Abstract 4359
Background
The prognostic role of Progesterone receptor (PR) expression in early invasive breast cancer (BC) remains controversial. The aim of this retrospective analysis was to investigate the impact of PR expression levels on outcome of patients with luminal-like Her2 negative early BC.
Methods
A population cohort of 441 primary invasive ER+/Her2- early BC patients from a single cancer center underwent surgery and received adjuvant endocrine therapy from 2000 to 2017 was retrieved. To assess the impact of the different PR levels on the prognosis, we calculated the Distant Free Survival (DFS) and the Breast Cancer Specific Survival (BCSS) according to 4 subtypes established on the basis of Ki67 value and PR expression rate (Subtype 1: PR ≥ 20%/Ki67<20%; Subtype 2: PR ≥ 20%/Ki67≥20%; Subtype 3: PR < 20%/Ki67≥20%; Subtype 4: PR < 20%/Ki67<20%). Cox regression analysis was used to correlate tumor characteristics with DFS and BCSS.
Results
The rates of progression disease were 8%, 19%, 30% and 12% in subtype 1, 2, 3 and 4, respectively. Low PR expression (<20%) resulted an independent poor prognostic factor for DFS in patients with high Ki67 value (≥20%). The median DFS was 12.6 months and 10.1 months in subtype 2 and subtype 3, respectively (p = 0.025) (Fig.1). The rates of cancer death were 5%, 12%, 24% and 12 % in subtype 1, 2, 3 and 4, respectively. Consistent with DFS results, a statistically significant correlation of PR expression level and BCSS was reported in patients with high Ki67 index (the median BCSS was 12.9 months in subtype 2 versus 10.5 months in subtype 3, respectively) (p = 0.04). No correlations between survival and PR expression were demonstrated in patients with low Ki67 value (<20%), probably due to the small sample size in the subtypes 1 and 4 groups.
Conclusions
Our study revealed different outcomes among patients with early BC according to different PR expression levels. Noteworthy, in patients with Ki67 ≥20%, low PR expression levels (<20%) could be considered as a prognostic marker suggesting to re-evaluate PR status as a potential therapeutic guide in ER+/Her2- early BC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
A. Diana: Travel / Accommodation / Expenses: Ipsen, Novartis, Pharmamar, Italfarmaco. F. Carlino: Travel / Accommodation / Expenses: Italfarmaco, Gentili. E. Franzese: Travel / Accommodation / Expenses: Roche. S. Centonze: Travel / Accommodation / Expenses: Thesaro, Roche, Gentili. F. De Vita: Advisory / Consultancy: Roche, Amgen, Celgene, Lilly. F. Ciardiello: Advisory / Consultancy: Merck, Roche, Lilly, Bayer, Amgen, Pfizer, Servier. M. Orditura: Honoraria (self): Epionpharma, Italfarmaco; Travel / Accommodation / Expenses: Roche; Research grant / Funding (institution): EISAI. All other authors have declared no conflicts of interest.
Resources from the same session
3425 - Feasibility and impact of prospective DPYD screening in the Irish population
Presenter: Mohammed Zameer
Session: Poster Display session 2
Resources:
Abstract
1972 - Diet-derived metabolites and the risk of colorectal cancer: a nested case-control study in a population-based cohort, the Singapore Chinese Health Study
Presenter: Dawn Chong
Session: Poster Display session 2
Resources:
Abstract
4103 - Loss of subcutaneous adipose tissue during chemotherapy predicts reduced survival in patients with incurable colorectal cancer undergoing palliative therapy
Presenter: Erin Stella Sullivan
Session: Poster Display session 2
Resources:
Abstract
4309 - Obese and overweight is associated with better prognosis in metastatic colorectal cancer patients treated with bevacizumab.
Presenter: Bozena Cybulska-Stopa
Session: Poster Display session 2
Resources:
Abstract
3554 - Patient characteristics associated with poor performance status, ECOG 2-3, and effect on survival in 1086 Finnish metastatic colorectal cancers (mCRC) nationwide (prospective RAXO study)
Presenter: Pia Österlund
Session: Poster Display session 2
Resources:
Abstract
4572 - Discovery and Diagnosis of Metastatic Colorectal Cancer (mCRC) in the Real World: Final Results from a European Survey
Presenter: Iga Rawicka
Session: Poster Display session 2
Resources:
Abstract
4783 - Adherence to recommended intake of calcium and colorectal cancer risk in the HEXA study
Presenter: Jeeyoo Lee
Session: Poster Display session 2
Resources:
Abstract
5106 - Body size, sex and sidedness of incident colorectal cancer in a prospective Swedish cohort study
Presenter: Christina Siesing
Session: Poster Display session 2
Resources:
Abstract
3364 - Middle East & North Africa Registry to characterize RAS mutation status and tumor specifications in recently diagnosed patients with metastatic colorectal cancer (MORE-RAS Study)
Presenter: Mohamed Oukkal
Session: Poster Display session 2
Resources:
Abstract
3668 - Patient Demographics and Management Landscape of Metastatic Colorectal Cancer in the Third Line Setting: real-world data in an Australian Population
Presenter: Sandy Tun Min
Session: Poster Display session 2
Resources:
Abstract