Clinicopathologic Characteristics of Oestrogen Receptor-Positive/Progesterone Receptor-Negative/Her2-Negative Breast Cancer According to a Novel Definition of Negative Progesterone Receptor Status: A Large Population-Based Study from China.
OBJECTIVE
A lack of progesterone receptor (PgR) expression in oestrogen receptor-positive (ER+) tumours is associated with worse survival. PgR status is usually defined as positive or negative using 1% positive nuclei as a cut-off point. In this study, we aimed to assess the clinicopathologic characteristics of ER+/PgR-/HER2- tumours by comparing them with ER+/PgR+/HER2- tumours using a PgR cut-off point of 20% as a divisive criterion.


METHODS
We analysed 1,522 patients with primary breast cancer who had undergone surgery at the Cancer Center of Fudan University between 2012 and 2014. Age, grade, tumour size, lymph node status and lymphovascular invasion were assessed. Multinomial logistic regression, linear regression and chi-square test models were applied to assess associations between ER, PR and clinical features.


RESULTS
ER+/PgR-/HER2- tumours showed poorer clinicopathologic characteristics relative to ER+/PgR+/HER2- tumours using a PgR threshold of 20% instead of 1%. The clinicopathologic characteristics did not differ between tumours with purely negative PgR expression and tumours with a PgR percentage ranging from 1% to 19%. The prognostic significance of PR expression appeared more pronounced in patients under a high Ki-67 status than those under a low Ki-67 status.


CONCLUSIONS
Based on these findings, we propose the use of a novel threshold of 20% to define PgR status. Nevertheless, the impact of this new criterion on patient management and clinical treatment requires additional study.
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
An-qi
AQ
Li
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
Shu-ling
SL
Zhou
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
Ming
M
Li
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
Yan
Y
Xu
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
Ruo-hong
RH
Shui
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
Bao-hua
BH
Yu
Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, P.R. China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, P.R. China.
Wen-tao
WT
Yang
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000453:epidemiology / Q000378:metabolism* / Q000473:pathology*; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D011159:Population Surveillance; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D047368:Tumor Burden; D055815:Young Adult
D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone