Breast Cancer Diagnosis

Diagnosis of breast cancer is made through a process called triple assessment, which includes

  • clinical examination,
  • imaging procedures (e.g., mammogram, breast ultrasound, magnetic resonance imaging [MRI scan]), and
  • biopsy (surgical removal of tissue for microscopic examination) of a mass detected by physical examination or mammogram (x-ray of the breast).

Breast Cancer Screening

The American Cancer Society released new breast cancer screening guidelines in October 2015. The following recommendations are for women who are at average risk for breast cancer and do not have breast cancer symptoms:

  • The American Cancer Society no longer recommends breast self-exams (BSE) or breast exams performed by a health care provider.
  • At the age of 40, women should begin discussing breast cancer screening options with their health care provider.
  • Women should have annual mammograms beginning at the age of 45 until the age of 55.
  • At 55 years of age, women may begin having mammograms every other year.
  • Regular mammograms should continue for as long as the woman is in good health. Older women with serious health problems should evaluate the benefit of breast cancer screening with their physician.

Women with a family or personal history of breast cancer should discuss early detection testing with their physician, including mammogram, breast ultrasound and MRI with computer-aided detection (CAD).

According to the U.S. Centers for Disease Control and Prevention (CDC), about 1 in 4 women reported not being up-to-date with breast cancer screening recommendations in the National Health Interview Survey (2013). Screening data showed that 72.6 percent of women between the ages of 50 and 74 had a mammogram—a percentage that showed little change from previous years.

If women choose to perform breast self-examination, the exam should be performed about 1 week after the menstrual period ends every month. Health care practitioners can instruct patients in the correct method of performing this examination.

If clinicians perform breast examinations, the health care provider examines the breasts (including the nipples and areola) for retractions, skin changes, and discharge. Then, the breasts and underarms are palpated (felt with the fingers). Health care practitioners often teach patients how to perform breast self-examination while doing a clinical examination.

During a mammogram, the breast is compressed between two plates for a few seconds and x-rays are taken. The procedure uses low amounts of radiation. Compression causes some discomfort.

Ultrasound may be used to determine if a mass detected by examination or mammogram is a cyst or a solid lesion. Ultrasound uses high-frequency sound waves to create an image of the breast on a computer screen. Needle aspiration may be performed if ultrasound reveals a suspicious lesion.

If a diagnosis of breast cancer is made, the cancer is staged to determine the course of treatment.

A Note About Clinical Trials

Clinical trials are studies that are done on promising screenings, treatments or other medical interventions to confirm effectiveness and safety. There are some clinical trials that are specific to breast cancer screening. Deciding to enter into a clinical trial is a personal choice, and it's wise to discuss the idea with your physician.

If you're interested in learning about what breast cancer screening trials are available, talk to your health care provider, or visit or—the official site of the National Cancer Institute (NCI). You may also want to check out; though this is not a government site, it summarizes NCI information in an easy-to-read way and links you to the full posts for more information.

Updated by Remedy Health Media

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 14 Aug 1999

Last Modified: 23 Oct 2015