Breast Pathology Flashcards
(105 cards)
1
Q
What is the basic histological unit of the breast?
A
Terminal Duct Lobular Unit (TDLU)
2
Q
What are the two main cell layers in the histology of breast ducts and acini?
A
Inner duct epithelium (E) and outer myoepithelial cells (M)
3
Q
What happens to the breast tissue at menarche?
A
Increase in lobules and stroma
4
Q
What happens to the breast tissue after ovulation?
A
Cell proliferation increases, and intralobular stroma becomes oedematous
5
Q
What changes occur in the breast during pregnancy?
A
Hyperplasia and hypertrophy of lobules with a reduction in stroma
6
Q
Name four inflammatory non-neoplastic diseases of the breast.
A
Acute mastitis, Fat necrosis, Duct ectasia, Granulomatous mastitis
7
Q
What is the main characteristic of non-proliferative benign epithelial lesions like fibrocystic changes?
A
No additional risk of malignancy
8
Q
Proliferative breast disease without atypia includes which conditions?
A
Adenoma, papilloma, typical epithelial hyperplasia
9
Q
Proliferative breast disease with atypia includes which conditions?
A
Atypical ductal hyperplasia, atypical lobular hyperplasia
10
Q
Name a benign epithelial neoplasm of the breast.
A
Papilloma without atypia
11
Q
Name two types of in-situ breast carcinomas.
A
Ductal Carcinoma In Situ (DCIS), Lobular Carcinoma In Situ (LCIS)
12
Q
Name a benign epithelial and stromal neoplasm of the breast.
A
Fibroadenoma
13
Q
Name a malignant epithelial and stromal neoplasm of the breast.
A
Malignant Phyllodes tumour
14
Q
What are the common clinical presentations of breast disease?
A
Pain, palpable mass, nipple discharge, lumpiness
15
Q
What percentage of patients with breast pain have cancer?
A
0.05
16
Q
What percentage of patients with a palpable breast mass have cancer?
A
0.12
17
Q
What percentage of patients with nipple discharge have cancer?
A
0.07
18
Q
What can cause colourless nipple discharge?
A
Fibrocystic disease, Galactocele
19
Q
What can cause blood-stained nipple discharge?
A
Duct papilloma, Duct carcinoma
20
Q
What can cause an inverted nipple?
A
Inflammation, tumours
21
Q
What conditions can present as densities on mammographic screening?
A
Invasive carcinomas, fibroadenomas
22
Q
What conditions can present as calcifications on mammographic screening?
A
In situ carcinomas (DCIS), invasive carcinomas, apocrine cysts, fibroadenoma
23
Q
When does acute mastitis usually occur?
A
During the first month of breastfeeding
24
Q
What are the common organisms causing acute mastitis?
A
Staphylococcus, Streptococcus
25
How does Staphylococcal acute mastitis typically present?
Abscesses
26
How does Streptococcal acute mastitis typically present?
Spreading infection
27
What are the macroscopic features of acute mastitis?
Ranges from an area of acute inflammation to formation of abscesses
28
What are the microscopic features of acute mastitis?
Acute inflammatory infiltrate with neutrophils and necrosis
29
How can fat necrosis present clinically?
Painful palpable mass, skin thickening, or retraction of nipple
30
What can fat necrosis mimic on mammography?
Carcinoma (densities or calcifications)
31
What is a common preceding factor for fat necrosis?
History of trauma or surgery
32
Describe the macroscopic appearance of acute lesions in fat necrosis.
Hemorrhagic, central areas of liquefactive fat necrosis
33
Describe the macroscopic appearance of sub-acute lesions in fat necrosis.
Ill-defined, firm, gray-white nodules with chalky-white foci (calcifications) or dark hemorrhagic areas
34
What are the microscopic features of fat necrosis?
Fat necrosis surrounded by inflammatory cells including neutrophils, macrophages, and giant cells
35
What is the classification of benign epithelial diseases based on?
Subsequent risk of breast cancer
36
What is the risk of breast cancer associated with non-proliferative breast diseases like fibrocystic changes?
Usually not associated with an increased risk (risk same as for normal population)
37
What age group is most commonly affected by fibrocystic changes?
