Abstract 3093
Background
Tumor phenotype may change during breast cancer (BC) progression and discordance between primary and metastases ranges between 16% and 21% for Hormone Receptor (HR) expression in some series. The impact of this change on patient (pts) management and outcome is not yet clear, even though preliminary data indicate that the molecular characterization of recurrent breast cancer may induce clinicians to modify the treatment choice in ∼14% of the cases and that a change in the receptor status is associated with poorer survival. This analysis evaluates the prognostic impact of receptor discordance between paired primaries and recurrences.
Methods
We used data of 879 pts of the longitudinal cohort AMBRA study, identifying 3 different groups: Group A: HR+ BC remaining HR+ at relapse; Group BHR+ BC becoming TNBC; Group C:TNBC remaining TNBC. Change in HR status was evaluated on the biopsy done at the moment of relapse. Time to event was evaluated by Cox-Mantel Hazard Ratio and Logrank Test; Mean/median by Wilcoxon Rank-Sum Test.
Results
Pts who underwent biopsy at the time of relapse were 545/879 (62%), of those 462 (84.4%) were classified as Luminal tumors and 83 (15.2%) TNBC on primary. Change in tumor phenotype occurred in 31 (6.7%) of Luminal BC and 16 (19.3%) TNBC, probably due to a higher genomic instability (p = 0.021). Median DFS between Luminal BC was not different: HR+àHR+: 74.56 months (95%CI 66.8-82.1) vs HR+àTNBC: 89.73 months (95%CI:44.73-103.46). Table summarizes main data in time to event in the 3 identified groups. *PFS at 1strelapse; **PFS at 2nd relapse; ***Time to Treatment Change at 1strelapse; °OS at 1strelapse; §OS from 1stPDTable:
325P
HR+/HR + (range) Group A | HR+/TNBC (range) Group B | p value Group A vs C | TNBC/TNBC (range) Group C | |
---|---|---|---|---|
PFS1* (months) | 13.65 (0,77-162,03) | 9.45 (3,97-52,73) | 0.36 | 8.13 (6.3-10.9) |
PFS2** (months) | 6.83 (0,00-57,13) | 6.12 (2,67-26,30) | 0.84 | 4.20 (0,33-22,17) |
TTC1*** (months) | 12.43 (0,13-163,10) | 8.88 (0,00-48,40) | 0.50 | 7.88 (0,23-27,80) |
TTC2**** (months) | 7.45 (0,00-55,97) | 6.73 (3,77-26,80) | na | na |
OS1° (months) | 23.1 (20-26) | 15 (8.7-26.3) | 0.031 | 3.60 (0,60-25,38) |
OS (years) | 8.52 (0,26-115,92) | 7.86 (0,19-30,67) | 0.43 | 3.58 (2.91-2.39) |
OS from PD1§ (months) | 25.8 (0,00-207,53) | 17.23 (2,67-104,30) | 0.82 | 17.90 (2,37-53,57) |
Conclusions
Change in tumor phenotype has a significant impact on OS; BC pts who become TNBC at relapse should be treated in the same way as TNBC pts at diagnosis. Anyway, OS of Luminal BC who change phenotype seems to be better than TNBC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
GIM - Gruppo Italiano Mammella.
Funding
Celgene.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4250 - Phase II study of avelumab in combination with cetuximab as a rechallenge strategy in pre-treated RAS wild type metastatic colorectal cancer patients: CAVE (cetuximab-avelumab) Colon.
Presenter: Erika Martinelli
Session: Poster Display session 2
Resources:
Abstract
5234 - The ORCHESTRA trial; A phase III trial of adding tumor debulking to systemic therapy versus systemic therapy alone in multi-organ metastatic colorectal cancer (mCRC).
Presenter: Lotte Bakkerus
Session: Poster Display session 2
Resources:
Abstract
5294 - EMERGE: Epigenetic Modulation of the Immune Response in Gastrointestinal cancers
Presenter: Elizabeth Cartwright
Session: Poster Display session 2
Resources:
Abstract
913 - Phase III, international, multicenter, randomized, open-label trial of adjuvant nab-paclitaxel plus gemcitabine (nab-P/G) vs gemcitabine (G) alone for surgically resected pancreatic adenocarcinoma (APACT): subgroup analyses
Presenter: Margaret Tempero
Session: Poster Display session 2
Resources:
Abstract
1668 - FOLFIRINOX in locally advanced (LA) and borderline resectable (BR) pancreatic adenocarcinoma : update of the AGEO cohort.
Presenter: Edouard Auclin
Session: Poster Display session 2
Resources:
Abstract
2559 - Impact of adjuvant treatment with nab-paclitaxel and gemcitabine (nab-P+GEM) vs gemcitabine alone (GEM) on health-related quality of life (QoL) in patients (pts) with surgically resected pancreatic adenocarcinoma (PA) in the Adjuvant Pancreatic Adenocarcinoma Clinical Trial (APACT)
Presenter: Hanno Riess
Session: Poster Display session 2
Resources:
Abstract
4897 - Early detection of pancreatic ductal adenocarcinoma using methylation signatures in circulating tumor DNA
Presenter: Xiao-ding Liu
Session: Poster Display session 2
Resources:
Abstract
1755 - Evaluation of minimal important difference (MID) for the European Organisation for Research and Treatment of Cancer (EORTC) Pancreatic Cancer Module (PAN26) in patients with surgically resected pancreatic adenocarcinoma
Presenter: Michele Reni
Session: Poster Display session 2
Resources:
Abstract
2876 - Multispectral analysis of lymphocyte complexity in periampullary adenocarcinoma
Presenter: Sebastian Lundgren
Session: Poster Display session 2
Resources:
Abstract
1902 - Phase II trial of preoperative modified FOLFIRINOX (mFOLFIRINOX) followed by postoperative gemcitabine (GEM) in patients (pts) with borderline resectable (BR) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC)
Presenter: Jae Ho Jeong
Session: Poster Display session 2
Resources:
Abstract