Program Director Attitudes Toward Acceptance of Pediatric Dentistry Entrustable Professional Activities (EPAs).

Purpose: To acquire comments on pediatric dentistry entrustable professional activities (EPAs) from pediatric dentistry residency program directors (PDs). Methods: An electronic survey invited PDs to evaluate 16 previously developed EPAs on whether they were critical to patient safety, resident education, or both. PDs were asked to evaluate a fully developed EPA to assess structure and clarity and describe barriers to EPA. Descriptive statistics were completed. Results: Forty-one of 103 PDs completed the entire survey. Eighty-five percent (36 of 42) of PDs believed EPAs are critical to pediatric dentistry education, and 81 percent (34 of 42) believed EPAs are critical to patient safety. Eighty-one percent of PDs would likely use EPAs when available. Seventy-five percent (31 of 41) of PDs reported that they have had a resident who would have benefited from a longer duration of training. Conclusions: The majority of pediatric dentistry residency program director participants surveyed reported that entrustable professional activities are critical to patient safety and resident education. EPAs may be a valuable option for assessing residents' readiness for graduation.

Prenatal Opioid Exposure and Risk for Adverse Brain and Motor Outcomes in Infants Born Premature.

OBJECTIVE: To compare brain magnetic resonance imaging (MRI) biomarkers and neurodevelopmental test scores in infants born preterm with and without prenatal opioid exposure (POE). STUDY DESIGN: We examined 395 preterm infants (≤32 weeks gestational age) who had term-equivalent brain MRIs, composite scores from the Bayley Scales of Infant and Toddler Development-III at 2 years corrected age, and POE data. MRI parameters included total/regional brain volumes and severe punctate white matter lesions (PWMLs). We conducted bivariable analysis and multivariable logistic regression analyses. RESULTS: The mean ± SD gestational age was 29.3 ± 2.5 weeks; 35 (8.9%) had POE and 20 (5.1%) had severe PWML. Compared with unexposed infants, those with POE exhibited higher rates of severe PWML (17.1% vs 3.9%, respectively; P = .002); findings remained significant with an OR of 4.16 (95% CI, 1.26-13.68) after adjusting for confounders. On mediation analysis, the significant relationship between POE and severe PWML was not indirectly mediated through preterm birth/gestational age (OR, 0.93; 95% CI, 0.78-1.10), thus suggesting the association was largely driven by a direct adverse effect of POE on white matter. In multivariable analyses, POE was associated with a significantly lower score by -6.2 (95% CI, -11.8 to -0.6) points on the Bayley Scales of Infant and Toddler Development-III Motor subscale compared with unexposed infants. CONCLUSIONS: POE was associated with severe PWML; this outcome may be a direct effect of POE rather than being mediated by premature birth. POE was also associated with worse motor development. Continued follow-up to understand the long-term effects of POE is warranted.

Safety and efficacy of sirolimus in hospitalised patients with COVID-19 pneumonia.

BACKGROUND: There is a critical need to develop novel therapies for COVID-19. METHODS: We conducted a phase 2, multicentre, placebo-controlled, double-blind, randomised trial; hospitalised patients with hypoxemic respiratory failure due to COVID-19 and at least one poor prognostic biomarker, were given sirolimus (6 mg on Day 1 followed by 2 mg daily for 14 days or hospital discharge, whichever happens first) or placebo, in a 2:1 randomization scheme favouring sirolimus. Primary outcome was the proportion of patients alive and free from advanced respiratory support measures at Day 28. RESULTS: Between April 2020 and April 2021, 32 patients underwent randomization and 28 received either sirolimus (n = 18) or placebo (n = 10). Mean age was 57 years and 75 % of the subjects were men. Twenty-two subjects had at least one co-existing condition (Diabetes, hypertension, obesity, CHF, or asthma/COPD) associated with worse prognosis. Mean FiO2 requirement was 0.35. There was no difference in the proportion of patients who were alive and free from advanced respiratory support measures in the sirolimus group (n = 15, 83 %) compared with the placebo group (n = 8, 80 %). Although patients in the sirolimus group demonstrated faster improvement in oxygenation and spent less time in the hospital, these differences were not statistically significant. There was no between-group difference in the rate of change in serum biomarkers such as LDH, ferritin, d-dimer or lymphocyte count. There was a decreased risk of thromboembolic complications in patients on sirolimus compared with placebo. CONCLUSIONS: Larger studies are warranted to evaluate the role sirolimus in COVID-19 infection.

