Glycemia and Gluconeogenesis With Metformin and Liraglutide: A Randomized Trial in Youth-onset Type 2 Diabetes.

OBJECTIVE: Elevated rates of gluconeogenesis are an early pathogenic feature of youth-onset type 2 diabetes (Y-T2D), but targeted first-line therapies are suboptimal, especially in African American (AA) youth. We evaluated glucose-lowering mechanisms of metformin and liraglutide by measuring rates of gluconeogenesis and ß-cell function after therapy in AA Y-T2D. METHODS: In this parallel randomized clinical trial, 22 youth with Y-T2D-age 15.3 ± 2.1 years (mean ± SD), 68% female, body mass index (BMI) 40.1 ± 7.9 kg/m2, duration of diagnosis 1.8 ± 1.3 years-were randomized to metformin alone (Met) or metformin + liraglutide (Lira) (Met + Lira) and evaluated before and after 12 weeks. Stable isotope tracers were used to measure gluconeogenesis [2H2O] and glucose production [6,6-2H2]glucose after an overnight fast and during a continuous meal. ß-cell function (sigma) and whole-body insulin sensitivity (mSI) were assessed during a frequently sampled 2-hour oral glucose tolerance test. RESULTS: At baseline, gluconeogenesis, glucose production, and fasting and 2-hour glucose were comparable in both groups, though Met + Lira had higher hemoglobin A1C. Met + Lira had a greater decrease from baseline in fasting glucose (-2.0 ± 1.3 vs -0.6 ± 0.9 mmol/L, P = .008) and a greater increase in sigma (0.72 ± 0.68 vs -0.05 ± 0.71, P = .03). The change in fractional gluconeogenesis was similar between groups (Met + Lira: -0.36 ± 9.4 vs Met: 0.04 ± 12.3%, P = .9), and there were no changes in prandial gluconeogenesis or mSI. Increased glucose clearance in both groups was related to sigma (r = 0.63, P = .003) but not gluconeogenesis or mSI. CONCLUSION: Among Y-T2D, metformin with or without liraglutide improved glycemia but did not suppress high rates of gluconeogenesis. Novel therapies that will enhance ß-cell function and target the elevated rates of gluconeogenesis in Y-T2D are needed.

Reevaluating First-line Therapies in Youth-Onset Type 2 Diabetes.

The prevalence of youth-onset type 2 diabetes is growing worldwide and current first-line treatment with metformin and intensive behavior and lifestyle changes are suboptimal in over 50% of youth within 2 years of diagnosis. This perspective article is a call to action for reevaluation of existing strategies and critical appraisal of metformin as first-line therapy in youth-onset type 2 diabetes. Increased attention should be given to novel therapeutics approved in youth, including glucagon-like 1 receptor agonists, sodium glucose cotransporter-2, and sociocultural interventions that will promote diabetes self-management.

The Incidence and Prevalence of Primary Central Nervous System (CNS) Tumours in Canada (2010-2017), and the Survival of Patients Diagnosed with CNS Tumours (2008-2017).

Primary central nervous system (CNS) tumours are heterogeneous, with different treatment pathways and prognoses depending on their histological and molecular classification. Due to their anatomical location, all CNS tumours, regardless of malignancy, can be debilitating. We used vital statistics linked to Canadian Cancer Registry data to estimate the age-standardized incidence rates (ASIR), Kaplan-Meier survival rates (SR), and limited-duration prevalence proportions (PP) of 25 histology-specific CNS tumour groups that were classified based on site and histology. During 2010-2017, 45,115 patients were diagnosed with 47,085 primary CNS tumours, of which 19.0% were unclassified. The average annual ASIR was 21.48/100,000 person-years and did not vary by sex. The ASIR increased with age, particularly for meningioma, unclassified tumours, and glioblastoma. The eight-year PP was 102.1/100,000 persons (index date 1 January 2018). The most common histology was meningioma (ASIR: 5.19; PP: 31.6). The overall five-year SR among 51,310 patients diagnosed during 2008-2017 was 57.2% (95% CI: 56.8-57.7%). SRs varied by tumour behaviour, histology, and patient age, with the lowest SR among glioblastoma patients (5-year SRs ranged from 1.3-25.7%). For non-malignant tumours, the 5-year SRs ranged from 37.4-100%. We provide the most up-to-date histology-specific surveillance estimates for primary CNS tumours in Canada.

