Breast cancer
The incidence of breast cancer has increased significantly in recent decades. In 2022, there was more than twice as much breast cancer among Norwegian women as in 1958. Every year, 25-30 men are affected by breast cancer, and the incidence for men has been stable for the past 50 years.
For those affected by this disease, the prospects of survival are steadily improving, and those who do not recover live longer with the disease.
In addition to previous diagnosis, great progress has been made in the treatment of breast cancer in recent years.
Risk factors
There is no single reason why more and more women are getting breast cancer.
However, we know of several risk factors for the disease. The risk of breast cancer increases with age. Most cases occur after the age of 50. Therefore, Norwegian women are invited to mammography screening from about the age of 50. Women who have breast or ovarian cancer in their family may also be at increased risk. Between 5 and 10 percent of breast cancer cases may be due to heredity. How early children are born, how many babies are born, and the extent to which breastfeeding children have also been shown in large studies to be associated with breast cancer risk.
Several lifestyle factors can increase the risk of getting breast cancer. Obesity after menopause, alcohol intake and lack of physical activity can increase the risk. Long-term use of hormone supplements with the combination of oestrogen and progestogen in connection with menopause also increases the risk of breast cancer.
Read about risk factors and prevention for breast cancer on kreftforeningen.no
Read about cancer prevention on kreftregisteret.no
New cases
4224 women and 23 men contracted breast cancer in Norway in 2022. The number of cases per 100,000 people is 144.1 for women and 0.8 for men.
In the period 2018-2022, 42.8 per cent of cases in women were detected in stage I (early, local stage), while 28.9 per cent were detected in stage II and 9.8 per cent in stage III. 4.4 per cent had distant metastasis, stage IV, at the time of diagnosis, while 14 per cent had an unknown stage.
Aging
The median age for breast cancer is 62 years, which means that half of all those diagnosed are over 62 years of age.
Occurance of breast cancer by age at diagnosis, 1982–2022. From figure 3.1 in the Breast Cancer Registry's annual report 2022.
For the age group 30-39 years, a steady incidence is seen throughout the period, but a slight increase has been seen in recent years.
There is a steady increase in the incidence rates for the age group 40–49 years throughout the period.
There was a marked increase in the incidence for the age group 50–69 years related to the gradual introduction of breast cancer screening from 1996, combined with an increase in HT during menopause.
Due to COVID-19 with reduced activity in the Mammography Programme in 2020, there was a decline in the number of diagnoses. In 2021, the incidence increased significantly in this age group, a slight decrease is seen in 2022.
The incidence of breast cancer in Norway has been fairly steady for the 70+ age groups from 1985-2008, but with an increase in recent years, continuing in 2022.
Survival
Breast cancer survival has gradually improved, and 9 out of 10 women affected are alive 5 years after diagnosis.
Five-year relative survival in the period 2018-2022 totals (all stages) is 92.5 percent. The survival rate for patients with distant metastasis is significantly lower; 39.1 per cent.
Relative survival of breast cancer up to 15 years after diagnosis, distributed by age in the period 2018-2022. From Fig. 8.1-L in Cancer in Norway 2022.
Survivors with breast cancer
At the end of 2022, there were 57,118 people who had recovered from or were living with breast cancer diagnosed over the past 15 years.
More than 26,000 of these were diagnosed more than 10 years ago.
Number of deaths
587 women and 4 men died of breast cancer in Norway in 2021.
Development over time
Trends in incidence (red), mortality (pink) and 5-year relative survival (brown) of breast cancer among women in the period 1965-2022. Fra Cancer in Norway 2022, fig. 9.1-M.
There is a steady incidence for the 70+ age groups from 1985-2008, and there is an increase in recent years. There is a marked increase in incidence for the age group 50-69 years following the gradual introduction of breast cancer screening from 1996, combined with an increase in hormone therapy during menopause. There is a steady increase in the incidence rates for the age group 30–49 years throughout the period.
The proportion of women who are alive 5 years after being diagnosed with breast cancer has increased sharply. In the late 1970s, 5-year relative survival was 73.4 percent. In the last five-year period, survival has increased to more than 90 per cent.
There is a marked decline in breast cancer mortality from the mid-90s to the present.
National Quality Registry for Breast Cancer
The Breast Cancer Registry was granted national status in 2013, but has registered data since 2009. The Cancer Registry of Norway is responsible for data processing, and a professional council has been established in the registry.
The purpose of the National Quality Registry for Breast Cancer is to strengthen the quality of health care for patients with breast cancer. The registry shall also conduct, promote and provide a basis for research to develop new knowledge about the causes, diagnosis and course of cancer, as well as treatment effects.
