Abstract P2-01-13: Can axillary lymph node clearance be avoided in women with node positive breast cancer receiving primary chemotherapy?

Abstract

Abstract Background For patients who receive primary chemotherapy for their early breast cancer the current practice for lymph node positive (LN) disease at presentation is in transition, with a drive towards sentinel LN biopsy (SLNB) rather than axillary node clearance (ANC) for patients who achieve a good response to primary chemotherapy. Boileau et al initially reported that approximately 30% of patients could potentially avoid clearance, but with a recommendation for further evaluation before including SLNB in guidelines for biopsy proven node-positive disease prior to primary chemotherapy for early breast cancer. Methods This was a retrospective single centre study. Examining the records of all patients who had received primary chemotherapy between January 2010 and October 2014. Patients were identified through the Guy's Breast Cancer Database and chemotherapy prescribing system. To fully assess the LN status, all patients were cross-referenced with the electronic notes on our electronic noting system (MOSAIQ), radiology on Patient Archiving and Communication System (PACS) and histology on our Electronic Patient Record (EPR). Results: 1526 patients were identified, of whom 156 underwent primary chemotherapy. 111 patients had suspicious nodes on imaging (ultrasound and/or MRI) and underwent LN biopsy. 69 patients had positive nodes pre-chemotherapy. 28 of these 69 patients (40.6%) had negative nodes at ANC, of these 14 (50%) had complete pathological complete response (pCR) in their primary tumour(s) of whom 12 (86%) had radiological CR prior to surgery. Of the 41 who remained positive only three achieved pCR of their primary tumour after chemotherapy. 22 patients were LN positive post primary chemotherapy, despite having been identified as initially LN negative. Of these 9 had a negative pre chemotherapy biopsy, and only 1 of these 22 patients had a pCR. Discussion: We have confirmed that ANC may be avoided in selected patients with LN involvement at presentation. In our series over 40% could have had SLNB instead. Factors supporting this approach include those patients who have an excellent radiological response to primary chemotherapy. Conversely, 22 of 87 (25%) had positive LN after chemotherapy having been initially thought to be LN negative at presentation, highlighting the possible need for multiple nodal sampling prior to chemotherapy as well as further nodal assessment after chemotherapy for complete staging. Citation Format: Chowdhury MHR, Thillai K, Lucey A, Michalarea V, Mera A, Karapanagiotou E, Sandri I, Mansi J. Can axillary lymph node clearance be avoided in women with node positive breast cancer receiving primary chemotherapy? [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-13.