Hierarchical models for semi-competing risks data with application to quality of end-of-life care for pancreatic cancer

Readmission following discharge from an initial hospitalization is a key marker of quality of health care in the United States. For the most part, readmission has been used to study quality of care for patients with acute health conditions, such as pneumonia and heart failure, with analyses typically based on a logistic-Normal generalized linear mixed model. Applying this model to the study readmission among patients with increasingly prevalent advanced health conditions such as pancreatic cancer is problematic, however, because it ignores death as a competing risk. A more appropriate analysis is to imbed such studies within the semi-competing risks framework. To our knowledge, however, no comprehensive statistical methods have been developed for cluster-correlated semi-competing risks data. In this paper we propose a novel hierarchical modeling framework for the analysis of cluster-correlated semi-competing risks data. The framework permits parametric or non-parametric specifications for a range of model components, including baseline hazard functions and distributions for key random effects, giving analysts substantial flexibility as they consider their own analyses. Estimation and inference is performed within the Bayesian paradigm since it facilitates the straightforward characterization of (posterior) uncertainty for all model parameters including hospital-specific random effects. The proposed framework is used to study the risk of readmission among 5,298 Medicare beneficiaries diagnosed with pancreatic cancer at 112 hospitals in the six New England states between 2000-2009, specifically to investigate the role of patient-level risk factors and to characterize variation in risk across hospitals that is not explained by differences in patient case-mix

Evaluation of C-reactive protein, procalcitonin, tumor necrosis factor alpha, interleukin-6, and interleukin-8 as diagnostic parameters in sepsis-related fatalities

The aims of this study were to investigate the usefulness of serum C-reactive protein, procalcitonin, tumor necrosis factor alpha, interleukin-6, and interleukin-8 as postmortem markers of sepsis and to compare C-reactive protein and procalcitonin values in serum, vitreous humor, and cerebrospinal fluid in a series of sepsis cases and control subjects, in order to determine whether these measurements may be employed for the postmortem diagnosis of sepsis. Two study groups were formed, a sepsis group (eight subjects coming from the intensive care unit of two university hospitals, with a clinical diagnosis of sepsis in vivo) and control group (ten autopsy cases admitted to two university medicolegal centers, deceased from natural and unnatural causes, without elements to presume an underlying sepsis as the cause of death). Serum C-reactive protein and procalcitonin concentrations were significantly different between sepsis cases and control cases, whereas serum tumor necrosis factor alpha, interleukin-6, and interleukin-8 values were not significantly different between the two groups, suggesting that measurement of interleukin-6, interleukin-8, and tumor necrosis factor alpha is non-optimal for postmortem discrimination of cases with sepsis. In the sepsis group, vitreous procalcitonin was detectable in seven out of eight cases. In the control group, vitreous procalcitonin was clearly detectable only in one case, which also showed an increase of all markers in serum and for which the cause of death was myocardial infarction associated with multi-organic failure. According to the results of this study, the determination of vitreous procalcitonin may be an alternative to the serum procalcitonin for the postmortem diagnosis of sepsi

Contribution of H. pylori and Smoking Trends to US Incidence of Intestinal-Type Noncardia Gastric Adenocarcinoma: A Microsimulation Model

Background: Although gastric cancer has declined dramatically in the US, the disease remains the second leading cause of cancer mortality worldwide. A better understanding of reasons for the decline can provide important insights into effective preventive strategies. We sought to estimate the contribution of risk factor trends on past and future intestinal-type noncardia gastric adenocarcinoma (NCGA) incidence. Methods and Findings: We developed a population-based microsimulation model of intestinal-type NCGA and calibrated it to US epidemiologic data on precancerous lesions and cancer. The model explicitly incorporated the impact of Helicobacter pylori and smoking on disease natural history, for which birth cohort-specific trends were derived from the National Health and Nutrition Examination Survey (NHANES) and National Health Interview Survey (NHIS). Between 1978 and 2008, the model estimated that intestinal-type NCGA incidence declined 60% from 11.0 to 4.4 per 100,000 men, <3% discrepancy from national statistics. H. pylori and smoking trends combined accounted for 47% (range = 30%–58%) of the observed decline. With no tobacco control, incidence would have declined only 56%, suggesting that lower smoking initiation and higher cessation rates observed after the 1960s accelerated the relative decline in cancer incidence by 7% (range = 0%–21%). With continued risk factor trends, incidence is projected to decline an additional 47% between 2008 and 2040, the majority of which will be attributable to H. pylori and smoking (81%; range = 61%–100%). Limitations include assuming all other risk factors influenced gastric carcinogenesis as one factor and restricting the analysis to men. Conclusions: Trends in modifiable risk factors explain a significant proportion of the decline of intestinal-type NCGA incidence in the US, and are projected to continue. Although past tobacco control efforts have hastened the decline, full benefits will take decades to be realized, and further discouragement of smoking and reduction of H. pylori should be priorities for gastric cancer control efforts. Please see later in the article for the Editors' Summar

