According to data from Bulgarian National Cancer Registry (BNCR), breast cancer is the most common oncological disease in Bulgaria. Since 2012 every year in Bulgaria have been diagnosed between 3500 and 4000 new cases. In the last years number of the registered cases is decreasing. From one side this is due to lack of data in the Registry from many hospitals, but mostly it is because the Bulgarian population is decreasing, which was seen in the last caunt of Population in 2021. Despite of the high number of oncological cases in the recent years and the demographic crisis there is also a problem with suboptimal or missing registration.
Bulgaria is the only country on the Balkans which has a National Cancer Registry.
Therefore if the registration of oncological diseases in Bulgaria stops there will be no epidemiological data not only from Bulgaria, but on the Balkans as whole.
BNCR is sending data every year to the international agency for research on cancer https://gco.iarc.fr/ and the European information system https://ecis.jrc.ec.europa.eu/ . From those sources it is obvious, that Bulgaria is not from the countries with the highest burden of breast cancer, but is on one of the last places in Europe according to the 5 year survival rate. Recent publications are also confirming those trends.
Dafni U, Tsourti Z, Alatsathianos I. Breast Cancer Statistics in the European Union: Incidence and Survival across European Countries. Breast Care (Basel). 2019 Dec;14(6):344-353. doi: 10.1159/000503219. Epub 2019 Oct 8. PMID: 31933579; PMCID: PMC6940474.
In Bulgaria, there is no national screening program for the early diagnosis of breast cancer, which means that the initiative to examine the breast for the purpose of early diagnosis is in the hands of the patient, or it is the so-called opportunistic screening.
The National Health Insurance Fund covers, with a GP referral, an echomammographic (ultrasound) examination of the breast every 2 years for patients between 30 and 50 years old without complaints, and for women between 50 and 69 years old, again without complaints – a mammographic examination of the breast, also at every 2 years. For women with chest complaints, the GP can order an echomammography as needed at any time.
Bulgaria is one of the countries with the lowest survival rate from oncological diseases, including breast cancer, in the European Union. The latest data are from the CONCORD 3 study, which included patients diagnosed up to 2014. In Bulgaria, the 5-year age-related survival from breast cancer is 78.3%, which is about 8-10% lower than the 5-year survival in countries such as Belgium and Sweden. In Belgium, a national population-based breast cancer screening program was introduced in 2001 and participation in the program has been shown to reduce the risk of breast cancer mortality by 50% compared to patients screened opportunistically. In Sweden, national population-based screening for breast cancer was introduced in 1997 and covers nearly 80% of women within the country’s borders. This results in up to a 41% reduction in the risk of death from breast cancer for women participating in screening compared to those not participating. In Bulgaria, more recent data on the mortality and survival of patients with breast cancer are missing due to the currently non-functioning National Cancer Registry.
According to the current recommendations of the European Commission, all women between the ages of 45 and 74 are subject to organized screening. At the age of 45 to 49, mammography should be performed every 2 or 3 years. Between the ages of 50 and 69, a mammogram should be carried out every 2 years, and between the ages of 70 and 74 again – a mammogram every 3 years. These recommendations take into account the effectiveness of screening, the potential for overdiagnosis of breast cancer, and the potential harms of screening.
Mammography should be performed on both breasts in 2 projections, that is, a total of at least 4 images are required. These total of 4 images deliver a radiation dose of between 3 and 5 mGy to the glandular tissue. The risk of developing breast cancer from this radiation dose is many times smaller than the benefit of detecting breast cancer with a well-conducted, high-quality mammogram. A dose of 3mGy is obtained from the Earth’s natural radiation background in 6 weeks. This means that if we live for 6 weeks, it is as if we had a screening mammogram.
The American Cancer Society in its large study found that the risk of death from breast cancer as a result of the dose received at screening (in America, screening mammography is recommended annually from 40 to 55 years and every two years from 55 to 74 years) is 10.7 per 1,000,000 women, and the benefit per breast cancer death averted from screening was 497 per 100,000 women, or a benefit-risk ratio of 47:1. in favor of screening mammography.