotic use was not associated with reductions in polymorphonuclear or mononuclear cell infiltrations. In this nevirapine-treated population, neither polymorphonuclear nor mononuclear cell infiltration was associated with the mother-to-child transmission of HIV.

Objective: A multisite study was conducted in Africa to assess the efficacy of antibiotics to reduce mother-to-child transmission (MTCT) of HIV-1., Design: A randomized, double-blinded, placebo-controlled, phase III clinical trial., Methods: HIV-1-infected women were randomly assigned at 20-24 weeks' gestation to receive either antibiotics (metronidazole plus erythromycin antenatally and metronidazole plus ampicillin intrapartum) or placebo. Maternal study procedures were performed at 20-24, 26-30, and 36 weeks antenatally, and at labor/delivery. Infants were seen at birth, 4-6 weeks, and 3, 6, 9 and 12 months. The primary efficacy endpoints were overall infant HIV-1 infection and HIV-1-free survival at 4-6 weeks. All women and infants received single-dose nevirapine prophylaxis in this study., Results: A total of 1510 live-born infants were included in the primary analysis. The proportions of HIV-1-infected infants at birth were similar (antibiotics 7.1%; placebo 8.3%; P = 0.41). Likewise, there were no statistically significant differences at 4-6 weeks in the overall risk of MTCT of HIV-1 (antibiotics 16.2%; placebo 15.8%; P = 0.89) or HIV-1-free survival (79.4% in each study arm). Post-randomization, the proportion of women with bacterial vaginosis at the second antenatal visit was significantly lower in the antibiotics arm compared with the placebo arm (23.8 versus 39.7%; P < 0.001), but the frequency of histological chorioamnionitis was not different (antibiotics 36.9%; placebo 39.7%; P = 0.30). Adverse events in mothers and their infants did not differ by randomization arm., Conclusion: This simple antepartum and peripartum antibiotic regimen did not reduce the risk of MTCT of HIV-1.

Farmwomen are often an unacknowledged workforce, leading to a lack of targeted safety interventions. This study examined the involvement and work patterns of 665 women in Texas and 657 women in Louisiana who were 18 years old and older and whose family participated in farming operations. Surveys were used to gather specific data regarding tractor work patterns, tractor knowledge, sources of information about tractors, and demographic information in two southern states in which cattle and dairy were the major agricultural commodity. Among the sample of 1,322 women, 577 (43.6%) reported driving tractors at least one day a year. This subset was used to describe characteristics of tractors and tractor-related activities. Findings indicate that women learn to drive tractors in their 20s, use husbands as the primary source of their information about tractors, engage in a wide variety of farm activities including bush-hogging and plowing, and acknowledge knowing an average or less than an average amount about driving tractors. Women most often reported driving between 1 to 12 days/year (n = 321, 55.6%). When examining patterns of ROPS-equipped tractor use, women were 1.47 times more likely to drive a tractor without ROPS or enclosed when driving less than 12 days a year as opposed to 13-103 days/year or greater than 104 days/year. The results of this study support the need for health care professionals and safety specialists to design appropriate interventions that target women to become more knowledgeable regarding the injury risks associated with farm work while driving tractors.

Objective: Despite a growing emphasis worldwide on complex and potent antiretroviral drug regimens for the prevention of mother-to-child transmission of HIV-1 (MTCT), two-dose nevirapine (NVP) prophylaxis remains an important choice in many settings. We analyzed data from a multicenter clinical trial to determine whether timing of maternal or infant NVP was associated with MTCT between delivery and 6 weeks of age (intrapartum/early postnatal transmission; I/EP)., Methods: HIVNET 024 was a placebo-controlled, double-blind trial of empiric antibiotics to reduce chorioamnionitis-associated MTCT. This secondary analysis used data collected in the original randomized trial. Enrolled women were instructed to self-administer NVP at labor onset; infants were to receive a dose within 72 h of birth., Results: Data regarding 1491 mother-infant pairs were analyzed. The overall I/EP HIV-1 transmission rate was 8.1% at 6 weeks. Almost all women (93%) ingested NVP within 24 h of delivery; 90% of infants were given NVP within 48 h after delivery. Variations in mother or infant dose timing did not influence transmission rates, even when the combined pattern of both was taken into account through multivariate analysis. In the subset of women ingesting NVP or= 4 h)., Conclusion: Variations in the timing of maternal and infant NVP doses (within reasonable proximity to delivery) do not appear to affect the risk of MTCT.

