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Dive into the research topics where Gary Chisholm is active.

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Featured researches published by Gary Chisholm.


Cancer | 2014

Impact of timing and setting of palliative care referral on quality of end-of-life care in cancer patients.

David Hui; Sun Hyun Kim; Joyce Roquemore; Rony Dev; Gary Chisholm; Eduardo Bruera

Limited data are available on how the timing and setting of palliative care (PC) referral can affect end‐of‐life care. In this retrospective cohort study, the authors examined how the timing and setting of PC referral were associated with the quality of end‐of‐life care.


Epidemiologic Reviews | 2014

Body Mass Index and Breast Cancer Risk According to Postmenopausal Estrogen-Progestin Use and Hormone Receptor Status

Mark F. Munsell; Brian L. Sprague; Donald A. Berry; Gary Chisholm; Amy Trentham-Dietz

To assess the joint relationships among body mass index, menopausal status, and breast cancer according to breast cancer subtype and estrogen-progestin medication use, we conducted a meta-analysis of 89 epidemiologic reports published in English during 1980-2012 identified through a systematic search of bibliographic databases. Pooled analysis yielded a summary risk ratio of 0.78 (95% confidence interval (CI): 0.67, 0.92) for hormone receptor-positive premenopausal breast cancer associated with obesity (body mass index (weight (kg)/height (m)(2)) ≥30 compared with <25). Obesity was associated with a summary risk ratio of 1.39 (95% CI: 1.14, 1.70) for receptor-positive postmenopausal breast cancer. For receptor-negative breast cancer, the summary risk ratios of 1.06 (95% CI: 0.70, 1.60) and 0.98 (95% CI: 0.78, 1.22) associated with obesity were null for both premenopausal and postmenopausal women, respectively. Elevated postmenopausal breast cancer risk ratios associated with obesity were limited to women who never took estrogen-progestin therapy, with risk ratios of 1.42 (95% CI: 1.30, 1.55) among never users and 1.18 (95% CI: 0.98, 1.42) among users; too few studies were available to examine this relationship according to receptor subtype. Future research is needed to confirm whether obesity is unrelated to receptor-negative breast cancer in populations of postmenopausal women with low prevalence of hormone medication use.


Oncologist | 2012

Access to Palliative Care Among Patients Treated at a Comprehensive Cancer Center

David Hui; Sun Hyun Kim; Jung Hye Kwon; Kimberson Tanco; Tao Zhang; Jung Hun Kang; Wadih Rhondali; Gary Chisholm; Eduardo Bruera

BACKGROUND Palliative care (PC) is a critical component of comprehensive cancer care. Previous studies on PC access have mostly examined the timing of PC referral. The proportion of patients who actually receive PC is unclear. We determined the proportion of cancer patients who received PC at our comprehensive cancer center and the predictors of PC referral. METHODS We reviewed the charts of consecutive patients with advanced cancer from the Houston region seen at MD Anderson Cancer Center who died between September 2009 and February 2010. We compared patients who received PC services with those who did not receive PC services before death. RESULTS In total, 366 of 816 (45%) decedents had a PC consultation. The median interval between PC consultation and death was 1.4 months (interquartile range, 0.5-4.2 months) and the median number of medical team encounters before PC was 20 (interquartile range, 6-45). On multivariate analysis, older age, being married, and specific cancer types (gynecologic, lung, and head and neck) were significantly associated with a PC referral. Patients with hematologic malignancies had significantly fewer PC referrals (33%), the longest interval between an advanced cancer diagnosis and PC consultation (median, 16 months), the shortest interval between PC consultation and death (median, 0.4 months), and one of the largest numbers of medical team encounters (median, 38) before PC. CONCLUSIONS We found that a majority of cancer patients at our cancer center did not access PC before they died. PC referral occurs late in the disease process with many missed opportunities for referral.


Annals of Internal Medicine | 2016

Collaborative Modeling of the Benefits and Harms Associated With Different U.S. Breast Cancer Screening Strategies.

