Axillary Staging With Supine 18f-Fdg Pet/Ct Is Useful In Breast Cancer Patients Undergoing Tailored Axillary Treatment After Neoadjuvant Systemic Therapy According To The Mari Protocol

Background: Staging in breast cancer patients can be performed with FDG-PET/CT in supine position. At the NKI, a prone position scan is added to the supine scan protocol to improve visualization of FDG-uptake in the breast. In clinically node-positive (cN+) patients with neoadjuvant systemic therapy (NST), the number of FDG-positive axillary lymph nodes (ALNs) on PET/CT pre-NST (cN < 4 or cN ≥ 4) in combination with the MARI procedure (Marking Axillary lymph nodes with Radioactive Iodine seeds) is used to tailor axillary treatment post-NST. It is unclear however whether the use of prone scanning compared to supine scanning affects the adjuvant axillary treatment strategy.