Little is known about quality-of-life (QOL) differences over time between incident ductal carcinoma in situ (DCIS) and early-stage invasive breast cancer (EIBC) cases as compared with same-aged women without breast cancer (controls). We prospectively recruited and interviewed 1,096 women [16.8% DCIS, 33.3% EIBC (25.7% Stage I; and 7.6% Stage IIA), 49.9% controls; mean age 58; 23.7% non-white] at mean 6.7 weeks (T1), and 6.2 (T2), 12.3 (T3), and 24.4 months (T4) after surgery (patients) or screening mammogram (controls). We tested two hypotheses: (1) DCIS patients would report lower levels of QOL compared with controls but would report similar QOL compared with EIBC patients at baseline; and (2) DCIS patients' QOL would improve during 2-year follow-up and approach levels similar to that of controls faster than EIBC patients. We tested hypothesis 1 using separate general linear regression models for each of the eight subscales on the RAND 36-item Health Survey, controlling for variables associated with at least one subscale at T1. Both DCIS and EIBC patients reported lower QOL at T1 than controls on all subscales (each P<0.05). We tested hypothesis 2 using generalized estimating equations to examine change in each QOL subscale over time across the three diagnostic groups adjusting for covariates. By T3, physical functioning, role limitations due to physical problems, energy/fatigue, and general health each differed significantly by diagnostic group at P<0.05, because of larger differences between EIBC patients and controls; but DCIS patients no longer differed significantly from controls on any of the QOL subscales. At T4, EIBC patients still reported worse physical functioning (P=0.0001) and general health (P=0.0017) than controls, possibly because of lingering treatment effects. DCIS patients' QOL was similar to that of controls two years after diagnosis, but some aspects of EIBC patients' QOL remained lower.