Prenatal tobacco smoke exposure and risk for cognitive delays in infants born very premature.

Prenatal tobacco smoke exposure (TSE) and prematurity are independent risk factors for abnormal neurodevelopment. The objectives were to compare differences in Bayley-III cognitive, language, and motor scores at 2 years corrected age (CA) in 395 infants born very preterm (≤ 32 weeks gestation) with and without prenatal TSE. We performed multivariable linear regression analyses to examine associations between prenatal TSE and neurodevelopmental outcomes and a mediation analysis to estimate direct effects of prenatal TSE on outcomes and indirect effects through preterm birth. In total, 50 (12.6%) infants had prenatal TSE. Infants with prenatal TSE had lower mean [95% CI] Cognitive score (82.8 [78.6, 87.1]) vs. nonexposed infants (91.7 [90.1, 93.4]). In children with and without prenatal TSE, there were significant differences in mean [95% CI] Language scores (81.7 [76.0, 87.4] vs. 92.4 [90.2, 94.6], respectively) and mean [95% CI] Motor scores (86.5 [82.2, 90.7] vs. 93.4 [91.8, 95.0], respectively); scores remained significant after controlling for confounders. Preterm birth indirectly mediated 9.0% of the total effect of prenatal TSE on Cognitive score (P = NS). However, 91% of the remaining total effect was significant and attributable to TSE's direct harmful effects on cognitive development (ß = - 5.17 [95% CI - 9.97, - 0.38]). The significant association is largely due to TSE's direct effect on cognitive development and not primarily due to TSE's indirect effect on preterm birth.

Structured Callouts, the Shared Mental Model, and Teamwork: A Video-Based Study in a Pediatric Emergency Department.

OBJECTIVES: The shared mental model is essential to high-quality resuscitations. A structured callout (SCO) is often performed to establish the shared mental model, but the literature on SCOs is limited. The objectives of this study are to describe performance of SCOs during pediatric medical emergencies and to determine whether a SCO is associated with better teamwork. METHODS: This was a retrospective study in the resuscitation area of an academic pediatric emergency department, where performance of a SCO is a standard expectation. Only medical or nontrauma patients were eligible for inclusion. Data collection was performed by structured video review by 2 observers and verified by a third blinded observer. A SCO was defined as team leader (Pediatric Emergency Medicine fellow or faculty physician) verbalization of at least 1 element of the patient history/examination or an assessment of patient physiology and 1 element of the diagnostic or therapeutic plan. We independently measured teamwork using the Teamwork Emergency Assessment Measure (TEAM) tool. RESULTS: We reviewed 60 patient encounters from the pediatric emergency department resuscitation area between April 2018 and June 2020. Median patient age was 6 years; the team leader was a Pediatric Emergency Medicine fellow in 55% of encounters. The physician team leader performed a SCO in 38 (63%) of patient encounters. The TEAM scores were collected for 46 encounters. Mean TEAM score (SD) was 42.3 (1.7) in patients with a SCO compared with 40.0 (3.0) in those without a SCO ( P = 0.007). CONCLUSIONS: Performance of a SCO was associated with better teamwork, but the difference was of unclear clinical significance.

GABA(A) receptor activation drives GABARAP-Nix mediated autophagy to radiation-sensitize primary and brain-metastatic lung adenocarcinoma tumors.

In non-small cell lung cancer (NSCLC) treatment, targeted therapies benefit only a subset of NSCLC, while radiotherapy responses are not durable and toxicity limits therapy. We find that a GABA(A) receptor activator, AM-101, impairs viability and clonogenicity of NSCLC primary and brain metastatic cells. Employing an ex vivo 'chip', AM-101 is as efficacious as the chemotherapeutic docetaxel, which is used with radiotherapy for advanced-stage NSCLC. In vivo , AM-101 potentiates radiation, including conferring a survival benefit to mice bearing NSCLC intracranial tumors. GABA(A) receptor activation stimulates a selective-autophagic response via multimerization of GABA(A) Receptor-Associated Protein (GABARAP), stabilization of mitochondrial receptor Nix, and utilization of ubiquitin-binding protein p62. A targeted-peptide disrupting Nix binding to GABARAP inhibits AM-101 cytotoxicity. This supports a model of GABA(A) receptor activation driving a GABARAP-Nix multimerization axis triggering autophagy. In patients receiving radiotherapy, GABA(A) receptor activation may improve tumor control while allowing radiation dose de-intensification to reduce toxicity. Highlights: Activating GABA(A) receptors intrinsic to lung primary and metastatic brain cancer cells triggers a cytotoxic response. GABA(A) receptor activation works as well as chemotherapeutic docetaxel in impairing lung cancer viability ex vivo . GABA(A) receptor activation increases survival of mice bearing lung metastatic brain tumors.A selective-autophagic response is stimulated by GABA(A) receptor activation that includes multimerization of GABARAP and Nix.Employing a new nanomolar affinity peptide that abrogates autophagosome formation inhibits cytotoxicity elicited by GABA(A) receptor activation.

The Association of Emergency Severity Index Score and Patient and Family Experience in a Pediatric Emergency Department.

The study aim was to determine the relationship between a patient's Emergency Severity Index (ESI) score and their or their family's response to the key performance indicator (KPI) question on the post-visit patient and family experience (PFE) survey. Retrospective review of patients presenting to the Pediatric Emergency Department between July 1, 2021, and June 30, 2022, who completed the KPI question on an associated post-visit survey. We performed univariate analyses on all candidate variables; multivariable linear regression identified independent predictors of KPI on the PFE survey. A total of 8136 patients were included in the study. Although ESI score was significantly associated with PFE in univariate analysis, this association was lost in the multivariable model. Independent associations were appreciated with race/ethnicity, time to provider, length of stay, and procedure performance during the visit. Although ESI is not independently associated with PFE in this study, its interaction with factors such as time to provider, length of stay, and procedure performance may be important for emergency department providers creating interventions to impact experience during low acuity visits.

A Video-Based Study of Emergency Medical Services Handoffs to a Pediatric Emergency Department.

BACKGROUND: Emergency medical services (EMS) to emergency department (ED) handoffs are important moments in patient care, but patient information is communicated inconsistently. OBJECTIVE: The aim of this study was to describe the duration, completeness, and communication patterns of patient handoffs from EMS to pediatric ED clinicians. METHODS: We conducted a video-based, prospective study in the resuscitation suite of an academic pediatric ED. All patients 25 years and younger transported via ground EMS from the scene were eligible. We completed a structured video review to assess frequency of transmission of handoff elements, handoff duration, and communication patterns. We compared outcomes between medical and trauma activations. RESULTS: We included 156 of 164 eligible patient encounters from January to June 2022. Mean (SD) handoff duration was 76 (39) seconds. Chief symptom and mechanism of injury were included in 96% of handoffs. Most EMS clinicians communicated prehospital interventions (73%) and physical examination findings (85%). However, vital signs were reported for fewer than one-third of patients. EMS clinicians were more likely to communicate prehospital interventions and vital signs for medical compared with trauma activations (p < 0.05). Communication challenges between EMS clinicians and the ED were common; ED clinicians interrupted EMS or requested information already communicated by EMS in nearly one-half of handoffs. CONCLUSIONS: EMS to pediatric ED handoffs take longer than recommended and frequently lack important patient information. ED clinicians engage in communication patterns that may hinder organized, efficient, and complete handoff. This study highlights the need for standardizing EMS handoff and ED clinician education regarding communication strategies to ensure active listening during EMS handoff.

Risk of Bacteremia in Febrile Children and Young Adults With Sickle Cell Disease in a Multicenter Emergency Department Cohort.

