Abstract 5327
Background
Pathologic complete response (pCR) is a surrogate marker of a better relapse-free (RFS) and overall survival (OS), particularly in HER2 overexpressing and triple-negative breast cancer (TNBC) subtypes. Our aim is to assess the impact of HER2 expression level on pCR, in patients with luminal or TNBC treated with neoadjuvant chemotherapy (NAC).
Methods
We conducted a retrospective analysis in luminal and TN non-metastatic breast cancer patients, addressed to cancer center Georges François Leclerc in Dijon for NAC. Hormone receptor and HER2 expression were centrally assessed according to CAP/ASCO criteria. The pathologic response was dichotomized in pCR and non-pCR and evaluated according to Chevalier classification.
Results
Between 2007 and 2018, 761 patients (pts) were recorded, of which 263 (34.5%) had TNBC and 498 (65.5%) luminal-HER2 negative BC. Among TNBC, 189 pts (70.8%), 54 pts (20.2%) and 24 pts (8.9%) had respectively score 0, 1 and 2, and negative FISH. In luminal tumors these results were respectively 246 (49.3%), 181 (36.3%) and 21 (4.2%). Median age, size of primary tumour and lymph node involvement were similar in both subpopulations. Regarding NAC, 20.9% received only taxanes, 22.1% only anthracyclines and 55.1% both agents. The combination was more often recommended in TNBC 74.2% vs 59.3% (p = 0.03). pCR rate in the primary tumour and lymph nodes was 29% (157 pts) in the whole cohort. This rate varied according to HER2 expression (0, 1+, 2+) from respectively 48.6% (51pts), 36.4% (8pts) and 28.6% (4pts) (p = 0.256) in TNBC and from 8.5% (7pts), 5.3% (5pts) and 4.1% (2pts) (p = 0.532) among luminal tumors. Both OS and RFS were associated with a good Chevalier pathologic response (p < 0.001) in TNBC but not in luminal tumours (p = 0.5257 and p = 0.9845). Neither pCR, nor the Chevalier response was statistically correlated with HER2 score.
Conclusions
No correlation between pCR and the level of HER 2 expression was found neither in luminal nor in TNBC patients. In TNBC patients, differences in terms of pCR were noticed between the 3 HER expression groups. The predictive role of HER2 expression should be further explored in early localized TNBC in a larger population.
Clinical trial identification
Editorial acknowledgement
Isabel Gregoire, medical writer, Department of Biostatistics Georges Francois Leclerc Cancer Center, Dijon, France.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3139 - Efficacy and safety of FOLFIRI/Aflibercept (FA) in elderly population with mCRC after failure of oxaliplatin-based chemotherapy.
Presenter: Nieves Martinez Lago
Session: Poster Display session 2
Resources:
Abstract
3446 - Fluoropyrimidine-induced cardiotoxicity in colorectal cancer patients: preliminary data from the prospective observational CHECKPOINT trial (NCT02665312)
Presenter: Pasquale Lombardi
Session: Poster Display session 2
Resources:
Abstract
3969 - Comparable survival outcome between Thai patients with sporadic young adult and adult onset colorectal cancer
Presenter: Kanjana Sukhokanjanachusak
Session: Poster Display session 2
Resources:
Abstract
4455 - Impact of primary tumor side on 3-year survival outcomes of first-line (1L) FOLFOX-4 ± cetuximab in patients with RAS wild-type (wt) metastatic colorectal cancer (mCRC) in the phase 3 TAILOR trial
Presenter: Shukui Qin
Session: Poster Display session 2
Resources:
Abstract
4481 - Undetectable RAS mutant clones in plasma: possible implication for therapy and prognosis in the patient with RAS mutant metastatic colorectal cancer?
Presenter: Mohamed Bouchahda
Session: Poster Display session 2
Resources:
Abstract
5074 - Dihydropyrimidine dehydrogenase (DPD) determination prior the administration of medicines containing fluorouracil: a single Spanish hospital experience.
Presenter: Maria Dolores Mediano Rambla
Session: Poster Display session 2
Resources:
Abstract
5242 - Differences in survival between right and left-sided colorrectal cancer (CRC) in every stage, a CARESS-CCR Group Study.
Presenter: Julia Alcaide-Garcia
Session: Poster Display session 2
Resources:
Abstract
1123 - Quality of Life (QoL) in patients with aflibercept (AFL) and FOLFIRI for metastatic colorectal cancer (mCRC) – Interim analysis with focus on mutational status of the non-interventional study QoLiTrap (AIO-LQ-0113)
Presenter: Roger von Moos
Session: Poster Display session 2
Resources:
Abstract
1212 - The cost of adverse event management in patients with RAS wild-type metastatic colorectal cancer treated with first-line cetuximab and panitumumab: an Italian healthcare payer perspective
Presenter: Karl Patterson
Session: Poster Display session 2
Resources:
Abstract
1619 - Meta-analysis of KRAS Mutation as prognostic factor in patients (pts.) with resection of colorectal (CRC) liver metastases: Tumor burden and Sideness analysis.
Presenter: Maria Romina Luca
Session: Poster Display session 2
Resources:
Abstract