Abstract
BACKGROUND
The current debate on overdiagnosis and overtreatment of screen-detected ductal carcinoma in situ (DCIS) urges the need for prospective studies to address this issue. A substantial number of DCIS lesions will never form a health hazard, particularly if it concerns non- to slow-growing low-grade DCIS. The LORD study aims to evaluate the safety of active surveillance in women with low-risk DCIS.
FEASIBILITY
To explore interest in and feasibility of the LORD study we conducted a survey among EORTC and BOOG centres. A vast majority of EORTC and BOOG responding centres expressed interest in participation in the LORD study. The proposed study design is endorsed by nearly all centres.
DESIGN
This is a randomised, international multicentre, open-label, phase III non-inferiority trial, led by the Dutch Breast Cancer Research Group (BOOG 2014-04) and the European Organization for Research and Treatment of Cancer (EORTC-BCG 1401). Standard treatment will be compared to active surveillance in 1240 women aged ⩾ 45 years with asymptomatic, screen-detected, pure low-grade DCIS based on vacuum-assisted biopsies of microcalcifications only. Both study arms will be monitored with annual digital mammography for a period of 10 years. The primary end-point is 10-year ipsilateral invasive breast cancer free percentage. Secondary end-points include patient reported outcomes, diagnostic biopsy rate during follow-up, ipsilateral mastectomy rate and translational research.