[Medical Q&A] Why are many breast cancers discovered in the late stages?

Planner: Chinese Medical Association

Reviewer: Rong Long, Chief Physician, Peking University First Hospital

Breast cancer is divided into stages I, II, III, and IV. Stages I and II are early stages, with smaller tumors and fewer lymph node metastases; stage III is still confined to the breast, but the tumor is larger and there are more lymph node metastases; in stage IV, distant metastases will occur, which is what we call "late stage". Simply put, distant metastases of breast cancer in any location are considered late stage.

Some women do not pay much attention to their breast health and wait until they have symptoms and feel a large lump in the breast before going to the hospital for examination. By then, distant metastasis may have occurred. Some breast cancers are more malignant and develop faster, and are prone to distant metastasis and become advanced.

Therefore, it is recommended that women undergo regular screening for two cancers (cervical cancer and breast cancer) for early detection and early treatment. Currently, the main means of breast cancer screening are B-ultrasound and mammography. For women over 40 years old, it is recommended to have B-ultrasound and mammography once a year; for some high-risk women, it is recommended to have an annual examination at the age of 25 to 30.

The time it takes for breast cancer to develop from early to late stages is uncertain. Some breast cancers do not metastasize, so they will not progress to the late stage; some breast cancers (such as triple-negative breast cancer) are more malignant and may peak in metastasis in 2 to 3 years; some hormone receptor-positive breast cancers are relatively less malignant and may metastasize in about 10 years. Many patients with early breast cancer can be cured through timely treatment and will not develop to the late stage; even for advanced breast cancer, there are many treatments and methods, such as chemotherapy, targeted therapy, immunotherapy, endocrine therapy, etc. Many patients with advanced breast cancer can achieve long-term survival through active treatment.