The BREAST
Sara Sukumar
Pathobiology,
September 6, 2013
1
Breast Cancer
Breast cancer is second only to lung cancer as
a cause of cancer deaths in American women
• One out of every eight women
will be diagnosed with breast
cancer in 2011
• Fortunately, radical mastectomy
(surgical removal) is rarely
needed today with better
treatment options
2
Trends since 1950 in
age-standardized
death rates
comparing breast and
selected other types
of cancer, among
women in the USA
EBCTCG, Lancet, 2010
BREAST CANCER IN THE WORLD
 1.15 million new cases
 Incidence increasing in most
countries
 470 000 deaths
 Half of the global burden in lowand medium-resourced countries
Outline- Part 1
• Development of the Breast
• Female Breast Anatomy
• Breast Cancer
• Risk Factors- Sporadic and
Hereditary Breast Cancer
• Biology of Breast Cancer
5
Outline- Part 2
• How breast cancer is:
• Detected
• Diagnosed
• Treated
6
Development of the Breast Ductal Tree
Occurs mainly after birth
Female Breast Anatomy
• The bulk of the breast
tissue is adipose tissue
interspersed with
connective tissue
• Breast ducts comprise
only about 10% of the
breast mass
– lobes
– ducts
– lymph nodes
8
Stucture of the Breast
• Breast has no
muscle tissue
• There are muscles
underneath the
breasts separating
them from the ribs
9
Breast Gland
• Each breast has 8 to 10
sections (lobes) arranged
like the petals of daisy
• Inside each lobe are many
smaller structures called
lobules
• At the end of each lobule
are tiny sacs (bulbs) that
can produce milk
10
Ducts
• Lobes, Lobules and bulbs,
are linked by a network of
thin tubes (ducts)
Duct
Areola
• Ducts carry milk from
bulbs toward dark area of
skin in the center of the
breast (areola)
Ducts join together into larger ducts ending at
the nipple, where milk is delivered
11
Breast development-Adult
Intralobular stroma
• 4A: Premenopausal adult breast
section (H and E) showing a
terminal duct (td) entering a
TDLU. ils: intralobular stroma; iels:
interepithelial lobular stroma
• 4B: High power of A.
• 4C: Intralobar stroma reactive
antibody
• 4D: Increase in number of lobules
with loss of fat, still separated by
intralobular connective tissue
• 4E: Lactating mammary gland
composed of dilated acini
containing milk
• 4F: Following weaning, involution
occurs. The two layered
epithelium of the resting breast is
reformed in cycles of pregnancy
and lactation
• 4G, H: Virginal hypertrophy
Breast development- Involution, and
benign breast conditions
Postmenopausal breast- both lobules and
ducts are reduced in number. Intralobular
stroma is replaced with collagen
•5A: Few acini and ducts remain,
embedded in thin strands of collagen,
widely dispersed in the fat. Connective
tissue regresses, replaced by fat
Benign breast conditions•5B:Cysts containing secretions
•5C: Apocrine metaplasia-lining epithelium
takes on features of apocrine glands of the
axilla. Granular cytoplasm, large nuclei,
nucleoli.
•5D:Sclerosing adenosis-lobular
proliferation with acini are infiltrative at the
margins
•5F: Epithelial hyperplasia-expansion of
lobules
Blood Vessels
Oxygen, nutrients, and other
life-sustaining nourishment
are delivered to breast tissue
by the blood in the arteries
and capillaries.
