MAMOGRAFIA
Mamografia este cea mai buna modalitate de depistare a cancerului de sān īn stadiile cele mai tratabile - īn medie cu cca. 1,7 ani īnainte ca femeia sa simta vreun nodul. De asemenea, mamografia localizeaza cancerele care sunt prea mici pentru a fi evidentiate īn cursul examenului clinic al sānului.
Mamografia este examinarea radiologica a sānului. Mamografia diagnostica se foloseste la diagnosticarea bolilor glandei mamare la femeile care au simptome. Mamografia de screening se foloseste pentru a depista boli ale 22522f516w sānului la femeile asimptomatice, adica la cele care nu par sa aiba probleme.
Desi radiografia ca metoda diagnostica se efectueaza de peste 70 de ani, mamografia moderna exista doar din 1969. Acesta a fost primul an īn care īn occident au aparut unitati de radiologie dedicate exclusiv examenului sānului. Īn unitatile moderne de mamografie echipamentul este conceput īn asa fel īncāt sa se foloseasca doze foarte scazute de radiatii, de obicei 0,1 - 0,2 razi per mamografie. Reglementarile īn vigoare sunt foarte stricte, īn sensul ca aceste unitati nu sunt avizate decāt īn conditiile īn care echipamentul este sigur si dozele de radiatii folosite sunt minime.
Many people are concerned about the exposure to x-rays, and rightly so, but the level of radiation in up-to-date mammograms does not significantly increase the risk for breast cancer. To put dose into perspective, a woman who receives radiation as a treatment for breast cancer will receive several thousand rads. If a woman had yearly mammograms beginning at age 40 and continuing until 90, she will have received 10 rads.
In order to perform a mammogram, the breast is compressed to flatten and spread the tissue. Although this may be temporarily uncomfortable, it is necessary in order to produce a good mammogram. The compression only lasts a few seconds, and the entire procedure for screening mammography takes about 20 minutes. This procedure produces a black and white image of the breast tissue on a large sheet of film that is "read," or interpreted, by a radiologist. The physician reading the films will look for several types of changes. Screening mammography usually involves two views (x-ray pictures) of each breast. For some patients, such as women with breast implants, additional pictures may be needed to include as much breast tissue as possible. Women who are breast-feeding can still get mammograms. They can express their breast milk before the mammogram.
The x-ray machine for mammography
Calcifications are tiny mineral deposits within the breast tissue which appears as small white spots on the films. Calcifications are divided into two categories, macrocalcifications and microcalcifications. Macrocalcifications are coarse (larger) calcium deposits that most likely represent degenerative changes in the breasts, such as aging of the breast arteries, old injuries, or inflammations. These deposits are associated with benign (noncancerous) conditions and do not require a biopsy. Macrocalcifications are found in about 50 % of women over the age of 50, and in about 10 % of women under the age of 50.
Microcalcifications are tiny (less than 1/50 of an inch) specks of calcium in the breast. An area of microcalcification that is seen on a mammogram does not always mean that cancer is present. They may appear singly or in clusters. The shape and arrangement of microcalcifications help the radiologist judge the likelihood of cancer being present. In some cases, the microcalcifications do not even indicate a need for a biopsy. Instead, a doctor may advise a follow-up mammogram within 3 to 6 months. In other cases, the microcalcifications are more suspicious and a biopsy is recommended.
Another important change that can be seen on a mammogram is a mass, which may occur with or without calcifications. Masses can be due to many things, including cysts and fibroadenomas, but may be cancer and usually should be biopsied if they are not fluid-filled cysts. A cyst, which is a benign collection of fluid in the breast, cannot be diagnosed by physical exam alone, nor can it be diagnosed by mammography alone. Either breast ultrasound, or removal of the fluid with a needle (aspiration), is used to confirm that a mass is a cyst. If a mass is not a cyst, then further imaging may be obtained. As with calcifications, a mass can be caused by benign breast conditions, or by breast cancer. Some masses can be monitored with periodic mammograms, while others may require immediate or delayed biopsy.
A mammogram, while suggestive, cannot prove that an abnormal area is cancer. To confirm whether cancer is present, a small amount of tissue must be removed and examined under a microscope. This procedure is called a biopsy.
For more information on imaging examinations for early detection and diagnosis of breast diseases, refer to the American Cancer Society document "Mammography and Other Breast Imaging Procedures."
Case history:
Kate Connelly discovered a lump while doing a breast self-exam. When examined by her doctor, he felt a pea-size lump under the nipple of her right breast and recommended she have a mammogram.
What is a mammogram?
A mammogram is a low-energy X-ray image of the breast. It can detect a cancerous or precancerous tumor in the breast even before the tumor is large enough to feel.
When is it ordered?
If any of the following signs are noticed, a mammogram is recommended: a breast lump, unusual breast pain, nipple discharge, a change in the shape of the breast, or a lump or skin thickening of the breast that does not disappear after your next menstrual period.
Women younger than age 40 with no family history of breast cancer or other symptoms should have a mammogram every 2 years, or as recommended by their doctor. Beginning at age 40, a mammogram is recommended every year because of age-related increased breast cancer risk. If you have a family history of breast cancer, ask your doctor when you should start having regular mammograms.
What does the mammogram find?
The radiologist looks for abnormalities in the breast tissue. On the mammogram, small calcium deposits, which may indicate a tumor, appear as white spots In addition, soft-tissue nodules or distortion of the normal fibrous and fatty breast tissue may be detected.
How do you prepare for a mammogram?
Schedule the mammogram for the week after your next menstrual period, when the breasts are less tender.
Do not use any talcum powder, lotion, or deodorant before the mammogram, because these products produce abnormal spots that may mimic calcium deposits.
What happens during a mammogram?
The procedure takes about half an hour. You will be asked to remove your clothing above the waist and to put on an examining gown. The technician positions your breast on an X-ray plate on the mammography machine. You may experience mild discomfort as another plate on the machine is lowered to compress the breast tissue. A beam of radiation is quickly passed through the breast, forming an image of the breast on X-ray film. Each breast is imaged in two different directions. Inform the technician if you have had a mammogram done previously; it is helpful to compare mammograms to detect subtle changes in the breast tissue.
RESULTS: Kate's mammogram shows a dense mass among the fatty tissue in her right breast. The doctor recommends a breast biopsy to determine whether the lump is benign or malignant. |
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