Importance: Bacteremia is a major cause of morbidity and mortality in children and young adults with sickle cell disease (SCD), but among those presenting to the emergency department (ED) with fever, the absolute risk of, risk factors associated with, and outcomes of bacteremia are poorly defined. Objective: To obtain contemporary data on the absolute risk of, risk factors associated with, and outcomes associated with bacteremia in children and young adults with SCD presenting to the ED with fever. Design, Setting, and Participants: A multicenter retrospective cohort study was conducted of individuals with SCD younger than 22 years (young adults) presenting to EDs within the Pediatric Health Information Systems database from January 1, 2016, to December 31, 2021, with fever (identified by diagnostic codes for fever or the collection of blood samples for cultures and intravenous antibiotic administration). Data analysis was performed from May 17 to December 15, 2022. Main Outcomes and Measures: The risk of bacteremia (defined by diagnostic coding) was identified in these children and young adults, and univariate analyses and multivariable regression were used to examine patient-level factors and bacteremia. Results: A total of 35 548 encounters representing 11 181 individual patients from 36 hospitals were evaluated. The median age of the cohort was 6.17 (IQR, 2.36-12.11) years and 52.9% were male. Bacteremia was present in 405 encounters (1.1%, 95% CI, 1.05%-1.26%). A history of bacteremia, osteomyelitis, stroke, central line-associated bloodstream infection (CLABSI), central venous catheter, or apheresis was associated with the diagnosis of bacteremia, while age, sex, hemoglobin SC genotype, and race and ethnicity were not. In the multivariable analysis, individuals with a history of bacteremia (odds ratio [OR], 1.36; 95% CI, 1.01-1.83), CLABSI (OR, 6.39; 95% CI, 3.02-13.52), and apheresis (OR, 1.77; 95% CI, 1.22-2.55) had higher odds of bacteremia. Conclusions and Relevance: The findings of this large cohort study suggest that bacteremia in children and young adults with SCD presenting with fever is rare. A history of invasive bacterial infection, CLABSI, or a central line appears to be associated with bacteremia, while age and SCD genotype are not.

Dynamic use of historical controls in clinical trials for rare disease research: A re-evaluation of the MILES trial.

BACKGROUND: Randomized controlled trials offer the best design for eliminating bias in estimating treatment effects but can be slow and costly in rare disease research. Additionally, an equal randomization approach may not be optimal in studies in which prior evidence of superiority of one or more treatments exist. Supplementing prospectively enrolled, concurrent controls with historical controls can reduce recruitment requirements and provide patients a higher likelihood of enrolling in a new and possibly superior treatment arm. Appropriate methods need to be employed to ensure comparability of concurrent and historical controls to minimize bias and variability in the treatment effect estimates and reduce the chances of drawing incorrect conclusions regarding treatment benefit. METHODS: MILES was a phase III placebo-controlled trial employing 1:1 randomization that led to US Food and Drug Administration approval of sirolimus for treating patients with lymphangioleiomyomatosis. We re-analyzed the MILES trial data to learn whether substituting concurrent controls with controls from a historical registry could have accelerated subject enrollment while leading to similar study conclusions. We used propensity score matching to identify exchangeable historical controls from a registry balancing the baseline characteristics of the two control groups. This allowed more new patients to be assigned to the sirolimus arm. We used trial data and simulations to estimate key outcomes under an array of alternative designs. RESULTS: Borrowing information from historical controls would have allowed the trial to enroll fewer concurrent controls while leading to the same conclusion reached in the trial. Simulations showed similar statistical performance for borrowing as for the actual trial design without producing type I error inflation and preserving power for the same study size when concurrent and historical controls are comparable. CONCLUSION: Substituting concurrent controls with propensity score-matched historical controls can allow more prospectively enrolled patients to be assigned to the active treatment and enable the trial to be conducted with smaller overall sample size, while maintaining covariate balance and study power and minimizing bias in response estimation. This approach does not fully eliminate the concern that introducing non-randomized historical controls in a trial may lead to bias in estimating treatment effects, and should be carefully considered on a case-by-case basis. Borrowing historical controls is best suited when conducting randomized controlled trials with conventional designs is challenging, as in rare disease research. High-quality data on covariates and outcomes must be available for candidate historical controls to ensure the validity of these designs. Additional precautions are needed to maintain blinding of the treatment assignment and to ensure comparability in the assessment of treatment safety.MILES ClinicalTrials.gov Number: NCT00414648.