40-55 years; peak in the perimenopausal age
38
What is the suspected aetiopathogenesis of fibrocystic changes?
Hormonal imbalances throughout reproductive life affecting epithelium and stroma
39
How do fibrocystic changes typically present clinically?
Majority asymptomatic; in 10% ill-defined lumpiness/ 'lumpy bumpy breast'
40
What are the mammographic findings in fibrocystic changes?
A dense breast with cysts
41
What are the three main morphological features of fibrocystic changes?
Adenosis, Cyst formation, Fibrosis
42
Describe the macroscopic appearance of cysts in fibrocystic changes.
Thin-walled, multiple, <1cm containing clear fluid (Blue domed cysts)
43
What is adenosis microscopically in fibrocystic changes?
Increased number of acini per lobule, lined by cuboidal or columnar (metaplastic) epithelium; hyperplasia of lobular acini
44
Describe cyst formation microscopically in fibrocystic changes.
Cystic dilatation of terminal ducts & acini; cysts lined by flattened epithelium or metaplastic apocrine epithelium
45
What is metaplastic apocrine epithelium?
Tall columnar cells with eosinophilic cytoplasm
46
What characterizes proliferative breast disease?
Proliferation of ductal epithelial cells +/- atypia
47
Name four types of proliferative breast disease.
Epithelial hyperplasia, Papillomas, Radial scar, Sclerosing adenosis
48
How are proliferative breast diseases often detected?
Screening mammography (densities or calcifications) or as incidental findings in biopsies
49
What is the risk of malignancy for epithelial hyperplasia without atypia (usual/typical epithelial hyperplasia)?
2 times the normal risk
50
What is the risk of malignancy for epithelial hyperplasia with atypia (atypical ductal/lobular epithelial hyperplasia)?
4 times the normal risk
51
Where do large duct papillomas usually occur?
Solitary, in the lactiferous sinuses of the nipple
52
Where do small duct papillomas usually occur?
Multiple, deep in the ducts
53
What are the microscopic features of papillomas?
Papillary structures with branching fibrovascular cores, lined by epithelial and myoepithelial cells; may show epithelial hyperplasia and apocrine metaplasia
54
What is a common clinical presentation of large duct papillomas?
Nipple discharge (in >80% of cases)
55
Why might nipple discharge be blood-stained in papillomas?
Due to torsion of the fibrovascular stalk causing infarction
56
What is gynaecomastia?
Unilateral/bilateral enlargement of the male breast
57
What is the pathogenesis of gynaecomastia?
Due to an imbalance between oestrogens and androgens
58
Name three predisposing causes for gynaecomastia.
Puberty, old age, cirrhosis (also testicular neoplasms, drugs, Klinefelter's Syndrome)
59
What are the macroscopic features of gynaecomastia?
Button-like subareolar enlargement
60
What are the microscopic features of gynaecomastia?
Epithelial hyperplasia of the duct epithelium, increase in collagenous stroma, no lobules
61
Where do most breast carcinomas originate?
Terminal duct lobular unit (TDLU)
62
What is the most common cancer in women worldwide and in Sri Lanka?
Breast carcinoma (27% of all cancers in SL in 2021)
63
What is the commonest site for breast carcinoma?
Upper outer quadrant
64
What percentage of breast cancers are familial?
0.12
65
Mutations in which genes are associated with familial breast carcinoma?
BRCA1, BRCA2, P53
66
What is the risk of breast cancer by age 70 for BRCA1 mutation carriers?
40-90%
67
What is the risk of breast cancer by age 70 for BRCA2 mutation carriers?
30-90%
68
What is the risk of breast cancer for P53 mutation carriers?
>90%
69
What is the key difference between in-situ and invasive carcinoma?
In-situ: basement membrane intact; Invasive: basement membrane infiltrated by carcinoma
70
What are the two main types of carcinoma in-situ?
Duct Carcinoma In Situ (DCIS) and Lobular Carcinoma In Situ (LCIS)
71
How is DCIS often detected in asymptomatic patients?
Mammography (calcifications)
72
Name the two main histological subtypes of DCIS.
