Overview of Mammography
Breast cancer is the second most common type of cancer in women, only behind skin cancer, accounting for 14% of all new cancer cases in the United States. It’s typically found in women between the ages of 55 and 64, and the risk keeps increasing as one gets older. Finding breast cancer early makes it more likely that treatment will be successful and less harmful.
While advancements in breast cancer treatments have helped reduce the number of people dying from the disease, getting a mammogram— a type of breast screening— is the most effective way to catch the disease early and reduce the risk of dying from it. Because of this, The American College of Radiology suggests that women with an average risk of breast cancer start getting mammograms at age 40.
There are several ways to discover potential cases of breast cancer— a mammogram, a breast ultrasound, and an MRI are a few common ones. However, to confirm if it’s actually breast cancer, doctors have to examine a small piece of the suspicious tissue (a procedure called a biopsy).
Screening for breast cancer is primarily done with a mammogram. If the mammogram shows something unusual or unclear, further tests may be needed such as a more detailed mammogram, an ultrasound, an MRI, a biopsy, or a combination of these tests. The article discussed the process and things to consider when getting a mammogram for breast cancer screening.
Anatomy and Physiology of Mammography
The breast is made up of fat and glandular tissue, containing a mix of exocrine glands, ducts, tissues, blood vessels, and nerves. This substances extends from the second to sixth ribs and is bordered by the breastbone and the middle of the armpit. For easy identification of different parts, the breast is usually divided into smaller parts using the nipple as a reference point. For instance, the breast can be divided into four quadrants – top/bottom and left/right.
It’s worth mentioning that the upper outer parts of the breasts often have breast tissue that continues into the armpit. This spot is important for breast x-rays (mammograms) because it’s challenging to get clear images without proper positioning of the patient. Plus, one of the main networks of lymph vessels (which help your body get rid of toxins) passes through the armpit. Therefore, this area may reveal abnormal lymph nodes during the imaging process.
Mammograms work by showing how different breast tissues absorb x-rays. For example, fat absorbs fewer x-rays than glandular tissue and connective tissue, and it shows up as a gray color during the mammogram. Dense mineral deposits, like calcium in the skin or tumors, can be easily identified because they appear bright white. However, it can be hard to see small lumps if other tissues are overlapping. To solve this, two standard views are taken: the view from top to bottom (craniocaudal view) and the diagonally sideways view (mediolateral oblique). This allows the radiologist to see any overlaps and help clarify any uncertain areas. Getting a complete picture may require additional views from different angles.
Newer screening methods like 3D imaging, let radiologists move through breast tissue in layers, thereby lessening the overlapping effect. A usual mammogram can show the skin surface, the nipple, the main breast ducts, glandular tissue, veins, fat, muscles, and sometimes lymph nodes.
It’s important to note that the amount of glandular tissue and fat in a person’s breast can vary greatly. For instance, hormonal changes during pregnancy and breastfeeding can increase the glandular tissue, and when a woman stops breastfeeding, this tissue can decrease. Dense breast tissue shows up as a white color on a mammogram and can make it harder to detect breast cancer. Moreover, people with dense breast tissue are more at risk of developing breast cancer. Hence, it is crucial to take special care when imaging dense breasts, and alternative screening methods like ultrasound or MRI should be considered if the mammogram is unclear.
Every mammogram needs to be assessed to make sure the quality is good enough, and that the positioning is correct. If these factors are not right, it’s possible that breast cancers could be missed. Considering this, the positioning of the breast over the pectoralis major muscles (large muscles under the breast) is checked. On the mammogram, these muscles should show up as a striped appearance that is denser than the fat and glandular tissue above it. As a rule, the breast positioning is considered correct only if a line is drawn from the nipple directly back to the muscle in the mammogram images. In addition, the view from top to bottom is not considered good if this line is more than 1 cm from the muscle.
Why do People Need Mammography
Many respected medical groups give advice on how to check for breast cancer. These groups include the American College of Obstetrics and Gynecology, the American College of Radiology, the Society for Breast Imaging, the American Cancer Society, the American Medical Association, the National Comprehensive Cancer Network, and the United States Preventative Service Task Force. Each of these organizations has a slightly different suggestion on the best way to detect breast cancer, but we won’t go into those differences here.
According to the American College of Radiology, all women who are 40 years old and above, and have an average chance of getting breast cancer, should have a mammogram every year. A mammogram is a special kind of x-ray of the breasts. Women should continue to get these yearly mammograms as long as they are in good enough health to receive further tests or treatments if needed, and they are willing to do so. There’s no specific age to stop getting mammograms. Instead, it depends on your overall health condition. Although, breast cancer is commonly found in women aged 50 to 60, the risk increases as women get older. Having regular mammograms can help find breast cancer early before it has a chance to grow or spread. A mammogram can also find changes in the breast that could turn into cancer but aren’t yet. Women are considered to have an average risk if they have less than a 15% chance of getting breast cancer in their lifetime.
