Medullary carcinoma

Medullary carcinoma is a histologically characteristic form of invasive ductal breast carcinoma. It constitutes about 4-5% of all invasive breast cancers. Compared to other breast carcinomas, they tend to metastasize to lymph nodes much less readily.

Macroscopic features include:

• relatively larger than ductal NOS (up to 10cm)
• consistency soft and fleshy
• well-circumscribed
• smooth surface

Histologically, they are characterised by:

• little stroma
• cells growing in irregular sheets
• lymphocytic infiltrate - response may contribute to its relatively better prognosis
• occasionally glandular patterns - medullary adenocarcinoma

Reference

1. Watkins EJ. Overview of breast cancer. JAAPA. 2019 Oct;32(10):13-17.