Older women with an early form of non-invasive breast cancer known as ductal carcinoma in situ (DCIS) gain no long-term benefit from undergoing a sentinel lymph node biopsy to see if the cancer has spread, a new study has found.
The research, carried out at the Yale School of Public Health, is believed to be the first to examine the long-term impact of sentinel lymph node biopsies on older women with DCIS.
It was found that the procedure did not reduce the patient’s likelihood of dying from breast cancer, decrease the chance of them developing breast cancer or decrease the number of additional cancer treatments needed. However, it did put patients at risk for pain, wound infection, and lymphedema as a result of the procedure.
Around 25% of breast cancer patients have DCIS, where cancer cells invade the milk duct in the breast.
Known as ‘stage zero’ breast cancer, DCIS is not generally considered life threatening due to its non-invasive nature, as the cancer cells do not spread beyond the milk duct. However, it can eventually develop into an invasive breast cancer if left untreated.
DCIS patients typically undergo a lumpectomy to remove the malignant cells, and between 17% and 40% currently undergo sentinel lymph node biopsies.
University of California-San Francisco professor of surgery and radiology Laura Esserman said: “Some surgeons say that sentinel node biopsies are no big deal, but I disagree. All interventions have consequences. More is not better. More is just more, and in this case, more is worse.”
The study compared the health outcomes of 5,957 women aged 67 to 94 who underwent a lumpectomy to remove DCIS. In total, 1,992 of them had undergone sentinel lymph node biopsy and 3,965 did not have the procedure. The women were followed for a median of 5.75 years after their initial lumpectomy.
Yale School of Public Health associate professor Shi-Yi Wang said: “Proponents of sentinel lymph node biopsy cite concerns that occult microinvasive disease within the DCIS may not be detected via other methods.
“Also, the sentinel lymph node biopsy is included in the Centers for Medicare & Medicaid merit-based incentive payment system for invasive breast cancer. This might create a financial incentive for providers to perform these biopsies even for non-invasive conditions.”
Wang acknowledged that the findings may not be generalizable to younger women and that further study is needed to determine if the procedure could benefit patients with high-risk DCIS.