Molecular intrinsic breast tumor subtypes were immunohistochemically determined in a large unselected older breast cancer cohort.
Primary endpoint was Relapse Free Period, taking into account the competing risk of mortality, and relative survival.
Patients with a Luminal A subtype had the lowest, patients with a Basal-like or ERBB2 subtype the highest risk of recurrence.
The worst relative survival was observed for the ERBB2 subtype.
This study supports the use of molecular subtyping in the older breast cancer patients for prognostication.