When used for screening, the cancer detected by breast MRI tends to be at an earlier stage than by mammography (MA). Many high-risk surveillance clinics adopt a schedule of annual MA and annual MRI, alternating every 6 months, assuming an interval cancer between annual screening of one imaging method may be picked up by the other method. However, benefit has not been proven for such practice. When advanced screening is initiated for a woman newly discovered for a germline high-risk mutation (i.e. pathogenic variant, PV), many providers start with a baseline MA, followed by a MRI 6 months after. However, many women discover their high-risk status at a much later age than the recommended age to start MRI screening. For example, the first MRI should start at age 25 for BRCA1 PV carriers. When a 45-year-old woman found out she carries a BRCA1 PV, delaying the MRI 6 months may delay the diagnosis of a breast lesion undetectable by the MA. We conducted a retrospective chart review in all women visited Moffitt Cancer Center (MCC) GeneHome (GH) high risk surveillance clinic from 3/2017 to 3/2021. The screening schedule in GH follows the guidelines published by National Comprehensive Cancer Network: annual screening MA and MRI for women carrying PVs conferring moderate or high risk for breast cancer. Such enhanced screening is also used for women whose lifetime breast cancer risk is 20% or higher based on the Tyrer-Cuzick model. We reviewed the records of 359 women carrying PVs in ATM, BRCA1, BRCA2, CHEK2, CDH1, NF1, PALB2, PTEN, STK11 and TP53, as well as 93 women carrying a PV in Lynch syndrome genes. In this period, 70 women underwent breast biopsy indicated by breast imaging, 10 had biopsy twice, 3 had biopsy trice. Breast cancer was detected in 16 individuals, premalignant lesions were detected in 3 individuals. Thirteen cases were primary breast cancer, 3 were recurrent breast cancer. Five cases were detected by their first screening MRI, 4 of the 5 were detected within the first month after the initial presentation at GH clinic. At the time of cancer detection, four women were at least 10 years older than the recommended age to begin screening MRI based on the genetic risk. One woman, a BRCA1 PV carrier, was 3 years older (28 yro) than the recommended age to start MRI (25 yro). Base on this observation, some breast cancer diagnosis may be delayed for up to 5 months in high-risk women if the first MRI is scheduled 6 months after the discovery of genetic risk.
BPI22-025 Figure 1. Female carrying PVs in Breast Cancer Risk Genes N=359
Citation: Journal of the National Comprehensive Cancer Network 20, 3.5; 10.6004/jnccn.2021.7290
