Modelling the effect of breast cancer screening on related mortality using French data.

INTRODUCTION: This study aimed at modelling the effect of organized breast cancer screening on mortality in France. It combined results from a Markov model for breast cancer progression, to predict number of cases by node status, and from relative survival analyses, to predict deaths. The method estimated the relative risk of mortality at 8 years, in women aged 50-69, between a population screened every two years and a reference population. METHODS: Analyses concerned cases diagnosed between 1990 and 1996, with a follow-up up to 2004 for the vital status. Markov models analysed data from 3 screening programs (300,000 mammographies) and took into account opportunistic screening among participants to avoid bias in parameter's estimates. We used survival data from cancers in the general population (n=918, 7 cancer registries) and from screened cancers (n=565, 3 cancer registries), after excluding a subgroup of screened cases with a particularly high survival. Sensitivity analyses were performed. RESULTS: Markov model main analysis lacked of fit in two out of three districts. Fit was improved in stratified analyses by age or district, though some lack of fit persisted in two districts. Assuming 10% or 20% overdiagnosed screened cancers, mortality reduction was estimated as 23% (95% CI: 4, 38%) and 19% (CI: -3, 35%) respectively. Results were highly sensitive to the exclusion in the screened cancers survival analysis. Conversely, RR estimates varied moderately according to the Markov model parameters used (stratified by age or district). CONCLUSION: The study aimed at estimating the effect of screening in a screened population compared to an unscreened control group. Such a control group does not exist in France, and we used a general population contaminated by opportunistic screening to provide a conservative estimate. Conservative choices were systematically adopted to avoid favourable estimates. A selection bias might however affect the estimates, though it should be moderate because extreme social classes are under-represented among participants. This modelling provided broad estimates for the effect of organized biennial screening in France in the early nineteen-nineties. Results will be strengthened with longer follow-up.

Multi-state Markov models in cancer screening evaluation: a brief review and case study.

This work presents a brief overview of Markov models in cancer screening evaluation and focuses on two specific models. A three-state model was first proposed to estimate jointly the sensitivity of the screening procedure and the average duration in the preclinical phase, i.e. the period when the cancer is asymptomatic but detectable by screening. A five-state model, incorporating lymph node involvement as a prognostic factor, was later proposed combined with a survival analysis to predict the mortality reduction associated with screening. The strengths and limitations of these two models are illustrated using data from French breast cancer service screening programmes. The three-state model is a useful frame but parameter estimates should be interpreted with caution. They are highly correlated and depend heavily on the parametric assumptions of the model. Our results pointed out a serious limitation to the five-state model, due to implicit assumptions which are not always verified. Although it may still be useful, there is a need for more flexible models. Over-diagnosis is an important issue for both models and induces bias in parameter estimates. It can be addressed by adding a non-progressive state, but this may provide an uncertain estimation of over-diagnosis. When the primary goal is to avoid bias, rather than to estimate over-diagnosis, it may be more appropriate to correct for over-diagnosis assuming different levels in a sensitivity analysis. This would be particularly relevant in a perspective of mortality reduction estimation.

[Reattendance of women for breast cancer screening programs. A review]. / Participation secondaire des femmes au dépistage organisé du cancer du sein Revue de la littérature.

BACKGROUND: In France, breast cancer is the most frequently occurring cancer and the leading cause of cancer deaths in women. Breast cancer screening has been shown to reduce breast cancer mortality by 30% provided attendance rate is 70% and re-screening interval is two to three years. Maintaining a high rate of reattendance is also important. The decline with time of completion rates of re-screening will lessen the benefits of a breast cancer screening program. METHODS: A review of published studies examining factors associated with attendance and reattendance to breast cancer screening. RESULTS: Positive views about initial screening are determining factors in reattendance: mammography should not be painful and embarrassing, appointments should be punctual and clinic staff courteous and supportive. Psychological factors influencing attendance also influence reattendance as does intention to participate, a major predictor of repeat participation and as do perceived susceptibility of breast cancer, perceived benefits of mammography, absence of emotional barriers. These factors can be modified by experience of previous screening. Other predicting factors of attendance continue to influence reattendance: practice of other preventive health behaviors, outside support from physicians, knowledge of breast cancer and screening. CONCLUSION: A better understanding of factors influencing attendance is necessary to increase the impact of breast cancer screening. Field studies are necessary to support the elaboration of publicity campaigns aimed at increasing participation.

[Non metastatic breast cancer surgery in the Rhône department between 1988 and 1994]. / Traitement chirurgical du cancer du sein de stade M0 entre 1988 et 1994 dans le département du Rhône.

