Breast Cancer Screening and Radiology- Wessam Bou-Assaly

Breast Cancer Screening and Radiology

 Wessam Bou-Assaly, MD

 

The goal of screening is to detect disease at its earliest and most treatable stage.

In breast cancer screening, a woman who has no signs or symptoms of breast cancer, undergoes a breast examination such as:

- Clinical breast exam: A physical examination of the breast by a doctor or other health professional

- Mammography: A low-dose x-ray exam that produces images of the breast called a mammogram.

Ultrasound and magnetic resonance imaging (MRI) can help supplement mammography by detecting breast cancers that may not be visible with mammography, or their characteristics are not well defined by mammogram and need better assessment. Neither MRI nor ultrasound is meant to replace mammography. Rather, they are used in conjunction with mammography in selected women.

Breast Cancer is cancer that forms in tissues of the breast, usually in the ducts and lobules (glands that make milk). It can occur in both men and women, although male breast cancer is rare. 

Breast cancer is the second leading cause of death from cancer in American women. About one woman in eight will be diagnosed with the disease over the course of her lifetime. 

Risks:

A woman’s risk of developing breast cancer increases with:

· age 

· a family history of the disease 

· a known BRCA1 or BRCA2 gene mutation

· beginning menstruation at an early age

· older age at birth of first child or never having given birth

· breast tissue that is dense 

· the use of hormones such as estrogen and progesterone

· obesity

· the consumption of alcoholic beverages

The Screening Recommendations:

· Screening mammography is recommended every year for women beginning at age 40 by the U.S. Department of Health and Human Services (HHS) and the American College of Radiology (ACR).

· The National Cancer Institute (NCI) advises women who have had breast cancer and those who are at increased risk due to a family history of breast cancer to seek expert medical advice about the frequency of screening and whether they should begin screening before age 40. According to American Cancer Society guidelines, most women at high risk should begin screening with MRI and mammography at age 30 and continue for as long they are in good health.

· Women should see their radiologist or primary care doctor to determine when to begin and how often to undergo breast cancer screening.

Breast cancer screening

-Clinical Breast Exam 

Physician carefully examines the breasts and underarm area for nodules, masses or lymph nodes. Women may also perform a breast self-exam by checking their own breasts for lumps or changes in size or shape. The clinical breast exam and breast self-exam can help women become more familiar with the regular look and feel of their breasts and more readily identify changes.

-Screening Mammography

Mammography is a type of x-ray examination used to examine the breasts. This type of imaging involves exposing the breasts to a small amount of radiation to obtain pictures of the inside of the breasts. 

During mammography, the breast is placed on a special platform and compressed with a paddle. The technologist will gradually compress the breast and while you hold still, an image will be taken producing a top-to-bottom view of the breast. You will be asked to change positions so the side view of the breast can be produced. 

-Breast Ultrasound

Breast ultrasound uses sound waves to create pictures of the inside of the breast. Breast ultrasound can capture images of areas of the breast that may be difficult to see with mammography. It can also help to determine whether a breast lump is a solid mass or a fluid-filled cyst.

-Breast MRI

During breast MRI, a powerful magnetic field, radio frequency pulses are used to produce detailed pictures of the inside of the breasts. MRI is helpful in finding abnormalities that are not visible with mammography or ultrasound. In general, MRI is used only in women at high risk for breast cancer.

Benefit of Mammography

· Imaging the breast improves a physician's ability to detect small tumors. When cancers are small, the woman has more treatment options.

· The use of screening mammography increases the detection of small abnormal tissue growths confined to the milk ducts in the breast, called ductal carcinoma in situ (DCIS). These early tumors cannot harm patients if they are removed at this stage, and mammography is the only proven method to reliably detect these tumors. It is also useful for detecting all types of breast cancer, including invasive ductal and invasive lobular cancer.

· Mammography has been shown to decrease the number of deaths from breast cancer when it is used for screening.

· No radiation remains in a patient's body after an x-ray examination.

      Risks

· There is always a slight chance of cancer from excessive lifetime exposure to radiation. However, the amount of radiation from a mammogram is very small and the benefit of an accurate diagnosis far outweighs the risk.

· False positive mammograms may occur. Five to 15 percent of screening mammograms require more testing such as additional mammograms or ultrasound. Most of these tests turn out to be normal. If there is an abnormal finding, a follow-up or biopsy may have to be performed. Most biopsies are done with a needle and confirm that no cancer was present. It is estimated that a woman who has yearly mammograms between ages 40 and 49 has about a 30 percent chance of having a false positive mammogram at some point in that decade and about a seven to eight percent chance of having a breast biopsy within the 10-year period.

Wessam Bou-Assaly: The Risks of X-Rays

 　

X-rays are produced when charged particles (electrons or ions) of sufficient energy hit a material and are suddenly decelerated upon their collision.

X-ray images are produced when a patient is placed in front of an X-ray detector and is then illuminated by short X-ray pulses. X-rays are absorbed by dense material with high atomic number such as bones, which are rich with calcium, and appear white on the resulting image. In the other hand, material with low or no atomic number, such as air in lungs, show up as dark patches on X-ray images because of their low absorption rates.

