Breast Ca

Question 1

def of breast Ca?

Answer 1

cancer within the breast tissue, typically invading past the basement membrane

ductal carcinoma – more common
lobular carcinoma – less common

Question 2

RF for breast Ca?

Answer 2

• fhx of breast cancer
• personal hx of breast ca
• brca1/2 mutation or other genetic mutations (TP53)
• nulliparity
• early menarche or late menopause
• dense breasts
• exogenous hormone therapy – OCP, hormone replacement therapy
• obesity
• alcohol
• exposure to ionizing radiation to the chest

Question 3

who gets breast ca the most?

Answer 3

females
~95% occur in women >40Y

median age at dx is 61Y

Question 4

explain EP, PR, and HER2 of breast cancers

Answer 4

some breast cancers have overexpress hormone receptors which helps them grow
- estrogen receptor (ER)
- progesterone receptor (PR)

some breast cancers release a protein called HER2 which helps the cancer grow and spread more aggressively
- HER2+

Question 5

why does being triple negative in breast cancer mean you have a worse prognosis?

Answer 5

it means there are less therapies that can be used to tx the cancer

as many of the therapies use some method of hormone depletion to help starve the tumour

so not having targets decreases the available therapies

Question 6

what kind of s/s are you expecting for breast ca?

Answer 6

• nipple discharge
• nodules - firm, fixed, irregular boarders, nontender
• skin changes - peau d’orange, dimpling, rashes/redness, scaling, skin thickening
• nipple inversion
• axillary edema
• constitutional s/s

Question 7

what are common sites of mets?

Answer 7

LN
lungs
liver
bone
brain

Question 8

what ix would you order for a suspected breast ca?

Answer 8

1. imaging (>30Y mammo then u/s if concerning; straight to u/s for <30Y)
2. biopsy
3. HER2 and ER and PR testing
4. baseline labs (CBC with diff, Cr, Urea, electrolytes, ALT/ALP, bilirubin, albumin) + baseline CEA
5. imaging based on associated s/s for potential mets (CT/MRI/XR)
6. tumour marker: CA15-3 (breast cancer specific) – good to determine if there is metastatic BCa

Question 9

how would you tx breast cancer?

Answer 9

early stage – refer to surg onc for resection

consider adjuvant therapy: external beam radiation, chemotherapy, HER2 therapy (herceptin), and hormone therapy (tamoxifen or aromatase inhibitors)

chemotherapy: antitumour abx, antimetabolite, or MT inhibitor

Question 10

what therapy option do we have if they are HER2+?

Answer 10

herceptin - mab

Question 11

what therapy option do we have if they are ER or PR+?

Answer 11

tamoxifen - for both pre and postmenopausal

aromatase inhibitor - for postmenopausal

Question 12

walk me through the breast cancer screening guidelines?

Answer 12

• average risk: mammograms for 50-74Y every 2Y
• high risk (fhx or phx or known mut): 30-69Y → mammogram and breast MRI every year

Question 13

what tumour marker can we use for breast cancer?

Answer 13

CA15-3