Abstract CT137: Standard therapy versus active surveillance for low grade DCIS: the LORD trial

Abstract

Abstract The introduction of population-based breast cancer screening and implementation of digital mammography have led to an increased incidence of ductal carcinoma in situ (DCIS) without a decrease in the incidence of advanced breast cancer. This suggests DCIS overdiagnosis exists. We hypothesize that asymptomatic, low-grade DCIS can safely be managed by active surveillance. If progression to invasive breast cancer would still occur, this will be low-grade and hormone receptor positive with excellent survival rates. Also, breast-conserving treatment will still be an option, if no prior radiotherapy has been applied. It also may save many low-grade DCIS patients from intensive treatment. We will compare active surveillance with conventional treatment, being either wide local excision (WLE) only, WLE plus radiotherapy or mastectomy, possibly followed by hormonal therapy for primary low-grade DCIS, detected by calcifications only, in a phase III, open-label, non-inferiority, multi-center, randomized clinical trial legally supported by the Breast Cancer Group of the European Organisation for the Research and Treatment of Cancer (EORTC-1401-BCG). The Dutch Centers are coordinated by the BOOG Study Center (BOOG 2014-04). Randomization will be 1:1 in to one of the following arms: active surveillance or standard treatment per local policy. In total, 1240 women (≥ 45 years) with asymptomatic, pure, low-grade DCIS, based on vacuum-assisted biopsies of calcifications as detected by population-based or opportunistic screening, without prior breast cancer, will be included. Assuming 25% of randomized women qualified to enroll in the study will drop out or will be excluded from per protocol population, at least 1,240 women need to be randomized to obtain the 930 patients required for the evaluation of the primary endpoint. The same follow-up scheme will be applied in both study arms, i.e. annual mammography for a period of 10 years. The primary end-point is ipsilateral invasive breast tumor-free rate at 10 years. Secondary end-points are among others: overall survival, breast cancer-specific survival, mastectomy rate and patient reported outcomes. Accrual has started in January 2017. Acknowledgements: This trial is funded by Pink Ribbon Netherlands, the Dutch Cancer Society and Dutch Cancer Society/Alpe d’HuZes. Citation Format: Jelle Wesseling, Frederieke van Duijnhoven, Konstantinos Tryfonidis, Aleksandra Peric, Elise van Leeuwen-Stok, Nina Bijker, Lotte Elshof, Emiel Rutgers. Standard therapy versus active surveillance for low grade DCIS: the LORD trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT137. doi:10.1158/1538-7445.AM2017-CT137