Imaging Evaluation of the Axilla—A National Survey of Clinical Practice Among Radiologists

Objective To assess awareness and implementation of the American College of Surgeons Oncology Group Z0011 trial findings, approaches to axillary nodal imaging, and to identify differences in practice based on respondent characteristics. Methods An online survey was distributed to members of the Society of Breast Imaging. Questions regarded demographics, evaluation approaches, and impact of the Z0011 trial. Poisson regression with robust standard errors to regression was used to generate multivariable-adjusted relative risks and 95% confidence intervals (CIs) for associations. Results The response rate was 21.7% (430/2007). The majority (295/430, 68.6%) reported always performing axillary US in patients with a BI-RADS 4B, 4C, or 5 breast mass. Most respondents (299/430, 69.5%) were familiar with the findings of the Z0011 trial. Radiologists in academic practice were 0.67 (95% CI: 0.54–0.83) times less likely than private practice radiologists to perform axillary US in all masses and 1.31 (95% CI: 1.13–1.52) times more likely to be very familiar with the trial. Frequency of axillary US showed no association with time spent in breast imaging, years in practice, or presence of dedicated breast surgeons. Increased time in breast imaging and presence of dedicated breast surgeons was strongly associated with familiarity with the trial. No association was observed with years in practice. Most respondents (291/430, 67.7%) made little or no change to their practice based on trial findings. Conclusion There is wide variability in approaches to axillary nodal evaluation, demonstrating a need for improved education and guidelines for axillary imaging in breast cancer patients.

Impact of the ACOSOG Z0011 Trial on Surgical Practice in Asian Patients: Comparison of Trends in Axillary Surgery for Breast Cancer Between Korean and Dutch Cohorts

PurposeSince the publication of the Z0011 trial, practice-changing clinical guidelines for breast surgery have been developed. Although recent studies confirmed the feasibility of the Z0011 strategy in Asian populations, there has been no study on the trends of axillary surgery in Asian cohort. This study aimed to investigate the time trend of axillary surgery for breast cancer in Korea and compare it with that in Dutch cohort to understand the impact of the Z0011 trial.MethodsWe collected prospectively constructed data from the nationwide Korean Breast Cancer Registry (KBCR). We identified patients who underwent sentinel node biopsy followed by breast-conserving surgery from 2011 to 2018 and were found to have pathological stage T1-2N1-3M0 disease. Regression analyses were performed to compare the downward trend of axillary lymph node dissection (ALND) in our cohort with that previously reported in a Dutch cohort.Results From KBCR data, 7,478 patients met the inclusion criteria. The proportion of ALND significantly decreased from 2011 (76.6%) to 2018 (47.5%). Multivariate analysis revealed that earlier year at diagnosis, larger tumor size, and lymphatic invasion were associated with a higher odds ratio of performing ALND. Compared to Dutch cohort, the downward trend of ALND in Korea was significantly more gradual (annual percent change: 30.1% vs. 5.8%, P < 0.001).ConclusionsThis study demonstrated a downward trend of ALND in Korean patients with breast cancer. However, the rate of decrease was significantly slower than that in Dutch cohort, indicating the need to spread the Z0011 strategy in Asia.

Potential Impact of the Z0011 Trial on the Omission of Axillary Dissection: A Retrospective Cohort Study

Objective To evaluate the number of patients with early-stage breast cancer who could benefit from the omission of axillary surgery following the application of the Alliance for Clinical Trials in Oncology (ACOSOG) Z0011 trial criteria. Methods A retrospective cohort study conducted in the Hospital da Mulher da Universidade Estadual de Campinas. The study population included 384 women diagnosed with early-stage invasive breast cancer, clinically negative axilla, treated with breast-conserving surgery and sentinel lymph node biopsy, radiation therapy, chemotherapy and/or endocrine therapy, from January 2005 to December 2010. The ACOSOG Z0011 trial criteria were applied to this population and a statistical analysis was performed to make a comparison between populations. Results A total of 384 patients underwent breast-conserving surgery and sentinel lymph node biopsy. Of the total number of patients, 86 women underwent axillary lymph node dissection for metastatic sentinel lymph nodes (SNLs). One patient underwent axillary node dissection due to a suspicious SLN intraoperatively, thus, she was excluded from the study. Among these patients, 82/86 (95.3%) had one to two involved sentinel lymph nodes and met the criteria for the ACOSOG Z0011 trial with the omission of axillary lymph node dissection. Among the 82 eligible women, there were only 13 cases (15.9%) of lymphovascular invasion and 62 cases (75.6%) of tumors measuring up to 2 cm in diameter (T1). Conclusion The ACOSOG Z0011 trial criteria can be applied to a select group of SLN-positive patients, reducing the costs and morbidities of breast cancer surgery.