Organized colorectal cancer screening: the participation rate according to the precariousness

Background

The National Organized Colorectal Cancer Screening Program (DOCCR) was introduced in 2008. The participation rate in France is much lower than the European recommendations (33.5% versus 45%). There are significant disparities across France.

The objective was to assess whether there are disparities in participation rates within the Bouches-du-Rhône(BdR) department and to study the possible correlation of these geographical areas with their level of precariousness.

Methods

Based on data collected by the ARCADES association (management structure in charge of cancer screening in the BdR region), 325,207 people in 2012 and 489,953 in 2017 were invited to participate in the DOCCR. The participation was analysed in two aspects: participation rate (TP) (test carried out) and participation rate of those who took a test or expressed a justified refusal (TPJ) (personal or family history, other test under 2 years old, colonoscopy under 5 years old). An average precariousness rate was also assessed per municipality based on 2012 INSEE data for the age group concerned.

Results

The TP were 18.9% in 2012 and 14.4% in 2017; the TPJ were 22.8% and 16.4% respectively and differs significantly between the municipalities in the department (p < 0.001). The average precariousness rate observed in our population was 12.3 (±8.2). The TPJ is inversely correlated with the precariousness rate: the higher the latter, the lower the participation rate (R=-0.58 in 2012, R=-0.539 in 2017; p < 0.05). The average participation rate whatever the year is lower for municipalities with a precariousness rate below the median (19.2 ± 2 versus 16.9 ± 3.5 for the year 2017).

Conclusions

Participation rates in 2012 and 2017 are lower than the European recommendations. The participation is significantly related to the average rate of precariousness; the most vulnerable participate less well. Specific actions towards the most vulnerable are to be considered in order to improve adherence to the DOCCR.

Key messages

The participation organized colorectal cancer screening program is significantly related to the average rate of precariousness. Specific actions towards the most precarious are to be considered in order to improve adherence to the DOCCR.

HPV self-sampling or the Pap-smear: a randomized study among cervical screening nonattenders from lower socioeconomic groups in France

Today in France, low attendance to cervical screening by Papanicolaou cytology (Pap-smear) is a major contributor to the 3,000 new cervical cancer cases and 1,000 deaths that occur from this disease every year. Nonattenders are mostly from lower socioeconomic groups and testing of self-obtained samples for high-risk Human Papilloma virus (HPV) types has been proposed as a method to increase screening participation in these groups. In 2011, we conducted a randomized study of women aged 35-69 from very low-income populations around Marseille who had not responded to an initial invitation for a free Pap-smear. After randomization, one group received a second invitation for a free Pap-smear and the other group was offered a free self-sampling kit for HPV testing. Participation rates were significantly different between the two groups with only 2.0% of women attending for a Pap-smear while 18.3% of women returned a self-sample for HPV testing (p ≤ 0.001). The detection rate of high-grade lesions (≥CIN2) was 0.2‰ in the Pap-smear group and 1.25‰ in the self-sampling group (p = 0.01). Offering self-sampling increased participation rates while the use of HPV testing increased the detection of cervical lesions (≥CIN2) in comparison to the group of women receiving a second invitation for a Pap-smear. However, low compliance to follow-up in the self-sampling group reduces the effectiveness of this screening approach in nonattenders women and must be carefully managed.

Vaginal self-sampling is an adequate means of screening HR-HPV types in women not participating in regular cervical cancer screening

In France, about 40% of women aged 25-65 years do not participate in regular screening and thus are at high risk (HR) of cervical cancer. Human papillomavirus (HPV) vaginal self-sampling is a valuable alternative in this population. This study aimed to assess the prevalence of HR and LR (low-risk) HPV infection in 3767 women aged >35 years from mid-socioeconomic backgrounds who carried out HPV vaginal self-sampling at home. HPV vaginal self-sampling was better accepted than the Pap-test in women aged 35-69 years who were previously non-responders to individual invitation. From the 933 self-collected swabs studied (24.7%), 62 were HPV-infected (6.6%), and 73 HPV types were found. HPV 16 was the most frequently found (43.5%), followed by 53 (23.2%), 18 (12.3%), 66 (12.3%), 31 (6.8%), 33 (5.4%) and 58 (2.7%). Ten women (16.2%) were infected by multiple HR-HPV types. Median HPV 16 load was 104.000 copies/10(6) cells and median HPV 18 load was 833 copies/10(6) cells. Six women (9.3%) harboured LR-HPV types. The 12-month follow-up of 43 HR-HPV positive women (69.3%) revealed CIN2-3 lesions in three women (6.9%), all HPV 16 infected, and harbouring an HPV 16 load >5 log(10) copies/10(6) cells. Women harbouring HR-HPV types other than HPV 16/18 were older than women harbouring HPV 16/18 types (55 years vs. 46.9 years, p 0.0008). The high frequency of HR-HPV types in women >50 years deserves further investigation to elucidate the mechanism involved (re-infection or reactivation).

[Digital mammography: performance evaluation parameters and available systems in France]

The purpose of this article is to review the features of digital mammography systems available in France. This article includes three parts: definition of the different components of a digital mammography system, description of different performance evaluation parameters, and review of systems currently available in France. Data from the literature as well as questionnaires from different manufacturers were used. The following vendors agreed to participate: Agfa, Fujifilm, GE Healthcare, Hologic-Lorad, IMS, Kodak, Konica Minolta, Philips, Planmed, Sectra, Siemens. For each vendor, the type of detector, type of available mammographic units and workstation, optional features (CAD), archival and printing possibilities (when vendors specifically offer dedicated solutions).