Type of X-Ray:

There are mainly 3 types of clinically used X-ray:

Radiography is the most familiar type of X-ray imaging. It is used to image mainly bones and the chest. Radiography also uses the smallest amounts of radiation.

Fluoroscopy is continuous live use of X-ray, and cane considered as a movie equivalent. The radiologist can watch the X-ray of the patient moving in real-time to watch the activity of the gut after a barium meal or intravascular contrast. Fluoroscopy uses more X-ray radiation than a standard X-ray, but the amounts are still tiny.

During Computed tomography (CT), the patient lies on a table and enters a ring-shaped scanner. A fan-shaped beam of X-rays passes through the patient into detectors placed across the patient’s body. The patient moves slowly into the machine so that a series of slices can be taken. This procedure uses the highest dose of X-rays because so many images are taken in one sitting.

The risk of X-Ray:

X-rays can cause mutations in the patient’s DNA and, therefore, might lead to cancer later in life. For this reason, X-rays are classified as a carcinogen by both the World Health Organization (WHO) and the US government. However, the benefits of X-ray technology far outweigh the potential negative consequences of using them. It is estimated that 0.4% of cancers in America are caused by CT Scan and this level is expected to rise in parallel with the increased usage of CT scans in medical procedures.

Each procedure has a different risk associated with it, depending on the type of X-ray and the part of the body being imaged. In example:

Chest X-ray is equivalent to 2.4 days of natural background radiation




Lumbar spine is equivalent to 182 days of natural background radiation




Upper gastrointestinal barium exam is equivalent to 2 years of natural background radiation




CT head is equivalent to 243 days of natural background radiation




CT abdomen is equivalent to 2.7 years of natural background radiation.

Even though the X-ray has been associated with risk of cancer, their benefit if used properly surpass their claimed danger: the importance of making the right diagnosis and choosing the correct course of treatment makes X-rays far more beneficial than they are dangerous.

Whether there is a small risk or no risk at all, the X-rays are here to stay.

Wessam Bou-Assaly is a highly experienced radiologist in Michigan with long years of practice.

What is Nuclear medicine

What is Nuclear Medicine?

Nuclear medicine refers to medications that are attached to a radioisotope (radioactive material); the drug is called a radiopharmaceutical. Several different radiopharmaceuticals are available today to study various parts of the body and treat some conditions and diseases.

The radioisotope which is attached to the drug is usually called a "tracer". The most common tracers used in nuclear medicine are thallium-201 and fludeoxyglucose (18F) (18F-FDG), gallium-67, indium-111), iodine-131, iodine-123, and technetium-99m.

The radiopharmaceutical is administered either by injection, orally (swallowing) or as an inhalation. It is designed to target a specific part of the body where there might be some abnormality or disease. The radioactive part of the drug emits gamma rays which are detected using a gamma camera. The doctor can then see what is happening inside the body.

Nuclear medicine is commonly used to evaluate the gallbladder, liver, thyroid, lungs and heart. Physiological function can be determined well using nuclear medicine, rather than anatomical detail.

Nuclear medicine can, for example, be used to identify lesions deep inside the body without having to open up with patient (surgery). It can also determine whether certain organs are working properly; it can determine whether the heart is pumping blood adequately, or whether the brain is getting enough blood, and whether the brain cells are functioning properly.

After having a heart attack, nuclear medicine procedures can help accurately assess the damage to the patient's heart.

Nuclear medicine is useful in locating the brain sites of seizures (epilepsy), Parkinson's disease and Alzheimer's disease.

Nuclear medicine can also be used to treat patients. Thousands of people with hyperthyroidism are treated every year using radioactive iodine. Certain types of cancers, as well as bone pain resulting from cancer can also be treated.

With the most advanced equipment, nuclear medicine images can be used almost simultaneously with CT scans, making detailed anatomical studies possible.

Wessam Bou-Assaly - Nuclear Medicine versus Radiology

Nuclear medicine is a sub discipline of radiology. Wessam Bou-Assaly is a radiologist who specializes in nuclear medicine. In 2007, he completed a fellowship program in nuclear medicine. He is a member of the Society of Nuclear Medicine, and he has conducted a large amount of research in the field. Nuclear medicine is different from radiology.

Radiology involves using X-ray imaging to diagnose and treat diseases, injuries, and illnesses. Radiologists use a wide array of imaging techniques including computed tomography (CT), ultrasound, MRI and X-ray radiography. These professionals create images by projecting X-rays, ultrasound waves or large magnet, over the body. Machines measure where the X-rays pass through the body, or the reflection of ultrasound waves from body organs or proton spinning characteristics when inside a strong MRI magnet to create an image of the human body.



Nuclear medicine is a type of radiology, however, it uses a very different method to create images. Professionals introduce small amounts of radioactive substances into their patients’ bodies. These substances are either injected or ingested. The radiologist will then use gamma cameras to form images based on the radiation that is emitted from the body.

Nuclear medicine is different from other types of radiological images, because the images show physiological functions. In example, radiologists can use nuclear medicine to study the flow of blood to the brain or the function of the kidneys. Other forms of radiological imaging, such as CT scans or MRI scans, only create an image.

Wessam Bou-Assaly is a radiologist who has studied neuroradiology and nuclear medicine.


Sources: http://interactive.snm.org/docs/whatisnucmed2.pdf