Clinical TrialLong-term outcome of the REMAGUS 02 trial, a multicenter randomised phase II trial in locally advanced breast cancer patients treated with neoadjuvant chemotherapy with or without celecoxib or trastuzumab according to HER2 status

•Celecoxib, an anti Cox2, does not improve pathological complete response (pCR) nor outcome in HER2 negative breast cancer patients receiving sequential neoadjuvant chemotherapy.•Long term outcome of luminal B breast cancer can be worse than triple negative breast cancer while HER2 positive breast cancer patients have a better prognostic than other subtypes with the addition of trastuzumab in neoadjuvant or adjuvant setting.

BackgroundThe REMAGUS-02 multicenter randomised phase II trial showed that the addition to neoadjuvant chemotherapy (NAC) of trastuzumab in patients with localised HER2-positive breast cancer (BC) increased the pathological complete response (pCR) rate and that the addition of celecoxib in HER2-negative cases did not increase the pCR rate. We report here the long-term follow-up results for disease-free survival (DFS) and overall survival (OS).Patients and methodsFrom 2004 to 2007, 340 stage II-III BC patients were randomly assigned to receive neoadjuvant EC-T (four cycles of epirubicin-cyclophosphamide followed by four cycles of docetaxel) +/− celecoxib in HER2-negative cases (n = 220) and ± trastuzumab in HER2-positive cases (n = 120). From September 2005, all patients with HER2-positive BC received adjuvant T (n = 106).ResultsMedian follow-up was nearly 8 years (94.4 months, 20-127 m). In the HER2-negative subgroup, addition of celecoxib was not associated with a DFS benefit. Favourable factors were smaller tumour size, expression of progesterone receptor status (PgR) and pCR. In the HER2-positive population, neoadjuvant trastuzumab was not associated with a DFS benefit. Axillary pCR was the only prognostic factor associated with DFS in this group [HR = 0.44, 95% CI = 0.2-0.97], p = 0.035]. To note, DFS and OS were significantly higher in the HER2-positive than in HER2-negative BC patients (HR = 0.58 [0.36-0.92], p = 0.021).ConclusionCelecoxib combined with NAC provided neither pCR nor survival benefit in patients with HER2-negative BC. Absence of PgR is a major prognostic factor. Neoadjuvant trastuzumab increased pCR rates without translation into a DFS or OS benefit compared with adjuvant trastuzumab only. Axillary pCR could be a more relevant surrogate of survival than in the breast in HER2-positive population. A retrospective comparison shows that patients with HER2-positive tumours have a better outcome than HER2-negative BC patients showing the impact of trastuzumab on the natural history of BC.