14
Lymphatic System
Lymph node
Lymph duct
A network of vessels
• Lymph ducts: Drain fluid
that carries white blood
cells (that fight disease)
from the breast tissues
into lymph nodes under
the armpit and behind
the breastbone
• Lymph nodes: Filter
harmful bacteria and
play a key role in
fighting off infection
15
Three Types of Vessels
1
Lobules
Ducts
Nipple
Milk
3
Lymph
Nodes
Bacteria
Lymph
Vessels
2
Blood
Vessels
Cell life
16
Signs and Symptoms
Most common:
lump or
thickening in
breast. Often
painless
Discharge
or
bleeding
Change in size
or contours of
breast
Redness or pitting
of skin over the
breast, like the
skin of an orange
Change in color
or appearance
of areola
17
Noncancerous Conditions (1)
• Fibrocystic changes: Lumpiness, thickening and
swelling, often associated with a woman’s period
• Cysts: Fluid-filled lumps can range from very tiny
to about the size of an egg
• Fibroadenomas: A solid, round, rubbery lump that
moves under skin when touched, occuring most in
young women
• Infections: The breast will likely be red, warm,
tender and lumpy
• Trauma: a blow to the breast or a bruise can cause
a lump
3/12/2016
18
Noncancerous Conditions (2)
• Microcalcifications: Tiny deposits of calcium
can appear anywhere in a breast and often
show up on a mammogram
– Most women have one or more areas of
microcalcifications of various sizes
– Majority of calcium deposits are harmless
– A small percentage may be precancerous or cancer
(biopsy is sometimes recommended)
19
Causes
• Some of the cells begin growing abnormally
• These cells divide more rapidly than healthy
cells do and may spread through the breast,
to the lymph or to other parts of the body
(metastasize)
• The most common type of breast cancer
begins in the milk-production ducts, but
cancer may also occur in the lobules or in
other breast tissue
3/12/2016
20
Normal Breast
Breast profile
A ducts
B lobules
C dilated section of duct to hold milk
D nipple
E fat
F pectoralis major muscle
G chest wall/rib cage
Enlargement
A
normal duct cells
B
basement membrane (duct wall)
C lumen (center of duct)
Illustration © Mary K. Bryson
21
Ductal Carcinoma in situ (DCIS)
Ductal
cancer
cells
Normal
ductal
cell
22
Illustration © Mary K. Bryson
Invasive Ductal Carcinoma (IDC
– 80% of breast cancer)
Ductal cancer
cells breaking
through the
wall
• The cancer has spread to the
surrounding tissues
• Carcinoma refers to any cancer
that begins in the skin or other
tissues that cover internal
organs
Illustration © Mary K. Bryson
23
Range of
Ductal
Carcinoma in
situ (DCIS)
24
Invasive Lobular Carcinoma (ILC)
Lobular cancer
cells breaking
through the
wall
Illustration © Mary K. Bryson
25
Cancer Can also Invade Lymph or Blood
Vessels-Metastatic breast cancer
Cancer cells
invade
lymph duct
Cancer cells
invade
blood vessel
Illustration © Mary K. Bryson
26
Factors determining risk
of developing Breast
Cancer
27
Breast Cancer Risk Factors
unalterable factors
Age
Family/Personal
History
GENDER - All
women are
at risk
Race
Treatment with
DES
Radiation
Reproductive
History
Menstrual
History
Genetic
Factors
Breast Cancer Risk Factors
that can be controlled
Obesity
All
women are
at risk
Exercise
Breastfeeding
Alcohol
Not having
children
Birth Control
Pills
Hormone
Replacement
Therapy
Potential Applications for
Breast Cancer Biology
• Predict risk of cancer development
• Estimate prognosis for established
cancer
• Predict response to therapy
• Identify therapeutic targets
• Identify early detection markers
Family history as a risk factor-
Hereditary Breast and Ovarian Cancer
15%-20%
5%–10%
Breast Cancer
5%–10%
Ovarian Cancer
Sporadic
Family clusters
Hereditary
Causes of Hereditary
Susceptibility to Breast Cancer
5 to 10% of breast cancers can be attributed to inherited factors
Gene
Contribution to
Hereditary Breast
Cancer
BRCA1
20%–40%
BRCA2
10%–30%
TP53
<1%
PTEN
<1%
Undiscovered genes
30%–70%
* Li-Fraumeni Syndrome, abnormal TP53 gene on
chromosome 17p, associated with premenopausal
breast cancer, childhood sarcomas, brain tumors,
leukemia, and adrenocortical adenomas
*Cowden’s Syndrome, abnormal PTEN tumor
suppressor gene on chromosome 10 associated
with premenopausal breast cancers,
gastrointestinal malignancies, and benign and
malignant
Features That Indicate Increased
Likelihood of Having BRCA Mutations
• Multiple cases of early onset breast cancer
• Ovarian cancer (with family history of
breast or ovarian cancer)
• Breast and ovarian cancer in the same
woman
• Bilateral breast cancer
• Ashkenazi Jewish heritage
• Male breast cancer
BRCA1-Associated Cancers:
Lifetime Risk
Breast cancer 50%-85%
(often early age at onset, less than 40
years)
Second primary breast cancer 40%-60%
Ovarian cancer 15%-45%
Possible increased risk of other
cancers (e.g. prostate, colon)
BRCA2-Associated Cancers:
Lifetime Risk
breast cancer
(50%-85%)
male breast cancer
ovarian cancer
(6%)
(10%-20%)
Increased risk of prostate,
laryngeal, and pancreatic
cancers (magnitude unknown)
Comparing Breast Cancer Risk Estimates in
BRCA Mutation Carriers
100
BRCA1+ carriers
(BCLC)
80
Breast
cancer 60
risk (%)
BRCA1+
carriers
(Ashkenazi
Jews)
40
20
General population
0
40
50
60
Easton DF et al. Am J Hum Genet 56:265, 1995
Struewing JP et al. N Engl J Med 336:1401, 1997
70
80
Age
Established Prognostic Markers for
Breast Cancer
•Axillary lymph nodes
•Tumor size
•Histological grade
•Histological tumor type
•Steroid receptor status
•Age
•
NIH Consensus Conference 2000
Potential Applications for
Breast Cancer Biology
• Predict risk of cancer development
• Estimate prognosis for established
cancer
• Predict response to therapy
• Identify therapeutic targets
• Identify early detection markers
Molecular Portrait of Breast Cancers
Basallike
HER-2
Sorlie T et al, PNAS 2001
“Normal”
Luminal
B
Luminal
A
Subtypes and Prognosis
Sorlie T et al, PNAS 2001
Potential Applications for
Breast Cancer Biology
• Predict risk of cancer development
• Estimate prognosis for established
cancer
• Predict response to therapy
• Identify therapeutic targets
• Identify early detection markers
Common molecular alterations in
breast cancer
• Mutations- Very rare compared to colon ca.