Jeanne S. Mandelblatt; Natasha K. Stout; Clyde B. Schechter; Jeroen J. van den Broek; Diana L. Miglioretti; Martin Krapcho; Amy Trentham-Dietz; Diego F. Munoz; Sandra J. Lee; Donald A. Berry; Nicolien T. van Ravesteyn; Oguzhan Alagoz; Karla Kerlikowske; Anna N. A. Tosteson; Aimee M. Near; Amanda Hoeffken; Yaojen Chang; Eveline A.M. Heijnsdijk; Gary Chisholm; Xuelin Huang; Hui Huang; Mehmet Ali Ergun; Ronald E. Gangnon; Brian L. Sprague; Sylvia K. Plevritis; Eric J. Feuer; Harry J. de Koning; Kathleen A. Cronin

Context Multiple alternative mammography screening strategies exist. Contribution This modeling study estimated outcomes of 8 strategies that differed by starting age and interval. Biennial screening from age 50 to 74 years avoided a median of 7 breast cancer deaths; in contrast, annual screening from age 40 to 74 years avoided an additional 3 deaths but yielded 1988 more false-positive results and 11 more overdiagnoses per 1000 women screened. Annual screening from age 40 years for high-risk women had similar outcomes as screening average-risk women biennially from 50 to 74 years of age. Caution Imaging technologies other than mammography and nonadherence were not modeled. Implication Biennial mammography screening for breast cancer is efficient for average-risk women. Despite decades of mammography screening for early detection of breast cancer, there is no consensus on optimal strategies, target populations, or the magnitude of harms and benefits (111). The 2009 US Preventive Services Task Force (USPSTF) recommended biennial film mammography from age 50 to 74 years and suggested shared decision making about screening for women in their 40s (12). Since that recommendation was formulated, new data on the benefits of screening have emerged (2, 6, 8, 9, 11, 13, 14), digital mammography has essentially replaced plain film (15), and increasingly effective systemic treatment regimens for breast cancer have become standard (16). There has also been growing interest in consumer preferences and personalized screening approaches (1720). These factors could each affect the outcomes of breast cancer screening programs or alter policy decisions about population screening strategies (17). Modeling can inform screening policy decisions because it uses the best available evidence to evaluate a wide range of strategies while holding selected conditions (such as treatment effects) constant, facilitating strategy comparisons (21, 22). Modeling also provides a quantitative summary of outcomes in different groups and assesses how preferences affect results. Collaboration of several models provides a range of plausible effects and illustrates the effects of differences in model assumptions on results (1, 7, 23). We used 6 well-established simulation models to synthesize current data and examine the outcomes of digital mammography screening at various starting ages and intervals among average-risk women. We also examined how breast density, risk, or comorbidity levels affect results and whether preferences for health states related to screening and its downstream consequences affected conclusions. Methods Strategies We evaluated 8 strategies that varied by starting age (40, 45, or 50 years) and interval (annual, biennial, and hybrid [annual for women in their 40s and biennial thereafter]); all strategies stop screening at age 74 years. We included no screening as a baseline. Model Descriptions The models used to evaluate the screening strategies were developed within the Cancer Intervention and Surveillance Modeling Network (CISNET) (2430), and the research was institutional review boardapproved. They were named model D (Dana-Farber Cancer Institute, Boston, Massachusetts), model E (Erasmus MC, University Medical Center Rotterdam, Rotterdam, the Netherlands), model GE (Georgetown University Medical Center, Washington, DC, and Albert Einstein College of Medicine, Bronx, New York), model M (MD Anderson Cancer Center, Houston, Texas), model S (Stanford University, Stanford, California), and model W (University of Wisconsin, Madison, Wisconsin, and Harvard Medical School, Boston, Massachusetts). The Appendix provides information on model validation. Since earlier analyses (1), the models have undergone substantial revision to reflect advances in breast cancer control, including portrayal of molecular subtypes based on estrogen receptor (ER) and human epidermal growth factor-2 receptor (HER2) status (23); current population incidence (31) and competing nonbreast cancer mortality; digital screening; and the most current therapies (32). All models except model S include ductal carcinoma in situ (DCIS). The general modeling approach is summarized in this article; full details, including approach, construction, data sources, assumptions, and implementation, are available at https://resources.cisnet.cancer.gov/registry and reference 33. Additional information is available on request, and the models are available for use via collaboration. The models begin with estimates of breast cancer incidence (31) and ER/HER2-specific survival trends without screening or adjuvant treatment, and then overlay data on screening and molecular subtypespecific adjuvant treatment to generate observed