1.Quantifying the duration of the preclinical detectable phase in cancer screening: a systematic review
Sandra M. E. GEURTS ; Anne M. W. M. AARTS ; André L. M. VERBEEK ; Tony H. H. CHEN ; Mireille J. M. BROEDERS ; Stephen W. DUFFY
Epidemiology and Health 2022;44(1):e2022008-
OBJECTIVES:
The aim of this study was to provide an overview of published mathematical estimation approaches to quantify the duration of the preclinical detectable phase (PCDP) using data from cancer screening programs.
METHODS:
A systematic search of PubMed and Embase was conducted for original studies presenting mathematical approaches using screening data. The studies were categorized by mathematical approach, data source, and assumptions made. Furthermore, estimates of the duration of the PCDP of breast and colorectal cancer were reported per study population.
RESULTS:
From 689 publications, 34 estimation methods were included. Five distinct types of mathematical estimation approaches were identified: prevalence-to-incidence ratio (n=8), maximum likelihood estimation (n=16), expectation-maximization algorithm (n=1), regression of observed on expected (n=6) and Bayesian Markov-chain Monte Carlo estimation (n=5). Fourteen studies used data from both screened and unscreened populations, whereas 19 studies included only information from a screened population. Estimates of the duration of the PCDP varied between 2 years and 7 years for breast cancer in the Health Insurance Plan study (annual mammography and clinical breast examinations in women aged 40-64 years) and 2 years and 5 years for colorectal cancer in the Calvados study (a guaiac fecal occult blood test in men and women aged 45-74 years).
CONCLUSIONS
Different types of mathematical approaches lead to different estimates of the PCDP duration. We advise researchers to use the method that matches the data available, and to use multiple methods for estimation when possible, since no method is perfect.
2.Limiting the use of primary endocrine therapy in elderly women with breast cancer.
Shaun W Y CHAN ; Patrick M Y CHAN ; Melanie D W SEAH ; Juliana J C CHEN ; Ern Yu TAN
Annals of the Academy of Medicine, Singapore 2014;43(9):469-472
Primary endocrine therapy (PET) is often included as a treatment option in elderly women with operable breast cancer. Elderly women tend to have pre-existing comorbidities and are often reluctant to undergo surgery. The benefit of surgery needs to be weighed against a relatively higher potential for operative morbidity and mortality, and a limited life expectancy. But while PET can provide relatively good locoregional control, it is not curative in nature and the possibility of local complications and metastasis remains. We retrospectively reviewed the outcome of PET in a series of 19 elderly women, older than 70 years of age, who had presented with operable non-metastatic breast cancer. Only about a third of these women were deemed medically unfit for surgery; the rest had declined surgery. Compliance was an issue, with almost half of these patients defaulting treatment and follow-up. Local control was achieved in most patients, but disease progression did occur in 5 patients. Three of these patients received additional treatment; which included surgery in 1 patient. PET should therefore not be considered an equivalent alternative to surgery in elderly women who were fi t to undergo surgery. However, having observed that only 1 of the 6 deaths in our study was related to breast cancer, PET does have a role in women whose life expectancy is more likely to be limited by coexisting morbidities than the breast cancer itself.
Aged
;
Aged, 80 and over
;
Antineoplastic Agents, Hormonal
;
therapeutic use
;
Breast Neoplasms
;
drug therapy
;
Drug Therapy
;
utilization
;
Female
;
Humans
;
Retrospective Studies
;
Tamoxifen
;
therapeutic use
3.Surveillance of Aedes mosquitoes in a university campus in Kuala Lumpur, Malaysia.
O Wan Norafikah ; C D Chen ; H N Soh ; H L Lee ; W A Nazni ; M Sofian Azirun
Tropical biomedicine 2009;26(2):206-15
Ovitrap surveillance was initiated for eight continuous weeks to determine the distribution and abundance of Aedes sp. mosquitoes in the University of Malaya campus, Kuala Lumpur, and the impact of meteorological conditions on the Aedes populations. Two study areas within the campus were selected: Varsity Lake and Seventh Residential College. The abundance of Aedes populations in Varsity Lake was indicated by ovitrap index (OI) which ranged from 60.00% - 90.00%. The mean number of larvae per ovitrap of Aedes albopictus in Varsity Lake ranged from 11.23 +/- 2.42 - 43.80 +/- 6.22. On the other hand, the outdoor OI for Seventh Residential College ranged from 73.33% - 93.33%, respectively, while the mean number larvae per ovitrap for this area ranged from 19.33 +/- 4.55 - 35.27 +/- 5.46, respectively. In addition, the indoor OI of Seventh Residential College ranged from 0.00% - 30.00%, while the mean number of larvae per ovitrap for Ae. albopictus ranged from 0 - 5.90 +/- 3.55. There was no significant difference (p > 0.05) of Ae. albopictus population between Varsity Lake and Seventh Residential College. The studies showed a correlation between OI and mean number of larvae per ovitrap for outdoor Ae. albopictus populations in Varsity Lake and Seventh Residential College (r = 0.794). There was also a correlation between the mean larvae number per ovitrap of Ae. albopictus obtained from eight weeks indoor ovitrap surveillance in Seventh Residential College with rainfall (r = 0.584). However, there was no correlation between the mean larvae number per ovitrap of Ae. albopictus in both study areas with temperature and relative humidity. Aedes aegypti mosquitoes were found neither indoor nor outdoor in both study areas. This study indicated that the principal dengue vector in the university campus was most likely Ae. albopictus.
