14P - Does Z0011 trial changed our clinical practice in patients with metastases in sentinel lymph node (SNB).

Date 04 May 2017
Event IMPAKT 2017
Session Welcome reception and Poster Walk
Topics Breast Cancer
Surgical oncology
Therapy
Radiation oncology
Presenter Maria Nagadowska
Authors M.M. Nagadowska1, Z. Mentrak1, W. Michalski2, J. Piechocki1, Z. Nowecki1
  • 1Breast Cancer And Reconstructive Surgery Department, Maria Skłodowska-Curie Cancer Center and Institute of Oncology, 02782 - Warsaw/PL
  • 2Biostatistics, maria Skłodowska-Curie Cancer Center and Institute of Oncology, 02782 - Warsaw/PL

Abstract

Body

Background. Despite the progress in research of the breast cancer, lymph node status still remains the main prognostic parameter and the key factor for adjuvant therapy. The Z0011 trial initiated a paradigm shift in the treatment of axillary node positive breast cancer and thereafter in patients with involved sentinel lymph node ALND can be avoided. The purpose of this study was to compare the results of ALND in the group of patients treated in 2011 and 2015 and determine the risk of non sentinel node metastases.

Methods. A single institution retrospective study regarding the results of ALND in the sentinel lymph node positive cases treated in 2011 and 2015.

Out of 517 patients treated in 2011 for breast cancer stage I/IIA, 82 (15.8%) underwent ALND after sentinel lymph node biopsy (77 patients were finally analysed). Out of 725 patients treated for breast cancer in 2015, in 92 (12%) ALND was performed after SNB and 86 were available for analysis.

For the whole ALND group (n=163) logistic regression model was used to analyse the associations of node positivity in ALND with breast cancer biology.

Results. Out of 77 cases of ALND performed in 2011 in 52(67.5%) sentinel node was the only metastases found whereas in 2015 the same was noted in 42 patients (48.8%). There were differences between group: more patients treated in 2015 were in stage II (42 vs 19%), more PGR(-) (43 vs 8.8%) and in indications for ALND: in 2011 more patients underwent ALND for micro metastases (7.8 vs 1.1%).

The multivariable analysis indicated type of SNB metastases (micro vs macro), size of macro metastases, extra capsule invasion and PGR(-) status as the independent positive predictors of non sentinel metastases in ALND group. Moreover, we found on the border of significance that in 2015 chance for non sentinel node metastases was twice as big as in 2011 (chance quotient 2.033, p 0.054).

Conclusion. After starting to use the Zoo11 criteria in 2015 we noted the decreased rate of ALND and almost complete omission of ALND in cases with micro metastases in SNB. In our study the main risk factor for non sentinel lymph node involvement were type of SNB metastases (micro vs macro), size of macro metastases, extra capsule invasion and PGR(-) status in the primary tumour.

Clinical trial identification