Purpose: Length of hospital stay (LOS) of infants treated for neonatal abstinence syndrome (NAS) with methadone was compared to LOS of those treated with an oral morphine preparation (OMP, neonatal morphine solution, or deodorized tincture of opium)., Methods: A retrospective review of medical records of infants treated for NAS due to in utero exposure to methadone and/or illicit drugs such as heroin or morphine was performed for birthweight, neonatal abstinence scores, infant and maternal illicit drug exposure history, maternal methadone dose (if any), and details of treatment. Length of stay was the primary outcome measure., Results: Forty-six infants met the inclusion criteria. The median LOS of infants treated with methadone versus OMP was not significant (P > 0.05). Prolonged LOS was associated with larger pharmacological treatment doses required to control withdrawal symptoms, larger maternal methadone dose, and increased birthweight. After adjusting for these factors, exposure to opioids in utero, maternal nicotine use, hospital of treatment, severity of withdrawal symptoms, and foster care placement were not significantly associated with LOS in univariate or multivariate analyses., Conclusions: These results suggest that infants treated with OMP or methadone have similar LOS. Longer LOS is associated with both higher maternal methadone doses and higher opioid treatment dose requirements after birth. The potential effect of maternal methadone dose on neonatal LOS should be considered when treating expectant mothers on methadone maintenance therapy.

Background: The HIVNET 012 trial in Uganda demonstrated that single-dose nevirapine (NVP) can prevent HIV-1 mother-to-child transmission. NVP resistance (NVPR) mutations were detected in 25% of women 6 to 8 weeks after NVP, with a higher rate of NVPR in women with subtype D than A. This study examined emergence and fading of specific NVPR mutations in women with these subtypes., Methods: Plasma HIV-1 was analyzed with the ViroSeq genotyping system (Celera Diagnostics, Alameda, CA). Genotypes were obtained from paired samples collected 7 days and 6 to 8 weeks after NVP from 140 women, 83 with subtype A and 57 with subtype D., Results: The rate of NVPR was similar in women with subtype A vs. D at 7 days but was higher in subtype D than A at 6 to 8 weeks. The higher rate of NVPR in subtype D was explained by at least 2 factors: Y181C faded from detection at a greater rate in women with subtype A (odds ratio = 3.06; 95% CI, 1.04, 8.90) and K103N accumulated at a greater rate in women with subtype D (odds ratio = 1.74; 95% CI, 0.62, 4.87)., Conclusions: HIV-1 subtype influences selection and fading of HIV-1 variants with specific drug resistance mutations after antiretroviral drug exposure.

Often when jointly modeling longitudinal and survival data, we are interested in a multivariate longitudinal measure that may not fit well by linear models. To overcome this problem, we propose a joint longitudinal and survival model that has a nonparametric model for the longitudinal markers. We use cubic B-splines to specify the longitudinal model and a proportional hazards model to link the longitudinal measures to the hazard. To fit the model, we use a Markov chain Monte Carlo algorithm. We select the number of knots for the cubic B-spline model using the Conditional Predictive Ordinate (CPO) and the Deviance Information Criterion (DIC). The method and model selection approach are validated in a simulation. We apply this method to examine the link between viral load, CD4 count, and time to event in data from an AIDS clinical trial. The cubic B-spline model provides a good fit to the longitudinal data that could not be obtained with simple parametric models.

