Primary tumour response on breast MRI as a predictor of axillary pathologic response in breast cancer patients treated with neoadjuvant chemotherapy - Report - MDSpire
Advertisement
Primary tumour response on breast MRI as a predictor of axillary pathologic response in breast cancer patients treated with neoadjuvant chemotherapy
Breast MRI Primary Tumour Response Predicts Axillary Pathologic Response Post-NACT
Overview
This study evaluated whether breast radiologic complete response (rCR) on MRI after neoadjuvant chemotherapy (NACT) can predict axillary pathological complete response (ypN0) in breast cancer patients. Findings suggest breast rCR is a useful preoperative indicator of axillary nodal status, especially in clinically node-negative and estrogen receptor-negative subgroups.
Background
Neoadjuvant chemotherapy (NACT) is increasingly used in breast cancer to downstage tumors before surgery. Breast MRI is the most accurate imaging modality to assess primary tumor response, with complete disappearance termed breast radiologic complete response (rCR). Accurate prediction of axillary lymph node response is critical for tailoring axillary surgery, but MRI assessment of axillary nodes is limited by technical factors. Pathologic complete response in breast and axilla (ypT0 and ypN0) correlates with improved survival outcomes. This study investigates if breast MRI response can serve as a surrogate for axillary pathological response preoperatively.
Data Highlights
Patient Subgroup
ypN0 Rate After NACT (%)
Clinically node-negative (cN0)
81.1
Clinically node-positive (cN+)
36.6
HR+/HER2- (cN+)
18
HR+/HER2+ (cN+)
45
HR-/HER2+ (cN+)
60
Triple-negative (cN+)
48
Key Findings
Breast radiologic complete response (rCR) on MRI is defined by absence of residual malignancy or enhancement post-NACT.
Breast rCR correlates strongly with pathologic complete response in the axilla (ypN0), especially in clinically node-negative patients.
Axillary MRI assessment is limited by incomplete visualization and protocol variability, reducing its reliability for nodal response evaluation.
Probability of ypN0 varies by clinical nodal status and breast cancer subtype, with higher rates in cN0 and ER-negative patients.
Breast MRI response may guide de-escalation of axillary surgery in select patient subgroups with high likelihood of nodal clearance.
Clinical Implications
Breast MRI assessment of primary tumor response after NACT can serve as a non-invasive tool to predict axillary nodal status preoperatively, potentially reducing the need for extensive axillary surgery in patients with breast rCR. This approach is particularly useful in clinically node-negative and ER-negative breast cancer patients, aiding personalized surgical planning and minimizing morbidity.
Conclusion
Breast radiologic complete response on MRI after neoadjuvant chemotherapy is a valuable predictor of axillary pathological response, supporting its role in guiding axillary treatment decisions. Incorporating breast MRI findings into clinical algorithms may optimize patient selection for axillary de-escalation strategies.
References
de Wild et al 2022 -- Axillary nodal response rates after NACT
American College of Radiology BI-RADS 2013 -- Breast Imaging Reporting and Data System
Dutch National Guidelines 2020 -- Breast Cancer Receptor Status Assessment
by Florien J. G. van Amstel, Rik G. M. van Mierlo, Patty J. Nelemans, Sanne M. E. Engelen, Janneke Houwers, Loes F. S. Kooreman, Vivianne C. G. Tjan-Heijnen, Sabine Siesling, Marjolein L. Smidt, Thiemo J. A. van Nijnatten
