349P - Risk of locoregional recurrence after mastectomy by hormone receptor status and HER2 status in breast cancer patients with 1-3 positive nodes

Date 27 September 2014
Event ESMO 2014
Session Poster Display session
Topics Biomarkers
Breast Cancer, Locally Advanced
Surgery and/or Radiotherapy of Cancer
Presenter Takashi Fujita
Citation Annals of Oncology (2014) 25 (suppl_4): iv110-iv115. 10.1093/annonc/mdu328
Authors T. Fujita1, M. Sawaki2, M. Hattori1, N. Kondou2, A. Yoshimura2, N. Gondou2, M. Ichikawa2, H. Kotani2, Y. Adachi2, T. Hisada2, J. Ishiguro2, H. Iwata1
  • 1Breast Oncology, Aichi Cancer Center, 464-8681 - Nagoya/JP
  • 2Breast Oncology, Aichi Cancer Center Hospital, Nagoya/JP

Abstract

Aim

The postmastectomy irradiation therapy (PMRT) was standard treatment for patients with more than four involved axillar lymph nodes. But patient with 1-3 positive axillar lymph nodes is controversial. To identify subgroups of patients with 1-3 positive axillar lymph nodes at significant risk of locoregional recurrence (LRR) who might furthermore benefit from the addition of PMRT.

Methods

We retrospectively analyzed the outcomes of 181 patients who had 1-3 positive nodes and treated with mastectomy without adjuvant irradiation between 2003 and 2008 in our hospital. Median follow-up time was 83.2 months. 156 (86.2%) patients received adjuvant chemotherapy (anthracycline alone: 29, anthracycline followed by taxane: 95, taxan alone: 10, CMF: 22 ). 76.9% (30/39) of the patients with HER2 positive cancer received trastuzumab and 92.3%(144/156) of the patients with hormone receptor positive cancer received hormone therapy. The median number of lymph nodes removed was 20. The rate of LRR and cause-specific survival were calculated by the Kaplan-Meier method, with comparisons among groups performed using log-rank tests.

Results

13 patients developed LRR as first events (local: 9, regional: 4). The 5-years and 10-years rates of LRR were 7.3 % and 8.6%, respectively. And the 5-years and 10-years rates of cause-specific survival were 95.1% and 91.7%, respectively. Furthermore, we analyzed the rates of LRR regard to subtype of tumor (ER+ group : ER+ and HER2-, HER2+ group: HER2+ and ER any, TN group: ER-and HER2-). The 5-year rates of LRR were 5.1%, 7.5%, and 24.5 % for patients with ER+ group, HER2+ group, TN group, respectively ( ER+ group vs TN group: p = 0.008, ER+ group vs HER2 group: p = 0.574 ). The 10-years rates of LRR were nearly identical among ER+ group and HER2+ group (7.0% vs 7.5%). The 5-years and 10-years rates of LRR were less than 10% for patients with any pathological tumor size.

Conclusions

Patients who had 1-3 positive axillar lymph node and TN subtype tumor experience the 5-year rate of LRR in excess of 20% and should be offered PMRT.

Disclosure

H. Iwata: Honoraria (Chugai Pharma, Hiroji Iwata). All other authors have declared no conflicts of interest.