Purpose: This prospective longitudinal study was designed to evaluate whether the four-month Movement Assessment of Infants (MAI), predicted two-year cognitive and motor developmental status measured by the Mental (MDI) and Psychomotor (PDI) Scales of the Bayley Scales of Infant Development (BSID)., Methods: The subjects were 134 infants born at term who were considered at developmental risk due to biological and social risk factors. Different masked examiners assessed the infants at each age., Results: Infants' average MAI total risk scores (MAI TRS) at four months were negatively correlated with their BSID MDI scores (r = -0.23, p = 0.007) but not PDI scores at two years. Infants classified as high risk on the MAI (TRS >13) were approximately three times more likely than infants with a lower risk MAI classification (TRS < or =13) to have a high-risk MDI (< or =84) classification. Lower MAI risk status at four months was a predictor of cognitive functioning falling within normal limits for age (MDI >84) at two years, with 76% negative and 50% positive predictive values., Conclusion: The MAI appears to be valid for use with infants born at term who are at risk of developmental delay and may be a useful tool to help clinicians make decisions about intervention services.

Objective: To compare the number and type of nevirapine (NVP) resistance mutations detected in Ugandan women with subtype A vs. D HIV-1 infection after single-dose NVP prophylaxis., Design: In the HIVNET 012 trial, a higher rate of NVP resistance (NVPR) was seen in women with subtype D than A after single-dose NVP. In this study, the number and type of NVPR mutations detected 6-8 weeks after NVP were compared in women with subtypes A vs. D., Methods: Plasma samples were available for 282 (92%) of 306 women who received NVP in HIVNET 012. Samples were analyzed with the ViroSeq HIV-1 Genotyping System (Applied Biosystems, Foster City, CA). Subtyping was performed by phylogenetic analysis of pol region sequences., Results: Results were obtained for 279 women, including 147 with subtype A, 98 with subtype D, 6 with subtype C, and 28 with recombinant HIV-1. NVPR mutations were detected in 70 (25%) of 279 women. NVPR was more common in women with subtype D vs. A (35.7 vs. 19%, P = 0.0035). Complex patterns of NVPR mutations were detected in both subtypes. Among women with NVPR, 43% of women with subtype A and 46% of women with subtype D had >/=2 NVPR mutations. The mean number and pattern of NVPR mutations detected in women with subtypes A and D were similar., Conclusions: This study confirms a higher rate of NVPR in women with subtype D than A and further defines the pattern of NVPR mutations that emerge 6-8 weeks after single-dose NVP prophylaxis in these subtypes.

Complex issues arise when investigating the association between longitudinal immunologic measures and time to an event, such as time to relapse, in cancer vaccine trials. Unlike many clinical trials, we may encounter patients who are cured and no longer susceptible to the time-to-event endpoint. If there are cured patients in the population, there is a plateau in the survival function, S(t), after sufficient follow-up. If we want to determine the association between the longitudinal measure and the time-to-event in the presence of cure, existing methods for jointly modeling longitudinal and survival data would be inappropriate, since they do not account for the plateau in the survival function. The nature of the longitudinal data in cancer vaccine trials is also unique, as many patients may not exhibit an immune response to vaccination at varying time points throughout the trial. We present a new joint model for longitudinal and survival data that accounts both for the possibility that a subject is cured and for the unique nature of the longitudinal data. An example is presented from a cancer vaccine clinical trial.

This article proposes a new semiparametric Bayesian hierarchical model for the joint modeling of longitudinal and survival data. We relax the distributional assumptions for the longitudinal model using Dirichlet process priors on the parameters defining the longitudinal model. The resulting posterior distribution of the longitudinal parameters is free of parametric constraints, resulting in more robust estimates. This type of approach is becoming increasingly essential in many applications, such as HIV and cancer vaccine trials, where patients' responses are highly diverse and may not be easily modeled with known distributions. An example will be presented from a clinical trial of a cancer vaccine where the survival outcome is time to recurrence of a tumor. Immunologic measures believed to be predictive of tumor recurrence were taken repeatedly during follow-up. We will present an analysis of this data using our new semiparametric Bayesian hierarchical joint modeling methodology to determine the association of these longitudinal immunologic measures with time to tumor recurrence.