• PI3KCA single point mutations, insertions, frame shifts25-30%
• p53- Around 15-25%; 50% inclusive of intronic
mutations
• Other genes with less than 5% incidence of mutations
• Overexpression of oncogenes- by amplification or
transcriptional deregulation ex. Myc, HOXs, syk, TKs
• Loss of expression of tumor suppressor genes- by
deletion, or methylation of promoter sequences
• microRNAs and long noncoding RNAs- emerging players
The Estrogen Receptors
2 cys-rich zinc fingers
Recognize EREs, and stabilize Variable
Tx activation Hinge region
domain
Activation of Estrogen Receptor
JM Hall et al, JBC
Her-2 overexpression in breast
cancer- 1985-1998
•
•
•
•
About 20-30% of breast cancers overexpress
HER-2 protein (usually because of gene
amplification)
Monotherapy with anti-HER-2 monoclonal antibody
(trastuzumab or Herceptin) has a 30% response
rate in HER-2-positive metastatic breast cancer
Combination of trastuzumab plus chemotherapy
improves time to progression and overall survival in
advanced HER-2 positive breast cancer
Trastuzumab plus anthracycline results in a 20%
incidence of cardiotoxicity
Potential Applications for
Breast Cancer Biology
• Predict risk of cancer development
• Estimate prognosis for established
cancer
• Predict response to therapy
• Identify therapeutic targets
• Identify early detection markers
The EGFR (ErbB) family and ligands
EGF
TGFa
Amphiregulin
b-cellulin
HB-EGF
Epiregulin
Tyrosine kinase
domain
Heregulins
NRG2
NRG3
Heregulins
b-cellulin
100
44
36
48
100
82
59
79
100
33
24
28
ErbB-1
Her1
EGFR
ErbB-2
Her2
neu
ErbB-3
Her3
Cysteine-rich
domains
C-terminus
ErbB-4
Her4
www.astrazeneca.com
The dual ErbB-1 (EGFR) and ErbB-2 tyrosine
kinase inhibitor lapatinib kills MDA-MB-361 and
MCF7 human breast cancer cells better than
trastuzumab.
Slamon, D. J. Oncologist 2004;9(Suppl 3):1-3
Copyright ©2004 AlphaMed Press
Applications of Expression Microarrays
in Predicting Response to Therapy
• Different profile of sporadic vs hereditary breast
cancer (Heldenfalk, NEJM 2001)
• Identify subset of young women with poor prognosis early
breast cancer (van’t Veer, Nature 2002)
• Subset outcomes for women with node-negative
ER-positive breast cancer treated with
tamoxifen (Paik, NEJM 2004, SABCS 2004)
So What Good is All this Molecular Analysis??
Now available--$3400
Should we use it?
For whom?
How?
