DCIS Active Monitoring Clinical Trials
Clinical Trials
We believe women deserve to understand all available options when diagnosed with ductal carcinoma in situ (DCIS), including the growing research supporting active monitoring for carefully selected low-risk cases.
This page highlights important clinical trials such as COMET, LORD, PORTAL, and RECAST, which are exploring whether some women can safely avoid immediate surgery, radiation, and endocrine therapy while being closely monitored over time. Emerging research continues to raise concerns about overdiagnosis and overtreatment of low-risk DCIS, while emphasizing the importance of personalized risk assessment, informed consent, and patient-centered decision-making.
COMET Study Patient Advocates
While clinical trials are not for everyone, they play an important role in advancing the much-needed paradigm shift for better communication about DCIS as well as de-escalation of aggressive “standard of care” treatments. By sharing the latest studies, expert perspectives, and advocacy efforts, DCIS 411 aims to empower women with balanced information so they can make individualized choices aligned with their health goals, personal values, and quality of life.
Below are clinical trials of interest to many involved with DCIS, from patients to researchers to advocates.
The COMET Study
COMET stands for Comparing an Operation to Monitoring, with or without Endocrine Therapy for low-risk DCIS.
While COMET is no longer enrolling new participants, the study will continue to follow women for 10 years.
Results released in December 2024 showed women in the active monitoring group were no more likely to develop invasive breast cancer in the same breast after two years compared to those who underwent surgery.
Conclusions and Relevance: “Women with low-risk DCIS randomized to active monitoring did not have a higher rate of invasive cancer in the same breast at 2 years compared with those randomized to guideline-concordant care.”
Background on the Comet Study
Introduction
“Annually, approximately 65 million women undergo mammographic screening in the US at a cost of more than $13 billion.1 Although mammography has been associated with a reduction in breast cancer mortality rates,2,3 there is increasing concern that this benefit has been accompanied by overdiagnosis and overtreatment.4 Overdiagnosis occurs when cancer screening detects conditions that may never cause harm if left untreated; treatment for these conditions provides no survival benefit and can result in harm.
For breast cancer, much of the burden of overdiagnosis is thought to derive from the detection of ductal carcinoma in situ (DCIS), a diagnosis faced by more than 50 000 women in the US annually.5,6 DCIS is a preinvasive neoplasia that lacks the potential to spread and cause symptoms unless it undergoes progression to invasive cancer. When diagnosed, DCIS is conventionally treated with surgery, often combined with adjuvant radiation, and/or endocrine therapy.7,8 These treatments are the same as those recommended for women with low- to intermediate-risk invasive cancer. Adverse effects of these therapies can include long-term pain, altered body image, sexual dysfunction, menopausal symptoms, or, rarely, secondary cancers.9 Because not all DCIS progresses to invasive cancer,10–13 there is a potential opportunity to deescalate surgery in the management of DCIS.” Read more here.
LORD: (LOw Risk DCIS) Study
“For decades, DCIS was framed as ‘early-stage breast cancer.”
As a result, it has almost always been treated in the same way as breast cancer. But if most DCIS will never become dangerous, an important question arises: are some women receiving more treatment than they need?
“As a doctor, I am guided by the principle ‘first, do no harm.’ My motivation for starting the LORD trial was simple: to help make care safer and more balanced. We wanted to find out whether carefully selected women with low-risk DCIS can be safely monitored with regular checkups, known as active surveillance, instead of having immediate surgery. The goal is to avoid unnecessary treatment without putting women at risk.” – Professor Jelle Wesseling from The Netherlands Cancer Institute and Leiden University Medical Center
LORD Brief Summary
“A substantial number of DCIS lesions will never form a health hazard, particularly if it concerns slow-growing low-risk DCIS (grade I and II). This implies that many women might be unnecessarily going through intensive treatment resulting in a decrease in quality of life and an increase in health care costs, without any survival benefit.
The LORD (LOw Risk DCIS) study is a non-randomized, international, multicenter, phase III non-inferiority trial, and aims to determine whether screen-detected low-risk DCIS can safely be managed by an active surveillance strategy…
Background of the study:
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-risk DCIS (grade I and II DCIS) can safely be managed by active surveillance. If progression to invasive breast cancer would still occur, this will be lowgrade 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-risk DCIS patients from intensive treatment.
Read more here.
Comparing Two Treatment Approaches for Women with Ductal Carcinoma In Situ (DCIS) — The PORTAL Study
Background:
More than 62 000 women are diagnosed with ductal carcinoma in situ (DCIS) in the United States annually. Without treatment, approximately 20% to 30% of DCIS will progress to invasive cancer. However, 97% of women are treated according to guideline-concordant care (GCC) (surgery and/or radiation). An alternative for low-risk DCIS is active surveillance (AS), where mammography and physical examinations are used to monitor potential breast changes. Evidence from registries and collection of patient-reported outcomes is critical to understanding the benefits and harms of GCC vs AS for DCIS.
Read more here.
DCIS RECAST (Re-Evaluating Conditions for Active Surveillance Suitability as Treatment)
“With the objective to avoid over-treatment of low-risk DCIS patients, this new trial offers DCIS patients endocrine therapy with the intent to identify patients who are responsive to non-invasive treatment and have the option to omit surgery and be monitored via long-term active surveillance. A key element in reducing over treatment of DCIS is identifying biomarkers that reflect the risk of progression so that those with low-risk lesions are spared surgery. RECAST DCIS features the assessment of MRI imaging and molecular-based biomarker analyses in addition to evaluating new investigational agents in this setting. If patients and their physicians agree, they may be able to stay on endocrine therapy for up to three years.” Read more here.