Are baseline ultrasound and mammographic features associated with rates of pathological completes response in patients receiving neoadjuvant chemotherapy for breast cancer?

Abstract

Background Increasing numbers of breast cancer patients receive neoadjuvant chemotherapy (NACT). We seek to investigate whether baseline mammographic and ultrasound features are associated with complete pathological response (pCR) after NACT. Methods A database of NACT patients was reviewed. Baseline imaging parameters assessed were ultrasound: posterior effect; echo pattern; margin and lesion diameter; mammography: spiculation and microcalcification. Core biopsy grade and immunophenotype were documented. Data were analysed for the whole study group and by immunophenotype. Results Of the 222 cancers, 83 (37%) were triple negative (TN), 61 (27%) ER positive/HER-2 negative and 78 (35%) HER-2 positive. A pCR occurred in 46 of 222 cancers (21%). For the whole group, response was associated with high core biopsy grade (grade 3 vs. grade 1 or 2) (26% vs. 9%, p = 0.0044), absence of posterior shadowing on ultrasound (26% vs. 10%, p < 0.001) and the absence of mammographic spiculation (26 vs. 6%, p < 0.001). Within the HER-2 positive group; the absence of shadowing and spiculation remained highly associated with pCR, in addition to small ultrasound size (AUC = 0.71, p < 0.001) and the absence of microcalcification (39% vs. 21%, p < 0.02). On multivariable analysis absence of spiculation and core grade remained significant for the whole cohort, size and absence of spiculation remained significant for HER-2 positive tumours. No feature predicted pCR in TN tumours. Conclusion A pCR is less likely when there is mammographic spiculation. Small ultrasound size is associated with pCR in HER-2 positive tumours. These findings may be helpful when discussing NACT and surgical options with patients. Trial registration UK Clinical Trials Gateway: registration number 16712.

Early ultrasound evaluation identifies excellent responders to neoadjuvant systemic therapy among patients with triple‐negative breast cancer

“…More complex assessments using shear-wave US for TNBC have failed to demonstrate a benefit beyond the use of grayscale US employed here. [33][34][35] Although breast MRI has been proposed to be the imaging modality of choice for the early evaluation of early treatment responses to NAST, the use of MRI for this purpose in clinical practice has been limited because of the lack of consistency and standardization of specific MRI parameters that hold greater potential for early prediction of a pCR to NAST and the cost and the complexity of breast MRI. [36][37][38] In contrast, conventional breast US is widely accessible, and this can facilitate the implementation of serial US examinations to monitor treatment response.…”

The Diagnostic Performance of Minimally Invasive Biopsy in Predicting Breast Pathological Complete Response After Neoadjuvant Systemic Therapy in Breast Cancer: A Meta-Analysis

“…Multiple studies evaluated the reliability of imaging approaches, including ultrasound, mammography, and MRI, in predicting breast pCR after NST. However, the accuracy of these techniques was far from satisfactory (12)(13)(14)(15)(16)(17). Some early studies reported that using radiotherapy alone (without breast surgery) as the local treatment approach for breast cancer patients with cCR on imaging will lead to much higher rates of relapses (31)(32)(33).…”

“…Some studies focus on the accuracy and reliability of non-invasive imaging methods to predict breast pCR, but the results are far from satisfactory. Neither ultrasound nor mammography is reliable with false negative rates (FNR) ranging from 9 to 70% ( 12 – 14 ). Similarly, magnetic resonance imaging (MRI) demonstrated an FNR up to 30–50% in predicting breast residual tumor after NST ( 15 – 17 ).…”

Current Landscape of Breast Cancer Imaging and Potential Quantitative Imaging Markers of Response in ER-Positive Breast Cancers Treated with Neoadjuvant Therapy

“…Mammography together with breast ultrasound (US) has been used to measure residual tumor burden during neoadjuvant therapy. While the resolution of some baseline mammographic features such as microcalcifications and spiculation of masses are associated with response [38], the use of mammography may be of limited value during neoadjuvant therapy due to variable accuracy and sensitivity to changes in residual tumor burden [39].…”

“…In a study of 159 patients, the percent change in US-measured tumor size at mid-treatment was linearly associated with the RCB index score in triple-negative (TN) and hormonal positive (HR+; ER or progesterone (PR) receptor positive or both) subtypes, but not in HER2+ tumors [ 59 ]. US imaging features such as the absence of posterior acoustic shadowing and spiculation were significant predictors of pCR in HER2+ tumors [ 38 ]. On the other hand, no feature was found to associate with response in the TN subtype, and the presence of posterior shadowing was associated with HR+/HER2− breast cancers [ 60 ].…”