Candidate Gene Selection
From ~40,000 genes
250
cancer-related
candidate genes
*Sources include:
1) Van 't Veer et al, Nature 415:530, 2002
2) Sorlie et al, Proc. Natl. Acad. Sci. USA 98:10869,
3) Ramaswamy et al, Nature Genetics 33:4, 2003
Paik etet
al,al,
SABCS
2003 Res. 61:5979, 2001
4) Gruvberger
Cancer
Three Breast Cancer Studies Used to Select 16
Cancer and 5 Reference Genes
PROLIFERATION
Ki-67
STK15
Survivin
Cyclin B1
MYBL2
HER2
GRB7
HER2
GSTM1
INVASION
Stromelysin 3
Cathepsin L2
CD68
Best RT-PCR performance
and most robust predictors
BAG1
Paik et al NEJM 2004
ESTROGEN
ER
PGR
Bcl2
SCUBE2
REFERENCE
Beta-actin
GAPDH
RPLPO
GUS
TFRC
Three Breast Cancer Studies Used to
Develop Recurrence Score (RS) Algorithm
RS = + 0.47 x HER2 Group Score
- 0.34 x ER Group Score
+ 1.04 x Proliferation Group Score
+ 0.10 x Invasion Group Score
+ 0.05 x CD68
- 0.08 x GSTM1
- 0.07 x BAG1
Recurrence
Category
Low risk
Intermediate risk
High risk
RS (0 – 100)
< 18
18 – 30
≥ 31
Paik et al, SABCS 2003
Low recurrence score means:
Clear benefit from tamoxifen
No benefit from chemotherapy
1.0
T CT
P
0.8
DRFS
0.6
0.4
0.2
Placebo (B14)
Tam (B14)
Tam (B20)
Tam + Chemo (B20)
N
355
668
227
424
2
4
0.0
0
6
Years
Paik, SABCS, 2004
8
10
Intermediate recurrence score means:
Clear benefit from tamoxifen
Uncertain benefit from chemotherapy
1.0
T CT
0.8
P
DRFS
0.6
0.4
0.2
Placebo (B14)
Tam (B14)
Tam (B20)
Tam + Chemo (B20)
N
355
668
227
424
2
4
0.0
0
6
Years
Paik, SABCS, 2004
8
10
High recurrence score means:
No benefit from tamoxifen
Clear benefit from chemotherapy
1.0
CT
0.8
P T
DRFS
0.6
0.4
0.2
Placebo (B14)
Tam (B14)
Tam (B20)
Tam + Chemo (B20)
N
355
668
227
424
2
4
0.0
0
6
Years
Paik, SABCS, 2004
8
10
Potential Applications for
Breast Cancer Biology
• Predict risk of cancer development
• Estimate prognosis for established
cancer
• Predict response to therapy
• Identify therapeutic targets
Outline- Part 2
• How is breast cancer:
• Detected
• Diagnosed
• Treated
59
Mammography
• Use a low-dose x-ray system to examine breasts
• Digital mammography replaces x-ray film by
solid-state detectors that convert x-rays into
electrical signals. These signals are used to
produce images that can be displayed on a
computer screen (similar to digital cameras)
• Mammography can show changes in the breast up
to two years before a physician can feel them
60
Mammography Equipment
61
Computer-Aided Diagnosis
• Mammography allows for efficient diagnosis
of breast cancers at an earlier stage
• Radiologists misdiagnose 10-30% of the
malignant cases
• Of the cases sent for surgical biopsy,
only 10-20% are actually malignant
• CAD systems can assist radiologists to
reduce the above problems
National Cancer Institute
62
What Mammograms Show
Two of the most important mammographic
indicators of breat cancers
– Masses
– Microcalcifications: Tiny flecks of calcium – like
grains of salt – in the soft tissue of the breast that
can sometimes indicate an early cancer.
63
Detection of Malignant Masses
Malignant masses have a more spiculated
appearance
malignant
benign
64
Mammogram – Difficult Case*
• Heterogeneously dense breast
• Cancer can be difficult to
detect with this type of
breast tissue
• The fibroglandular tissue
(white areas) may hide the
tumor
• The breasts of younger
women contain more glands
and ligaments resulting in
dense breast tissue
65
Mammogram – Easier Case*
• With age, breast tissue
becomes fattier and has
fewer glands
• Cancer is relatively easy
to detect in this type of
breast tissue
66
Different Views
Side-to-Side
MRI - Cancer can have a unique
appearance – many small irregular
white areas that turned out to be
cancer (used for diagnosis)
Top-to-Bottom
67
Calcification Features
• The morphology of individual
calcification, e.g., shape, area,
and brightness
• The heterogeneity of
individual features
characterized by the mean,
the standard deviation, and
the maximum value for each
feature.