College
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Seventh
;
Lake
;
Aedes
;
seconds
4.COGNITIVE AND MOTOR OUTCOME AFTER LONG-TERM GLOBUS PALLIDUS EXTERNA DEEP BRAIN STIMULATION TO TRANSGENIC HUNTINGTON'S DISEASE RAT
Chunyan CAO ; Yasin Temel ; Arjan Blokland ; Veerle Visser-Vandewalle ; Harry W. M. Steinbusch ; Shengdi CHEN ; Zhenguo LIU
Chinese Journal of Neuroanatomy 2006;22(3):275-280
In this study, we treated transgenic Huntington's disease (tgHD) model rat with deep brain stimulation (DBS) and evaluated the cognitive and motor outcome. The results showed that the surgery of implanting electrode improved cognition, increased correct rate and decreased response bias in choice reaction time (CRT) task, with similar extent on various genotypes. After long-term DBS to globus pallidus externa( GPe), correct rate was enhanced. The enhancement was genotype related. Additionally, the motor time and reaction time in CRT task reflecting the movement initiation kept the same value, but the chorea-form movement of homozygous rats was rectified prominently after the treatment of DBS. The present results demonstrated that the operation of long-term DBS to globus pallidus externa can improve the cognition and motor outcome of tgHD rats, which implied DBS operation might shed light on HD patients in the future.
5.Post community hospital discharge rehabilitation attendance: Self-perceived barriers and participation over time.
Abel W L CHEN ; Yan Tong KOH ; Sean W M LEONG ; Louisa W Y NG ; Patricia S Y LEE ; Gerald C H KOH
Annals of the Academy of Medicine, Singapore 2014;43(3):136-144
INTRODUCTIONThis study aimed to examine the attendance rates of post-discharge supervised rehabilitation as recommended by the multidisciplinary team at discharge among subacutely disabled adults and the barriers preventing adherence.
MATERIALS AND METHODSPatients were from a community hospital, aged 40 years or older. They had been assessed by a multidisciplinary team to benefit from rehabilitation after discharge, were mentally competent and communicative. We used a sequential qualitative-quantitative mixed methods study design. In the initial qualitative phase, we studied the patient-perceived barriers to adherence to rehabilitation using semi-structured interviews. Emerging themes were then analysed and used to develop a questionnaire to measure the extent of these barriers. In the subsequent quantitative phase, the questionnaire was used with telephone follow-up at 3, 6, 9 and 12 months after discharge.
RESULTSQualitative phase interviews (n = 41) revealed specific perceived financial, social, physical and health barriers. At the start of the quantitative phase (n = 70), 87.1% of the patients viewed rehabilitation as beneficial, but overall longitudinal attendance rate fell from 100% as inpatient to 20.3% at 3 months, 9.8% at 6 months, 6.3% at 9 months and 4.3% at 12 months. The prevalence of physical and social barriers were high initially but decreased with time. In contrast, the prevalence of financial and perceptual barriers increased with time.
CONCLUSIONAttendance of post-hospitalisation rehabilitation in Singapore is low. Self-perceived barriers to post-discharge rehabilitation attendance were functional, social, financial and perceptual, and their prevalence varied with time.
Adult ; Aged ; Aged, 80 and over ; Female ; Health Services Accessibility ; Hospitals, Community ; Humans ; Male ; Middle Aged ; Patient Compliance ; Patient Discharge ; Qualitative Research ; Rehabilitation ; Self Concept ; Surveys and Questionnaires ; Time Factors
6.Progress of research on the association between air pollution and prevalence of major cancers.
Z X YANG ; H M ZENG ; R S ZHENG ; C F XIA ; S W ZHANG ; W Q CHEN
Chinese Journal of Epidemiology 2018;39(4):532-535
Being an undisputed risk factor of cancer, air pollution is posing a huge threat to the health on human beings. In this article, we introduced the composition of air pollution, and the standards on air quality which was set by both World Health Organization and the Chinese government. We also summarized the most recent research findings on the association between air pollution and the risk of lung, breast, bladder and other major cancers.
