Surgery or Monitoring? Clinical Trial Seeks Answers for Low-Risk DCIS Breast Cancer.

Surgery or Monitoring? Clinical Trial Seeks Answers for Low-Risk DCIS Breast Cancer.

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MedStar Health Research Institute investigators and patients are participating in an exciting national study to determine whether low-risk DCIS breast cancer is  better treated with standard cancer therapies or active monitoring.


Ninety-seven percent of patients in the U.S. undergo surgery to remove ductal carcinoma in situ (DCIS)—precancerous lesions in the breast’s milk ducts. About one-third of these surgeries are mastectomies, and almost half of the patients also have radiation therapy. Yet studies suggest that more than half of patients with low-risk DCIS may never develop invasive breast cancer.


This has led to a growing number of researchers—including MedStar Health Research Institute— asking whether patients can avoid potentially unnecessary treatments and side effects that can significantly reduce the quality of life, including pain, scarring, and medical costs.


Our researchers are participating in a first-of-its-kind clinical study, Comparing an Operation to Monitoring, with or without Endocrine Therapy (COMET), to determine whether patients who do not have aggressive DCIS can avoid surgery and participate in active monitoring instead.


Doctors assess DCIS as grade I-III, from lowest to highest risk of developing invasive breast cancer. Previous research considered data from all grades, resulting in sweeping recommendations for surgery.


COMET is the first clinical research trial of its kind to directly compare surgery and active monitoring for patients with low-risk DCIS. This Phase III study funded by the Patient-Centered Outcomes Research Institute (PCORI) is now enrolling 1,200 patients at medical centers across the country—including at MedStar Health.

Surgery vs. active monitoring for low-risk DCIS.

In the COMET study, patients are randomly assigned to receive either surgery to remove the DCIS or treatment with active monitoring.


Patients who have surgery will receive the standard procedure for their DCIS, either a lumpectomy (removal of a portion of the breast) or mastectomy (removal of the whole breast), depending on the size of the DCIS and the surgeon’s recommendation. Patients who participate in active monitoring will get mammograms every six months to check for changes in the breast tissue. If no changes are detected, patients will remain in the monitoring program. If changes develop , the patient and doctor will discuss whether surgery is needed.


With either option, patients and their doctors can decide whether to take medicines to block hormones associated with cancer growth (endocrine therapy).


Treating breast cancers with a team approach.

Not all patients with DCIS will qualify for the COMET trial, but we’re already seeing great enthusiasm among eligible patients. To qualify for COMET, a woman must:

  • Be at least 40 years old
  • Have a recent diagnosis of low-risk DCIS
  • Have no history of breast cancer or DCIS five years before her current DCIS diagnosis
  • Have no mass on physical exam or imaging

MedStar Health has built a dynamic team of breast cancer experts who care for the holistic health of our patients throughout their cancer diagnosis and treatment. Moreover, our cancer support services team helps patients access rehabilitation, genetic counseling, support groups, survivorship programming, and other critical services.


We hope the COMET trial will demonstrate that many patients with low-risk DCIS can get the most effective, least invasive breast cancer care, sparing more women from unnecessary lumpectomy, mastectomy, and radiation. In the process, we hope to significantly improve the quality of life for the many people for whom cancer surgery is unnecessary.


Want more information about this study?

Learn more about eligibility criteria and how to enroll.

Call 833-998-0900 or Contact

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