• Cluster features such as total
area, compactness
68
Database Approach to
Computer-Aided Diagnosis
Content-based image retrieval techniques can provide
radiologists “visual aids” to increase confidence in
their diagnosis
• The database consists of a large
number of images with verified
pathology results
• Diagnosis is done by submitting the
suspected mass region as a query to
retrieve similar cases from the
database
69
Outline- Part 2
• How is breast cancer:
• Detected
• Diagnosed
• Treated
70
Diagnosis and Treatment
• . Patient feels a breast mass or has an
abnormal radiologic screening exam
• . Surgical biopsy or aspiration
• . Observation (LCIS), lumpectomy or
mastectomy
• . Staging
• . Delivery of adjuvant therapies—radiation
and/or chemotherapy,hormonal therapies
3/12/2016
71
Tumor characteristics
• Invasive vs. Non-invasive .
• Histologic Type-Ductal (85%) vs. Lobular .
• Grade (estimate of the aggressiveness
under microscope) .
• Size .
• Margins .
• Lymph Nodes .
• Estrogen/ Progesterone Receptor (2/3
positive) .
• Her-2/ neu
3/12/2016
72
.
Stage 0 --carcinoma in situ
Stage I – tumor < 2 cm, no
nodes
. Stage II – tumor 2 to 5 cm,
+/-nodes
.
Stages
of
Breast
Cancer
Stage III – locally advanced
disease, fixed or matted lymph
nodes and variable tumor size
.
Stage IV – distant
metastases (bone, liver, lung,
brain)
.
What now?
Stage 0-III
Risk of recurrence is individual
What can we do to reduce the risk of
recurrence in the breast, and
systemically ?
Meet with Radiation Oncologist and
Medical Oncologist
74
How is breast cancer treated?
3. ADJUVANT THERAPY: Medical therapy
to decrease the chance of tumor
recurrence - to improve the chances for
cure
Chemotherapy - many different therapies
Hormonal therapy - tamoxifen, aromatase
inhibitors
4. RADIATION THERAPY - to prevent
tumor recurrence in the remaining breast
tissue; required for breast preserving
therapy
Adjuvant Therapy
Radiation Therapy (local)
Chemotherapy (systemic)
Hormonal agents (systemic)
Each therapy adds to reduction of
recurrent disease.
Therapy
discussion
provider.
is
individualized,
with health care
BREAST CONSERVING THERAPY
(BCT)
Breast cancer
screening programs
Increase mass
awareness
BREAST
CONSERVING
SURGERY
Patients with earlier
stages presenting
to clinic
Better Quality
of life
Better psycho-social
Adjustment
MRM Vs BCT
Randomized trials
Meta-analysis
Comparable local control, Overall survival
Better cosmetic outcome
BCT: EFFECT OF RADIOTHERAPY ON LOCAL
RECURRENCE
5 year gain
16.1%
Node Negative Women
5 year gain
30.1%
Node Positive Women
EBCTCG meta-analysis. Lancet 2005; 366: 2087–2106
Chemotherapy Drugs
.
.
Adriamycin, Epirubicin
.
Taxol, Taxotere
.
.
Navelbine
Cytoxan
.
Methotrexate, 5-fluorouracil
.
Intravenous
Nausea, hair loss, low blood counts, cardiac toxicity,
bladder toxicity, nerve damage
.
Given for adjuvant or recurrent disease.
80
Tamoxifen*
Works by blocking estrogen
receptors in breast cells, inhibiting
their growth
.
Can be given to pre or post menopausal
women
.
Side effects include hot flashes,
depression, increased risk of uterine cancer
and blood clots
.
.
Taken daily by mouth for 5 years
81
Aromatase Inhibitors*
Aromatase is the enzyme that converts
androgens to estrogen
AIs are only given to postmenopausal
women
Examples: Anastrozole/Arimidex,
Letrozole/Femara, Exemestane/Aromasin
.
“May” be more effective than Tamoxifen
Side effects include hot flashes,
depression, osteoporosis, joint pains
.
Taken daily by mouth for variable periods of
82
time
.
Trastuzumab/Herceptin
.
Given to patients whose cancer
cells overexpress Her-2-neu as
measured by IHC or FISH (25 to 30%
of patients)
83
Bisphosphonates
•Bone strengtheners
•Given for therapy-induced osteoporosis or for
cancer that has spread to bone
•Zometa (Zoledronic acid)
•Aredia (Pamidronate)
• Each lowers calcium and has been shown
to reduce the risk of fracture in pts with
cancers metastatic to bone.
Summary
• The breast is a dynamic organ- undergoes cyclical proliferative
changes throughout life under the influence of hormones and
growth factors- so may be likely to be more altered by
environmental carcinogens
• Key function for ER and PR in breast cells. The same hormones
that are important for breast growth during pregnancy are
also important for breast cancer.
•
ER function in signaling through other growth factor receptor
pathways becomes very important in cancer. Production of
estrogen through alternate sources keeps E supply ongoing in
postmenopausal women.