Air Pollutants/toxicity*
;
Air Pollution/adverse effects*
;
Humans
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Neoplasms/epidemiology*
;
Prevalence
;
Research/trends*
;
Risk Factors
7.Prophylactic Dual Catheter Technique to Prevent Side Branch Snowplowing Complications during Angioplasty and Stenting.
Leonard LL YEO ; W M WU ; Y L CHEN ; C H YEH ; H F WONG
Journal of Cerebrovascular and Endovascular Neurosurgery 2017;19(1):12-18
OBJECTIVE: Angioplasty and Stenting of intracranial atherosclerotic lesions have a higher complication rate and a large proportion of this is attributable to side branch arterial occlusion from forceful displacement of the atheroma into the ostia or snowplowing effect. This can result in severe disabilities when it result in small infarcts involving eloquent areas in the posterior circulation or the motor tracts. MATERIALS AND METHODS: We present a series of 6 cases utilizing a new dual catheter technique for maintaining the patency of at-risk vessels during angioplasty and stenting. There are several methods previously described to help reduce the incidence of stroke but because they do not have a physical presence in the ostia to protect it, they are unable to guarantee the patency of the vessel. RESULTS: All 6 patients underwent angioplasty and stenting with the technique. The patients were assessed for complications with post-procedure magnetic resonance imaging and no complications were found. CONCLUSION: In this preliminary series, the dual catheter technique appears to safe and effective in preventing occlusion of the adjacent branch arteries. This technique may facilitate the use of the Wingspan stent in the treatment of intracranial atherosclerotic stenotic segments by reducing the risk of peri-procedural stroke.
Angioplasty*
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Arteries
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Catheters*
;
Humans
;
Incidence
;
Magnetic Resonance Imaging
;
Plaque, Atherosclerotic
;
Stents*
;
Stroke
8.Optical imaging of nociception in primary somatosensory cortex of non-human primates.
Li-Min CHEN ; Robert M FRIEDMAN ; Anna W ROE
Acta Physiologica Sinica 2008;60(5):664-668
While the activation of primary somatosensory (SI) cortex during pain perception is consistently reported in functional imaging studies on normal subjects and chronic pain patients, the specific roles of SI, particularly the subregions within SI, in the processing of sensory aspects of pain are still largely unknown. Using optical imaging of intrinsic signal (OIS) and single unit electrophysiology, we studied cortical activation patterns within SI cortex (among Brodmann areas 3a, 3b and 1) and signal amplitude changes to various intensities of non-nociceptive, thermal nociceptive and mechanical nociceptive stimulation of individual distal finerpads in anesthetized squirrel monkeys. We have demonstrated that areas 3a and 1 are preferentially involved in the processing of nociceptive information while areas 3b and 1 are preferentially activated in the processing of non-nociceptive (touch) information. Nociceptive activations of individual fingerpad were organized topographically suggesting that nociceptive topographic map exits in areas 3a and 1. Signal amplitude was enhanced to increasing intensity of mechanical nociceptive stimuli in areas 3a, 3b and 1. Within area 1, nociceptive response co-localizes with the non-nociceptive response. Therefore, we hypothesize that nocicepitve information is area-specifically represented within SI cortex, in which nociceptive inputs are preferentially represented in areas 3a and 1 while non-nociceptive inputs are preferentially represented in areas 3b and 1.
Animals
;
Brain Mapping
;
Nociception
;
physiology
;
Pain
;
Saimiri
;
Somatosensory Cortex
;
physiology
;
Touch
9.Stratified sampling survey of major human parasitic diseases in Henan province.
