Mammography Flashcards
Breast cancer Statistics
- most common cancer among Canadian women (excluding non-melanoma skin cancers)
- 2nd leading cause of death from cancer for Canadian women
Mammography
used for DETECTION
diagnosis- confirmed by a pathologist
Anatomy of the breast
- fibrous, glandular, adipose
- Muscles – pectoralis major and serratus anterior
- Axillary tail
- Lobes 15-20
- Cooper’s Ligaments (fibrous)
- Lymphatic vessels
Breast tissue
- constantly changing with monthly and life cycles
Glandular
most sensitive to radiation, cancer arises from this type
Distribution changes with hormones, drugs, ageing
Somewhat determined by genetics
Fibrous
semi-elastic
Fat
atrophy of glandular tissue
Breast tissue categories
Three categories:
Fibro-glandular – young breast, pregnant or lactating
Fibro-fatty – more equal distribution of glandular and fat, usually 30-50 year olds
Fatty – post menopause 50+, males
Soft Tissue Radiography
mainly muscle and fat
very little subject contrast so we use a low kV to increase contrast
promote photoelectric effect
compress the breast to decrease the Compton effect
NS Breast Screening Guidelines
Age 40-49 annual screening recommended
Age 50-74 screening at two-year intervals (or annually if higher risk)
Age 75 and older – continue screening if in good health
May be referred for diagnostic imaging by a physician if symptomatic, regardless of age, sex
Breast imaging preparation
No deodorant or lotions Hospital gown No caffeine (could increase breast tenderness)
Breast Imaging: History
Scheduling of appointment Age Previous mammogram Screening or diagnostic # of pregnancies, breast feeding Hormone therapy First/last menstrual period Birth control
Compression
25-40 lbs of force Decreases part thickness Decreases scatter Decreases exposure Increases contrast Reduces motion Reduces superimposition Improves object/IR contact
Augmented Breast
The rate of cancer detection is lower Complications include: Increased fibrous tissue surrounding the implant Hardening Rupture Pain
Augmented breast: imaging
- Routine 2 images per breast is incomplete
- Suggested 4 images per breast
- CC, MLO demonstrates posterior and superior aspects
- Eklund technique CC and MLO will displace implant (extra views)
- Exposure factors will be significantly different (AEC not recommended)
- US and MRI are frequently used
Male Breast Mammography
- Incidence is about 1% of breast cancers
- Mammography often indicated by gynecomastia
- Routine CC and MLO or reverse projections, CC and LMO
Other Modalities
Ultrasound
- If there is a palpable mass and the mammo shows dense glandular tissue or smooth outline, non-palpable mass
- Can be used as a guide for biopsy
MRI
-when breast tissue is dense, fibrocystic or for implants
Nuclear Medicine Sentinel node studies PET metabolism of FDG, metastatic disease PET/CT or CT
Breast cancer- risk factors
Female Age Family/personal history Early menarche Late menopause No pregnancy, pregnancy after 30 BRCA1, BRCA2 Radiation exposure Dense breasts Oral contraceptives Alcohol consumption Obesity post-menopause
NO LINK TO BREAST CANCER: Deodorant/antiperspirants Abortion Breast implants Bras
Breast Pathology- inflammatory
- Mastitis
- duct ectasia
- common in women who breast feed
breast pathology- benign
Fibrocystic changes Cysts Fibroadenoma Hyperplasia Scarring Gynecomastia
breast pathology- malignant lesions
Noninvasive lesions Ductal Carcinoma in situ Precursor to invasive breast Ca Heterogenous group of lesions Often detected as microcalification clusters Lobular carcinoma in situ
Invasive lesions
Cross wall and invade adjacent tissues
IDC, ILC, Inflammatory BC, Paget disease of the nipple
Pathology Detection
Standard CC and MLO views Coned magnification views using cone shaped compression device Other projections Tomography Ultrasound
Radiologist reporting
BI-RADs:
lesions: 1-6 ; 5= almost positive
breast density: A-D
dense breasts can obscure pathology on images
core biopsy
Stereotactic
The computer calculates lesion location and adjusts needle angle and depth
Comparable to surgical biopsy
Needle localization
Wire localization
Prior to surgical biopsy
Used as a guide
Specimen removed and imaged
Tumor Staging
- tumor size
- node involvement
- metastatic spread
Breast cancer: treatment
Surgery
Radiation
Chemotherapy
Hormone therapy
Radiographic Markers
lump marker- palpable lump; triangle marker
nipple marker- bead
mole marker- circle
scar marker- dotted line
Craniocaudal positioning
Patient faces machine Head turned to the contralateral side Tissue pulled away from the chest wall Compression applied Suspended breathing
Craniocaudal Evaluation criteria
Nipple in profile
Central, subareolar and medial portion of breast visualized
No wrinkles
No motion
Pectoral muscle visualized on 20-30% of patients
Mediolateral Oblique: Positioning
Demonstrates upper outer quadrant and axillary tail
Tissue pulled anterior and medially so lateral portion of the breast is against IR
Nipple in profile
Compression is below the humeral head, in front of clavicle
MLO: evaluation criteria
No motion No wrinkles Nipple in profile Tissue visualized from pectoral muscle to nipple No “camel nose” Inframammary fold must be seen
Galactogram
- injection of contrast via nipple
