1. Screening vs.diagnostic mammography
2. Conventional and digital mammography
3. Common diagnostic imaging tests for breast health concerns
4. Role of breast MRI in screening or diagnosing breast cancer
5. Role of PET scanning in screening or diagnosing breast cancer
6. Role of breast thermography in screening or diagnosing breast cancer
7. Investigation of a palpable breast lump
8. Investigation of a lesion detected by mammography
9. Dealing with uncertainty while waiting
10. Locations of diagnostic breast imaging facilities in the community
11. Resources for patients being investigated for a breast health concern

1. Screening vs. diagnostic mammography

Screening mammography involves the examination of healthy women with no known breast symptoms. Two standard x-ray views are taken of each breast. Diagnostic mammography is used to evaluate women with suspicion of breast disease either because of physical changes noted by the patient or her physician or because of abnormalities detected on a screening mammogram.

Mammograms are not 100% effective in identifying early breast cancers. They can miss up to approximately 25% of breast cancers in women aged 40-49, 15% in women 50-59 and 10% in women older than 60.¹

2. Conventional vs. digital mammography

A conventional mammogram produces images on film. A digital mammogram produces computerized images. The image can then be adjusted in several ways by the radiologist. Both mammograms are performed the same way.

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3. Common diagnostic imaging tests for investigating a breast health concern

Diagnostic mammography - Used to evaluate women with suspicion of breast disease either because of physical changes noted by the patient or her physician or because of abnormalities detected on a screening mammogram.

Breast ultrasound - Uses high frequency sound waves, which are “bounced” off the breast and converted to images on the screen. Ultrasound helps to determine if a breast abnormality is a cyst/ cystic or solid. A cyst is a fluid-filled sac, which is not cancerous. Ultrasound is not useful for routine screening of women because certain types of breast cancer are not visible by this method.

Galactogram - May be used to investigate when there is spontaneous, one-sided nipple discharge, especially when it is bloody or blood-stained. There must be active nipple discharge before this can be done. A radiologist threads a special blunt catheter into the milk duct, injects dye into it and then takes some mammographic pictures. The dye produces a visual “map” for tracing the source of the discharge and will help the doctor diagnose the problem.

Fine Wire Localization - Used to mark the location of a suspicious area in the breast that cannot be felt (non-palpable). Under mammogram or ultrasound guidance, a needle is inserted into the area of concern. The position of the needle is checked and when the radiologist is sure it is in the right place, a fine wire is inserted in the middle of the needle. The needle is removed and the wire is left in place until surgery.

Fine needle aspiration - A very thin needle is inserted into the area of concern. Ultrasound may be used to guide the needle placement. If fluid is drawn out and the suspicious area disappears, this confirms the presence of a cyst. If no fluid is withdrawn, the area may be solid and the radiologist will try to withdraw some cells to send to pathology for examination.

Stereotactic Core Biopsy - Sometimes, a suspicious area can be better located by x-ray guidance rather than ultrasound. It is often used to biopsy very small calcifications as well as other suspicious areas that cannot be biopsied under ultrasound.

Ultrasound guided core biopsy - A suspicious area is located with the use of ultrasound. Then a needle biopsy is performed to remove a small core of breast tissue for microscopic examination.

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4. Role of breast MRI in screening or diagnosing breast cancer

The use of MRI in detecting in breast cancer is based on the fact that benign lesions frequently have sparse blood flow, while malignant lesions require more blood flow. The contrast used in MRI tends to concentrate in tissues with more blood flow.²

MRI sensitivity rates for the detection of invasive breast cancer are estimated to be as high as 95-100%, which compares well to mammography at 85%. However, a significant limitation is specificity, which is highly variable ranging from 37-97%. Like all breast imaging studies, breast MRI must be correlated with other imaging findings in light of clinical findings.²

Currently, there is no level one evidence to support the use of breast MRI for any specific indication. Breast MRI has not been proven to decrease mortality, recurrence or impact of treatment. However, breast MRI can be used in a problem-solving mode only after high quality mammography and ultrasound have been carried out. As well, it should be done by a radiologist with expertise in breast MRI, as these images require specialized knowledge for interpretation.

See also the BC Cancer Agency Breast Tumour Group's clinical indications for breast MRI (Magnetic Resonance Imaging).

