Dynamic undirected graphical models for time-varying clinical symptom and neuroimaging networks.

In this work, we propose methods to examine how the complex interrelationships between clinical symptoms and, separately, brain imaging biomarkers change over time leading up to the diagnosis of a disease in subjects with a known genetic near-certainty of disease. We propose a time-dependent undirected graphical model that ensures temporal and structural smoothness across time-specific networks to examine the trajectories of interactions between markers aligned at the time of disease onset. Specifically, we anchor subjects relative to the time of disease diagnosis (anchoring time) as in a revival process, and we estimate networks at each time point of interest relative to the anchoring time. To use all available data, we apply kernel weights to borrow information across observations that are close to the time of interest. Adaptive lasso weights are introduced to encourage temporal smoothness in edge strength, while a novel elastic fused- l 0 $$ {l}_0 $$ penalty removes spurious edges and encourages temporal smoothness in network structure. Our approach can handle practical complications such as unbalanced visit times. We conduct simulation studies to compare our approach with existing methods. We then apply our method to data from PREDICT-HD, a large prospective observational study of pre-manifest Huntington's disease (HD) patients, to identify symptom and imaging network changes that precede clinical diagnosis of HD.

Registration of 24-hour accelerometric rest-activity profiles and its application to human chronotypes.

By collecting data continuously over 24 hours, accelerometers and other wearable devices can provide novel insights into circadian rhythms and their relationship to human health. Existing approaches for analyzing diurnal patterns using these data, including the cosinor model and functional principal components analysis, have revealed and quantified population-level diurnal patterns, but considerable subject-level variability remained uncaptured in features such as wake/sleep times and activity intensity. This remaining informative variability could provide a better understanding of chronotypes, or behavioral manifestations of one's underlying 24-hour rhythm. Curve registration, or alignment, is a technique in functional data analysis that separates "vertical" variability in activity intensity from "horizontal" variability in time-dependent markers like wake and sleep times; this data-driven approach is well-suited to studying chronotypes using accelerometer data. We develop a parametric registration framework for 24-hour accelerometric rest-activity profiles represented as dichotomized into epoch-level states of activity or rest. Specifically, we estimate subject-specific piecewise linear time-warping functions parametrized with a small set of parameters. We apply this method to data from the Baltimore Longitudinal Study of Aging and illustrate how estimated parameters give a more flexible quantification of chronotypes compared to traditional approaches.

Age of Onset of Huntington's Disease in Carriers of Reduced Penetrance Alleles.

BACKGROUND: Age of manifest Huntington's disease (HD) onset correlates with number of CAG repeats in the huntingtin gene. Little is known about onset with 36 to 39 repeats, the "reduced penetrance" (RP) range. OBJECTIVES: We provide allele-specific estimates of HD penetrance (diagnostic confidence level of 4) for RP allele carriers. METHODS: We analyzed 431 pre-manifest RP allele carriers from Enroll-HD, the largest prospective observational HD study. Cumulative penetrance (CP) was estimated from Kaplan-Meier curves. RESULTS: No one with 36 repeats (n = 25) phenoconverted. CP for 38 repeats (n = 120) was 32% (95% confidence interval [CI] 0%-55%) and 51% (CI, 10%-73%) by ages 70 and 75, respectively, and 68% (CI, 46%-81%) and 81% (CI, 58%-92%) by ages 70 and 75 for 39 repeats (n = 253). CP was not estimable at those ages for 37 repeats (n = 33). CONCLUSIONS: Differences by RP-range repeat length did not reach significance with a 3-year median follow-up duration among censored individuals. © 2021 International Parkinson and Movement Disorder Society.

Radiological and surgical implications of neoadjuvant treatment with FOLFIRINOX for locally advanced and borderline resectable pancreatic cancer.