Non-comedo type and Comedo type
73
Which type of DCIS is associated with central necrosis and can result in nipple discharge?
Comedo type DCIS
74
What is the prognosis of DCIS if treated with mastectomy?
Curative in 95%
75
Is calcification typically seen in LCIS?
No, therefore not usually detected on mammography
76
What is Paget disease of the breast?
A rare manifestation of breast cancer (1-4%) presenting as ulceration of the nipple
77
If a patient has Paget disease of the breast with no palpable lump, what is the likely underlying pathology?
Duct carcinoma in-situ (DCIS)
78
If a patient has Paget disease of the breast with a palpable lump, what is the likely underlying pathology?
Invasive Duct Carcinoma
79
What is the most common histological type of invasive breast carcinoma?
Invasive carcinoma, No Special Type (NST) (also known as invasive duct carcinoma NST), comprising 60-80% of cases.
80
Describe the macroscopic appearance of Invasive Carcinoma (NST).
Poorly defined, irregular, firm/hard, cut surface like an 'unripe pear' due to calcification and fibrosis.
81
What is a characteristic microscopic growth pattern of Invasive Lobular Carcinoma?
Discohesive, diffusely infiltrative cells arranged around normal ducts in a 'targetoid' or 'Indian file' manner; no duct or tubule formation.
82
What tumour suppressor adhesion protein is often lost in Invasive Lobular Carcinoma?
E-Cadherin
83
Name two common sites of distant metastasis for usual breast carcinomas.
Lung, Bone, Liver
84
Name two unusual sites of spread for lobular carcinoma.
Peritoneum/retroperitoneum, Leptomeninges (carcinomatous meningitis), GIT, Ovaries, Uterus
85
How does the prognosis of in-situ carcinoma compare to invasive carcinoma?
In-situ carcinomas have a better prognosis.
86
How does tumour size affect 10-year survival in breast cancer (e.g., <1cm vs >2cm)?
<1cm: >90% survival; >2cm: 77% survival
87
How does the number of involved lymph nodes affect 10-year survival (e.g., None, 1-3, >10)?
None: 80%; 1-3: 40%; >10: 10%
88
What is the prognosis for inflammatory carcinoma?
Bad prognosis; 3-year survival 3-10%
89
Which histological types of breast cancer generally have a better prognosis than duct carcinoma NST?
Tubular, mucinous, lobular, papillary, adenoid cystic
90
How does ER/PR positivity affect prognosis?
Better prognosis
91
How does HER2/neu positivity generally affect clinical outcome without targeted therapy?
Poor clinical outcome
92
What is the Nottingham Prognostic Index (NPI) formula?
NPI = [0.2 x S] + N + G (S=size in cm, N=nodal status score, G=grade score)
93
What is the commonest benign tumour of the breast?
Fibroadenoma
94
What is the origin of a fibroadenoma?
Intralobular stroma
95
What are the two components of a fibroadenoma?
Epithelial and stromal (fibrous) components
96
What is the typical clinical presentation of a fibroadenoma?
Palpable, mobile mass, commonly in 20-30 year olds, upper outer quadrant.
97
Describe the macroscopic appearance of a fibroadenoma.
Well-defined, encapsulated mass, grayish white, slit-like spaces.
98
What is the typical clinical behavior of a fibroadenoma?
Benign, very low risk of malignancy.
99
What is the peak age for Phyllodes tumour?
60 years
100
What are the microscopic features distinguishing benign vs malignant Phyllodes tumour?
Stromal changes: overgrowth with hypercellularity, mitosis (more in malignant)
101
What is the recommended treatment for malignant Phyllodes tumour?
Wide local excision
102
Name one advantage of Fine Needle Aspiration (FNA) cytology for palpable breast lumps.
Simple outpatient procedure, less expensive, less painful, no scar
103
Name one disadvantage of Fine Needle Aspiration (FNA) cytology.
Less accurate than histology
104
Name one advantage of Trucut biopsy over FNA.
Histological diagnosis (more accurate), can perform receptor status preoperatively
105
What is a frozen section biopsy primarily used for?
Intraoperative diagnosis for suspicious lesions