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5. Role of PET scanning in screening or diagnosing breast cancer

Positron emission tomography (PET) involves the intravenous injection of small doses of radio-labelled glucose, followed by a scan. This creates an image of the extent of cancer in the body. Cells in the body that have a high metabolic rate concentrate glucose and show up as a dark spot on the scan. Many invasive cancers are rapidly growing compared to other tissues and show up as "hot" spots. However, to be visible on the scan, cancer tumours generally have to be larger than half a centimetre.

Microcalcifications or individual cancer cells do not show up on a PET scan. Not all cancers, even when large, show up on scanning. Low grade, slow growing cancers are especially likely not to show up.³

Presently, PET scanning may be helpful in assessing if a tumour is still present after chemotherapy and radiation therapy; whether cancer has spread to the lymph nodes; or determining the extent of metastatic breast cancer. Research into PET scanning's use in breast cancer care is ongoing.

6. Role of breast thermography in screening or diagnosing breast cancer

Thermography measures heat patterns in the breast by using infrared detectors to record on film hot and cold areas of the body. In theory, long before a breast lump forms, there is greater blood flow and an increase in temperature at the site. Detecting that activity can provide a warning of future problems. However, in the screening of asymptomatic women, breast thermography does not approach the sensitivity or the specificity of mammography and cannot be recommended at the present time as the screening method.⁴

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7. Investigation of a palpable breast lump

• Investigation of women with a breast lump or suspicious change in breast texture starts with a history, physical examination and usually mammography
• The clinical history should establish how long the lump has been noted, whether any change has been observed and whether there is a history of biopsy or breast cancer
• Risk factors for breast cancer should be noted, but their presence or absence should not influence the decision to investigate a lump further
• The physical examination of the breast should aim to identify those features that distinguish malignant from benign lumps
• Mammography can often clarify the nature of the lump and detect clinically occult lesions in either breast
• Fine-needle aspiration can establish whether the lump is solid or cystic. When a tumour is solid, cells can be obtained for cytologic examination
• Ultrasonography is an alternative method to fine-needle aspiration for distinguishing a cyst from a solid tumour
• Whenever reasonable doubt remains as to whether a lump is benign or malignant, a biopsy should be carried out
• When surgical biopsy is used, the aim is to remove the whole lump in one piece along with a surrounding cuff of normal tissue
• Core biopsy, either clinically or image-guided, can usually establish or exclude malignancy, thus reducing the need for surgical biopsy
• Thermography and light scanning are not recommended diagnostic procedures. The value of magnetic resonance imaging is still under investigation. It is not a routine diagnostic procedure at this time
• The choice of procedure should take into account the experience of the diagnostician and availability of the technology in question
• The work-up should be completed expeditiously and the patient kept fully informed throughout
• Even when malignancy is not found, it might be wise, in some cases, to arrange followup surveillance⁵

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8. Investigation of a lesion detected by mammography

• When an abnormality is detected on screening mammography, clinical evaluation and thorough radiologic work-up are needed to determine its significance
• Clinical evaluation should include a history and a thorough examination of the breast, axilla and supraclavicular areas
• In the radiologic work-up, diagnostic mammograms should be obtained with additional views, spot compression and magnification views as appropriate
• Current mammograms should be compared with any previous mammograms
• The mammographic report should include a precise description of the abnormal features visualized and an estimate of the level of suspicion of cancer they imply
• Whenever there is any doubt in the interpretation of mammograms, the interpretation of two experienced readers should be obtained. Ultrasonography can be used to clarify the nature of noncalcified nodular lesions
• Management decisions require close communication between the woman and her physicians. Throughout, a clinician should be identified who will coordinate and transmit all decisions. Management will depend on the estimated level of risk

The following radiologic classification into four categories is suggested:

1. Benign, not due to cancer
2. Low risk, probability of cancer under 2%
3. Intermediate risk, probability of cancer 2% to 10%
4. High risk, probability of cancer over 10%

