Objective
Ductal carcinoma in situ (DCIS) is a risk factor for invasive breast cancer (IBC). The prognosis of DCIS is considerably better than for IBC, yet women do not distinguish between the threat. We aimed to compare the psychosocial consequences of screen-detected DCIS and IBC, and to examine this comparison over time.

Methods
We surveyed a Danish mammography-screening cohort from 2004 to 2018. We assessed outcomes at six-time points: baseline, 1, 6, 18, 36 months, and 14 years after the screening. We measured psychosocial consequences with the Consequences Of Screening – Breast Cancer (COS-BC): a condition-specific questionnaire that is psychometrically validated and encompasses 14 psychosocial dimensions. We used weighted linear models with generalized estimating equations to compare responses between groups. We used a 1% level of significance.

Results
170 out of 1309 women were diagnosed with breast cancer (13.0%). 23 were diagnosed with DCIS (13.5%) and 147 with IBC (86.5%). From baseline to six months after diagnosis, there were no significant differences between women with DCIS and IBC. However, mean scores indicated that IBC generally was more affected than DCIS. After six months, we observed that women with DCIS and IBC might be affected differently in the long term; mean scores and mean differences showed that IBC were more affected on some scales, while DCIS were on others.

Conclusion
Overall, the DCIS and IBC experienced similar levels of psychosocial consequences. Women might benefit from renaming DCIS to exclude cancer nomenclature.