Durvalumab plus Cetuximab in Patients with Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma: An Open-label, Nonrandomized, Phase II Clinical Trial.

PURPOSE: The efficacy of cetuximab is poor in metastatic head and neck squamous cell carcinoma (HNSCC). Cetuximab initiates natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity, with resultant recruitment of immune cells and suppression of antitumor immunity. We hypothesized that adding an immune-checkpoint inhibitor (ICI) could overcome this and lead to an enhanced antitumor response. PATIENTS AND METHODS: A phase II study of cetuximab and durvalumab in metastatic HNSCC was conducted. Eligible patients had measurable disease. Patients who had received both cetuximab and an ICI were excluded. The primary endpoint was objective response rate (ORR) by RECIST 1.1 at 6 months. RESULTS: As of April 2022, 35 patients enrolled, of whom 33 received at least 1 dose of durvalumab and were included in the response analysis. Eleven patients (33%) had received prior platinum-based chemotherapy, 10 an ICI (30%), and 1 patient (3%) cetuximab. ORR was 39% (13/33) with a median duration of response of 8.6 months [95% confidence interval (CI): 6.5-16.8]. Median progression-free and overall survivals were 5.8 months (95% CI: 3.7-14.1) and 9.6 months (95% CI: 4.8-16.3), respectively. There were 16 grade 3 treatment-related adverse events (TRAE) and one grade 4 TRAE, with no treatment-related deaths. Overall and progression-free survival did not correlate with PD-L1 status. NK cell cytotoxic activity was increased by cetuximab and further increased with the addition of durvalumab in responders. CONCLUSIONS: The combination of cetuximab and durvalumab demonstrated durable activity with a tolerable safety profile in metastatic HNSCC and warrants further investigation.

Prenatal tobacco smoke exposure and risk of brain abnormalities on magnetic resonance imaging at term in infants born very preterm.

BACKGROUND: Prenatal tobacco smoke exposure and preterm birth are associated with abnormal brain and neurodevelopmental outcomes in infants. Studies that can disentangle indirect mediating effects from direct effects of prenatal tobacco smoke exposure on sensitive early brain magnetic resonance imaging biomarkers in very preterm infants are needed. OBJECTIVE: This study aimed to determine whether prenatal tobacco smoke exposure in preterm infants posed any direct effects on magnetic resonance imaging-determined global brain abnormality score and secondary measures of brain abnormalities after removing any indirect mediating effects of preterm birth on neurostructural outcomes. STUDY DESIGN: We examined brain magnetic resonance imaging findings collected at 39 to 44 weeks postmenstrual age from a prospective cohort of 395 infants born very preterm (gestational age of ≤32 weeks). The primary outcome was global brain abnormality score, and the secondary outcomes were global efficiency of structural connectome, diffuse white matter abnormality volume, total brain tissue volume, total gray and white matter volumes, and cerebellar volume. Maternal reports of smoking during pregnancy were obtained. We performed multivariable linear regression analyses to examine the association between prenatal tobacco smoke exposure and our magnetic resonance imaging outcomes, controlling for prospectively collected confounders. Moreover, we performed a mediation analysis to estimate the direct effects of prenatal tobacco smoke exposure on brain abnormalities and any indirect effects through preterm birth. RESULTS: Overall, 12.6% of infants had prenatal tobacco smoke exposure. Infants with prenatal tobacco smoke exposure had a higher median global brain abnormality score than nonexposed infants (7 [interquartile range, 0-41] vs 5 [interquartile range, 0-34]; P≤.001); the findings remained significant (P<.001) after controlling for antenatal confounders. Global efficiency (P<.001), diffuse white matter volume (P=.037), and total brain tissue volume (P=.047) were significantly different between TSE groups in multivariable analyses. On mediation analysis, preterm birth mediated between 0% and 29% of the indirect effect of prenatal tobacco smoke exposure on several measures of brain abnormality outcomes. Thus, prenatal tobacco smoke exposure had a direct adverse effect between 71% and 100% on brain injury or abnormal development. CONCLUSION: Our study has identified multiple adverse effects of prenatal tobacco smoke exposure on sensitive and objective measures of neonatal brain injury and abnormal development; most cases seemed to be a direct effect of prenatal tobacco smoke exposure on fetal brain development. The results underscored the significant adverse neurostructural effects of prenatal tobacco smoke exposure to tobacco smoke pollutants.

