[Incidence and prognostic factors of breast cancer diagnosed within and outside of the organised screening program in the department of Loire-Atlantique (1991-2002)]. / Incidence et facteurs pronostiques des cancers du sein découverts au cours et en dehors du programme de dépistage organisé en Loire-Atlantique (1991-2002).

BACKGROUND: This study aimed to evaluate the impact of breast cancer mass screening, which began in 1996 in Loire-Atlantique (France), on the evolution of incidence and characteristics of breast cancer between 1991 and 2002. METHODS: The cancer Registry of Loire-Atlantique recorded characteristics of 9263 incident breast cancers diagnosed between 1991 and 2002. The level of participation to the organised screening program was 48%, thus the screening management structure allowed characterizing 736 cancers discovered by organised screening between 1997 and 2002. RESULTS: The 1991-2002 period was marked by a strong increase of in situ cancer proportion (from 5% at the beginning to 10% at the end of the period) and of standardised incidence rates (from 77 to 103/10(5) and from 4 to 13/10(5) for invasive and in situ cancers, respectively). Incidence was already rising before the beginning of the organised screening program in 1996. During the 1997-2002 period, in spite of steady rates for cancers detected by organised screening, incidence of cancers detected outside organised screening went on increasing. Cancers detected by organised screening were more often of smaller size (33% versus 22% smaller than 10mm) and without lymph node invasion (70% versus 62%). CONCLUSION: A strong increase of breast cancer incidence was observed in Loire-Atlantique, particularly in the organised screening age groups. The persistent increase of in situ cancers for women younger than 50 years old unconcerned by the organised screening program, and also for women of 50-74 years old detected outside the organised screening program suggested a parallel contribution of individual screening. These preliminary results confirm better prognostic factors for cancer detected by organised screening than for others.

[Architectural distortion and diagnostic difficulties]. / Distorsions architecturales et difficultés diagnostiques.

Identification of architectural distortion requires a good practice of mammography. Prevalence is estimated at 6% of detected abnormalities in screening programs. Under this denomination are gathered focal architectural distortion with predictive positive value (PPV) of 10% and stellate images without central densification, which are more suspicious (PPV 50%). In order to establish a diagnosis, false images must be eliminated by other views. Minimal architectural distortion have to be investigated by other techniques (sonography, MRI percutaneous biopsy) in order to define the best strategy for further management. Stellate images suggestive of radial scars must be surgically removed. The relationships between radial scars and tubular carcinoma are discussed. A particular attention is required for post traumatic or post surgical scars if it exist a high risk of local recurrence or controlateral carcinoma specially after conservative or oncoplastic surgery.

Recent trends in breast cancer incidence rates in the Loire-Atlantique, France: a decline since 2003.

BACKGROUND: A recent decline in breast cancer incidence rates has been reported in the United States and in Europe. This decrease has been partly attributed to the reduced use of hormone replacement therapy (HRT). No study in Europe has detailed recent breast cancer incidence trends both by hormonal receptor status and mode of detection at an individual level. METHODS: We examined trends in breast cancer incidence rates in the French administrative area of Loire-Atlantique between 1991 and 2007, by age, mode of detection, histological subtype, estrogen/progesterone receptor (ER/PR) status and grade. Annual age-standardized breast cancer incidence rates were estimated using the Loire-Atlantique and Vendée Cancer Registry data. Annual percentage changes (APCs) were estimated using an age-adjusted Poisson regression model. RESULTS: Incidence rates of breast cancer increased 3.5% per year in 1991-2003, dropped -4.3% per year in 2003-2006 and increased in 2007 (9.1%). Stratified analyses by age groups showed that the decrease concerned predominantly women aged 50-64 years, whereas an increasing proportion of cancers detected by organized screening was observed in this age group. Among these women, the decline of incidence particularly concerned positive estrogen and progesterone receptor tumors, lobular subtype tumors, and low-grade tumors. CONCLUSION: The drop in breast cancer incidence rates observed between 2003 and 2006 in women 50-64 years old was greater for ER+PR+ tumors. During the same period, the incidence of breast cancers diagnosed by organized screening increased. These patterns appear consistent with an impact of the reduced use of HRT.