incidence and breast cancerspecific mortality trends in the U.S. population (1, 7, 17, 23, 33, 34). Breast cancer has a distribution of preclinical screen-detectable periods (sojourn time) and clinical detection points. Performance characteristics of digital mammography depend on age, first versus subsequent screen, time since last mammogram, and breast density. ER/HER2 status is assigned at diagnosis on the basis of stage and age. Molecular subtype and stage-specific treatment reduces the hazard of breast cancer death (models D, GE, M, and S) or results in a cure for some cases (models E and W). Women can die of breast cancer or other causes. Screen detection of cancer during the preclinical screen-detectable period can result in the identification and treatment of earlier-stage or smaller tumors than might occur via clinical detection, with a corresponding reduction in breast cancer mortality. We used a cohort of women born in 1970 with average-risk and average breast density and followed them from age 25 years (because breast cancer is rare before this age [0.08% of cases]) until death or age 100 years. Model Input Parameters The models used a common set of age-specific variables for breast cancer incidence, performance of digital mammography, treatment effects, and average and comorbidity-specific nonbreast cancer causes of death (20, 35). The parameter values are available at www.uspreventiveservicestaskforce.org/Page/Document/modeling-report-collaborative-modeling-of-us-breast-cancer-1/breast-cancer-screening1 (33). In addition, each group included model-specific inputs (or intermediate outputs) to represent preclinical detectable times, lead time, and age- and ER/HER2-specific stage distribution in screen- versus nonscreen-detected women on the basis of their specific model structure (1, 7, 2330). These model-specific parameters were based on assumptions about combinations of values that reproduced U.S. trends in incidence and breast cancerspecific mortality, including proportions of DCIS that were nonprogressive and would not be detected without screening. Models M and W also assumed some small nonprogressive invasive cancers. The models adopted an ageperiodcohort modeling approach to project incidence rates of breast cancer in the absence of screening (31, 36); model M used 19751979 rates from the Surveillance, Epidemiology, and End Results program. The models assumed 100% adherence to screening and receipt of the most effective treatment to isolate the effect of varying screening strategies. Four models used age-specific sensitivity values for digital mammography that were observed in the Breast Cancer Surveillance Consortium (BCSC) for detection of invasive and DCIS cancers combined (model S uses data for invasive cancers only). Separate values were used for initial and subsequent mammography by screening interval, using standard BCSC definitions: Annual includes data from screens occurring within 9 to 18 months of the prior screen, and biennial includes data on screens within 19 to 30 months (37, 38). Model D used these data as input variables (28), and models GE, S, and W used the data for calibration (24, 25, 27). Models E and M fit estimates from the BCSC and other data (26, 29). Women with ER-positive tumors received 5 years of hormone therapy and an anthracycline-based regimen accompanied by a taxane. Women with ER-negative invasive tumors received anthracycline-based regimens with a taxane. Those with HER2-positive tumors also received trastuzumab. Women with ER-positive DCIS received hormonal therapy (16). Treatment effectiveness was based on clinical trials and was modeled as a reduction in breast cancerspecific mortality risk or increase in the proportion cured compared with ER/HER2-specific survival in the absence of adjuvant treatment (32). Benefits Screening benefits (vs. no screening or incremental to other strategies) included percentage of reduction in breast cancer mortality, breast cancer deaths averted, and life-years and quality-adjusted life-years (QALYs) gained because of averted or delayed breast cancer death. Benefits (and harms) were accumulated from age 40 to 100 years to capture the lifetime effect of screening. We considered preferences, or utilities, to account for morbidity from screening and treatment. A disutility for age- and sex-specific general population health was first applied to quality-adjust the life-years (39). These were further adjusted to account for additional decrements in life-years related to undergoing screening (0.006 for 1 week, or 1 hour), evaluating a positive screen (0.105 for 5 weeks, or 3.7 days), undergoing initial treatment by stage (for the first 2 years after diagnosis), and having distant disease (for the last year of life for all women who die of breast cancer) (Appendix Table 1) (33, 40, 41). Appendix Table 1. Utility Input Parameter Values Use and Harms Use of services focused on the number of mammograms required for the screening strategy. Harms included false-positive mammograms, benign biopsies, and overdiagnosis. Rates of false-positive mammograms were calculated as mammograms read as abnormal or needing further work-up in women without cancer divided by the total number of screening