Phase II Trial of Adjuvant Nivolumab Following Salvage Resection in Patients with Recurrent Squamous Cell Carcinoma of the Head and Neck.

PURPOSE: Locoregional relapse in patients with head and neck squamous cell carcinoma (HNSCC) is common, approaching 50% for some subsites despite multimodality therapy. Salvage surgery is the standard of care, but able to achieve durable control in only a minority of patients. While adjuvant radiotherapy or chemo-radiotherapy is offered to select patients, this approach can be prohibitively toxic. Given the activity and tolerability of programmed death-1 inhibitors in metastatic HNSCC, we investigated the safety and efficacy of adjuvant nivolumab after salvage surgical resection. PATIENTS AND METHODS: This was an open-label, multi-institutional phase II clinical trial (NCT03355560). Patients with recurrent, resectable HNSCC were enrolled within 6 weeks of salvage surgery. Six 28-day cycles of adjuvant nivolumab were planned. The primary endpoint was 2-year disease-free survival (DFS) more than 58%, based on an institutional historical control group of 71 patients with recurrent HNSCC who underwent salvage surgery. RESULTS: Between February 2018 and February 2020, 39 patients were enrolled. At a median follow-up of 22.1 months, 2-year DFS was 71.4% [95% confidence interval (CI), 57.8-88.1] and the 2-year overall survival (OS) was 73% (95% CI, 58-91.8). Three of 39 (8%) patients experienced grade 3 treatment-related adverse events and 3 of 39 (8%) discontinued treatment due to side effects. Ten of 39 had locoregional recurrence, while 2 of 10 also had synchronous metastatic disease. There was no difference in DFS between PD ligand-1 (PD-L1)-positive and PD-L1-negative patients. There was a nonsignificant trend toward improved DFS in patients with high tumor mutational burden (P = 0.083). CONCLUSIONS: Adjuvant nivolumab after salvage surgery in locally recurrent HNSCC is well tolerated and showed improved DFS compared with historical controls.

Phase II Clinical Trial of Neoadjuvant and Adjuvant Pembrolizumab in Resectable Local-Regionally Advanced Head and Neck Squamous Cell Carcinoma.

PURPOSE: Patients with resected, local-regionally advanced, head and neck squamous cell carcinoma (HNSCC) have a one-year disease-free survival (DFS) rate of 65%-69% despite adjuvant (chemo)radiotherapy. Neoadjuvant PD-1 immune-checkpoint blockade (ICB) has demonstrated clinical activity, but biomarkers of response and effect on survival remain unclear. PATIENTS AND METHODS: Eligible patients had resectable squamous cell carcinoma of the oral cavity, larynx, hypopharynx, or oropharynx (p16-negative) and clinical stage T3-T4 and/or two or more nodal metastases or clinical extracapsular nodal extension (ENE). Patients received neoadjuvant pembrolizumab 200 mg 1-3 weeks prior to surgery, were stratified by absence (intermediate-risk) or presence (high-risk) of positive margins and/or ENE, and received adjuvant radiotherapy (60-66 Gy) and concurrent pembrolizumab (every 3 weeks × 6 doses). Patients with high-risk HNSCC also received weekly, concurrent cisplatin (40 mg/m2). Primary outcome was one-year DFS. Secondary endpoints were one-year overall survival (OS) and pathologic response (PR). Safety was evaluated with CTCAE v5.0. RESULTS: From February 2016 to October 2020, 92 patients enrolled. The median age was 59 years (range, 27-80), 30% were female, 86% had stage T3-T4, and 69% had ≥N2. At a median follow-up of 28 months, one-year DFS was 97% (95% CI, 71%-90%) in the intermediate-risk group and 66% (95% CI, 55%-84%) in the high-risk group. Patients with a PR had significantly improved one-year DFS relative to patients without response (93% vs. 72%, hazard ratio 0.29; 95% CI, 11%-77%). No new safety signals were identified. CONCLUSIONS: Neoadjuvant and adjuvant pembrolizumab increased one-year DFS rate in intermediate-risk, but not high-risk, HNSCC relative to historical control. PR to neoadjuvant ICB is a promising surrogate for DFS.