• Category 1 abnormalities require no further investigation
• Category 2 abnormalities may be followed up by periodic mammographic and clinical examinations. Follow-up examination of category 2 abnormalities should be carried out at approximately six and 12 months. If the abnormality is stable, examination should be repeated annually for two to three years thereafter. The rationale of follow-up should be explained, and women should be made aware that it is not possible to provide complete assurance that an abnormality is benign
• Category 3 abnormalities usually require image-guided fine-needle or core biopsy. Every image-guided needle biopsy should be accompanied by a full report
• Category 4 abnormalities should usually be excised. This may be preceded by image-guided needle biopsy. When surgical biopsy is carried out, the margins of the resected specimen must be free of tumour. The intact pathology specimen should be examined radiographically to confirm that all mammographic abnormalities have been removed
• The patient should be kept fully informed as to the reason for each test and the meaning of its results. The process, from initial detection of the mammographic abnormality to the final management decision, should be completed as rapidly as possible ⁶

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9. Dealing with uncertainty while waiting

• At the time of the test, patients can ask when and how they will be told about their test results. This will prepare them for how long they will have to wait to get their test results
• Keep doing all the everyday things. Following a routine and keeping busy gives patients other things to think about and helps to pass the time
• Pay attention to self-care. Often, good health habits are neglected during stressful times. This will lower energy levels as well as a sense of well-being. Bodies need energy to help cope with stress
• Eat a well balanced diet
• Get a good night’s sleep
• Avoid excessive amounts of caffeine and alcohol which interfere with sleep
• Walk. Exercise or physical activity may help with relaxation
• Take a long relaxing bath or meditate. Do whatever helps with relaxation
• Talk about what’s happening. Who to talk to and what to say is a personal decision. Family, close friends and colleagues are all people to turn to and talk about what they are going through. This support could be very helpful. Sometimes, women decide not to talk to others because they don’t want them to worry. When they are making this decision, it might help to think about what they would like family and friends to do if they were having the same tests done
• Talk to others who have had tests for a screening abnormality or a change in their breast. Others may know someone or a friend or family member might know someone – give them a call!
• Consider having someone go with them to their appointments. It’s hard to remember all the details of new experiences and new information, especially when you are very anxious. A second pair of eyes and ears will help. Having the support of someone who knows and cares about them is helpful
• Talk to their family doctor. Give the office a call and describe feelings and concerns. The family doctor may be able to help during this anxious time⁷

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10. Locations of diagnostic breast imaging facilities in the community

In order to access diagnostic breast imaging services, even for routine mammography following a breast cancer diagnosis, patients need to be referred by a physician. Therefore, the best way to locate diagnostic breast imaging services in their community is to contact their family doctor or surgeon. Often, these services are offered in acute care hospitals, so contacting their nearest hospital can also provide some information on services offered.

11. Resources for patients who are being investigated for a breast health concerns

• A Woman's Guide to Breast Assessment - this booklet, developed by Cancer Care Ontario, was designed for those who have recently had a screening abnormality or a change in their breast.

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REFERENCES

1. Olivotto I, Gelmon K, McCready D, Pritchard K, Kuusk U. Intelligent patient guide to breast cancer. 4th ed. Edwards C, editor. Vancouver (B.C.): Intelligent Patient Guide Limited; 2006, pg.35

2. Harris JR, Lippman ME, Morrow M, Osbourne CK. Diseases of the breast. 3rd ed. Philadelphia, PA. Lippincott Williams & Wilkins; 2004, pg.122-123.

3. Olivotto I, Gelmon K, McCready D, Pritchard K, Kuusk U. Intelligent patient guide to breast cancer. 4th ed. Edwards C, editor. Vancouver (B.C.): Intelligent Patient Guide Limited; 2006, pg.49-50.

4. BC Cancer Agency (http://www.bccancer.bc.ca). Vancouver (BC): 2006. (cited Oct 25, 2006). Available from: [link to be added]

5. Clinical practice guidelines for the care and treatment of breast cancer, Guideline 1: The palpable breast lump: information and recommendations to assist decision-making when a breast lump is detected, February 10, 1998, © 2006 CMA Media Inc. or its licensors.

6. Clinical practice guidelines for the care and treatment of breast cancer, Guideline 2: Investigation of lesions detected by mammography, February 10, 1998, © 2006 CMA Media Inc. or its licensors.

7. Breast Assessment Regional Coordinating Committee and Community Breast Assessment Committee, Cancer Care Ontario, Southwest and South Regions. A woman's guide to breast assessment. Paris, ON. Thompson Printing; August 2002, pg. 23.