BACKGROUND: From the results obtained in the breast cancer register, this report describes the usual surgical practice of breast cancer in the Rhône department (France). METHODS: This study concerned 4,028 cases of non-metastatic breast cancer diagnosed during the period 1988-1994. Three periods were determined (1988-89, 1990-92, 1993-94). Univariate analysis described the relation between the type of surgical practice and the explanatory factors. Logistic regression analysis was used to search for changes in surgical practice during the three periods. RESULTS: The proportion of conservative breast surgery rose from 53% in 1988 to 64.5% in 1994. Taking the period 1988-89 as the reference period, the adjusted odds ratio of conservative surgery during the period 1990-92 was 1.4 [1.1-1.7]. During the period 1993-94, this adjusted odds ratio was 1.9 [1.6-2.3]. Finally we observed that conservative surgery was less frequent in patients 70 years of age or older. CONCLUSION: Conservative breast surgery increased significantly during the defined period. This observation can be explain by two events. First there was a significant increase of small breast cancer (< 20 mm) among women aged 50 to 69 who benefited from the systematic screening breast cancer since 1988. Secondly a significant "period effect" was observed. This "period effect" proves a modification of surgical practice after adjustment for cancer characteristics.

Psychosocial profile of women seeking breast reconstruction.

As opposed to studies focused on the role of reconstruction in the rehabilitation of cancer patients, the aim of this study is to define what kind of women undergo post-mastectomy reconstruction. The social, cultural and psychological variables influencing women in this choice were assessed using a questionnaire administered to 45 women who had breast reconstruction and 51 who did not. An univariate analysis shows significant differences between the two groups regarding age, education, socioeconomic status, leisure activities, sexual intercourse, information about breast reconstruction and fear of recurrence. These results show that social status is a deciding factor in a woman's access to information about reconstruction. If every women undergoing mastectomy is to be given the opportunity of plastic surgery, we think that information must be adapted to psychosocial profile.

[Systematic screening for breast cancer in Rhone]. / Dépistage systématique du cancer du sein dans le Rhône.

OBJECTIVE: As systematic breast cancer screening is progressively being implemented on a nationwide basis in France, we would like to describe the first population based breast cancer screening programme that started in the Rhône departement in 1987. METHOD: All women aged 50 to 70 living in the Rhône are invited for single-view mammography every three years. Mammograms are done using the existing facilities by one of the 120 radiologists of the department qualified for screening for the program. All screens undergo double reading organized by l'Association des Radiologues du Rhône pour le Dépistage des Maladies du Sein (ARRADEMAS). The result of the test is given to the woman and her primary care doctor or gynaecologist who initiates the assessment of screen detected abnormalities. Evaluation and monitoring of the programme are based on the combined data of the screening information center and the local breast cancer registry. RESULTS: Available data, seven years after the beginning of the programme, already show that its main short term measures are satisfactory: recent data show an acceptance rate of 50% and a recall rate of about 8%. At the prevalent screen, biopsy rate is 1.3% and detection rate 6 per 1000. Moreover, the programme information system has achieved its target in enabling us to collect data on all breast cancer cases occurring not only in women screened but in the whole population invited to screening.

[Incidence of breast cancer in the Rhône area--influence of urban or rural character of the communities and of the population density]. / Incidence du cancer du sein dans le département du Rhône--influence du caractère urbain ou rural des communes et de la densité de population.

The specific breast cancer register created in 1988 in the Rhône department demonstrated a high incidence of breast cancer among the women who live in this department (world standardised incidence rate = 79.4). This report presents the results according to two geographical aspects: the urban or rural structure of the area of residence and the population density. These analysis demonstrated an association between the high incidence of female breast cancer and the urban character of the department. However the results of incidence in the urban and rural zone were heterogeneous. The high incidence of breast cancer in the North of the department corresponding to a vineyard region confirmed this association.

[Spontaneous regression of flat condylomata of the cervix]. / Régression spontanée des condylomes plan du col utérin.

In this study 146 patients with a human papilloma virus infection of the cervix detected on cervical smear. This infection was at the worst associated with CIN 1 or CIN 2. No treatment was carried out on these patients except for advising the use of condoms. Among the 123 women whose diagnosis was CIN 1, 65.2% of them had a negative smear within 18 months. This somewhat high rate of spontaneous regression was found in out patients who were not selected. They are near the results published by Brown in a similar study. The statistics drawn from hospital patients give lower regression rates; but these patients were selected by their doctors because they did not show regression on subsequent smears. It is therefore recommended that these patients should be assessed colposcopically and there should be a wait of 6-12 months before treating patients with CIN 1.