Journal of the National Cancer Institute | 2014

Benefits, Harms, and Costs for Breast Cancer Screening After US Implementation of Digital Mammography

Natasha K. Stout; Sandra J. Lee; Clyde B. Schechter; Karla Kerlikowske; Oguzhan Alagoz; Donald A. Berry; Diana S. M. Buist; Mucahit Cevik; Gary Chisholm; Harry J. de Koning; Hui Huang; Rebecca A. Hubbard; Diana L. Miglioretti; Mark F. Munsell; Amy Trentham-Dietz; Nicolien T. van Ravesteyn; Anna N. A. Tosteson; Jeanne S. Mandelblatt

BACKGROUND Compared with film, digital mammography has superior sensitivity but lower specificity for women aged 40 to 49 years and women with dense breasts. Digital has replaced film in virtually all US facilities, but overall population health and cost from use of this technology are unclear. METHODS Using five independent models, we compared digital screening strategies starting at age 40 or 50 years applied annually, biennially, or based on density with biennial film screening from ages 50 to 74 years and with no screening. Common data elements included cancer incidence and test performance, both modified by breast density. Lifetime outcomes included mortality, quality-adjusted life-years, and screening and treatment costs. RESULTS For every 1000 women screened biennially from age 50 to 74 years, switching to digital from film yielded a median within-model improvement of 2 life-years, 0.27 additional deaths averted, 220 additional false-positive results, and


Journal of the National Cancer Institute | 2014

Effects of Screening and Systemic Adjuvant Therapy on ER-Specific US Breast Cancer Mortality

Diego F. Munoz; Aimee M. Near; Nicolien T. van Ravesteyn; Sandra J. Lee; Clyde B. Schechter; Oguzhan Alagoz; Donald A. Berry; Elizabeth S. Burnside; Yaojen Chang; Gary Chisholm; Harry J. de Koning; Mehmet Ali Ergun; Eveline A.M. Heijnsdijk; Hui Huang; Natasha K. Stout; Brian L. Sprague; Amy Trentham-Dietz; Jeanne S. Mandelblatt; Sylvia K. Plevritis

0.35 million more in costs. For an individual woman, this translates to a health gain of 0.73 days. Extending biennial digital screening to women ages 40 to 49 years was cost-effective, although results were sensitive to quality-of-life decrements related to screening and false positives. Targeting annual screening by density yielded similar outcomes to targeting by age. Annual screening approaches could increase costs to


Cancer | 2014

Phase angle for prognostication of survival in patients with advanced cancer: Preliminary findings

David Hui; Swati Bansal; Margarita Morgado; Rony Dev; Gary Chisholm; Eduardo Bruera

5.26 million per 1000 women, in part because of higher numbers of screens and false positives, and were not efficient or cost-effective. CONCLUSIONS The transition to digital breast cancer screening in the United States increased total costs for small added health benefits. The value of digital mammography screening among women aged 40 to 49 years depends on womens preferences regarding false positives.


Oncologist | 2014

Clinical Signs of Impending Death in Cancer Patients

David Hui; Renata dos Santos; Gary Chisholm; Swati Bansal; Thiago Buosi Silva; Kelly Kilgore; Camila Souza Crovador; Xiaoying Yu; Michael D. Swartz; Pedro Emilio Perez-Cruz; Aphael de Almeida Leite; Maria Salete de Angelis Nascimento; Suresh K. Reddy; Fabiola de Lourdes Gonõaves de Freitas Seriaco; Sriram Yennu; Carlos Eduardo Paiva; Rony Dev; Stacy Hall; Julieta Fajardo; Eduardo Bruera

