The Value of Ultrasound in Detecting Extra-Axillary Regional Node Involvement in Patients With Advanced Breast Cancer

Abstract

Abstract Learning Objectives After completing this course, the reader will be able to: Describe the ways in which regional ultrasound has contributed to more accurate staging in a population of locally advanced breast cancer patients.Explain how regional nodal information leads to changes in radiation therapy portals and total doses.Discuss the role of regional ultrasound in reflecting a truer level of disease burden in locally advanced breast cancer patients before therapies, including neoadjuvant chemotherapy, may limit knowledge of disease extent and consequently affect radiation treatment planning. CME This article is available for continuing medical education credit at CME.TheOncologist.com Assessment of the regional lymphatics is important for accurate staging and treatment of breast cancer patients. We sought to determine the role of regional ultrasound in providing clinically relevant information. We retrospectively analyzed data from patients who were treated curatively in 1996–2006 at The University of Texas MD Anderson Cancer Center for clinical stage III breast cancer. We compared differences in regional lymph node staging based on ultrasound versus mammography and physical examination in the 865 of 1,200 patients who had external-beam radiation as part of their treatment and regional ultrasound studies as part of their initial evaluation. Ultrasound uniquely identified additional lymph node involvement beyond the level I or II axilla in 37% of the patients (325 of 865), leading to a change in clinical nodal stage. Ninety-one percent of these abnormalities that could be biopsied (266 or 293) were confirmed to contain disease. The sites of additional regional nodal disease were: infraclavicular disease, 32% (275 of 865); supraclavicular disease, 16% (140 of 865); and internal mammary disease, 11% (98 of 865). All patients with involvement in the extra-axillary regional nodal basins received a radiation boost to the involved areas ≥10 Gy. Thus, over one third of patients with advanced breast cancer had their radiation plan altered by the ultrasound findings. Regional ultrasound evaluation in patients with advanced breast cancer commonly revealed abnormalities within and beyond the axilla, which changed the clinical stage of disease and the radiation treatment strategy. Therefore, regional ultrasound is beneficial in the initial staging evaluation for such patients.