Clinical outcome and global gene expression data support the existence of the XXXX receptor-negative/ @entity1420 receptor-positive invasive @entity0 phenotype.

@entity172 @entity1 @entity0 @entity1420 @entity5
UNASSIGNED: The presence or absence of @entity172 and @entity1420 steroid hormone receptor expression (ER, PR) is an essential feature of invasive @entity0 and determines prognosis and endocrine treatment decisions. Among the four ER/PR receptor phenotypes, the ER-/PR+ is infrequent, and its clinical relevance has been controversially discussed. Thus, we investigated its clinical significance and gene expression pattern in large datasets. In a retrospective clinical study of 15,747 @entity0 @entity1 , we determined the ER/PR subtype survival probabilities using Kaplan-Meier and Cox regression analyses. From The @entity5 (TCGA) @entity0 dataset, PAM50 expression signature and pathway analyses were performed to test for distinct molecular features. In our cohort, the ER-/PR+ phenotype has been observed at a frequency of 4.1  % and was associated with an improved 10-year survival for stage I @entity5 compared to the ER+/PR+ reference subtype (median; 95  % CI 88.1  %; 83-93 vs. 84.3  %; 82-86  %, P  =  0.024) as was confirmed by multivariate analysis over the entire follow-up (HR 0.59, 95  % CI 0.38-0.92, P  =  0.021). This association lacked significance when including all stages. ER-/PR+ @entity1 treated with antihormonal agents (34.5  %) had shorter survival compared to their non-treated counterparts (Log-rank P  =  0.0001). PAM50 signatures suggest a distinct configuration for the ER-/PR+ phenotype. This specific phenotype has been further separated by a set of 59 uniquely expressed genes. Our study supports the notion of the existence of an ER-/PR+ phenotype with clinical and molecular features distinct from the large group of ER+/PR+ @entity1 .
