LO1 1.2 - Anatomy, Physiology, and Pathology of the Breast

Where does the breast tissue extend?

Covers the pectoralis major, from 2-3 rib to 6-7 rib and ALL the way back to the chest wall. From the lateral edge of the sternum or the anterior axillary (armpit region)

What is the axillary tail?

the natural expansion of breast tissue to the axillary fossa

What portion of the breast is mobile vs fixed?

lateral inferior aspects are mobile, medial and superior aspects are fixed

How do lobules change with age and pregnancy?

decrease and size, in a process called involution

What are the 2 key ways to describe location of structures or lesions in the breast

Quadrant or Clock method

quadrants: upper, lower vs inner, outer

How do cooper’s ligaments change with age?

Coopers or suspensory ligaments hold the breast upright, overtime they loose function causing the breast to naturally sag

Which direction does the breast drain lymph?

laterally into axillary lymph nodes

How many Lactiferous ductulus do the breasts contain?

15 to 20, 1 for each lobule

What is normal breast anatomy?

Where does the majority of breast cancer start?

ducts

Where is most commonly the first place cancer cells spread to from the breast?

the axillary lymph nodes

How many views should a lesion be visualized?

2

what are the characteristics visualized in a breast mass?

size, location, tissue density, shape, characteristics (smooth vs spiculated), growth time/interval changes

Where do most breast cancers occur?

upper outer quadrant (between 9 and 12)

How is size used when describing breast masses?

only a description, does not have any indication on malignancy

How is tissue density used to analyze breast masses?

mostly fat - benign

variable fibro glandular tissue - suspicious

some cysts appear bright but are malignant

How is shape used to analyze breast masses?

smooth, oval, or gently lobulated - benign

irregular/spiculated - suspicious

What are margin characteristics? how are they used to analyze breast masses?

well defined/well circumscribed - benign

microlobulized - 50% malignant

obscured, or ill defined margins - suspicous

What is done when mass can only be visualized on one view?

spot compressions to separate it from superimposed breast tissue

What precent of microcalcifications in asymptomatic women are cancerous?

15-25%

How are microcalcifications best defined when imaging?

magnification projections

What are the characteristics of benign calcifications?

moderate size

scattered location

occur bilaterally (on both breasts)

round in shape

What are the characteristics of malignant masses?

poorly defined

irregular margins

spiculated (star like)

What is the most common kind of breast cancer?

ductal carcinoma

(90% of all situ, 70% of invasive)

What is Lobular carcinoma?

abnormal cells in lobules AKA the milk producing glands

Starts in breast

What is Ductal Carcinoma?

cancer of the milk ducts, may become invasive and spread from walls of ducts and spread throughout breast and body

what % of women diagnosed with early stage breast cancer later develop metastatic disease?

30%

Can men get breast cancer?

yes

what is BI-RADS score?

a way to report radiologic findings consistently, a standardized score between radiologists to report results

What are the BI-RADS categories? (0-6)

0: incomplete AKA needs more info like ultrasound or magnification views

1: negative

2: benign findings

3: probably benign (needs short-term interval follow up)

4: suspicious abnormality (A,B,C rating) - biopsy recommended

5: high suggestion of malignancy (95% malignancy)

6: Proven malignancy via biopsy

What are the 4 breast composition categories?

1: almost entirely fat

2: scatter fibro-glandular densities

3: heterogenous density (very dense)

4: extremely dense

a gets higher images become harder to report on and identify masses

How are the level 4 ABC BI-RADS scores scaled for probability of malginancy?

4a. 2-10% chance

4b. 10-50% chance

4c. 50-95% chance

what is CAD?

computer aided diagnosis - utilize algorithms/AI

Second read/second set of eyes

How much has CAD increased the chance of cancer detection?

5-15%

How does dense breast tissue change chance of cancer?

higher risk

Can breast tissue type be determined by look or feel of breasts externally?

no

What is adenocarcinoma?

term for breast cancer that begins in glandular/secreting tissue (ducts or lobes)

what does carcinoma in situ mean?

cancer cells that have not yet spread to surrounding tissue (noninvasive)

what is fibroadenoma of the breast?

benign breast lump of fibrous and glandular tissue, shrink and go away without treatment

what are fibrocystic breast?

bumpy or rope like textured tissue, may cause general tenderness or pain. Changes in size with menstrual cycle and may appear with both breast

How to interpret clock localization system on a mammogram?