PURPOSE: On the basis of the ACCORD trial, FOLFIRINOX is effective in metastatic pancreatic adenocarcinoma (PDAC), making it a rational choice for locally advanced PDAC (LA). Aims of this study are to evaluate the accuracy of imaging in determining the resectability of PDAC and to determine the surgical and clinicopathologic outcomes of pancreatic resections after neoadjuvant FOLFIRINOX therapy. PATIENTS AND METHODS: Clinicopathologic data were retrospectively collected for surgical PDAC patients receiving neoadjuvant FOLFIRINOX or no neoadjuvant therapy between April 2011 and February 2014. Americas Hepato-Pancreato-Biliary Association/Society of Surgical Oncology/Society for Surgery of the Alimentary Tract consensus guidelines defined LA and borderline. Imaging was reviewed by a blinded senior pancreatic surgeon. RESULTS: Of 188 patients undergoing resection for PDAC, 40 LA/borderline received FOLFIRINOX and 87 received no neoadjuvant therapy. FOLFIRINOX resulted in a significant decrease in tumor size, yet 19 patients were still classified as LA and 9 as borderline. Despite post-FOLFIRINOX imaging suggesting continued unresectability, 92% had an R0 resection. When compared with no neoadjuvant therapy, FOLFIRINOX resulted in significantly longer operative times (393 vs 300 minutes) and blood loss (600 vs 400 mL), but significantly lower operative morbidity (36% vs 63%) and no postoperative pancreatic fistulas. Length of stay (6 vs 7 days), readmissions (20% vs 30%), and mortality were equivalent (1% vs 0%). On final pathology, the FOLFIRINOX group had a significant decrease in lymph node positivity (35% vs 79%) and perineural invasion (72% vs 95%). Median follow-up was 11 months with a significant increase in overall survival with FOLFIRINOX. CONCLUSIONS: After neoadjuvant FOLFIRINOX imaging no longer predicts unresectability. Traditional pathologic predictors of survival are improved, and morbidity is decreased in comparison to patients with clearly resectable cancers at the time of presentation.

Nutrition and Bone Density in Boys with Autism Spectrum Disorder.

BACKGROUND: Boys with autism spectrum disorder (ASD) have lower bone mineral density (BMD) than typically developing controls. Differences in diet and exercise may contribute to low BMD. OBJECTIVE: Our aim was to examine macro- and micronutrient intakes and self-reported physical activity in boys with ASD compared to TDC and the relationship of these variables with BMD. DESIGN/METHODS: We conducted a cross-sectional study of 49 boys (25 ASD, 24 typically developing controls) assessed for 3-day food records and physical activity records, and BMD of the whole body less head, hip, and spine using dual-energy x-ray absorptiometry. Fasting levels of 25(OH) vitamin D and calcium were obtained. PARTICIPANTS: Participants were adolescent boys, aged 8 to 17 years, recruited from a clinic population (ASD) or community advertisements (ASD and typically developing controls) matched for age. RESULTS: ASD participants were approximately 9 months younger than typically developing control participants on average. Body mass index and serum vitamin D and calcium levels were similar. Boys with ASD consumed 16% fewer calories, with a larger percentage obtained from carbohydrates, and 37% less animal protein and 20% less fat than typically developing controls. A lower proportion of ASD participants were categorized as "very physically active" (27% vs 79%; P<0.001). BMD z scores were 0.7 to 1.2 standard deviations lower in ASD than typically developing controls at all locations. Higher animal protein, calcium, and phosphorus intakes were associated positively with bone density measures in boys with ASD. CONCLUSIONS: Compared to typically developing controls, boys with ASD had lower protein, calcium, and phosphorus intakes, activity levels, and BMD z scores at the lumbar spine, femoral neck, total hip, and whole body less head. Protein, calcium, and phosphorus intakes were associated positively with BMD.

Phase II Study of Proton-Based Stereotactic Body Radiation Therapy for Liver Metastases: Importance of Tumor Genotype.

