High quality mammography can detect very early breast cancer before it has spread.
One objection to screening mammography has been that it has resulted in "unnecessary" surgery for benign problems which
looked worrisome on a mammogram. First of all, that occurs less often than biopsies that result from a physical exam. Secondly,
advanced ultrasound exams and image-guided needle biopsies can now drastically lower the need for surgical biopsy.
SCREENING MAMMOGRAMS
WHO ARE WE TALKING ABOUT? A screening mammogram is a study done on a woman who does not have a physical sign of
breast cancer. This is different than a study for a woman who has discovered a lump or whose physician has found a "mass".
The majority of breast cancer occurs in women with no special "risk factors." Therefore, every woman over a certain age
should be periodically "screened" for breast cancer.
A "CERTAIN AGE"
There has been some controversy about the appropriate age at which to begin regular screening mammography. Some "authorities"
have claimed that there was little evidence for the value of screening before the age of fifty.
However, by 1993 five of eight major trials had shown a mortality reduction from breast cancer in screened woman between 40
and 50 years of age. A review of major trials recently (March 1996) showed a 24 percent decrease in deaths from breast cancer
among woman age 40 to 50 who underwent screening. This result was from screening every two years. Estimates of up to 35 percent
decrease in the breast cancer death rate are made for yearly screening.
Since current techniques are associated with no measurable risk, regular (yearly) screening mammography should begin at the
age of 40. Screening before that age is not likely to be worthwhile unless there is a very strong family history of breast
cancer occurring at a young age. In high risk patients a strong family history (mother, sister, or daughter) at an earlier age,
the patient should begin screening 10 years before the earliest age onset of this first-degree relative, but not before the age
of 25. For example, a patient with a sister having breast cancer detected at age 36 should begin screening as early as 26 years
of age.
Patients with very dense breasts on mammography may also be candidates for periodic ultrasound, in selected cases MRI of the
breasts, due to the known reduced sensitivity of screening mammography in these patients.