Some women have a higher chance of getting breast cancer. These women may need to start getting mammograms earlier or have other tests in addition to mammograms. Women are seen to be at medium risk, or having a 15-20% lifetime risk of developing breast cancer, if they have any of the following: a prior personal history of breast cancer, unusual ductal hyperplasia (an abnormal growth of cells in the milk ducts) found on a previous breast biopsy or lobular neoplasia (an abnormal growth of cells in the milk production glands) found on a previous breast biopsy. If you fall into this intermediate risk category, you should still get a mammogram every year, but it may be beneficial to also get a breast ultrasound and maybe even a breast MRI. A breast ultrasound uses sound waves to create a picture of the inside of your breast and is especially useful if you have dense breast tissue, because the picture quality isn’t affected by the increase in breast density.
Women with a 20% or higher lifetime risk of developing breast cancer are classified as high-risk. These women may need to start screening for breast cancer at an earlier age and possibly require additional screening tests. You might be considered high-risk if you carry specific gene mutations, such as BRCA 1 and 2, have a strong family history of breast cancer, or have received radiation therapy to the chest when you were between the ages of 10 to 30. If you have a family history of breast cancer, you should start getting mammograms ten years earlier than the age at which your youngest first-degree relative was diagnosed with the disease. However, you shouldn’t start this earlier screening before the age of 30, because there is a concern that women under 30 might be more sensitive to the radiation used in mammograms. In addition to mammograms, it’s recommended that women at high risk also get a breast MRI, as this test is better at finding breast cancer.
Doctors recommend that women should have their risk of breast cancer assessed by the time they turn 30. This will help them decide when they should start getting breast cancer screening tests. Mammograms are not recommended for men who have breast tissue, known as gynecomastia.
When a Person Should Avoid Mammography
There are no outright reasons to prevent a mammogram, which is a breast x-ray screening, but there are situations that need extra care. If a woman has signs or symptoms of breast cancer, like feeling a growing lump in her breast, she should have specific diagnostic mammogram and ultrasound tests rather than just standard screening. Diagnostic tests involve extra techniques to get a more detailed look at the breast tissue. The distinction between screening and diagnostic mammograms comes down to the level of detail and additional imaging methods used.
For healthy women who are not showing signs and have an average chance of getting breast cancer, it’s typically not advised to get a mammogram before they turn 40. This is because younger women often have denser breast tissue and mammograms are less effective at finding cancer in these cases. There’s also a chance of false-positive results, which could lead to additional imaging or even a biopsy that might not have been necessary. However, when a woman turns 30, it’s recommended she gets evaluated to see if early screening is suitable.
Mammograms use a type of x-ray radiation. Even though the radiation used in mammograms is weaker than the radiation in other medical scans like CT scans or regular x-rays, there’s still some theoretical risk with exposure. So, for pregnant or breastfeeding women, special care has to be taken. The radiation dose to a baby during pregnancy is very small and doesn’t cause negative effects on the baby’s development. However, mammograms should be customized for each pregnant patient’s needs. Whenever it’s possible, techniques that reduce radiation should be used. Pregnant women showing no signs of breast cancer and having an average risk don’t need to get a mammogram until after they give birth, but it’s crucial to examine any signs of breast cancer during pregnancy immediately.
Breastfeeding moms also need special consideration because their milk-producing lobules can block x-rays, making it harder to detect potentially harmful or cancerous lumps. However, breastfeeding or pumping before the mammogram can decrease the density of the breast tissue and increase the effectiveness of the mammogram. So, breastfeeding doesn’t make mammograms unviable, but these women need to know these details before they undergo any imaging tests.
Equipment used for Mammography
Mammography is a medical test that uses x-rays to examine the different parts of the breast. In the past, mammograms were done with traditional film-based devices. Nowadays, film mammography has been largely replaced by more advanced technologies that use ‘phosphor storage’ or ‘direct digital capture’. Phosphor storage uses a special crystal that changes x-rays into visible light, which is then converted into a digital image. On the other hand, direct digital capture uses a type of sensor that can directly convert the x-ray into a digital picture.
These newer technologies are better than the old film mammography because the contrast and level of detail in the image can be adjusted after it’s taken. This means doctors can spot and understand small differences within the breast tissues better for accurate diagnosis.
Lately, a method called digital breast tomosynthesis (DBT), also referred to as “3D mammography”, is being preferred. In DBT, several mammographic images are captured in a sequence from different angles along a curve. Using computer programs, these images are then combined to form a series of highly detailed, thin slice images. The benefit of this method is that it overcomes the problem of overlapping tissues that’s common in traditional mammography, allowing doctors to examine the breast in three dimensions. Research shows that DBT can more accurately detect cancer and reduce false alarms. It can also spot less aggressive forms of cancer, which could mean better treatment options and outcomes for patients. Therefore, DBT is quickly becoming the standard method for mammograms.
