Health-related quality of life among women diagnosed with in situ or invasive breast cancer and age-matched controls: a population-based study

A breast cancer (BC) diagnosis may negatively affect health-related quality of life (HRQoL). However, there are few comparisons of HRQoL at several time points for women with BC, and particular when subdivided into invasive and in situ tumors. The purpose of this study was to investigate various aspects of HRQoL in women recently diagnosed with invasive BC or ductal carcinoma in situ (in situ) compared to age-matched BC free controls in a population-wide sample recruited through the Cancer Registry of Norway. This cross-sectional study utilized HRQoL data collected in 2020–2022 from a digital survey including 4117 cases (3867 women with invasive BC and 430 with in situ) and 2911 controls. HRQoL was assessed ≥ 21 days after diagnosis, using EORTC QLQ-C30. This includes scores assessing global quality of life (gHRQoL) and HRQoL functions and symptoms. Multivariable regression analyses were used to compare HRQoL between cases and controls and to identify factors associated with gHRQoL and fatigue. Additionally, HRQoL 14 months after diagnosis was analyzed in 1989 of the included cases and in 1212 of the controls. Score differences of ≥ 10 points were considered clinically relevant and thus presented in the results. Invasive BC cases had lower gHRQoL, role- and social functioning in addition to more fatigue than controls. In situ cases had lower role—and social functioning than controls. Invasive BC cases scored worse than in situ on all domains, but the differences were not considered clinically relevant. Physical activity was associated with better gHRQoL and less fatigue in invasive BC, in situ and controls. Both invasive BC and in situ cases improved their role- and social functioning scores from diagnosis to 14 months follow-up, however no improvement was seen for fatigue. Women with invasive BC and in situ reported lower role- and social functioning scores than controls right after diagnosis with improvements 14 months after diagnosis. Physical activity was associated with better gHRQoL and less fatigue and should, whenever possible, play a key role in the care for BC patients.