BACKGROUND Molecular characterization of breast cancer allows subtype-directed interventions. Estrogen receptor (ER) is the longest-established molecular marker. METHODS We used six established population models with ER-specific input parameters on age-specific incidence, disease natural history, mammography characteristics, and treatment effects to quantify the impact of screening and adjuvant therapy on age-adjusted US breast cancer mortality by ER status from 1975 to 2000. Outcomes included stage-shifts and absolute and relative reductions in mortality; sensitivity analyses evaluated the impact of varying screening frequency or accuracy. RESULTS In the year 2000, actual screening and adjuvant treatment reduced breast cancer mortality by a median of 17 per 100000 women (model range = 13-21) and 5 per 100000 women (model range = 3-6) for ER-positive and ER-negative cases, respectively, relative to no screening and no adjuvant treatment. For ER-positive cases, adjuvant treatment made a higher relative contribution to breast cancer mortality reduction than screening, whereas for ER-negative cases the relative contributions were similar for screening and adjuvant treatment. ER-negative cases were less likely to be screen-detected than ER-positive cases (35.1% vs 51.2%), but when screen-detected yielded a greater survival gain (five-year breast cancer survival = 35.6% vs 30.7%). Screening biennially would have captured a lower proportion of mortality reduction than annual screening for ER-negative vs ER-positive cases (model range = 80.2%-87.8% vs 85.7%-96.5%). CONCLUSION As advances in risk assessment facilitate identification of women with increased risk of ER-negative breast cancer, additional mortality reductions could be realized through more frequent targeted screening, provided these benefits are balanced against screening harms.


Journal of Pain and Symptom Management | 2015

Avoidable and unavoidable visits to the emergency department among patients with advanced cancer receiving outpatient palliative care.

Marvin Omar Delgado-Guay; Yu Jung Kim; Seong Hoon Shin; Gary Chisholm; Janet L. Williams; Julio Allo; Eduardo Bruera

Accurate survival prediction is essential for decision‐making in cancer therapies and care planning. Objective physiologic measures may improve the accuracy of prognostication. In this prospective study, the authors determined the association of phase angle, handgrip strength, and maximal inspiratory pressure with overall survival in patients with advanced cancer.


Cancer | 2015

Bedside clinical signs associated with impending death in patients with advanced cancer: preliminary findings of a prospective, longitudinal cohort study.

David Hui; Renata dos Santos; Gary Chisholm; Swati Bansal; Camila Souza Crovador; Eduardo Bruera

BACKGROUND The physical signs of impending death have not been well characterized in cancer patients. A better understanding of these signs may improve the ability of clinicians to diagnose impending death. We examined the frequency and onset of 10 bedside physical signs and their diagnostic performance for impending death. METHODS We systematically documented 10 physical signs every 12 hours from admission to death or discharge in 357 consecutive patients with advanced cancer admitted to two acute palliative care units. We examined the frequency and median onset of each sign from death backward and calculated their likelihood ratios (LRs) associated with death within 3 days. RESULTS In total, 203 of 357 patients (52 of 151 in the U.S., 151 of 206 in Brazil) died. Decreased level of consciousness, Palliative Performance Scale ≤20%, and dysphagia of liquids appeared at high frequency and >3 days before death and had low specificity (<90%) and positive LR (<5) for impending death. In contrast, apnea periods, Cheyne-Stokes breathing, death rattle, peripheral cyanosis, pulselessness of radial artery, respiration with mandibular movement, and decreased urine output occurred mostly in the last 3 days of life and at lower frequency. Five of these signs had high specificity (>95%) and positive LRs for death within 3 days, including pulselessness of radial artery (positive LR: 15.6; 95% confidence interval [CI]: 13.7-17.4), respiration with mandibular movement (positive LR: 10; 95% CI: 9.1-10.9), decreased urine output (positive LR: 15.2; 95% CI: 13.4-17.1), Cheyne-Stokes breathing (positive LR: 12.4; 95% CI: 10.8-13.9), and death rattle (positive LR: 9; 95% CI: 8.1-9.8). CONCLUSION We identified highly specific physical signs associated with death within 3 days among cancer patients.

Collaboration


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Eduardo Bruera

University of Texas at Austin

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Janet L. Williams

University of Texas MD Anderson Cancer Center

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David Hui

The Chinese University of Hong Kong

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Sriram Yennurajalingam

University of Texas MD Anderson Cancer Center

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David Hui

The Chinese University of Hong Kong

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Kimberson Tanco

University of Texas MD Anderson Cancer Center

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Susan Frisbee-Hume

University of Texas MD Anderson Cancer Center

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Wadih Rhondali

University of Texas MD Anderson Cancer Center

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Julio Allo

University of Texas MD Anderson Cancer Center

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