The rate of breast cancer screening among breast cancer survivors declines over time.
Adherence to Guidelines for Breast Surveillance in Breast Cancer Survivors
Authors: Ruddy, K.J. et. al.
Source:J Natl Compr Canc Netw 2018;16(5):526-534
The standard recommendation for breast cancer screening among survivors is to resume annual mammograms one year following the mammogram that led to the cancer diagnosis. If a woman had lumpectomy and radiation, her next set of mammograms should be performed 6-12 months after her last treatment. Detection of breast cancer recurrence by mammography is associated with earlier disease stage and increased survival.
The investigators noted that many breast cancer survivors do not resume annual breast cancer screening. They observed a group of survivors for rates of screening mammography and magnetic resonance imaging (MRI) over time. Over 4700 women diagnosed with breast cancer between 2005 and 2015 were followed over a period of about 5 years. The rates of screening mammogram and MRI were recorded.
Interestingly, the number of women who had bilateral mastectomies rose over the observation period: 25.9% of women had the procedures in 2005 compared to 48.9% of women in 2015.
Just over 50% of all the women had screening mammograms all five years. During year 1, 86% were screened. This dropped to 80% by year 5. Women were less likely to undergo screening mammography as they became long-term survivors. Factors associated with this result were history of mastectomy, having more than 3 comorbidities and black ethnicity. For women over 65, having a visit to the oncologist or primary care provider increased the likelihood of getting mammograms.
Significantly fewer women had MRIs to begin with, and the numbers also declined over the studied time period (9% in year 1 and 7% by year 5). The researchers noted that the low numbers of MRIs were probably due to several factors. As more women chose bilateral mastectomies, the need for MRIs declined. MRIs have been shown to be of value for women with pathogenic BRCA mutations or strong family histories, but most breast cancer survivors do not meet these criteria. Also, a landmark study in 2010 did show that there was no surgical benefit to obtaining MRI at the time of breast cancer diagnosis, which would obviate its use after treatment completion. Furthermore, insurance guidelines may have played a part in the decline of MRI use.
This study demonstrated that breast cancer survivors may drop out of their breast cancer screening programs over time. As such surveillance provides significant benefits to survival, it is important to find ways to increase and maintain compliance among these patients.