Background: We evaluated the efficacy and safety of risk-adapted, proton-based stereotactic body radiation therapy (SBRT) for liver metastases from solid tumors. Methods: This single-arm phase II single institutional study (NCT01239381) included patients with limited extrahepatic disease, 800 mL or greater of uninvolved liver, and no cirrhosis or Child-Pugh A, who had received proton-based SBRT to one to four liver metastases from solid tumors. Treatment comprised 30 to 50 Gray equivalent (GyE) in five fractions based on the effective volume of liver irradiated. Sample size was calculated to determine if local control (LC) at one year was greater than 70%. The cumulative incidence of local failure was used to estimate LC. The association of tumor characteristics, including genetic alterations in common cancer genes such as BRAF, EGFR, HER2, KRAS, NRAS, PIK3CA, and TP53 with local tumor control, was assessed. All statistical tests were two-sided. Results: Eighty-nine patients were evaluable (colorectal, n = 34; pancreatic, n = 13; esophagogastric, n = 12; other, n = 30). Median tumor size was 2.5 cm (range = 0.5-11.9 cm). Median dose was 40 GyE (range = 30-50 GyE), and median follow-up was 30.1 months (range = 14.7-53.8 months). There was no grade 3 to 5 toxicity. Median survival time was 18.1 months. The one- and three-year LC rates were 71.9% (95% confidence limit [CL] = 62.3% to 80.9%) and 61.2% (95% CL = 50.8% to 71.8%), respectively. For large tumors (≥6 cm), one-year LC remained high at 73.9% (95% CL = 54.6% to 89.8%). Mutation in the KRAS oncogene was the strongest predictor of poor LC (P = .02). Tumor with both mutant KRAS and TP53 were particularly radioresistant, with a one-year LC rate of only 20.0%, compared with 69.2% for all others (P = .001). Conclusions: We report the largest prospective evaluation to date of liver SBRT for hepatic metastases, and the first with protons. Protons were remarkably well tolerated and effective even for metastases that were 6 cm or larger. KRAS mutation is a strong predictor of poor LC, stressing the need for tumor genotyping prior to SBRT and treatment intensification in this patient subset.

Multi-Institutional Phase II Study of High-Dose Hypofractionated Proton Beam Therapy in Patients With Localized, Unresectable Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma.

PURPOSE: To evaluate the efficacy and safety of high-dose, hypofractionated proton beam therapy for hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). MATERIALS AND METHODS: In this single-arm, phase II, multi-institutional study, 92 patients with biopsy-confirmed HCC or ICC, determined to be unresectable by multidisciplinary review, with a Child-Turcotte-Pugh score (CTP) of A or B, ECOG performance status of 0 to 2, no extrahepatic disease, and no prior radiation received 15 fractions of proton therapy to a maximum total dose of 67.5 Gy equivalent. Sample size was calculated to demonstrate > 80% local control (LC) defined by Response Evaluation Criteria in Solid Tumors (RECIST) 1.0 criteria at 2 years for HCC patients, with the parallel goal of obtaining acceptable precision for estimating outcomes for ICC. RESULTS: Eighty-three patients were evaluable: 44 with HCC, 37 with ICC, and two with mixed HCC/ICC. The CTP score was A for 79.5% of patients and B for 15.7%; 4.8% of patients had no cirrhosis. Prior treatment had been given to 31.8% of HCC patients and 61.5% of ICC patients. The median maximum dimension was 5.0 cm (range, 1.9 to 12.0 cm) for HCC patients and 6.0 cm (range, 2.2 to 10.9 cm) for ICC patients. Multiple tumors were present in 27.3% of HCC patients and in 12.8% of ICC patients. Tumor vascular thrombosis was present in 29.5% of HCC patients and in 28.2% of ICC patients. The median dose delivered to both HCC and ICC patients was 58.0 Gy. With a median follow-up among survivors of 19.5 months, the LC rate at 2 years was 94.8% for HCC and 94.1% for ICC. The overall survival rate at 2 years was 63.2% for HCC and 46.5% ICC. CONCLUSION: High-dose hypofractionated proton therapy demonstrated high LC rates for HCC and ICC safely, supporting ongoing phase III trials of radiation in HCC and ICC.