A Bayesian semiparametric method for analyzing length-biased data.

Survival data obtained from prevalent cohort study designs are often subject to length-biased sampling. Frequentist methods including estimating equation approaches, as well as full likelihood methods, are available for assessing covariate effects on survival from such data. Bayesian methods allow a perspective of probability interpretation for the parameters of interest, and may easily provide the predictive distribution for future observations while incorporating weak prior knowledge on the baseline hazard function. There is lack of Bayesian methods for analyzing length-biased data. In this paper, we propose Bayesian methods for analyzing length-biased data under a proportional hazards model. The prior distribution for the cumulative hazard function is specified semiparametrically using I-Splines. Bayesian conditional and full likelihood approaches are developed for analyzing simulated and real data.

Critical appraisal of Bayesian dynamic borrowing from an imperfectly commensurate historical control.

Bayesian dynamic borrowing designs facilitate borrowing information from historical studies. Historical data, when perfectly commensurate with current data, have been shown to reduce the trial duration and the sample size, while inflation in the type I error and reduction in the power have been reported, when imperfectly commensurate. These results, however, were obtained without considering that Bayesian designs are calibrated to meet regulatory requirements in practice and even no-borrowing designs may use information from historical data in the calibration. The implicit borrowing of historical data suggests that imperfectly commensurate historical data may similarly impact no-borrowing designs negatively. We will provide a fair appraiser of Bayesian dynamic borrowing and no-borrowing designs. We used a published selective adaptive randomization design and real clinical trial setting and conducted simulation studies under varying degrees of imperfectly commensurate historical control scenarios. The type I error was inflated under the null scenario of no intervention effect, while larger inflation was noted with borrowing. The larger inflation in type I error under the null setting can be offset by the greater probability to stop early correctly under the alternative. Response rates were estimated more precisely and the average sample size was smaller with borrowing. The expected increase in bias with borrowing was noted, but was negligible. Using Bayesian dynamic borrowing designs may improve trial efficiency by stopping trials early correctly and reducing trial length at the small cost of inflated type I error.

Residual tumor volume discriminates prognosis after surgery for neuroendocrine liver metastasis.

BACKGROUND AND OBJECTIVES: We developed objective measurements of preoperative and residual tumor volume, and debulking rate, to evaluate their prognostic value for neuroendocrine liver metastasis (NELM). METHODS: Seventy-three patients who underwent surgery for NELM were analyzed retrospectively. Indices of preoperative and postoperative residual tumor volume (pre-volume index [VI] and post-VI) were calculated as the sum of the cubes of individual tumor diameters on preoperative and postoperative imaging, respectively. The debulking rate (%) was calculated as 100 - 100 × post-VI/pre-VI. The classification and regression trees method was used to classify pre-VI and post-VI. RESULTS: Overall survival (OS) was discriminated by preoperative tumor volume (5-year OS rates, 87.8% for low pre-VI and 60.1% for high pre-VI; P = .037) and residual tumor volume (5-year OS rates, 88.1% for low post-VI and 24.8% for high post-VI; P < .001). In contrast, debulking rates of 100%, ≥90%, and <90% did not discriminate OS (5-year OS rates, 88.0%, 61.9%, and 58.9%, respectively, not significant). In multivariate analysis, residual tumor volume (high post-VI, hazard ratio, 6.40; 95% confidence interval, 1.45-32.3) was an independent prognostic factor for OS. CONCLUSIONS: Objective measurement of tumor volume demonstrates that residual tumor volume is prognostic after surgery for NELM.