Incidence and survival of primary central nervous system tumors diagnosed in 4 Canadian provinces from 2010 to 2015.

Background: The Brain Tumor Registry of Canada was established in 2016 to enhance infrastructure for surveillance and clinical research on Central Nervous System (CNS) tumors. We present information on primary CNS tumors diagnosed among residents of Canada from 2010 to 2015. Methods: Data from 4 provincial cancer registries were analyzed representing approximately 67% of the Canadian population. Age-standardized incidence rates (ASIR) and 95% confidence intervals (CI) were calculated using the 2011 Canadian population age distribution. Net survival was estimated using the Pohar-Perme method. Results: A total of 31 644 primary tumors were identified for an ASIR of 22.8 per 100 000 person-years. Nonmalignant tumors made up 47.1% of all classified tumors, with mixed behaviors present in over half of histology groupings. Unclassified were 19.5% of all tumors. The most common histological subtypes are meningiomas (ASIR = 5.5 per 100 000 person-years); followed by glioblastomas (ASIR 4.0 per 100 000 person-years). The overall 5-year net survival rate for CNS tumors was 65.5%; females 70.2% and males 60.4%. GBMs continue to be the most lethal CNS tumors for all sex and age groups. Conclusions: The low annual frequency of most CNS tumor subtypes emphasizes the value of population-based data on all primary CNS tumors diagnosed among Canadians. The large number of histological categories including mixed behaviors and the proportion of unclassified tumors emphasizes the need for complete reporting. Variation in incidence and survival across histological groups by sex and age highlights the need for comprehensive and histology-specific reporting. These data can be used to better inform research and health system planning.

Genome Sequences of Streptomyces Bacteriophages Fabian, FlowerPower, Geostin, RetrieverFever, and Vorvolakos.

This paper reports the genome sequences of five bacteriophages that were isolated using Streptomyces scabiei. Phages Fabian, FlowerPower, Geostin, RetrieverFever, and Vorvolakos were assigned to actinobacteriophage cluster BF based on shared gene content, with each phage containing between 16 and 21 tRNA genes.

Brain Metastases among Cancer Patients Diagnosed from 2010-2017 in Canada: Incidence Proportion at Diagnosis and Estimated Lifetime Incidence.

The incidence of BM among Canadian cancer patients is unknown. We aimed to estimate IP of BM at the time of cancer diagnosis and during the lifetime of patients with selected primary cancers. Data on BM at diagnosis from 2010-2017 was obtained from the CCR. Site-specific IPs of BM were estimated from provincial registries containing ≥90% complete data on BM. The CCR IP estimates and the IP estimates from literature were applied to the total diagnosed primary cancers to estimate the number of concurrent BM and lifetime BM from 2010-2017 in Canada, respectively. The annual average number of patients with BM at diagnosis from all cancer sites was approximately 3227. The site-specific IPs of BM at diagnosis were: lung (9.42%; 95% CI: 9.16-9.68%), esophageal (1.58%; 95% CI: 1.15-2.02%), kidney/renal pelvis (1.33%; 95% CI: 1.12-1.54%), skin melanoma (0.73%; 95% CI: 0.61-0.84%), colorectal (0.22%; 95% CI: 0.18-0.26%), and breast (0.21%; 95% CI: 0.17-0.24%). Approximately 76,546 lifetime BM cases (or 5.70% of selected fifteen primary cancers sites) were estimated to have occurred from the 2010-2017 cancer patient cohort. These findings reflect results of population analyses in the US and Denmark. We recommend improved standardization of the collection of BM data within the CCR.

Head and neck squamous cell carcinomas among males of the three largest Asian diasporas in the US, 2004-2013.

