P3-07-01: Are the Findings of ASOCOG Z0011 Applicable to District General Hospital Breast Unit – And How Should They Change Our Practice?

Abstract

Background: There has been considerable debate on the management of the axilla in breast cancer patients with lymph node metastasis found on sentinel lymph node biopsy (SLNB) following publication of the ACOSOG Z0011 study. This study conclude that axillary lymph node dissection (ALND) does not add any benefit to overall and disease free survival in some patients with positive SLNB. However it is not know if the patient characteristics of this study are transferable to other settings. A previous UK study has suggested that only a minority of patients from an academic specialist centre fit the ASOCOG Z0011 criteria and that the patient populations may not be comparable. The aim of our study was to assess the applicability of the Z0011 study to our patient population of a large District General Hospital in the UK and to what extent it should influence our practice. Methods: The Z0011 eligibility criteria for inclusion in analysis were applied to all patients undergoing SLNB for invasive cancer at West Hertfordshire Breast Unit from 2007–2011. These were: no neo-adjuvant chemotherapy, clinical T1 and T2 tumours, breast conserving surgery followed by whole breast radiotherapy and 1–3 positive nodes on SLNB. Patent characteristics and results were compared using fisher's exact test. Results: In our unit a total of 434 patients underwent SNLB of whom 64(14.7%) met the inclusion criteria of Z0011. Our patient population was comparable to that of Z0011 with regards to lymphovascular invasion, proportion of patients with micro-metastases and those with additional lymph nodes found on completion ALND. Our patients had significantly more T2 tumours. The only other statistically significant difference was in the proportion of estrogen receptor(ER) and progestrogen receptor (PR) positivity. Conclusion: Only a small proportion (14%) of patients undergoing SNLB in our patient population fit the criteria for Z0011. This was a higher proportion than in the previous UK study of this type. Similar to this study we found the proportion of patients with T2 tumours were greater in our patient population compared to Z0011. This is most likely a reflection of this unit not being a screening centre and brings in to question the international generalisability of Z0011. However the only other significant difference in our patients was a lower risk profile in terms of hormone rector positivity with more ER/PR positive and fewer ER/PR negative patients. The implications of Z0011, will in our practice, not make a significant difference to the rate of ANLD. We are however considering changing our patient management based on the result of Z0011 and this current study of our population, to offer no further axillary surgery to patients over 50 with T1 and ER/PR positive tumours who otherwise fit the Z0011 protocol. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-07-01.

Different outcome in node-positive breast cancer patients found by axillary ultrasound or sentinel node procedure

“…The Z0011 demonstrated that in patients with T 1–2 invasive breast cancer treated with breast-conserving therapy, including radiotherapy, and two or less positive sentinel nodes, the ALND could be omitted without affecting the prognosis [ 12 ]. However, some doubts were raised regarding the applicability of these Z0011 criteria in general practice, since this trial only included a selected group of node-positive patients detected by the SLNB [ 27 , 28 ]. Multiple studies have shown a large variability in the proportion of patients who fulfill the inclusion criteria of the Z0011 trial, ranging from 9 to 75% [ 29 – 32 ].…”

San Antonio Breast Cancer Symposium 2011 (SABCS) : quelle place va-t-il rester au curage axillaire ?

“…Olsen et al ont ainsi montré dans une sé rie de 434 patientes (T1-T2N0) avec un à trois GS mé tastatiques ayant eu un traitement conservateur du sein associé à une radiothé rapie du sein, que seulement 15 % de ses patientes issues d'un centre hospitalier au Royaume-Uni é taient comparables à celles incluses dans l'é tude amé ricaine de Giuliano [7]. De même, Chalmers et al [8] dans une sé rie de 94 patientes GS+ avec CA systé matique ont observé que 71 % d'entres elles n'auraient pas bé né ficié d'un CA complé mentaire selon les critè res d'inclusion de l'ACOSOG-Z0011.…”