Abstract P1-01-06: How Often Does a Positive Sentinel Lymph Node Biopsy Prompt an Isolated Delayed Axillary Lymph Node Dissection?
Authors: JR Benson, GC Wishart, P Forouhi, EN. Provenzano
Journal: Cancer Research (2010)

Abstract Background: Intra-operative nodal assessment can avoid delayed axillary lymph node dissection (ALND) in a proportion of sentinel lymph node biopsy (SLNB) patients. Several different methods are currently being practiced with no single one perceived as optimal in terms of performance, patient care, logistics and cost. Both frozen section and imprint cytology are inconsistent and of variable sensitivity compared to paraffin embedded H&amp;E sections and have not yet been surpassed by molecular assays based on reverse-transcription technologies. Modern approaches to axillary management can contribute to reduction in absolute numbers of isolated completion ALND cases without intra-operative nodal assessment. Methods: A retrospective analysis was undertaken of 549 consecutive patients involving a total of 550 non-invasive (extensive or localised ductal carcinoma in situ with mass lesion) and invasive tumours measuring &amp;lt;5cm in maximum radiological size with clinically negative nodes (1 bilateral case). This group of patients were all eligible for SLNB according to unit guidelines. Those patients having SLNB before neoadjuvant therapy (32) or immediate breast reconstruction (IBR) (56) were excluded from further analysis together with 23 patients undergoing single stage axillary surgery (level I/II ALND) due to advanced age or co-morbidity. The remaining 438 patients were potentially liable for an isolated delayed completion ALND consequent to a positive SLNB. Most of these (84%) had an axillary ultrasound examination (368/438) with 58 proceeding directly to ALND based on positive nodal core biopsy (49), suspicious nodes with (6) or without (3) a negative biopsy. Results: Amongst 381 cases of SLNB, 87 were node positive (22.8%) and proceded to completion ALND. Just over half of these had an isolated delayed ALND (50), whilst 37 patients had ALND combined with an additional surgical procedure (cavity re-excision; mastectomy with or without IBR). The recall rate for isolated ALND was 9.1% (50/549) when calculated as a percentage of all patients initially eligible for SLNB and 11.4% when the denominator was the number of tumours suitable for primary surgical treatment with SLNB or ALND based on axillary ultrasound (50/439). Within the authors’ practice, this represents a caseload for each surgeon of about 7 per annum. Conclusion: Intra-operative node assessment may be more difficult to justify for all SLNB patients in the context of contemporary practices. A significant proportion of patients are either deselected for SLNB by axillary ultrasound (approximately one-third of node positive patients overall) or can have completion ALND performed alongside definitive or additional breast surgery. Intra-operative analysis may further reduce these low recall rates for isolated ALND but may not be cost-effective nor logistically feasible within many healthcare systems. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-06.