Chapter 23 Mammography Radiographic studies of the breast 2/21/2012

Breast Anatomy Breast =mammary gland Secondary sex characteristic Consist of glandular, fat, and fibrous tissue

Anatomy (cont’d) Base overlies pectoralis major muscles & serratus anterior Part of breast extends into axillary fossa (armpit)

Anatomy cont’d divided into 15 – 20 lobes each made up of lobules supported by Cooper’s ligament which determines firmness

Lobule size Affected by age and hormones (pregnancy) Involution: process of decreasing lobule size with age and after pregnancy = flatter, saggier breasts

Anatomy (cont’d) Axillary nodes often evaluated on mammograms Because lymphatic vessels of breast drain into: Axillary lymph nodes, laterally Internal mammary lymph nodes, medially

Tissue Variations Breasts consists of both glandular and connective Ability to visualize depends upon amount of fat within and around breast lobules- provides contrast Postpuberty breasts contain primarily dense connective tissue- harder to visualize

Mammograms comparing 2 different women 19 yr. old (never pregnant) 24 yr. old (has children)

Definition of breast cancer Cancer that forms in tissues of breast – usually in ducts (tubes that carry milk to nipple) and lobules (glands that make milk) Can men get breast cancer? Yes, but rare

Breast Cancer Ranks Nationally as the 2nd leading cause of cancer-related deaths in women What is first? lung cancer Breast cancer in United States in 2009 (estimated): New cases: 192,370 (female) Deaths: 40,170 (female)

While breast cancer is less common at a young age (i. e While breast cancer is less common at a young age (i.e., in their thirties)- Younger women tend to have more aggressive breast cancers than older women, which may explain why survival rates are lower for young women

Breast Cancer Risk increases with: Age Hormonal history early menses late menopause pregnancy after age 30 or never had a child Family history If daughter, mother, or sister has breast cancer

Mammography is the best way for early detection! Pt.s in early stages respond well to treatment Patients with advanced disease do poorly Earlier diagnosis, better chance of survival

Mammography- Risk vs. Benefit In 2007, in US – 133 deaths /million from breast cancer 5 deaths/million from mammography induced radiation (using screen film mammography) Chances are 26 times more likely that a mammogram will save you rather than harm you! More risky to refuse mammography!

What are your chances beating Breast Cancer ? Excellent if diagnosed early! If cancer is confined to breast, what is the survival rate for 5 years? 97% Incidence of breast cancer stable since 1988 -but mortality rate decreased by 29%- mainly do to early detection

At what age should a woman have her first mammogram? In November 2009, the U.S. Preventive Services Task Force (USPSTF) changed their recommendations for routine mammography screening for woman aged 40-49: USPSTF now recommends against routine screening mammography in women aged 40 to 49 years! Decision to start regular, biennial screening mammography before age of 50 years should be an individual one and take into account family history and pt's values regarding specific benefits and harms 50-74 should have mammogram every other year

American College of Radiology and Society of Breast Imaging strongly disagree! Annual screening mammography should stay at age 40! Mammography has reduced breast cancer death rate in United States by 30 percent since 1990 Based on data on performance of screening: mammography as currently practiced in US, one invasive cancer is found for every 556 mammograms performed in women in their 40s Mammography only every other year in women 50-74 would miss 19 to 33 percent of cancers that could be detected by annual screening!

Did you get your annual mammogram? In 2006: 56% of women of screening age (40 and up) reported having mammogram in past year What race of women is most likely to have had a recent mammogram? African American 68% White 62% Latino/Hispanic 59% Asian American 55%

History of breast cancer detection When was the first radical mastectomy introduced? 1898 What year was the radiographic appearance of breast cancer first reported? 1913 When did mammography became a reliable diagnostic tool? in 1950s when industrial grade x-ray film introduced

History of breast cancer detection cont’d 1960’s Xerography introduced – excellent results and much lower dose than industrial film 1975 Low- dose mammography (High speed/resolution film) introduced by DuPont- -(much lower dose- xerography discontinued)

Thermography Thermography approved by United States FDA in 1983 Detects localized temperature elevations over cancers in the breast In more than 90%, a "hot spot" will be evident if cancer is present A complement to mammography only- Can only spot superficial hot spots

MQSA (Mammography Quality Standards Act) 1992 – MQSA passed by Congress, enacted in 1994 Mammography became 1st and only federally regulated imaging exam, which mandated: Formal training and continuing education Required regular inspection of equipment Documentation of quality assurance Reporting results, follow-up, tracking pts, and monitoring outcomes

Types of Mammograms Baseline mammogram: very 1st mammogram (or 1st mammo. after surgery) Screening mammogram: all mammos after baseline- if pt. asymptomatic (no known breast problems) Diagnostic Mammogram: when woman presents with clinical evidence of: Breast disease Palpable mass or other symptom

Typical Mammography Unit Equipment is C-arm SID is fixed at 24 – 26”

