A new breast cancer clinical trial called COMET (NCT02926911) is now enrolling participants to evaluate the risks and benefits of a monitoring approach vs. a full-mode attack with surgery and other therapeutic approaches in women with low-risk ductal carcinoma in situ (DCIS).
DCIS is a condition characterized by the presence of abnormal (cancer-like) cells inside the breast milk ducts, and is considered the earliest form of breast cancer. The cells are confined to the ducts, however, and have not spread into the surrounding breast tissue, so it is considered noninvasive.
The American Cancer Society estimates that around 60,000 cases of DCIS are diagnosed each year in the United States, accounting for one out of every five new breast cancer cases. While DCIS is not considered life-threatening, 20 to 30 percent of women with this condition will eventually develop an invasive breast cancer later on.
So if DCIS is not invasive but may become invasive in the future, what should women do who are diagnosed with DCIS?
Most patients with low-risk DCIS follow guideline concordant care (GCC) and undergo surgery. The treatment options include lumpectomies (a procedure in which a lump is removed from the breast) often followed by radiation. Some, however, have full mastectomies (removal of both breasts). Others may also take anti-cancer therapies, such as tamoxifen, for several years.
But women who undergo surgical management of DCIS often report persistent pain at the surgical site and see it as a disability and cause of psychological distress.
Another option for these women is to undergo active surveillance, an option offered to low-risk patients that consists of close monitoring over time for signs of disease progression.
Choosing between these options, however, poses a conundrum. Should low-risk DCIS women be treated, even though many may never progress to invasive disease?
The study will determine whether low-risk DCIS women can be safely managed through active surveillance, with the approach not leading to more cancer cases or decreasing quality of life compared to the conventional therapies (guideline care).
Eligible patients for COMET are women who are at least 40 years old and have low-risk DCIS. Participants will be randomly assigned to either active surveillance or standard therapy, including surgery.
Those in the surveillance group will have regular doctor appointments and will undergo mammograms every six months. If a patient develops invasive cancer during the study, she will be able to move immediately to the treatment group, receiving either surgery or other type of therapy.
Tamoxifen and other hormone therapies will be offered to both groups to reduce the risk of recurrence.
The trial, which is actively enrolling patients, aims to recruit 900 participants at 100 medical centers nationwide. A key aspect of the study will be to assess participants’ physiological state: Do those in the surveillance group experience more anxiety because they aren’t fighting DCIS and are only monitoring it? Or do they benefit from a restrained approach?
The trial results may open possibilities for reducing overtreatment and disclose the real outcomes of patients under active surveillance relative to those undergoing conventional guideline care. Currently, fewer than 2,000 women with DCIS are receiving active surveillance in the U.S.