USA: A recent study found that evidence is insufficient to support semi-annual mammography in the early postoperative period after breast-conserving surgery (BCS) in patients treated with neoadjuvant therapy (NAT), and annual mammography with the clinical exam is likely sufficient.
"Annual mammography with a clinical exam rather than semiannual is likely sufficient for women who have undergone breast-conserving surgery and were treated with NAT," the researchers wrote in Surgical Oncology Insight. Less than 2% of women developed locoregional recurrence on routine surveillance.

They added, "Semiannual mammography is associated with unnecessary benign biopsies, which may raise health care costs and patient distress."
Guidelines recommend annual mammography for most women following BCS for invasive breast cancer (IBC). However, for patients treated with BCS after neoadjuvant therapy, the optimal frequency for surveillance has not been established. Therefore, Farin Amersi, Cedars-Sinai Medical Center, Department of Surgery, Los Angeles, CA, USA, and colleagues aimed to assess the efficacy of semi-annual mammography after BCS in patients treated with NAT.
For this purpose, the investigators analyzed an institutional database of patients with IBC (cT1-T4, N0-N3, M0) who received BCS following NAT from 2007-2020. Surveillance imaging, clinicopathologic features, and outcomes were analyzed. Direct costs associated with surveillance were estimated based on Medicare Physician Fees.
The researchers reported the following findings:
· 139 patients received BCS following NAT, of which 42.4% had a pathologic complete response.
· Most patients received semi-annual mammography for 24 months post-operatively (84.2%, 82.0%, 80.0%, and 78.0% of patients received a mammogram at 6, 12, 18, and 24 months, respectively).
· Biopsies were performed due to abnormal imaging findings in 6.5%, 5.3%, 1.5%, and 6.3% of patients at 6, 12, 18, and 24 months, respectively. Overall, 77.8% of biopsies performed were benign.
· At a median follow-up of 65 months, 15.8% of patients developed recurrences, of which 63.6% were distant and 36.4% were locoregional.
· Only 1.4% of patients had a recurrence detected by mammographic surveillance.
· The additional direct costs associated with semi-annual imaging were $373.68 per patient.
The results point to these women being unlikely to benefit from more frequent mammographic surveillance. They added that shifting these women from semi-annual to annual mammography may reduce unnecessary biopsies and follow-up imaging from false-positive cases.
“As more patients receive NAT and pathologic complete response rates continue to improve, it will be vitally important to determine an evidence-based surveillance strategy for detecting locoregional recurrences promptly in women who receive breast-conserving surgery,” they concluded.
Reference:
DOI:https://doi.org/10.1016/j.soi.2024.100037