[Digital mammography and computer assisted diagnosis]

Until recently, the film has remained the only medium of information in mammography. The film is used to record, to exploit, to store and to transmit the image. Computerization of images allows to dissociate and to optimize these different functions. Among classical factors of image quality (spatial resolution, contrast, noise), new factors should be added like the detective quantum efficiency and the conversion factor. Radioluminescent screens, then digital sensors for breast stereotactic imaging have been marketed. Manufacturers are now testing full field digital mammographs. Digital imaging allows many applications (computed-aided diagnostic, 3D imaging.) and permits the easy transfer of images for diagnosis and teaching. Three parts are presented in this chapter. The first one describes the different imaging modalities and gives a reminder of the different elements related to image quality. The second one is related to the practical aspects of full field mammography, the reading of mammograms on a review station, ergonomy in full field mammography and to possible changes for screening mammography. The third part is devoted to computed aided diagnosis and its possible application in screening.

The internal phosphodiesterase RegA is essential for the suppression of lateral pseudopods during Dictyostelium chemotaxis

Dictyostelium strains in which the gene encoding the cytoplasmic cAMP phosphodiesterase RegA is inactivated form small aggregates. This defect was corrected by introducing copies of the wild-type regA gene, indicating that the defect was solely the consequence of the loss of the phosphodiesterase. Using a computer-assisted motion analysis system, regA(-) mutant cells were found to show little sense of direction during aggregation. When labeled wild-type cells were followed in a field of aggregating regA(-) cells, they also failed to move in an orderly direction, indicating that signaling was impaired in mutant cell cultures. However, when labeled regA(-) cells were followed in a field of aggregating wild-type cells, they again failed to move in an orderly manner, primarily in the deduced fronts of waves, indicating that the chemotactic response was also impaired. Since wild-type cells must assess both the increasing spatial gradient and the increasing temporal gradient of cAMP in the front of a natural wave, the behavior of regA(-) cells was motion analyzed first in simulated temporal waves in the absence of spatial gradients and then was analyzed in spatial gradients in the absence of temporal waves. Our results demonstrate that RegA is involved neither in assessing the direction of a spatial gradient of cAMP nor in distinguishing between increasing and decreasing temporal gradients of cAMP. However, RegA is essential for specifically suppressing lateral pseudopod formation during the response to an increasing temporal gradient of cAMP, a necessary component of natural chemotaxis. We discuss the possibility that RegA functions in a network that regulates myosin phosphorylation by controlling internal cAMP levels, and, in support of that hypothesis, we demonstrate that myosin II does not localize in a normal manner to the cortex of regA(-) cells in an increasing temporal gradient of cAMP.

Hormone replacement therapy and screening mammography: analysis of the results in the Bouches du Rhône programme

OBJECTIVE

To evaluate the effectiveness of a mass screening programme for breast cancer in a French population where hormone replacement therapy (HRT) is common and where mammography is prescribed outside the programme for asymptomatic women.

METHODS

From 1993 to 1996 inclusive, 41,062 women underwent a first test and 48,275 a second or third test in the Bouches du Rhône programme. Their HRT status was ascertained at the time of the test. False positive and false negative tests were identified at one year follow up. The incidence of interval cancers was estimated up to three years after the screening test.

RESULTS

The odds of being detected at screening rather than as an interval cancer within one year of the test was five times greater among non-users of HRT than among users (odds ratio (OR) 5.14 (confidence interval 2.5 to 11.8)). This high reduction in sensitivity among users (71% v 92%) was associated with a very small reduction in specificity at the incident screen only. The incidence of interval cancers among HRT users was 3.5 times that of non-users within the first year after the test and 1.7 times during the following two years.

CONCLUSIONS

When the early results of a programme have been used to measure its effectiveness they should be reassessed in populations where HRT is in widespread use. As interval cancers had better prognostic factors in HRT users than in non-users, the efficacy of a screening programme in such populations should be the subject of further studies.

Kinetic analysis of the hydrodynamic transition accompanying protein folding using size exclusion chromatography. 1. Denaturant dependent baseline changes

Size exclusion profiles of proteins with persistent conformations exhibit broad asymmetric peaks whose shape and elution times are dependent on denaturant concentration. The collective elution profiles were precisely simulated by an apparent binding model that treats the denaturant dependence in terms of an apparent matrix binding. The model requires three experimentally measurable parameters: the elution time for the unbound protein, an apparent association equilibrium constant for binding, and an apparent exchange time for binding. The denaturant dependence for each of these parameters is related to the accessible surface area of the protein.

A kinetic study of the folding of staphylococcal nuclease using size-exclusion chromatography

The kinetics of the hydrodynamic volume change accompanying the reversible unfolding of staphylococcal nuclease have been observed by size-exclusion chromatography at 4 degrees C and pH 7.0 using the denaturant guanidine hydrochloride. The observed chromatographic profiles have been simulated by a six-component unfolding/refolding mechanism using a consistent set of equilibrium and kinetic parameters. The native protein is an equilibrium mixture of the cis and trans isomers of the peptide bond preceding proline-117. The native conformation containing the cis isomer dominates the equilibrium mixture, is more stable, and unfolds more slowly at its transition midpoint. The denatured protein is an equilibrium mixture of at least four components, the cis/trans isomers of proline-117 and one of the five remaining prolines. The dominant refolding pathway is initiated from the denatured component containing the trans isomer of proline-117. The six-component mechanism is consistent with tryptophan fluorescence kinetic measurements of the wild-type protein and with chromatographic measurements of a mutant P117G protein.