B L XU ; H W ZHANG ; Y DENG ; Z L CHEN ; W Q CHEN ; D L LU ; Y L ZHANG ; Y L ZHAO ; X M LIN ; Q HUANG ; C Y YANG ; Y LIU ; R M ZHOU ; P LI ; J S CHEN ; L J HE ; D QIAN
Chinese Journal of Epidemiology 2018;39(3):322-328
Objective: To understand the prevalence of major human parasitic diseases and related factors in Henan province. Methods: This stratified sampling survey was carried out according to the requirement of national survey protocol of major human parasitic diseases, 2014-2015. The prevalence of soil-transmitted helminths infection, taeniasis and intestinal protozoiasis were surveyed in 104 sites selected from 35 counties (districts) and the prevalence of clonorchiasis was surveyed in 62 sites selected from 37 townships. In each survey spot, 250 persons were surveyed. A total of 26 866 persons and 15 893 persons were surveyed. Modified Kato-Katz thick smear was used to detect the eggs of intestinal helminthes. Tube fecal culture was used to identify the species of hookworm. The Enterobius eggs were detected in children aged 3 to 6 years by using adhesive tape. The cyst and trophozoite of intestinal protozoa were examined with physiological saline direct smear method and iodine stain method. Results: The overall infestation rate of intestinal parasites was2.02% in Henan, and the worm infection rate was higher than protozoa infection rate. Fourteen kinds of intestinal parasites were found, including nematode (5 species), trematode (2 species), and protozoan (7 species). The infection rate of Enterobius vermicularis was highest, and Qinba Mountain ecological area had the highest infestation rate of intestinal parasites in 4 ecological areas of Henan. There was no significant difference in intestinal parasite infection rate between males and females (χ(2)=3.630, P=0.057), and the differences in intestinal parasite infection rate among different age groups had significance (χ(2)=124.783, P=0.000 1). The infection rate reached the peak in age group ≤9 years and the major parasite was Enterobius vermicularis. Furthermore the overall human infection rate of parasite showed a downward trend with the increase of educational level of the people (χ(2)=70.969, P=0.000 1), the differences had significance (χ(2)=120.118, P=0.000 1). For different populations, the infection rate of intestinal parasites was highest among preschool children. The infection of intestinal helminth was mainly mild, only 2 severe cases were detected. The infection rate of Clonorchis sinensis in urban residents was only 0.006%. Logistic regression analysis showed that being preschool children (χ(2)=15.765, P=0.000 1) and drinking well water (χ(2)=45.589, P=0.000 1) were the risk factors for intestinal parasite infection, and annual income per capita of farmers was the protective factor against intestinal parasite infection. The infection rates of protozoa and intestinal parasites decreased sharply compared with the results of previous two surveys, and the rate of intestinal helminth infection also dropped sharply compared with the second survey. The numbers of protozoa, helminth and intestinal parasites detected in this survey were all less than the numbers found in the previous two surveys. Conclusions: Compared the results of three surveys in Henan, the infection rate of protozoa and intestinal parasites showed a downward trend. The prevention and treatment of Enterobius vermicularis infection in children should be the key point of parasitic disease control in the future.
Animals
;
Child
;
Child, Preschool
;
Clonorchiasis/epidemiology*
;
Farmers
;
Feces/parasitology*
;
Female
;
Helminthiasis/epidemiology*
;
Helminths
;
Humans
;
Intestinal Diseases, Parasitic/parasitology*
;
Male
;
Prevalence
;
Protective Factors
;
Risk Factors
;
Rural Population
;
Soil Microbiology
;
Surveys and Questionnaires
;
Taeniasis/epidemiology*
;
Trematode Infections/parasitology*
;
Urban Population
;
Water Wells
10.Continuous peripheral nerve blocks compared to thoracic epidurals or multimodal analgesia for midline laparotomy: a systematic review and meta-analysis
Jonathan G. BAILEY ; Catherine W MORGAN ; Russell CHRISTIE ; Janny Xue Chen KE ; M. Kwesi KWOFIE ; Vishal UPPAL
Korean Journal of Anesthesiology 2021;74(5):394-408
Background:
Continuous peripheral nerve blocks (CPNBs) have been investigated to control pain for abdominal surgery via midline laparotomy while avoiding the adverse events of opioid or epidural analgesia. The review compiles the evidence comparing CPNBs to multimodal and epidural analgesia.
Methods:
We conducted a systematic review using broad search terms in MEDLINE, EMBASE, Cochrane. Primary outcomes were pain scores and cumulative opioid consumption at 48 hours. Secondary outcomes were length of stay and postoperative nausea and vomiting (PONV). We rated the quality of the evidence using Cochrane and GRADE recommendations. The results were synthesized by meta-analysis using Revman.
Results:
Our final selection included 26 studies (1,646 patients). There was no statistically significant difference in pain control comparing CPNBs to either multimodal or epidural analgesia (low quality evidence). Less opioids were consumed when receiving epidural analgesia than CPNBs (mean difference [MD]: –16.13, 95% CI [–32.36, 0.10]), low quality evidence) and less when receiving CPNBs than multimodal analgesia (MD: –31.52, 95% CI [–42.81, –20.22], low quality evidence). The length of hospital stay was shorter when receiving epidural analgesia than CPNBs (MD: -0.78 days, 95% CI [-1.29, -0.27], low quality evidence) and shorter when receiving CPNBs than multimodal analgesia (MD: -1.41 days, 95% CI [-2.45, -0.36], low quality evidence). There was no statistically significant difference in PONV comparing CPNBs to multimodal (high quality evidence) or epidural analgesia (moderate quality evidence).
Conclusion
CPNBs should be considered a viable alternative to epidural analgesia when contraindications to epidural placement exist for patients undergoing midline laparotomies.