The basic equipment for a mammogram includes an x-ray generator, an image detector, and a breast compression paddle. The x-ray generator and the image detector are fixed at a set distance from each other and are positioned at right angles. The entire unit can be turned to get the necessary mammogram views. Mammography technicians also need additional safety gear. This includes a shield for protection against x-rays and a remote control to operate the devices.
Who is needed to perform Mammography?
Getting a mammogram, which is a type of breast scan, involves a few important people. The first is a radiology technologist – this is the person who sets up the imaging equipment, helps you get into the right position, and captures the images of your breast. Next, there are medical physicists, who make sure that the machine works accurately and gives good quality pictures.
Now that most mammograms are digital, we also need an IT team on board. They make sure that the digital images get sent correctly, stored safely, and can be viewed easily. Finally, the diagnostic radiologist (a doctor who specializes in reading medical images), will look at the pictures of your breast to see if there are any changes or signs of disease. They also double-check to make sure that the mammogram was done correctly.
All of these team members have been trained to meet certain standards, as set by the Mammography Quality Standards Act. This makes sure that they all know what they’re doing and can help you get the best possible care during your mammogram.
Preparing for Mammography
Before a mammogram exam, the equipment used needs to be carefully checked and adjusted to make sure it’s working correctly. A trained x-ray technician can perform these checks, and if there are any issues, a medical physicist can help resolve them.
When a patient arrives for a mammogram, several things should happen. First, the medical team should confirm the patient’s identity and explain what a mammogram entails. They should also review the patient’s personal and family health history, especially any history of breast cancer or changes to the breasts such as lumps, skin changes, or tenderness. Any past surgeries, such as breast enlargement or reduction, or procedures to take tissue samples or remove lymph nodes, would also be important to note.
For the exam, the patient will need to remove upper body clothing and wear a hospital gown instead. If the patient has any moles or scars on the breasts or nearby areas, these should be marked with a special material that shows up on the x-ray. This helps to distinguish these normal skin features from any potential problems and reduces the need for extra callbacks.
Lastly, the technician will enter the patient’s details into the mammogram equipment to prepare for the start of the exam.
How is Mammography performed
When you have a screening mammogram, the doctor usually takes two standard pictures of each breast. These pictures have technical names due to the direction in which the x-ray beam travels: craniocaudal (CC) and mediolateral oblique (MLO).
For the CC image, your breast is placed on the image detector, and a paddle compresses it from top to bottom. This is done to get as much of your breast tissue as possible in the picture, even including parts like the area underneath your breast and possibly some of the muscle underneath (pectoralis major). This is important so that no areas that might have unhealthy tissues are missed. The pressure on your breast is adjusted considering your breast size and your comfort level. Proper pressure is necessary as without it, the inside tissues of your breast might not separate well; the x-rays may not spread evenly across your breast, more radiation might get used, and the resultant picture might be blurry. It is important to ensure that no part of your breast is left out of the picture.
For the MLO image, the machine is typically angled at 40 to 60 degrees. In this case, the image is preferred over a regular side view because it includes the area in the armpit and the tail of the breast tissue going into this area. Similar to the CC view, the aim is to show as much breast tissue as possible. For consistency, a line drawn from the nipple to the chest wall in the MLO view should be within 1cm of the same line drawn in the CC view. It is crucial to get as much of the breast tissue in the armpit area into the image, as cancers may from in this region.
If necessary, your doctor may decide to have more detailed images taken in addition to the standard mammogram. These can be either by using a smaller paddle to apply pressure in certain areas or by magnifying the area in question. The paddle is placed by predicting the location of the area of interest based on the regular mammogram images. Magnifying images is done by lifting the breast away from the image detector to enlarge the tissues. After the pictures are taken, findings are described by their location using a clock-face system and their distance from the nipple. Overall, these views are essential to ensure your medical team can thoroughly examine your breast tissue.
Possible Complications of Mammography
Having a mammogram, a type of breast examination, is generally safe and doesn’t cause major problems. However, slight complications can occur because of the pressure applied to the breasts during the test. This pressure could lead to bruising, tiny collections of blood under the skin (small hematomas), and temporary discomfort. There could also be problems with the quality of the images taken during the mammogram if the breast isn’t positioned correctly. But with careful handling and the right technique, this complication can be avoided.
What Else Should I Know About Mammography?
Mammograms (a type of breast X-ray) are currently the primary way to check for breast cancer. They have been found to help lower the death rate from breast cancer and lessen the harm caused by treatment. However, mamograms aren’t perfect. They can miss almost 25% of cancers that are found clinically within a year after the screening.
To get a good quality mammogram, you need both the right equipment and proper technique. In fact, the standards for this test are higher than for almost any other type of x-ray.
Knowing when to get a mammogram, how it’s done, and what problems might occur is crucial for providing top-notch care to patients who may be at risk of developing breast cancer.
