Abstract P1-14-09: Long term survival of locally advanced breast cancers (LABC) treated with neoadjuvant treatment, results of a multicenter randomised phase II study (Remagus 02 trial)
Authors: Giacchetti S , Hamy-Petit A-S , Delaloge S , Brain E , Berger F , Mathieu M-C , de Cremoux P , Bertheau P , Guinebretière J-M , Saghatchian M , Tembo O , Marty M , Pierga J-Y 
Published: May 2016

Backgound : The primary analysis of the REMAGUS-02 multicenter randomized phase II trial demonstrated that celecoxib did not improve pCR rates in pts with HER2-negative localized invasive breast cancer (BC), whereas trastuzumab increased pCR rates in HER2-positive ones [Pierga BCRT 2010]. We report here the long-term follow-up results of this trial for disease free survival (DFS) and overall survival (OS).

Patients and methods: From May 2004 to October 2007, 340 stage II-III BC patients were randomly assigned to receive 4 cycles (c) of epirubicin–cyclophosphamide q 3 w followed by 4 c of docetaxel q 3 w +/- trastuzumab in HER2 positive pts (120 pts) or +/- celecoxib in HER2 negative pts (n=220). From September 2005, all pts with HER2 positive BC received adjuvant T for a total of 18 c (n=106). Patients with hormone receptors (HR) positive tumor received adjuvant endocrine treatment according to menopausal status

Results: With a median follow up of nearly 8 years (94.4 months, 20-127m), 112 relapses and 75 deaths have been observed (median DFS and OS not reached). Eight years DFS and OS were respectively 63 % [57%-71%] and 75 % [70%-81%] in HER2 negative group; and 75% [67%-83%] and 82 % [74%-90%] in HER2 positive group. DFS was significantly higher in HER+ pts than in HER2-(HR: 0.64 [0.42-0.99], p=0.042), whereas OS did not differ significantly (HR: 0.67, [0.41-1.11], p=0.123).

In the overall population, progesterone receptor (PgR) positivity was associated with a better DFS (p=0.012) and OS (p&lt;0.001) as compared to ER+/PgR- (DFS: HR=2.07 [1.27-3.39]; OS: HR=2.53 [1.3-4.92]) and ER-/PR-; DFS: HR=1.56 [0.98-2.46]; OS: HR: 3.34 [1.87 – 5.97]. In the ER-/PR- group, DFS reached a "plateau" after three years follow-up, while the annual risk of relapse remained constant in the ER+/PR- subgroup.

In the HER2- subgroup, no effect of neoadjuvant celocoxib was observed on survival, neither in intention to treat (ITT) nor in per protocol analyses. In the multivariate analysis clinical stage (T3/T4 versus T2, HR: 1.92 [1.209 - 3.05], p=0.006), PgR status (positive versus negative HR : 0.52, [0.32-0.84], p=0.007) and pCR (yes vs no, HR : 0.213 [0.066-0.687], p=0.01) were significant predictors of DFS.

In the HER2+ subgroup, neoadjuvant versus adjuvant trastuzumab was not significantly associated with DFS, neither in the ITT, nor in the per protocol analysis.

Conclusion: Celecoxib was not associated with pCR or survival benefit when added to conventional neoadjuvant CT in Her2-negative BC pts. Lack of PgR expression is a major prognostic factor for survival. Neoadjuvant versus adjuvant trastuzumab increased pCR rates but did not change significantly DFS and OS of HER2 positive BC pts.

Citation Format: Giacchetti S, Hamy-Petit A-S, Delaloge S, Brain E, Berger F, Mathieu M-C, de Cremoux P, Bertheau P, Guinebretière J-M, Saghatchian M, Tembo O, Marty M, Pierga J-Y. Long term survival of locally advanced breast cancers (LABC) treated with neoadjuvant treatment, results of a multicenter randomised phase II study (Remagus 02 trial). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-09.