Read more about the National Quality Registry for Breast Cancer
In order to fulfil the purpose of the registry, quality objectives from EUSOMA (European Society of Breastcancer Specialists) and recommendations from the National Action Programme with guidelines for diagnosis, treatment and follow-up of breast cancer are used.
The recommendations in the Action Programme are based on updated systematic knowledge and are intended to help ensure that the public provision of breast cancer care is of good quality and equal throughout the country.
The goal of breast-conserving surgery is for patients to have the same survival as with mastectomy. It is important to have good local control in the surgical area during surgery and thus ensure a low risk of recurrence/relapse.
The figure shows the proportion of breast-conserving operations for invasive breast cancer among women with tumour size 0–30 mm, distributed by operating hospital, operating year 2021–2022. From Fig. 3.21 in the Annual Report of the National Quality Registry for Breast Cancer 2022.
In 2022, there were 2087 breast cancer surgeries with tumour sizes 0–30 mm and of these, 87.4 % underwent breast-conserving surgery, which gives a high goal achievement for Norway overall. 42.5 % were detected by mammography screening. 11 hospitals achieved a high goal attainment of 85 %. EUSOMA's 11c quality goal recommends that breast-conserving surgery should be performed in a minimum of 70 % of women, with a target of 85 %.
There are 331 cases of multifocal tumours excluded in the figure and 61.6% of these had breast-conserving surgery in 2022.
Note that differences in patient groups between different hospitals in combination with few patients may affect the results. It is not a goal to have 100 per cent, because an individual assessment must be made of each patient and the patient should also be able to remove the entire breast if she wishes to do so, provided that she is informed that breast-conserving surgery is a safe alternative.
See more results in this year's report
Patient-reported results
In 2019 and 2020, the Cancer Registry of Norway worked on planning and building infrastructure for collecting PROMs, including integration with ePROMs, which is the national solution for collecting PROMs.
Collection of PROM and PREM data for breast cancer began in the fall of 2020 for women diagnosed in 2020 through a permanent, three-year population survey on health and quality of life. For PROMs, women diagnosed with breast cancer are compared with a control group with women without breast cancer, but with matching age and place of residence.
Population-based health surveys
Results show that there is little change in perceived health-related quality of life 14 months after breast cancer patients were diagnosed compared to women without breast cancer. At the same time, breast cancer patients appear to have a higher degree of fatigue 14 months after diagnosis than women of the same age without breast cancer. The youngest women with breast cancer appear to have the highest degree of fatigue, while women of screening age (50-69 years) appear to have the least.
Proportion of patients who felt that they received sufficient information about possible side effects, distributed by operating hospital, diagnostic year 2021. From Fig. 3.39 in the Annual Report of the National Quality Registry for Breast Cancer 2022.
Of the women with breast cancer who responded to the survey, 61 % reported that they felt that they received sufficient information about possible side effects of the treatment, while 13 % state that they received little or no sufficient information about this to any great extent.
Breast cancer patients receive comprehensive treatment where all treatment modalities (surgery, radiation therapy, chemotherapy, anti HER2-directed therapy and antihormonal therapy) can cause side effects. The fact that 13 % of patients state that they do not feel that they receive sufficient information about adverse effects of the treatment indicates that more emphasis should be placed on providing such information to future patients.
See more results from patient-reported outcome measures in the annual report
Breast cancer screening
Some of the increase in the incidence of breast cancer can be attributed to the Mammography Programme, the organised screening against breast cancer offered to Norwegian women between 50-69 years. The programme detects more cases of cancer at an earlier stage than if the woman had waited until the symptoms appeared. This most likely improves survival for those affected.
Steps You Can Take to Reduce Your Risk of Getting Breast Cancer
- Have a healthy diet
- Keeping a healthy body weight
- Drink as little alcohol as possible
- Be physically active
- Avoid long-term use of estrogen supplements associated with menopause
- Examining their breasts themselves
Read more about risk factors for breast cancer on kreftforeningen.no
- By participating in the mammography programme, breast cancer can be diagnosed and treated at an early stage
Read about the mammography programme on kreftregisteret.no
Questions about cancer
The Cancer Registry of Norway is a research institution. Our professionals therefore do not answer questions about diagnosis, assessment, treatment and follow-up from patients or their relatives.
Questions about this should be directed to your own GP, treating institution or the Cancer Society Advisory Service tel: 21 49 49 21
Useful Links
Read about breast cancer at helsenorge.no
