Breast Cancer Prevention

Doctors call for less invasive methods to treat ductal carcinoma in situ (DCIS) 

The Parsemus Foundation encourages research on simple approaches that could have a big impact, including the intraductal approach to early breast cancer — preventing, or eliminating, early cellular changes in the milk ducts (where the great majority of breast cancers start). When these changes are detected, the condition is called ductal carcinoma in situ (DCIS) — the most common noninvasive lesion of the breast. With mammography becoming standard practice, the diagnosis of DCIS has skyrocketed, now accounting for over 20% of breast cancer diagnoses. Surgery, radiation, and hormone therapy are standard therapies, despite the fact that only a portion of DCIS cases progress to invasive cancer.

But scientists and physicians have been increasingly questioning the aggressive traditional treatment of DCIS. This pre-cancerous condition may be over-diagnosed and over treated in the U.S., and clinical trials have shown that while radiation and hormone therapy can reduce the risk of invasive recurrence, they have no effect on survival. There has been a call for tailoring the treatment to the woman, and carefully evaluating risks. Newer molecular profiling may serve to more effectively predict whether the condition will progress (see reviews by Feinberg and colleagues, 2018 and Barrio & Van Zee, 2017, and information on molecular evaluation by Nofech-Mozes et al, 2019).

Intraductal treatment of DCIS for breast cancer prevention and evaluation

Increasing evidence suggests that evaluating and even treating DCIS through the breast ducts can be an effective nonsurgical alternative. Dr. Susan Love has been an advocate of the intraductal approach for years, with research studies focused on mapping the breast ducts with 3D ultrasound. Ductal lavage, ductoscopy, and intraductal infusion of therapeutic agents may enhance breast cancer treatment. See details below.

• Intraductal lavage involves flushing the mammary ducts and collecting the fluid for analysis of the cells. This method is becoming more common, especially for women at high risk of breast cancer. While the sensitivity required to detect abnormal cells visually is not ideal, evaluation of molecular indicators in the fluid is proving to be a useful diagnostic tool.
• Mammary ductoscopy (threading a tiny endoscope into the breast ducts) is a noninvasive method that can help to visualize and sample lesions. Ductoscopes have been developed with fiber optics to aid visualization. This method can also be used to guide lumpectomy surgery, which helps to avoid the additional surgeries that may be required when lesions are missed with traditional methods.
• Intraductal infusion is a method to put therapeutic agents directly into the duct system, where most breast cancers originate. It’s less likely to cause systemic toxicity since the physician is targeting a specific area. A number of clinical trials of intraductal chemotherapy have indicated the safety and feasibility of this method for breast cancer prevention.