A 55-year-old woman presents with a breast mass. Core biopsy shows invasive carcinoma that is ER+, PR+, HER2−. Which molecular subtype does this correspond to?

• A HER2-enriched subtype
• B Triple-negative (basal-like) subtype
• C Luminal B subtype
• D Luminal A subtype ✓

Explanation

Luminal A breast cancer is ER+, PR+, HER2−, and has low Ki-67 proliferation index. It has the best prognosis among breast cancer subtypes and is treated with endocrine therapy alone in most cases. Luminal B is also ER+ but HER2+ or has high Ki-67. HER2-enriched is ER−, PR−, HER2+. Triple-negative (basal-like) is ER−, PR−, HER2−.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.