Long-term effects following treatment of screen-detected versus symptomatic breast cancer
Background
In Norway, women aged 50 to 69 are invited to breast cancer screening every other year. The goal is to detect breast cancer at an early stage to provide less aggressive treatment and reduce the mortality from the disease.
Breast cancer survivors can experience a wide range of complications and late treatment effects that affect their long-term quality of life. These may include side effects related to heart and lung function, altered pregnancy and childbirth opportunities, development of arm lymphedema, neuropathy, skin changes and chronic pain and fatigue. Psychosocial consequences, such as depression and anxiety, can also be caused by breast cancer treatment.
We do not know enough about the relationships between breast cancer detected by screening, long-term effects of treatment and the impact on women’s long-term quality of life. Breast tumors detected by screening ("screen-detected cancers") are often smaller and have less frequently spread to other parts of the body than breast tumors detected due to symptoms such as a lump. Does the less aggressive treatment for screen-detected breast cancer result in fewer serious and long-lasting effects for women compared to the treatment of breast cancer detected due to symptoms?
To the best of our knowledge, no breast cancer survivor studies have investigated whether long-term quality of life differs for women whose breast cancers were detected by screening compared to those whose breast cancer was detected due to symptoms.
Aim
The aim of this project is to investigate the long-term effects of breast cancer diagnosis and treatment for women with screen-detected versus symptomatic breast cancer.
We will also examine the effect of whether breast cancer is screen-detected, detected between two screening examinations/appointments ("interval cancers") or detected outside of the screening program. In addition, we will investigate whether tumor characteristics (tumor diameter, histological grade and lymph node and receptor status) are associated with women’s long-term quality of life.
Method
The project involves a retrospective study. Information from a random sample of women aged 50-69 will be retrieved from the Cancer Registry database. We will include 4000 women without breast cancer and 7500 with breast cancer. Our study will include an equal number of women who have screen-detected cancers, interval cancers, and cancer detected outside of the screening program.
We will use a questionnaire to obtain self-reported information on women`s treatment, quality of life, and any treatment effects experienced 1 to 12 years after diagnosis. The results of the questionnaire and data on tumor characteristics will be compared between the different groups of women with and without breast cancer.
Quality-adjusted life years will be used to measure the burden of long-term effects. Quality-adjusted life years encompass the length of life and are often measured as the person’s ability to perform daily life activities without pain and mental disturbance.
Planned studies and status
In 2020, the project group sent out questionnaires to 11,500 women in the target group of BreastScreen Norway. The questionnaires have been collected and registered at the Cancer Registry, and data analyzed.
Study 1: Long-term quality of life among breast cancer survivors with screen-detected breast cancer - a review study.
Published: Moshina N, Falk RS, Hofvind S. Long-term quality of life among breast cancer survivors eligible for screening at diagnosis: a systematic review and meta-analysis. Public Health. 2021, doi: 10.1016/j.puhe.2021.08.008
Study 2: Long-term quality of life after breast cancer treatment among women with screen-detected versus symptomatic breast cancer.
Published: Moshina N, Falk RS, Botteri E, Larsen M, Akslen LA, Cairns JA, Hofvind S. Quality of life among women with symptomatic, screen-detected, and interval breast cancer, and for women without breast cancer: a retrospective cross-sectional study from Norway. Qual Life Res. 2021, doi: 10.1007/s11136-021-03017-7
Study 3: Quality of life after breast cancer treatment among women who attended screening versus women who were invited but did not attend. In progress.
Data protection
Information from the women who provide their written consent to participation will be used in the study. The consent form is attached to the questionnaire that the women receive.
Women who have expressed their willingness to participate in the study have the right to access the information we have registered about them. These women also have the right to correct any errors in the information we have recorded. Only information processed in the study can be accessed. This means information from the questionnaire may be accessed. Other information included in the study will not be available, such as detailed health information on cancer treatment and biological properties of tumors, as it will demand a disproportionate amount of effort. In these cases, access to information would have to be requested from the primary source in accordance with the rules that apply to access data from the Cancer Registry.