BACKGROUND: Head and neck squamous cell carcinomas (HNSCC) have not been fully examined in the Asian diasporas in the US, despite certain Asian countries having the highest incidence of specific HNSCCs. METHODS: National Cancer Database was used to compare 1046 Chinese, 887 South Asian (Indian/Pakistani), and 499 Filipino males to 156,927 Non-Hispanic White (NHW) males diagnosed with HNSCC between 2004-2013. Multinomial logistic regression was used to assess the association of race/ethnicity with two outcomes - site group and late-stage diagnosis. Temporal trends were explored for site groups and subsites. RESULTS: South Asians had a greater proportion of oral cavity cancer [OCC] compared to NHWs (59 % vs. 25 %; ORadj =7.3 (95 % CI: 5.9-9.0)). In contrast, Chinese (64 % vs. 9%; ORadj =34.0 (95 % CI: 26.5-43.6)) and Filipinos (47 % vs. 9%; ORadj =10.0 (95 % CI: 7.8-12.9)) had a greater proportion of non-oropharyngeal cancer compared to NHWs. All three Asian subgroups had a higher likelihood of being diagnosed by age 40 (14 % Chinese, 10 % South Asian and 8% Filipino compared to 3% in NHW; p < 0.001). Chinese males had lower odds of late-stage diagnosis, compared to NHWs. South Asian cases doubled from 2004 to 2013 largely due to an increase in OCC cases (34 cases in 2004 to 86 in 2013). CONCLUSION: Asian diasporas are at a higher likelihood of specific HNSCCs. Risk factors, screening and survival need to be studied further, and policy changes are needed to promote screening and to discourage high-risk habits in these Asian subgroups.

Clinical Uncertainty and Equipoise in the Management of Recurrent Glioblastoma.

BACKGROUND: A significant proportion of glioblastoma (GBM) patients are considered for repeat resection, but evidence regarding best management remains elusive. Our aim was to measure the degree of clinical uncertainty regarding reoperation for patients with recurrent GBM. METHODS: We first performed a systematic review of agreement studies examining the question of repeat resection for recurrent GBM. An electronic portfolio of 37 pathologically confirmed recurrent GBM patients including pertinent magnetic resonance images and clinical information was assembled. To measure clinical uncertainty, 26 neurosurgeons from various countries, training backgrounds, and years' experience were asked to select best management (repeat surgery, other nonsurgical management, or conservative), confidence in recommended management, and whether they would include the patient in a randomized trial comparing surgery with nonsurgical options. Agreement was evaluated using κ statistics. RESULTS: The literature review did not reveal previous agreement studies examining the question. In our study, agreement regarding best management of recurrent GBM was slight, even when management options were dichotomized (repeat surgery vs. other options; κ=0.198 [95% confidence interval: 0.133-0.276]). Country of practice, years' experience, and training background did not change results. Disagreement and clinical uncertainty were more pronounced within clinicians with (κ=0.167 [0.055-0.314]) than clinicians without neuro-oncology fellowship training (κ=0.601 [0.556-0.646]). A majority (51%) of responders were willing to include the patient in a randomized trial comparing repeat surgery with nonsurgical alternatives in 26/37 (69%) of cases. CONCLUSION: There is sufficient uncertainty and equipoise regarding the question of reoperation for patients with recurrent glioblastoma to support the need for a randomized controlled trial.

The Importance of Cancer Registry Linkage for Studying Rare Cancers in Prospective Cohorts.

Large prospective cohort studies may offer an opportunity to study the etiology and natural history of rare cancers. Cancer diagnoses in observational cohort studies are often self-reported. Little information exists on the validity of self-reported cancer diagnosis, especially rare cancers, in Canada. This study evaluated the validity of self-reported cancer diagnosis in Alberta's Tomorrow Project (ATP), a provincial cohort in Canada. ATP data were linked to the Alberta Cancer Registry (ACR). The first instance of self-reported cancer in a follow-up survey was compared to the first cancer diagnosis in the ACR after enrollment. The sensitivity and positive predictive value (PPV) were estimated for the reporting of cancer status, reporting of common or rare cancer, and reporting of site-specific cancer. Logistic regression analysis explored factors associated with false positive, false negative, and incorrect cancer site reporting. In the 30,843 ATP participants who consented to registry linkage, there were 810 primary cancer diagnoses in the ACR and 959 self-reports of first cancer post-enrollment, for a cancer status sensitivity of 92.1% (95% CI: 90.0-93.9) and PPV of 77.8% (95% CI: 75.0-80.4). Compared to common cancers, rare cancers had a lower sensitivity (62.8% vs. 89.6%) and PPV (35.8% vs. 84.5%). Participants with a rare cancer were more likely to report an incorrect site than those with a common cancer. Rare cancers were less likely to be captured by active follow-up than common cancers. While rare cancer research may be feasible in large cohort studies, registry linkage is necessary to capture rare cancer diagnoses completely and accurately.