Effectiveness of Bevacizumab With First-Line Combination Chemotherapy for Medicare Patients With Stage IV Colorectal Cancer

Clinical trials have shown that adding bevacizumab to cytotoxic chemotherapy improves survival for patients with colorectal cancer, although its effectiveness in the Medicare population is uncertain

Feasibility and clinical impact of sharing patient-reported symptom toxicities and performance status with clinical investigators during a phase 2 cancer treatment trial

Clinicians can miss up to half of patients’ symptomatic toxicities in cancer clinical trials and routine practice. Although patient-reported outcome questionnaires have been developed to capture this information, it is unclear whether clinicians will make use of patient-reported outcomes to inform their own toxicity documentation, or to prompt symptom management activities

Disparities in cancer outcomes across age, sex, and race/ethnicity among patients with pancreatic cancer

Abstract Age, sex, and racial/ethnic disparities exist, but are understudied in pancreatic adenocarcinoma (PDAC). We used the Surveillance, Epidemiology, and End Results (SEER)–Medicare linked database to determine whether survival and treatment disparities persist after adjusting for demographic and clinical characteristics. Our study included PDAC patients diagnosed between 1992 and 2011. We used Cox regression to compare survival across age, sex, and race/ethnicity within early‐stage and late‐stage cancer subgroups, adjusting for marital status, urban location, socioeconomics, SEER region, comorbidities, stage, lymph node status, tumor location, tumor grade, diagnosis year, and treatment received. We used logistic regression to compare differences in treatment received across age, sex, and race/ethnicity. Among 20,896 patients, 84% were White, 9% Black, 5% Asian, and 2% Hispanic. Median age was 75; 56% were female and 53% had late‐stage cancer. Among early‐stage patients in the adjusted Cox model, older patient subgroups had worse survival compared with ages 66–69 (HR > 1.1, P 69); no survival differences existed between sexes. Black (HR = 1.1, P = 0.01) and Hispanic (HR = 1.2, P < 0.01) patients had worse survival compared with White. Among late‐stage cancer patients, patients over age 84 had worse survival than those aged 66–69 (HR = 1.1, P < 0.01), and males (HR = 1.08, P < 0.01) had worse survival than females; there were no racial/ethnic differences. Older age and minority race/ethnicity were associated with lower likelihood of receiving chemotherapy, radiation, and/or surgery. Age and racial/ethnic disparities in survival outcomes and treatment received exist for PDAC patients; these disparities persist after adjusting for differences in demographic and clinical characteristics

Feasibility of Patient Reporting of Symptomatic Adverse Events via the Patient-Reported Outcomes Version of the Common Terminology Criteria for Adverse Events (PROCTCAE) in a Chemoradiotherapy Cooperative Group Multicenter Clinical Trial

Purpose—To assess the feasibility of measuring symptomatic adverse events (AEs) in a multicenter clinical trial using the National Cancer Institute’s Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE). Methods and Materials—Patients enrolled in Trial XXXX (XXXX) were asked to self-report 53 PRO-CTCAE items representing 30 symptomatic AEs at 6 time points (baseline; weekly x4 during treatment; 12-weeks post-treatment). Reporting was conducted via wireless tablet computers in clinic waiting areas. Compliance was defined as the proportion of visits when an expected PRO-CTCAE assessment was completed. Results—Among 226 study sites participating in Trial XXXX, 100% completed 35-minute PROCTCAE training for clinical research associates (CRAs); 80 sites enrolled patients of which 34 (43%) required tablet computers to be provided. All 152 patients in Trial XXXX agreed to selfreport using the PRO-CTCAE (median age 66; 47% female; 84% white). Median time for CRAs to learn the system was 60 minutes (range 30–240), and median time for CRAs to teach a patient to self-report was 10 minutes (range 2–60). Compliance was high, particularly during active treatment when patients self-reported at 86% of expected time points, although compliance was lower post-treatment (72%). Common reasons for non-compliance were institutional errors such as forgetting to provide computers to participants; patients missing clinic visits; internet connectivity; and patients feeling “too sick”. Conclusions—Most patients enrolled in a multicenter chemoradiotherapy trial were willing and able to self-report symptomatic adverse events at visits using tablet computers. Minimal effort was required by local site staff to support this system. The observed causes of missing data may be obviated by allowing patients to self-report electronically between-visits, and by employing central compliance monitoring. These approaches are being incorporated into ongoing studies

