Table of Contents
Definition / general | Terminology | Clinical features | Microscopic (histologic) images | Positive stains | Additional referencesCite this page: Luminal phenotype. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/breastmalignantluminal.html. Accessed July 14th, 2017.
Definition / general
- Defining molecular feature is ER expression
- Major difference between luminal A and luminal B breast cancers is degree of proliferation and HER2 expression signature, which is more pronounced in luminal B (Breast Care (Basel) 2011;6:258)
Terminology
- Not part of current WHO breast classification
Clinical features
- Classification is based on gene expression (molecular) profile studies; subtype reflects clustering of genes activated by ER signaling pathways
- Distribution by molecular typing is: luminal A: 71%; luminal B: 8%; HER2+: 6% basal-like: 15% (Ann Surg Oncol 2009;16:2705)
- Luminal subtypes include luminal A (ER+ [strong], PR+, HER2-) and luminal B (ER+ [weak / moderate], PR-, sometimes HER2+)
- Some authors also include categories of luminal A-HER2 and luminal B-HER2 hybrids (Int J Clin Exp Pathol 2009;2:444)
- Luminal cytokeratins are CK7 / 8, 18 and 19
- Luminal A and B subtypes are associated with mutations in E-cadherin and MAP2K4, and amplifications of Cyclin D1, HER2 and HDM2 (Breast Cancer Res Treat 2010;121:53)
- Luminal A breast cancers are usually low grade, with slow growth and better prognosis than luminal B (J Natl Cancer Inst 2009;101:736)
- Luminal B breast cancers: some are HER2+, but the major biological distinction from Luminal A is the proliferation signature, in which CCNB1, MKI67 and MYBL2 genes have higher expression in luminal B than in luminal A tumors (BMC Genomics 2006 Apr 27;7:96)
- Luminal A and most grade 1 luminal B (HER2+) cases are low proliferative (Breast Cancer 2014;21:47)
Microscopic (histologic) images
Additional references