A machine learning approach to predict ethnicity using personal name and census location in Canada.

BACKGROUND: Canada is an ethnically-diverse country, yet its lack of ethnicity information in many large databases impedes effective population research and interventions. Automated ethnicity classification using machine learning has shown potential to address this data gap but its performance in Canada is largely unknown. This study conducted a large-scale machine learning framework to predict ethnicity using a novel set of name and census location features. METHODS: Using census 1901, the multiclass and binary class classification machine learning pipelines were developed. The 13 ethnic categories examined were Aboriginal (First Nations, Métis, Inuit, and all-combined)), Chinese, English, French, Irish, Italian, Japanese, Russian, Scottish, and others. Machine learning algorithms included regularized logistic regression, C-support vector, and naïve Bayes classifiers. Name features consisted of the entire name string, substrings, double-metaphones, and various name-entity patterns, while location features consisted of the entire location string and substrings of province, district, and subdistrict. Predictive performance metrics included sensitivity, specificity, positive predictive value, negative predictive value, F1, Area Under the Curve for Receiver Operating Characteristic curve, and accuracy. RESULTS: The census had 4,812,958 unique individuals. For multiclass classification, the highest performance achieved was 76% F1 and 91% accuracy. For binary classifications for Chinese, French, Italian, Japanese, Russian, and others, the F1 ranged 68-95% (median 87%). The lower performance for English, Irish, and Scottish (F1 ranged 63-67%) was likely due to their shared cultural and linguistic heritage. Adding census location features to the name-based models strongly improved the prediction in Aboriginal classification (F1 increased from 50% to 84%). CONCLUSIONS: The automated machine learning approach using only name and census location features can predict the ethnicity of Canadians with varying performance by specific ethnic categories.

Ovarian Cancer in Women of African Ancestry (OCWAA) consortium: a resource of harmonized data from eight epidemiologic studies of African American and white women.

PURPOSE: Although the incidence rate of epithelial ovarian cancer (EOC) is somewhat lower in African American (AA) than white women, survival is worse. The Ovarian Cancer in Women of African Ancestry (OCWAA) consortium will overcome small, study-specific sample sizes to better understand racial differences in EOC risk and outcomes. METHODS: We harmonized risk factors and prognostic characteristics from eight U.S. STUDIES: the North Carolina Ovarian Cancer Study (NCOCS), the Los Angeles County Ovarian Cancer Study (LACOCS), the African American Cancer Epidemiology Study (AACES), the Cook County Case-Control Study (CCCCS), the Black Women's Health Study (BWHS), the Women's Health Initiative (WHI), the Multiethnic Cohort Study (MEC), and the Southern Community Cohort Study (SCCS). RESULTS: Determinants of disparities for risk and survival in 1,146 AA EOC cases and 2,922 AA controls will be compared to 3,368 white EOC cases and 10,270 white controls. Analyses include estimation of population-attributable risk percent (PAR%) by race. CONCLUSION: OCWAA is uniquely positioned to study the epidemiology of EOC in AA women compared with white women to address disparities. Studies of EOC have been underpowered to address factors that may explain AA-white differences in the incidence and survival. OCWAA promises to provide novel insight into disparities in ovarian cancer.

Malignant primary brain and other central nervous system tumors diagnosed in Canada from 2009 to 2013.

