What is the most common type of breast cancer?

Invasive ductal carcinoma is recognized as the most common type of breast cancer, accounting for approximately 70-80% of all breast cancer cases. This type of cancer originates in the milk ducts and has the capacity to invade surrounding breast tissue, which is a key characteristic that defines it as "invasive."

The prevalence of invasive ductal carcinoma is significant in clinical practice, as it tends to present with a distinct lump in the breast and may also manifest with changes in breast shape or skin texture. Early detection and treatment are critical, and understanding its commonality can help healthcare professionals prioritize screening and diagnostics for patients.

In contrast, other types, such as invasive lobular carcinoma, are less prevalent and have different histological features and behaviors. Non-invasive carcinoma, such as ductal carcinoma in situ (DCIS), represents a stage where cells are confined to the ducts and not invading surrounding tissue, while triple-negative breast cancer is a subtype defined by the absence of hormone receptors and HER2 expression, making it distinct in terms of treatment and prognosis rather than prevalence. Thus, the recognition of invasive ductal carcinoma as the most common type underscores the importance of this knowledge in clinical diagnosis and patient management.