Every year, around 60,000 women in the United States are told by their doctors that they have a relatively early stage of breast cancer commonly known as Stage 0, which is considered to be a precursor to what could eventually become a life-threatening tumor.
Many of these women would often choose to undergo either a mastectomy, lumpectomy, or even double mastectomy, which effectively removes a healthy breast out of fear of developing the dreaded disease.
A new study featured in the journal JAMA Oncology, however, suggests that the treatment does not provide any difference in outcome, with several breast cancer patients dying of the disease despite undergoing treatment and not the absence of it.
Researchers, led by Dr. Steven Narod of the University of Toronto's Dalla Lana School of Public Health, examined a large number of data collected regarding the condition called ductal carcinoma in situ (DCIS). The data were gathered from 100,000 women during the course of a 20-year study.
The results of the study are expected to raise questions regarding the choice of tens of thousands of breast cancer patients to undergo unnecessary and highly invasive procedures in order to treat premalignant conditions that are not likely to develop into deadly cancers.
The numbers of DCIS diagnoses, which involve the confinement of abnormal cells in the breasts' milk ducts, have significantly increased in previous decades. These cases now account for around a quarter of cancer cases diagnosed through mammography, with radiologists discovering smaller and smaller lesions on patients' breasts.
The latest findings are viewed to likely cause a debate regarding the nature of DCIS cancer as either simply a risk factor for women or an actual precursor to the debilitating disease. It would also raise questions on the need for breast cancer patients to receive such highly invasive therapies, or if women should even be informed about the condition if the treatment does not even make a difference in outcomes.
While the study itself leads medical researchers to raise such provocative questions regarding DCIS, it does not appear to provide any resolutions. Some physicians, including the Memorial Sloan Kettering Cancer Center's chief breast cancer surgeon, stated that they did not see any need to change the approach that they currently follow.
Dr. Barnett S. Kramer, cancer prevention director at the National Cancer Institute (NCI), on the other hand, said that the new findings are helpful and that they are consistent with previous data pertaining to the same direction.
Kramer added that the study offers evidence that can help justify the need for treatments that are less morbid.
Breast cancer surgeon Dr. Laura J. Esserman, who wrote the accompanying editorial of the study, said that many of the 100,000 cancer patients examined by the researchers underwent lumpectomies, while the rest underwent mastectomies.
These patients experienced 3.3 percent likelihood to die of breast cancer in the 20-year period following treatment, regardless of which procedure they chose to take. This rate is about the same as that observed as the likelihood for an average woman to die of breast cancer.
The findings suggest that some of the patients had a higher risk to develop the disease, especially those who were younger than 40 years old, African-American and those whose abnormal cells contained molecular markers typically found in advanced forms of cancers with poorer prognoses.
"These women are not dying of DCIS," Narod said. "They die the conventional way from breast cancer—because it spreads to the bones, liver and lungs."
"The women who die of DCIS died because their breast cancer already spread by the time they received treatment."
The researchers noted that additional studies are needed in order to develop better methods of identifying DCIS lesions, potentially through the use of their genetic makeup, and distinguish them from those that are more or less likely to spread.
Photo: Gerry Lauzon | Flickr