PI3-kinase pathway biomarkers in oral cancer and tumor immune cells.

BACKGROUND: This study investigated the hypothesis that phosphoinositide 3-kinase (PI3-kinase) pathway dysregulation in either head and neck cancer cells and/or tumor infiltrating immune cells would influence outcomes of patients with surgically treated oral tongue squamous cell carcinomas (SCC). METHODS: We constructed tissue microarrays containing 123 oral tongue SCC samples and performed immunohistochemistry using antibodies against 7 PI3-kinase pathway markers: phosphatase and tensin homolog (PTEN), Akt, p-Akt, mammalian target of rapamycin (mTOR), phosphorylated-mammalian target of rapamycin (p-mTOR), survivin, and Ki-67). Expression levels in cancer cells or tumor infiltrating immune cells were correlated with outcomes. RESULTS: Higher levels of PTEN expression in immune cells were significantly associated with improved recurrence-free survival (heart rate (HR) = 0.45, 95% confidence interval (CI) 0.23-0.90, P = .03), and overall survival (HR = 0.34, 95% CI 0.15-0.76, P = .01) on univariate and multicovariate models. CONCLUSIONS: We identified a novel, negative prognostic role of PI3-kinase activation (as determined by PTEN loss) in oral SCC infiltrating immune cells. These findings could be relevant for clinical development of PI-3 kinase inhibitors for this disease.

Bayesian selective response-adaptive design using the historical control.

High quality historical control data, if incorporated, may reduce sample size, trial cost, and duration. A too optimistic use of the data, however, may result in bias under prior-data conflict. Motivated by well-publicized two-arm comparative trials in stroke, we propose a Bayesian design that both adaptively incorporates historical control data and selectively adapt the treatment allocation ratios within an ongoing trial responsively to the relative treatment effects. The proposed design differs from existing designs that borrow from historical controls. As opposed to reducing the number of subjects assigned to the control arm blindly, this design does so adaptively to the relative treatment effects only if evaluation of cumulated current trial data combined with the historical control suggests the superiority of the intervention arm. We used the effective historical sample size approach to quantify borrowed information on the control arm and modified the treatment allocation rules of the doubly adaptive biased coin design to incorporate the quantity. The modified allocation rules were then implemented under the Bayesian framework with commensurate priors addressing prior-data conflict. Trials were also more frequently concluded earlier in line with the underlying truth, reducing trial cost, and duration and yielded parameter estimates with smaller standard errors.

Randomized phase II trial of cixutumumab alone or with cetuximab for refractory recurrent/metastatic head and neck squamous cell carcinoma.

OBJECTIVES: Cixutumumab (CIX) and cetuximab (CET) monoclonal antibodies block ligand-binding to insulin-like growth factor-1 receptor (IGF-1R) and epidermal growth factor receptor (EGFR) respectively. The objective of this study was to assess the efficacy of CIX alone or combined with CET in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) patients. METHODS: In this open-label phase II trial, 91 R/M HNSCC patients who progressed within 90 days of platinum-based chemotherapy, were randomized to CIX 10 mg/kg alone or with CET 500 mg/m2 every 2 weeks. Patients were stratified by prior CET use. The primary endpoint was median progression-free survival (PFS). Exploratory biomarker assessments included relevant markers on archival tumor and serial cytokine/angiogenic-factor profiles in blood. RESULTS: Forty-seven patients were treated with CIX monotherapy and 44 with combination. The median PFS was 1.9 and 2.0 months and clinical benefit rate (complete or partial responses and stable disease) was 5.9% and 15.3%, respectively. There was no exacerbation of CET toxicity by concurrent CIX exposure. Higher tumor expression of IGF-1 was associated with improved PFS in the CIX + CET arm while increased p-EGFR expression correlated with shorter PFS in patients receiving single agent CIX. Higher serum baseline levels of IGF-1 and IGFBP-3 correlated with improved PFS and overall survival (OS) in the CIX arm. Neither regimen resulted in improved PFS or OS compared to historical data with CET alone. CONCLUSION: The results of this study do not support the use of cixutumumab alone or with cetuximab in unselected patients with R/M HNSCC.