• Description of Indicators

• Tables of national indicators for the years 2008 to 2020

• Summary of indicators for the years 2008 to 2020

• Tables of regional indicators for the years 2008 to 2020

The data cover all screenings performed between January 1, 2008, and December 31, 2020, under the PNDOCS program in all French departments. For the 2019–2020 period, 4% of screenings were first screenings under the PNDOCS program with no prior mammography history, 13% were first organized screenings with a history of mammography (most often as part of an individual screening), and 83% were subsequent organized screenings, meaning participation in the PNDOCS for the second time or more. This distribution is the same in 2019 and 2020, and has remained stable since 2008.

The indicator tables are broken down by age, percentile, and region. They provide information on the number of women screened, screening results, diagnostic evaluations, the number of cancers detected and their characteristics over the period in question, as well as the corresponding rates and percentages. The summary of indicators presents the main results regarding positive screenings and detected cancers for the entire 50–74 age group and for follow-up screenings.

Over the 2019–2020 period, more than 4,100,000 women underwent a follow-up screening under the PNDOCS program, including 2,119,779 in 2019 and 1,903,261 in 2020.

Subsequent positive screenings

(Summary - Table 1, Figure 1)

In 2019–2020, the rate of positive screening results (standardized to France 2009) on the first reading (R1) before diagnostic evaluation was 6 per 100 women screened. After immediate diagnostic evaluation (BDI), it drops to 2.8 per 100 screened women. Taking the second reading (L2) into account, the rate of positive screenings before evaluation in L1 and L2 is 7 per 100 screened women. There are no notable variations between 2019 and 2020. Since 2008, the rates of positive screening results before evaluation have been declining slightly, while the rates after evaluation have remained stable, indicating an improvement in screening practices during the first reading.

Cancers detected by follow-up screening

(Summary - Table 2, Figures 2–5)

The figures regarding cancers are not entirely final for recent years, as some cases may be updated in upcoming data reports from the CRCDC.

In 2019, 16,202 cancers were detected, and 14,800 in 2020. The cancer detection rate is steadily increasing, rising from 6.2 per 1,000 screened in 2008 to 7.2 in 2020. This trend is consistent with the observed increase in breast cancer incidence in the general population. While this trend is similar across all regions, there are variations in levels, with a higher detection rate in Hauts-de-France and a lower one in the DROMs. These differences in levels are consistent with the incidence rates observed in these regions.

The proportion of cancers with a favorable prognosis among all detected cancers are important indicators for evaluating the program’s performance. Among women undergoing follow-up screening in 2020, 13.8% of cancers with known invasive/in situ status were in situ cancers, 36.8% of invasive cancers of known size were 10 mm or smaller, and 79.9% of invasive cancers with known lymph node status were lymph node-negative. These results were consistent with European benchmarks (desirable rates of 10% to 20% for in situ cancers, ≥30% for cancers ≤10 mm in size, and >75% for cancers without lymph node involvement). It should be noted that these figures were slightly lower in 2020 compared to 2019, a trend that will need to be confirmed in the next update. Since 2008, a slight downward trend in the proportion of in situ cancers and small-sized cancers has been observed, while the trend appears to be upward for the proportion of cancers without lymph node involvement. Differences in proportions are observed across regions, which may be linked both to the specific epidemiology of each region and to significantly different practices at the various stages of this screening.

The proportion of cancers detected at L2 in 2020 was 4.8 per 100 invasive or in situ cancers. The proportion of cancers detected at L2 has been steadily declining since 2008, but still accounts for approximately 1,500 cancers detected through this dual L2 review during the 2019–2020 period.

Positive predictive value

(Summary - Table 2, Figure 6)

The PPV of screening mammography prior to diagnostic evaluation—that is, the probability of having cancer if the screening result is positive at L1 or L2 before evaluation—was 11.3% in 2020, a continuous increase since 2008, when it was 7.8%. This reflects a decrease in the number of false positives (screenings classified as positive without the presence of cancer), which can be explained by an improvement in screening quality starting at L1 prior to diagnostic evaluation.