Mammography Equipment Designed to produce high-contrast and high-resolution images More precise control of kVp, mA, and exposure time Low kVp : 25 – 28 AEC (automated exposure control) Grid with ratio: 4:1, or 5:1 200 lines/inch

Screen-Film Systems Now largely replaced by digital imaging Mammography cassettes contain a single screen Film is single emulsion Occasionally, extended time processing is used (reduces dose and increases contrast) Now largely replaced by digital imaging

Digital Mammography State of the art! No film or chemical processing Much better definition Compression needed about 5% less Radiation dose about 22% less Fewer repeats do to poor technique selection Images easily sent over internet Can give pt. CD of images Possible downside: if 1st digital compared to previous film mammo., can give false positives due to increased sensitivity!

Procedure Complete, careful history and physical assessment! Take notes on location of scars, palpable masses, skin abnormalities, and nipple alterations Examine previous mammograms for positioning, compression, and exposure factors

Procedure (con’t) Have Pt put on gown with opening in front Breasts must be bared for imaging Cloth will cause image artifact Remove deodorant and powder from axilla and breast It can mimic calcifications on image!

Procedure (cont’d) Explain procedure to pt., including possibility for additional projections Consider natural mobility of breast before positioning Support breast firmly so that nipple is directed forward in profile Apply proper compression Place ID markers

Compression Decreases thickness of breast- thus reduces exposure dose Decreases magnification and scatter Increases contrast Reduces motion unsharpness

Compression Device Made of firm plastic Amount of compression: between 25 and 40 pounds pressure Compression may be…. uncomfortable!

Magnification Increases visibility of small structures Uses increase OID Uses air gap Why does Radiation dose increase with magnification even though technique is not increased? -(breast is closer to source) Digital Mammography now makes “mag films” obsolete

Routine mammography projections Craniocaudal (CC) Mediolateral oblique (MLO)

Craniocaudal Projection Pt position Standing or seated facing IR holder Part position Elevate inframammary fold to maximum height Adjust IR height to inferior surface of breast Gently pull breast onto IR holder with both hands while instructing pt to press chest to IR holder

Craniocaudal Projection (cont’d) Rotate head away from breast being examined (watch out for hair!) Lean pt. toward machine Move opposite breast out of the way Place hand on shoulder and slide skin over clavicle Compress breast slowly until skin taut

Criteria for adequate Craniocaudal Projection Nipple should be in profile maximum amount of breast tissue radiographed CR – Perpendicular to base of breast Structures shown – Central, subareolar, medial fibroglandular breast tissue, pectoral muscle

Mediolateral Oblique Projection Position Center breast with nipple in profile Hold breast up and out Compress breast slowly until taut Pull down on abdominal tissue to open inframammary fold Instruct pt. to hold opposite breast laterally, out of anatomy of interest Expose on suspended respiration Release compression immediately!

Criteria for acceptable Mediolateral Oblique projection Deep and superficial breast tissues should be well separated Retroglandular fat well seen Uniform tissue exposure (adequate compression)

Other positions Mediolateral Lateromedial

Breast Implants

or behind Implants can be in front of pectoral muscle

Saline vs Silicone Silicone implants have a more natural look and feel – silicone gel texture similar to breast tissue But Silicone implant ruptures are harder to detect When silicone implants rupture, breast often looks and feels same because silicone gel may leak into surrounding areas of breast without visible difference When saline implants rupture, they deflate -results are seen almost immediately (MRI and sonography can help determine rupture or leakage)

Saline vs Silicone cont’d Replacing a ruptured silicone gel implant is more difficult than repairing saline implant Silicone implants have higher rate of capsular contracture (scarring and hardening around implant) Saline implants inflated to desired size with saline, then valve is sealed by surgeon

Radiography Of Augmented Breast (implants) Complications: Increased fibrous tissue surrounding implant (contracture) Shrinkage Hardening Leakage Pain!

Radiography Of Augmented Breast (implants) 8 projections must be obtained (2x4) (twice as many as non-implants) Four images of breast including anterior breast and implant Four images with implant displaced posteriorly into chest wall are obtained

Eklund Technique for Radiography of the Augmented Breast

What is Gynecomastia? The development of abnormally large mammary glands in males- almost entirely fat Can sometimes cause secretion of milk

Male Mammography Approximately 1000 males develop breast cancer every year Standard CC and MLO are obtained Males not screened- mammogram only if lump discovered

Treatment For Breast Cancer Lumpectomy Partial or radical mastectomy Radiation Chemotherapy (recent study shows that lumpectomy or mastectomy may be no more beneficial than radiation and chemotherapy) Lesion

Needle Localizations Used to localize breast lesions before surgery Special, open-hole plate may be used for ease of localization

Lumpectomy- Breast Specimen Radiography Imaging of lump by itself after it has been surgically excised

Breast Calcifications

Calcified Milk Ducts

Benign Cyst