Inflammatory responses can be triggered by cytokines (e.g., tumour necrosis factor alpha (TNF‐α), interleukin 1 beta (IL‐1β) and cyclooxygenase‐2 (COX‐2)) and adhesion molecules (e.g., intercellular adhesion molecule 1 (ICAM‐1)) after CCH. Here, TNF is linked to columnar cell hyperplasia of the breast.