Phase I Study of Cetuximab, Irinotecan, and Vandetanib (ZD6474) as Therapy for Patients with Previously Treated Metastastic Colorectal Cancer

BACKGROUND: To determine the maximum tolerated dose (MTD) and safety, and explore efficacy and biomarkers of vandetanib with cetuximab and irinotecan in second-line metastatic colorectal cancer. METHODS: Vandetanib (an orally bioavailable VEGFR-2 and EGFR tyrosine kinases inhibitor) was combined at 100 mg, 200 mg, or 300 mg daily with standard dosed cetuximab and irinotecan (3+3 dose-escalation design). Ten patients were treated at the MTD and plasma angiogenesis biomarkers (VEGF, PlGF, bFGF, sVEGFR1, sVEGFR2, IL-1β, IL-6, IL-8, TNF-α, SDF1α) were measured before and after treatment. RESULTS: Twenty-seven patients were enrolled at 4 dose levels and the MTD. Two dose-limiting toxicities (grade 3 QTc prolongation and diarrhea) were detected at 300 mg of vandetanib with cetuximab and irinotecan resulting in 200 mg being the MTD. Seven percent of patients had a partial response, 59% stable disease and 34% progressed. Median progression-free survival was 3.6 months (95% CI, 3.2-5.6) and median overall survival was 10.5 months (95% CI, 5.1-20.7). Toxicities were fairly manageable with grade 3 or 4 diarrhea being most prominent (30%). Vandetanib and cetuximab treatment induced a sustained increase in plasma PlGF and a transient decrease in plasma sVEGFR1, but no changes in plasma VEGF and sVEGFR2. CONCLUSIONS: Vandetanib can be safely combined with cetuximab and irinotecan for metastatic colorectal cancer. Exploratory biomarker analyses suggest differential effects on certain plasma biomarkers for VEGFR inhibition when combined with EGFR blockade and a potential correlation between baseline sVEGFR1 and response. However, while the primary endpoint was safety, the observed efficacy raises concern for moving forward with this combination. TRIAL REGISTRATION: Clinicaltrials.gov NCT00436072

Evaluation of different recall periods for the US National Cancer Institute’s Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE)

Aims—The U.S. National Cancer Institute recently developed the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE). PRO-CTCAE is a library of questions for clinical trial participants to self-report symptomatic adverse events (e.g., nausea). The objective of this study is to inform evidence-based selection of a recall period when PRO-CTCAE is included in a trial. We evaluated differences between 1-week, 2-week, 3-week, and 4-week recall periods, using daily reporting as the reference. Methods—English-speaking patients with cancer receiving chemotherapy and/or radiotherapy were enrolled at four U.S. cancer centers and affiliated community clinics. Participants completed 27 PRO-CTCAE items electronically daily for 28 days, and then weekly over 4 weeks, using 1-week, 2-week, 3-week, and 4-week recall periods. For each recall period, mean differences, effect sizes, and intraclass correlation coefficients were calculated to evaluate agreement between the maximum of daily ratings and the corresponding ratings obtained using longer recall periods (e.g., maximum of daily scores over 7 days vs. 1-week recall). Analyses were repeated using the average of daily scores within each recall period rather than the maximum of daily scores. Results—127 subjects completed questionnaires (57% male; median age 57). The median of the 27 mean differences in scores on the PRO-CTCAE 5-point response scale comparing the maximum daily versus the longer recall period (and corresponding effect size), was −0.20 (−0.20) for 1-week recall; −0.36 (−0.31) for 2-week recall; −0.45 (−0.39) for 3-week recall; and −0.47 (−0.40) for 4-week recall. The median intraclass correlation across 27 items between the maximum of daily ratings and the corresponding longer recall ratings for 1-week recall was 0.70 (range: 0.54–0.82); 2-week recall: 0.74 (range: 0.58–0.83); 3-week recall: 0.72 (range: 0.61–0.84); and 4-week recall: 0.72 (range: 0.64–0.86). Similar results were observed for all analyses using the average of daily scores rather than the maximum of daily scores. Conclusions—1-week recall corresponds best to daily reporting. Although intraclass correlations remain stable over time, there are small but progressively larger differences between daily and longer recall periods at 2, 3, and 4 weeks, respectively. The preferred recall period for the PRO-CTCAE is the past 7 days, although investigators may opt for recall periods of 2, 3, or 4 weeks with an understanding that there may be some information loss

Symptom Monitoring With Patient-Reported Outcomes During Routine Cancer Treatment: A Randomized Controlled Trial

There is growing interest to enhance symptom monitoring during routine cancer care using patient-reported outcomes, but evidence of impact on clinical outcomes is limited