BACKGROUND: We present a national surveillance report on malignant primary brain and other central nervous system (CNS) tumors diagnosed in the Canadian population in 2009-2013. METHODS: Patients were identified through the Canadian Cancer Registry, an administrative dataset that includes cancer incidence data from all provinces/territories in Canada. Tumor types were classified by site and histology using the definitions from the Central Brain Tumor Registry of the United States (CBTRUS). Incidence rates (IRs) and 95% confidence intervals (CIs) were calculated per 100000 person-years (py) and age-standardized to the 2011 Canadian population for comparisons within Canada and to the 2000 United States population for comparisons with the US. RESULTS: Overall, 12515 malignant brain and other CNS tumors were diagnosed in the Canadian population in 2009-2013 (IR: 8.71/100000 py; 95% CI: 8.56, 8.86); 7085 were among males (IR: 10.06/100000 py; 95% CI: 9.82, 10.29) and 5430 among females (IR: 7.41/100000 py; 95% CI: 7.22, 7.61). Of these, 12115 were classifiable according to histological subgroups defined by CBTRUS. The most common histology was glioblastoma (IR: 4.06/100000 py; 95% CI: 3.95, 4.16). Among those aged 0-19 years, 1130 malignant brain and CNS tumors were diagnosed in 2009-2013 (IR: 3.36/100000 py; 95% CI: 3.16, 3.56). The most common histology among the pediatric population was embryonal tumor (IR: 0.74/100000 py; 95% CI: 0.65, 0.84). CONCLUSIONS: These data represent an initial detailed report on the frequency and distribution of primary malignant brain and other CNS tumors diagnosed in the Canadian population in 2009-2013. The reported distributions of tumor diagnoses by sex and age reflected expected patterns based on the literature from similar populations. A report incorporating data on nonmalignant primary brain tumors is forthcoming.

Renal cell carcinoma risk associated with lower intake of micronutrients.

Kidney cancer incidence in African Americans (AA) is higher than among European Americans (EA); reasons for this disparity are not fully known. Dietary micronutrients may have a protective effect on renal cell carcinoma (RCC) development by inhibiting oxidative DNA damage and tumor growth. We evaluated whether any micronutrient associations differed by race in the US Kidney Cancer Study. 1142 EA and AA RCC cases and 1154 frequency-matched controls were enrolled in a population-based case-control study between 2002 and 2007. Dietary micronutrient intake was derived from an interviewer-administered diet history questionnaire. RCC risk associated with micronutrient intake was estimated using adjusted odds ratios from logistic regression comparing lower to highest quartiles of intake and sample weighting. Inverse associations with RCC risk were observed for α-carotene, ß-carotene, lutein zeaxanthin, lycopene, vitamin A, folate, thiamin, vitamin C, α-tocopherol, ß-tocopherol, γ-tocopherol, and selenium. A trend for ß-cryptoxanthin was suggested among EA but not AA or the total sample (P-interaction = .04). Otherwise, findings did not differ by race, gender, age, or smoking status. The increase in RCC risk associated with lower micronutrient intake is similar within AA and EA populations. A diet rich in sources of micronutrients found in fruits, vegetables, and nuts may help to reduce the overall risk of RCC.

Application of mutagen sensitivity assay in a glioma case-control study.

Few risk factors for glioma have been identified other than ionizing radiation. The alkylating agent acrylamide is a compound found in both occupational and the general environment and identified as one of the forty known or suspected neurocarcinogens in animal models. The mutagen sensitivity assay (MSA) has been used to indirectly show reduced DNA repair capacity upon exposure to ionizing radiation in those with glioma compared to controls. In this study, MSA was used to assess its applicability to a glioma case-control study and to test the hypothesis that subjects with glioma may have lower DNA repair capacity after exposure to selected potential human neurocarcinogens (i.e. acrylamide), compared to controls. Approximately 50 case and 50 control subjects were identified from a clinic-based study that investigated environmental risk factors for glioma, who completed an exposure survey, and had frozen immortalized lymphocytes available. A total of 50 metaphase spreads were read and reported for each participant. The association of case-control status with MSA for acrylamide, i.e. breaks per spread, was examined by multivariable logistic regression models. The mean number of breaks per slide was similar between hospital-based controls and cases. In addition, case-control status or exposure categories were not associated with the number of breaks per spread. Although the MSA has been shown as a useful molecular epidemiology tool for identifying individuals at higher risk for cancer, our data do not support the hypothesis that glioma patients have reduced DNA repair capacity in response to exposure to acrylamide. Further research is needed before the MSA is utilized in large-scale epidemiological investigations of alkylating agents.

On Capturing Radiological Diagnoses of Brain Tumors to Provide Complete Population Data in Cancer Registries in Canada.

Nonmalignant brain tumors are underreported by an estimated 60% in Canadian cancer registries. One explanation is that radiology facilities or their databases may not be adequately included in the cancer reporting infrastructure. A multidisciplinary stakeholder team met for 1 day, followed by teleconferences, to discuss the evidence for the importance of incorporating radiology diagnoses in brain tumor reports. A role for the neuroradiologist was delineated in brain tumor diagnosis and in ensuring that radiology report information is available to support cancer case ascertainment in the cancer surveillance system. It was noted that brain tumors identified through imaging are clinically managed depending on the diagnosis and prognosis of the disease, and that patient radiology reports become a part of a larger administrative information system. The proportion of nonmalignant brain tumors diagnosed using histology is lower in the United States (49.3%) than in Canada (59%), suggesting that a higher proportion of cases with nonhistologic (likely radiology) diagnosis are captured by the US system (eg, tumors of the sellar region, cranial and spinal tumors, and tumors of the meninges). Finding a way to use existing electronic radiology reports to identify nonmalignant brain tumors needs to be prioritized. This will require access to electronic radiology reports, as manual reporting is impractical. Once access is achieved, an electronic flag to identify new cases through a natural language processing algorithm could be pursued. As radiologists and cancer registrars become more familiar with each other's mandates and workflow demands, innovative and collaborative solutions to improve case ascertainment for brain and other cancers are likely to emerge.

The Impact of Hospital Discharge Linkage on Case Ascertainment of Brain Tumors in the Alberta Cancer Registry, 2010-2015.

BACKGROUND: Concern has been raised regarding the underreporting of nonmalignant central nervous system tumors. This study addressed this issue with 2 objectives: (1) evaluate the impact of linkage with hospital discharges, as recorded in the Discharge Abstract Database (DAD), on supplementing case ascertainment for brain tumors, and (2) identify potential barriers for initial registration of brain tumors in the Alberta Cancer Registry. METHODS: All patients with a brain tumor diagnosed and residing in Alberta from 2010 to 2015 were extracted, after the DAD review, from the Alberta Cancer Registry (ACR). Descriptive statistics were compiled by behavior and type of registration (originally registered or identified through DAD). The total number of expected nonmalignant brain tumors was estimated by applying the Central Brain Tumor Registry of the United States (CBTRUS) incidence rates to the Alberta population and this estimate was compared to observed numbers. Phi coefficients and χ2 tests for the homogeneity of proportions were conducted to examine bivariate relationships of the characteristics of interest. Multiple logistic regression was used to summarize the independent effects on the probability of being identified through DAD. RESULTS: The results show 5% of malignant and 35% of nonmalignant brain tumors were identified through DAD review. When comparing observed to expected number of nonmalignant cases after DAD review, the ACR ultimately captured 76% of those expected. Identification through DAD was statistically significantly (P ≤ .05) associated with patients over 75 years old at diagnosis (odds ratio [OR], 2.5), tumors of benign behavior (OR, 2.6), location at diagnosis in Northern Alberta (OR, 1.5), nonmicroscopically confirmed tumors (OR, 1.3), no visit to a CancerControl Alberta facility (OR, 8.7) and certain histological subtypes, including cranial and spinal nerve tumors (OR, 1.7). CONCLUSION: The use of hospital discharge data significantly improved nonmalignant brain tumor case ascertainment. Therefore, it is recommended that such reviews be instituted annually in provinces while other techniques (such as reminder letters used in Norway or linkages with radiology or other administrative databases) for improving case ascertainment are explored. Those characteristics identified as potential barriers to registration should be investigated to identify possible process improvements in Alberta.