Which type of breast cancer is the most common?

Hormone receptor (HR)-positive breast cancer is the most common type of breast cancer diagnosed. This form of cancer is characterized by the presence of hormone receptors, specifically estrogen and/or progesterone receptors, on the cancer cells. These receptors can promote the growth of tumors in response to hormones circulating in the body, which can influence treatment options and prognosis.

The prevalence of HR-positive breast cancer is significant, making it the most frequently diagnosed subtype. Treatment approaches often involve hormone therapies, which can be quite effective for patients with HR-positive tumors. This understanding helps in tailoring individual treatment plans and improving patient outcomes.

In contrast, while triple-negative breast cancer, HER2-positive breast cancer, and inflammatory breast cancer are also important subtypes, they are less common compared to HR-positive breast cancer. Triple-negative breast cancer lacks these hormone receptors and tends to present more aggressive features. HER2-positive breast cancer is defined by overexpression of the HER2 protein and represents a specific target for therapies but is also less frequently diagnosed than HR-positive cases. Inflammatory breast cancer, although aggressive and with distinct symptoms, is quite rare when compared to the other subtypes.